diff options
25 files changed, 6099 insertions, 0 deletions
diff --git a/target/linux/generic/patches-3.18/080-00-fib_trie-Fix-proc-net-fib_trie-when-CONFIG_IP_MULTIP.patch b/target/linux/generic/patches-3.18/080-00-fib_trie-Fix-proc-net-fib_trie-when-CONFIG_IP_MULTIP.patch new file mode 100644 index 0000000000..5d99367ad4 --- /dev/null +++ b/target/linux/generic/patches-3.18/080-00-fib_trie-Fix-proc-net-fib_trie-when-CONFIG_IP_MULTIP.patch @@ -0,0 +1,46 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Tue, 2 Dec 2014 10:58:21 -0800 +Subject: [PATCH] fib_trie: Fix /proc/net/fib_trie when + CONFIG_IP_MULTIPLE_TABLES is not defined + +In recent testing I had disabled CONFIG_IP_MULTIPLE_TABLES and as a result +when I ran "cat /proc/net/fib_trie" the main trie was displayed multiple +times. I found that the problem line of code was in the function +fib_trie_seq_next. Specifically the line below caused the indexes to go in +the opposite direction of our traversal: + + h = tb->tb_id & (FIB_TABLE_HASHSZ - 1); + +This issue was that the RT tables are defined such that RT_TABLE_LOCAL is ID +255, while it is located at TABLE_LOCAL_INDEX of 0, and RT_TABLE_MAIN is 254 +with a TABLE_MAIN_INDEX of 1. This means that the above line will return 1 +for the local table and 0 for main. The result is that fib_trie_seq_next +will return NULL at the end of the local table, fib_trie_seq_start will +return the start of the main table, and then fib_trie_seq_next will loop on +main forever as h will always return 0. + +The fix for this is to reverse the ordering of the two tables. It has the +advantage of making it so that the tables now print in the same order +regardless of if multiple tables are enabled or not. In order to make the +definition consistent with the multiple tables case I simply masked the to +RT_TABLE_XXX values by (FIB_TABLE_HASHSZ - 1). This way the two table +layouts should always stay consistent. + +Fixes: 93456b6 ("[IPV4]: Unify access to the routing tables") +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/include/net/ip_fib.h ++++ b/include/net/ip_fib.h +@@ -201,8 +201,8 @@ void fib_free_table(struct fib_table *tb + + #ifndef CONFIG_IP_MULTIPLE_TABLES + +-#define TABLE_LOCAL_INDEX 0 +-#define TABLE_MAIN_INDEX 1 ++#define TABLE_LOCAL_INDEX (RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1)) ++#define TABLE_MAIN_INDEX (RT_TABLE_MAIN & (FIB_TABLE_HASHSZ - 1)) + + static inline struct fib_table *fib_get_table(struct net *net, u32 id) + { diff --git a/target/linux/generic/patches-3.18/080-01-fib_trie-Fix-trie-balancing-issue-if-new-node-pushes.patch b/target/linux/generic/patches-3.18/080-01-fib_trie-Fix-trie-balancing-issue-if-new-node-pushes.patch new file mode 100644 index 0000000000..4e09f8a189 --- /dev/null +++ b/target/linux/generic/patches-3.18/080-01-fib_trie-Fix-trie-balancing-issue-if-new-node-pushes.patch @@ -0,0 +1,72 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Wed, 10 Dec 2014 21:49:22 -0800 +Subject: [PATCH] fib_trie: Fix trie balancing issue if new node pushes down + existing node + +This patch addresses an issue with the level compression of the fib_trie. +Specifically in the case of adding a new leaf that triggers a new node to +be added that takes the place of the old node. The result is a trie where +the 1 child tnode is on one side and one leaf is on the other which gives +you a very deep trie. Below is the script I used to generate a trie on +dummy0 with a 10.X.X.X family of addresses. + + ip link add type dummy + ipval=184549374 + bit=2 + for i in `seq 1 23` + do + ifconfig dummy0:$bit $ipval/8 + ipval=`expr $ipval - $bit` + bit=`expr $bit \* 2` + done + cat /proc/net/fib_triestat + +Running the script before the patch: + + Local: + Aver depth: 10.82 + Max depth: 23 + Leaves: 29 + Prefixes: 30 + Internal nodes: 27 + 1: 26 2: 1 + Pointers: 56 + Null ptrs: 1 + Total size: 5 kB + +After applying the patch and repeating: + + Local: + Aver depth: 4.72 + Max depth: 9 + Leaves: 29 + Prefixes: 30 + Internal nodes: 12 + 1: 3 2: 2 3: 7 + Pointers: 70 + Null ptrs: 30 + Total size: 4 kB + +What this fix does is start the rebalance at the newly created tnode +instead of at the parent tnode. This way if there is a gap between the +parent and the new node it doesn't prevent the new tnode from being +coalesced with any pre-existing nodes that may have been pushed into one +of the new nodes child branches. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -1143,8 +1143,9 @@ static struct list_head *fib_insert_node + put_child(tp, cindex, (struct rt_trie_node *)tn); + } else { + rcu_assign_pointer(t->trie, (struct rt_trie_node *)tn); +- tp = tn; + } ++ ++ tp = tn; + } + + if (tp && tp->pos + tp->bits > 32) diff --git a/target/linux/generic/patches-3.18/080-02-fib_trie-Update-usage-stats-to-be-percpu-instead-of-.patch b/target/linux/generic/patches-3.18/080-02-fib_trie-Update-usage-stats-to-be-percpu-instead-of-.patch new file mode 100644 index 0000000000..8384009658 --- /dev/null +++ b/target/linux/generic/patches-3.18/080-02-fib_trie-Update-usage-stats-to-be-percpu-instead-of-.patch @@ -0,0 +1,200 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Wed, 31 Dec 2014 10:55:29 -0800 +Subject: [PATCH] fib_trie: Update usage stats to be percpu instead of + global variables + +The trie usage stats were currently being shared by all threads that were +calling fib_table_lookup. As a result when multiple threads were +performing lookups simultaneously the trie would begin to cache bounce +between those threads. + +In order to prevent this I have updated the usage stats to use a set of +percpu variables. By doing this we should be able to avoid the cache +bouncing and still make use of these stats. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_frontend.c ++++ b/net/ipv4/fib_frontend.c +@@ -67,7 +67,7 @@ static int __net_init fib4_rules_init(st + return 0; + + fail: +- kfree(local_table); ++ fib_free_table(local_table); + return -ENOMEM; + } + #else +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -153,7 +153,7 @@ struct trie_stat { + struct trie { + struct rt_trie_node __rcu *trie; + #ifdef CONFIG_IP_FIB_TRIE_STATS +- struct trie_use_stats stats; ++ struct trie_use_stats __percpu *stats; + #endif + }; + +@@ -631,7 +631,7 @@ static struct rt_trie_node *resize(struc + if (IS_ERR(tn)) { + tn = old_tn; + #ifdef CONFIG_IP_FIB_TRIE_STATS +- t->stats.resize_node_skipped++; ++ this_cpu_inc(t->stats->resize_node_skipped); + #endif + break; + } +@@ -658,7 +658,7 @@ static struct rt_trie_node *resize(struc + if (IS_ERR(tn)) { + tn = old_tn; + #ifdef CONFIG_IP_FIB_TRIE_STATS +- t->stats.resize_node_skipped++; ++ this_cpu_inc(t->stats->resize_node_skipped); + #endif + break; + } +@@ -1357,7 +1357,7 @@ static int check_leaf(struct fib_table * + err = fib_props[fa->fa_type].error; + if (err) { + #ifdef CONFIG_IP_FIB_TRIE_STATS +- t->stats.semantic_match_passed++; ++ this_cpu_inc(t->stats->semantic_match_passed); + #endif + return err; + } +@@ -1372,7 +1372,7 @@ static int check_leaf(struct fib_table * + continue; + + #ifdef CONFIG_IP_FIB_TRIE_STATS +- t->stats.semantic_match_passed++; ++ this_cpu_inc(t->stats->semantic_match_passed); + #endif + res->prefixlen = li->plen; + res->nh_sel = nhsel; +@@ -1388,7 +1388,7 @@ static int check_leaf(struct fib_table * + } + + #ifdef CONFIG_IP_FIB_TRIE_STATS +- t->stats.semantic_match_miss++; ++ this_cpu_inc(t->stats->semantic_match_miss); + #endif + } + +@@ -1399,6 +1399,9 @@ int fib_table_lookup(struct fib_table *t + struct fib_result *res, int fib_flags) + { + struct trie *t = (struct trie *) tb->tb_data; ++#ifdef CONFIG_IP_FIB_TRIE_STATS ++ struct trie_use_stats __percpu *stats = t->stats; ++#endif + int ret; + struct rt_trie_node *n; + struct tnode *pn; +@@ -1417,7 +1420,7 @@ int fib_table_lookup(struct fib_table *t + goto failed; + + #ifdef CONFIG_IP_FIB_TRIE_STATS +- t->stats.gets++; ++ this_cpu_inc(stats->gets); + #endif + + /* Just a leaf? */ +@@ -1441,7 +1444,7 @@ int fib_table_lookup(struct fib_table *t + + if (n == NULL) { + #ifdef CONFIG_IP_FIB_TRIE_STATS +- t->stats.null_node_hit++; ++ this_cpu_inc(stats->null_node_hit); + #endif + goto backtrace; + } +@@ -1576,7 +1579,7 @@ backtrace: + chopped_off = 0; + + #ifdef CONFIG_IP_FIB_TRIE_STATS +- t->stats.backtrack++; ++ this_cpu_inc(stats->backtrack); + #endif + goto backtrace; + } +@@ -1830,6 +1833,11 @@ int fib_table_flush(struct fib_table *tb + + void fib_free_table(struct fib_table *tb) + { ++#ifdef CONFIG_IP_FIB_TRIE_STATS ++ struct trie *t = (struct trie *)tb->tb_data; ++ ++ free_percpu(t->stats); ++#endif /* CONFIG_IP_FIB_TRIE_STATS */ + kfree(tb); + } + +@@ -1973,7 +1981,14 @@ struct fib_table *fib_trie_table(u32 id) + tb->tb_num_default = 0; + + t = (struct trie *) tb->tb_data; +- memset(t, 0, sizeof(*t)); ++ RCU_INIT_POINTER(t->trie, NULL); ++#ifdef CONFIG_IP_FIB_TRIE_STATS ++ t->stats = alloc_percpu(struct trie_use_stats); ++ if (!t->stats) { ++ kfree(tb); ++ tb = NULL; ++ } ++#endif + + return tb; + } +@@ -2139,18 +2154,31 @@ static void trie_show_stats(struct seq_f + + #ifdef CONFIG_IP_FIB_TRIE_STATS + static void trie_show_usage(struct seq_file *seq, +- const struct trie_use_stats *stats) ++ const struct trie_use_stats __percpu *stats) + { ++ struct trie_use_stats s = { 0 }; ++ int cpu; ++ ++ /* loop through all of the CPUs and gather up the stats */ ++ for_each_possible_cpu(cpu) { ++ const struct trie_use_stats *pcpu = per_cpu_ptr(stats, cpu); ++ ++ s.gets += pcpu->gets; ++ s.backtrack += pcpu->backtrack; ++ s.semantic_match_passed += pcpu->semantic_match_passed; ++ s.semantic_match_miss += pcpu->semantic_match_miss; ++ s.null_node_hit += pcpu->null_node_hit; ++ s.resize_node_skipped += pcpu->resize_node_skipped; ++ } ++ + seq_printf(seq, "\nCounters:\n---------\n"); +- seq_printf(seq, "gets = %u\n", stats->gets); +- seq_printf(seq, "backtracks = %u\n", stats->backtrack); ++ seq_printf(seq, "gets = %u\n", s.gets); ++ seq_printf(seq, "backtracks = %u\n", s.backtrack); + seq_printf(seq, "semantic match passed = %u\n", +- stats->semantic_match_passed); +- seq_printf(seq, "semantic match miss = %u\n", +- stats->semantic_match_miss); +- seq_printf(seq, "null node hit= %u\n", stats->null_node_hit); +- seq_printf(seq, "skipped node resize = %u\n\n", +- stats->resize_node_skipped); ++ s.semantic_match_passed); ++ seq_printf(seq, "semantic match miss = %u\n", s.semantic_match_miss); ++ seq_printf(seq, "null node hit= %u\n", s.null_node_hit); ++ seq_printf(seq, "skipped node resize = %u\n\n", s.resize_node_skipped); + } + #endif /* CONFIG_IP_FIB_TRIE_STATS */ + +@@ -2191,7 +2219,7 @@ static int fib_triestat_seq_show(struct + trie_collect_stats(t, &stat); + trie_show_stats(seq, &stat); + #ifdef CONFIG_IP_FIB_TRIE_STATS +- trie_show_usage(seq, &t->stats); ++ trie_show_usage(seq, t->stats); + #endif + } + } diff --git a/target/linux/generic/patches-3.18/080-03-fib_trie-Make-leaf-and-tnode-more-uniform.patch b/target/linux/generic/patches-3.18/080-03-fib_trie-Make-leaf-and-tnode-more-uniform.patch new file mode 100644 index 0000000000..2eb3e4c4b8 --- /dev/null +++ b/target/linux/generic/patches-3.18/080-03-fib_trie-Make-leaf-and-tnode-more-uniform.patch @@ -0,0 +1,421 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Wed, 31 Dec 2014 10:55:35 -0800 +Subject: [PATCH] fib_trie: Make leaf and tnode more uniform + +This change makes some fundamental changes to the way leaves and tnodes are +constructed. The big differences are: +1. Leaves now populate pos and bits indicating their full key size. +2. Trie nodes now mask out their lower bits to be consistent with the leaf +3. Both structures have been reordered so that rt_trie_node now consisists + of a much larger region including the pos, bits, and rcu portions of + the tnode structure. + +On 32b systems this will result in the leaf being 4B larger as the pos and +bits values were added to a hole created by the key as it was only 4B in +length. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -87,24 +87,38 @@ + + typedef unsigned int t_key; + +-#define T_TNODE 0 +-#define T_LEAF 1 +-#define NODE_TYPE_MASK 0x1UL +-#define NODE_TYPE(node) ((node)->parent & NODE_TYPE_MASK) ++#define IS_TNODE(n) ((n)->bits) ++#define IS_LEAF(n) (!(n)->bits) + +-#define IS_TNODE(n) (!(n->parent & T_LEAF)) +-#define IS_LEAF(n) (n->parent & T_LEAF) ++struct tnode { ++ t_key key; ++ unsigned char bits; /* 2log(KEYLENGTH) bits needed */ ++ unsigned char pos; /* 2log(KEYLENGTH) bits needed */ ++ struct tnode __rcu *parent; ++ union { ++ struct rcu_head rcu; ++ struct tnode *tnode_free; ++ }; ++ unsigned int full_children; /* KEYLENGTH bits needed */ ++ unsigned int empty_children; /* KEYLENGTH bits needed */ ++ struct rt_trie_node __rcu *child[0]; ++}; + + struct rt_trie_node { +- unsigned long parent; + t_key key; ++ unsigned char bits; ++ unsigned char pos; ++ struct tnode __rcu *parent; ++ struct rcu_head rcu; + }; + + struct leaf { +- unsigned long parent; + t_key key; +- struct hlist_head list; ++ unsigned char bits; ++ unsigned char pos; ++ struct tnode __rcu *parent; + struct rcu_head rcu; ++ struct hlist_head list; + }; + + struct leaf_info { +@@ -115,20 +129,6 @@ struct leaf_info { + struct rcu_head rcu; + }; + +-struct tnode { +- unsigned long parent; +- t_key key; +- unsigned char pos; /* 2log(KEYLENGTH) bits needed */ +- unsigned char bits; /* 2log(KEYLENGTH) bits needed */ +- unsigned int full_children; /* KEYLENGTH bits needed */ +- unsigned int empty_children; /* KEYLENGTH bits needed */ +- union { +- struct rcu_head rcu; +- struct tnode *tnode_free; +- }; +- struct rt_trie_node __rcu *child[0]; +-}; +- + #ifdef CONFIG_IP_FIB_TRIE_STATS + struct trie_use_stats { + unsigned int gets; +@@ -176,38 +176,27 @@ static const int sync_pages = 128; + static struct kmem_cache *fn_alias_kmem __read_mostly; + static struct kmem_cache *trie_leaf_kmem __read_mostly; + +-/* +- * caller must hold RTNL +- */ +-static inline struct tnode *node_parent(const struct rt_trie_node *node) +-{ +- unsigned long parent; ++/* caller must hold RTNL */ ++#define node_parent(n) rtnl_dereference((n)->parent) + +- parent = rcu_dereference_index_check(node->parent, lockdep_rtnl_is_held()); ++/* caller must hold RCU read lock or RTNL */ ++#define node_parent_rcu(n) rcu_dereference_rtnl((n)->parent) + +- return (struct tnode *)(parent & ~NODE_TYPE_MASK); +-} +- +-/* +- * caller must hold RCU read lock or RTNL +- */ +-static inline struct tnode *node_parent_rcu(const struct rt_trie_node *node) ++/* wrapper for rcu_assign_pointer */ ++static inline void node_set_parent(struct rt_trie_node *node, struct tnode *ptr) + { +- unsigned long parent; +- +- parent = rcu_dereference_index_check(node->parent, rcu_read_lock_held() || +- lockdep_rtnl_is_held()); +- +- return (struct tnode *)(parent & ~NODE_TYPE_MASK); ++ if (node) ++ rcu_assign_pointer(node->parent, ptr); + } + +-/* Same as rcu_assign_pointer +- * but that macro() assumes that value is a pointer. ++#define NODE_INIT_PARENT(n, p) RCU_INIT_POINTER((n)->parent, p) ++ ++/* This provides us with the number of children in this node, in the case of a ++ * leaf this will return 0 meaning none of the children are accessible. + */ +-static inline void node_set_parent(struct rt_trie_node *node, struct tnode *ptr) ++static inline int tnode_child_length(const struct tnode *tn) + { +- smp_wmb(); +- node->parent = (unsigned long)ptr | NODE_TYPE(node); ++ return (1ul << tn->bits) & ~(1ul); + } + + /* +@@ -215,7 +204,7 @@ static inline void node_set_parent(struc + */ + static inline struct rt_trie_node *tnode_get_child(const struct tnode *tn, unsigned int i) + { +- BUG_ON(i >= 1U << tn->bits); ++ BUG_ON(i >= tnode_child_length(tn)); + + return rtnl_dereference(tn->child[i]); + } +@@ -225,16 +214,11 @@ static inline struct rt_trie_node *tnode + */ + static inline struct rt_trie_node *tnode_get_child_rcu(const struct tnode *tn, unsigned int i) + { +- BUG_ON(i >= 1U << tn->bits); ++ BUG_ON(i >= tnode_child_length(tn)); + + return rcu_dereference_rtnl(tn->child[i]); + } + +-static inline int tnode_child_length(const struct tnode *tn) +-{ +- return 1 << tn->bits; +-} +- + static inline t_key mask_pfx(t_key k, unsigned int l) + { + return (l == 0) ? 0 : k >> (KEYLENGTH-l) << (KEYLENGTH-l); +@@ -336,11 +320,6 @@ static inline int tkey_mismatch(t_key a, + + */ + +-static inline void check_tnode(const struct tnode *tn) +-{ +- WARN_ON(tn && tn->pos+tn->bits > 32); +-} +- + static const int halve_threshold = 25; + static const int inflate_threshold = 50; + static const int halve_threshold_root = 15; +@@ -426,11 +405,20 @@ static void tnode_free_flush(void) + } + } + +-static struct leaf *leaf_new(void) ++static struct leaf *leaf_new(t_key key) + { + struct leaf *l = kmem_cache_alloc(trie_leaf_kmem, GFP_KERNEL); + if (l) { +- l->parent = T_LEAF; ++ l->parent = NULL; ++ /* set key and pos to reflect full key value ++ * any trailing zeros in the key should be ignored ++ * as the nodes are searched ++ */ ++ l->key = key; ++ l->pos = KEYLENGTH; ++ /* set bits to 0 indicating we are not a tnode */ ++ l->bits = 0; ++ + INIT_HLIST_HEAD(&l->list); + } + return l; +@@ -451,12 +439,16 @@ static struct tnode *tnode_new(t_key key + { + size_t sz = sizeof(struct tnode) + (sizeof(struct rt_trie_node *) << bits); + struct tnode *tn = tnode_alloc(sz); ++ unsigned int shift = pos + bits; ++ ++ /* verify bits and pos their msb bits clear and values are valid */ ++ BUG_ON(!bits || (shift > KEYLENGTH)); + + if (tn) { +- tn->parent = T_TNODE; ++ tn->parent = NULL; + tn->pos = pos; + tn->bits = bits; +- tn->key = key; ++ tn->key = mask_pfx(key, pos); + tn->full_children = 0; + tn->empty_children = 1<<bits; + } +@@ -473,10 +465,7 @@ static struct tnode *tnode_new(t_key key + + static inline int tnode_full(const struct tnode *tn, const struct rt_trie_node *n) + { +- if (n == NULL || IS_LEAF(n)) +- return 0; +- +- return ((struct tnode *) n)->pos == tn->pos + tn->bits; ++ return n && IS_TNODE(n) && (n->pos == (tn->pos + tn->bits)); + } + + static inline void put_child(struct tnode *tn, int i, +@@ -514,8 +503,7 @@ static void tnode_put_child_reorg(struct + else if (!wasfull && isfull) + tn->full_children++; + +- if (n) +- node_set_parent(n, tn); ++ node_set_parent(n, tn); + + rcu_assign_pointer(tn->child[i], n); + } +@@ -523,7 +511,7 @@ static void tnode_put_child_reorg(struct + #define MAX_WORK 10 + static struct rt_trie_node *resize(struct trie *t, struct tnode *tn) + { +- int i; ++ struct rt_trie_node *n = NULL; + struct tnode *old_tn; + int inflate_threshold_use; + int halve_threshold_use; +@@ -536,12 +524,11 @@ static struct rt_trie_node *resize(struc + tn, inflate_threshold, halve_threshold); + + /* No children */ +- if (tn->empty_children == tnode_child_length(tn)) { +- tnode_free_safe(tn); +- return NULL; +- } ++ if (tn->empty_children > (tnode_child_length(tn) - 1)) ++ goto no_children; ++ + /* One child */ +- if (tn->empty_children == tnode_child_length(tn) - 1) ++ if (tn->empty_children == (tnode_child_length(tn) - 1)) + goto one_child; + /* + * Double as long as the resulting node has a number of +@@ -607,11 +594,9 @@ static struct rt_trie_node *resize(struc + * + */ + +- check_tnode(tn); +- + /* Keep root node larger */ + +- if (!node_parent((struct rt_trie_node *)tn)) { ++ if (!node_parent(tn)) { + inflate_threshold_use = inflate_threshold_root; + halve_threshold_use = halve_threshold_root; + } else { +@@ -637,8 +622,6 @@ static struct rt_trie_node *resize(struc + } + } + +- check_tnode(tn); +- + /* Return if at least one inflate is run */ + if (max_work != MAX_WORK) + return (struct rt_trie_node *) tn; +@@ -666,21 +649,16 @@ static struct rt_trie_node *resize(struc + + + /* Only one child remains */ +- if (tn->empty_children == tnode_child_length(tn) - 1) { ++ if (tn->empty_children == (tnode_child_length(tn) - 1)) { ++ unsigned long i; + one_child: +- for (i = 0; i < tnode_child_length(tn); i++) { +- struct rt_trie_node *n; +- +- n = rtnl_dereference(tn->child[i]); +- if (!n) +- continue; +- +- /* compress one level */ +- +- node_set_parent(n, NULL); +- tnode_free_safe(tn); +- return n; +- } ++ for (i = tnode_child_length(tn); !n && i;) ++ n = tnode_get_child(tn, --i); ++no_children: ++ /* compress one level */ ++ node_set_parent(n, NULL); ++ tnode_free_safe(tn); ++ return n; + } + return (struct rt_trie_node *) tn; + } +@@ -760,8 +738,7 @@ static struct tnode *inflate(struct trie + + /* A leaf or an internal node with skipped bits */ + +- if (IS_LEAF(node) || ((struct tnode *) node)->pos > +- tn->pos + tn->bits - 1) { ++ if (IS_LEAF(node) || (node->pos > (tn->pos + tn->bits - 1))) { + put_child(tn, + tkey_extract_bits(node->key, oldtnode->pos, oldtnode->bits + 1), + node); +@@ -958,11 +935,9 @@ fib_find_node(struct trie *t, u32 key) + pos = 0; + n = rcu_dereference_rtnl(t->trie); + +- while (n != NULL && NODE_TYPE(n) == T_TNODE) { ++ while (n && IS_TNODE(n)) { + tn = (struct tnode *) n; + +- check_tnode(tn); +- + if (tkey_sub_equals(tn->key, pos, tn->pos-pos, key)) { + pos = tn->pos + tn->bits; + n = tnode_get_child_rcu(tn, +@@ -988,7 +963,7 @@ static void trie_rebalance(struct trie * + + key = tn->key; + +- while (tn != NULL && (tp = node_parent((struct rt_trie_node *)tn)) != NULL) { ++ while (tn != NULL && (tp = node_parent(tn)) != NULL) { + cindex = tkey_extract_bits(key, tp->pos, tp->bits); + wasfull = tnode_full(tp, tnode_get_child(tp, cindex)); + tn = (struct tnode *)resize(t, tn); +@@ -996,7 +971,7 @@ static void trie_rebalance(struct trie * + tnode_put_child_reorg(tp, cindex, + (struct rt_trie_node *)tn, wasfull); + +- tp = node_parent((struct rt_trie_node *) tn); ++ tp = node_parent(tn); + if (!tp) + rcu_assign_pointer(t->trie, (struct rt_trie_node *)tn); + +@@ -1048,11 +1023,9 @@ static struct list_head *fib_insert_node + * If it doesn't, we need to replace it with a T_TNODE. + */ + +- while (n != NULL && NODE_TYPE(n) == T_TNODE) { ++ while (n && IS_TNODE(n)) { + tn = (struct tnode *) n; + +- check_tnode(tn); +- + if (tkey_sub_equals(tn->key, pos, tn->pos-pos, key)) { + tp = tn; + pos = tn->pos + tn->bits; +@@ -1087,12 +1060,11 @@ static struct list_head *fib_insert_node + insert_leaf_info(&l->list, li); + goto done; + } +- l = leaf_new(); ++ l = leaf_new(key); + + if (!l) + return NULL; + +- l->key = key; + li = leaf_info_new(plen); + + if (!li) { +@@ -1569,7 +1541,7 @@ backtrace: + if (chopped_off <= pn->bits) { + cindex &= ~(1 << (chopped_off-1)); + } else { +- struct tnode *parent = node_parent_rcu((struct rt_trie_node *) pn); ++ struct tnode *parent = node_parent_rcu(pn); + if (!parent) + goto failed; + +@@ -1597,7 +1569,7 @@ EXPORT_SYMBOL_GPL(fib_table_lookup); + */ + static void trie_leaf_remove(struct trie *t, struct leaf *l) + { +- struct tnode *tp = node_parent((struct rt_trie_node *) l); ++ struct tnode *tp = node_parent(l); + + pr_debug("entering trie_leaf_remove(%p)\n", l); + +@@ -2375,7 +2347,7 @@ static int fib_trie_seq_show(struct seq_ + + if (IS_TNODE(n)) { + struct tnode *tn = (struct tnode *) n; +- __be32 prf = htonl(mask_pfx(tn->key, tn->pos)); ++ __be32 prf = htonl(tn->key); + + seq_indent(seq, iter->depth-1); + seq_printf(seq, " +-- %pI4/%d %d %d %d\n", diff --git a/target/linux/generic/patches-3.18/080-04-fib_trie-Merge-tnode_free-and-leaf_free-into-node_fr.patch b/target/linux/generic/patches-3.18/080-04-fib_trie-Merge-tnode_free-and-leaf_free-into-node_fr.patch new file mode 100644 index 0000000000..cdc2e3b39e --- /dev/null +++ b/target/linux/generic/patches-3.18/080-04-fib_trie-Merge-tnode_free-and-leaf_free-into-node_fr.patch @@ -0,0 +1,209 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Wed, 31 Dec 2014 10:55:41 -0800 +Subject: [PATCH] fib_trie: Merge tnode_free and leaf_free into node_free + +Both the leaf and the tnode had an rcu_head in them, but they had them in +slightly different places. Since we now have them in the same spot and +know that any node with bits == 0 is a leaf and the rest are either vmalloc +or kmalloc tnodes depending on the value of bits it makes it easy to combine +the functions and reduce overhead. + +In addition I have taken advantage of the rcu_head pointer to go ahead and +put together a simple linked list instead of using the tnode pointer as +this way we can merge either type of structure for freeing. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -95,15 +95,17 @@ struct tnode { + unsigned char bits; /* 2log(KEYLENGTH) bits needed */ + unsigned char pos; /* 2log(KEYLENGTH) bits needed */ + struct tnode __rcu *parent; +- union { +- struct rcu_head rcu; +- struct tnode *tnode_free; +- }; ++ struct rcu_head rcu; ++ /* everything above this comment must be the same as rt_trie_node */ + unsigned int full_children; /* KEYLENGTH bits needed */ + unsigned int empty_children; /* KEYLENGTH bits needed */ + struct rt_trie_node __rcu *child[0]; + }; + ++/* This struct represents the shared bits between tnode and leaf. If any ++ * ordering is changed here is must also be updated in tnode and leaf as ++ * well. ++ */ + struct rt_trie_node { + t_key key; + unsigned char bits; +@@ -118,6 +120,7 @@ struct leaf { + unsigned char pos; + struct tnode __rcu *parent; + struct rcu_head rcu; ++ /* everything above this comment must be the same as rt_trie_node */ + struct hlist_head list; + }; + +@@ -163,7 +166,7 @@ static struct rt_trie_node *resize(struc + static struct tnode *inflate(struct trie *t, struct tnode *tn); + static struct tnode *halve(struct trie *t, struct tnode *tn); + /* tnodes to free after resize(); protected by RTNL */ +-static struct tnode *tnode_free_head; ++static struct callback_head *tnode_free_head; + static size_t tnode_free_size; + + /* +@@ -336,17 +339,23 @@ static inline void alias_free_mem_rcu(st + call_rcu(&fa->rcu, __alias_free_mem); + } + +-static void __leaf_free_rcu(struct rcu_head *head) +-{ +- struct leaf *l = container_of(head, struct leaf, rcu); +- kmem_cache_free(trie_leaf_kmem, l); +-} ++#define TNODE_KMALLOC_MAX \ ++ ilog2((PAGE_SIZE - sizeof(struct tnode)) / sizeof(struct rt_trie_node *)) + +-static inline void free_leaf(struct leaf *l) ++static void __node_free_rcu(struct rcu_head *head) + { +- call_rcu(&l->rcu, __leaf_free_rcu); ++ struct rt_trie_node *n = container_of(head, struct rt_trie_node, rcu); ++ ++ if (IS_LEAF(n)) ++ kmem_cache_free(trie_leaf_kmem, n); ++ else if (n->bits <= TNODE_KMALLOC_MAX) ++ kfree(n); ++ else ++ vfree(n); + } + ++#define node_free(n) call_rcu(&n->rcu, __node_free_rcu) ++ + static inline void free_leaf_info(struct leaf_info *leaf) + { + kfree_rcu(leaf, rcu); +@@ -360,43 +369,24 @@ static struct tnode *tnode_alloc(size_t + return vzalloc(size); + } + +-static void __tnode_free_rcu(struct rcu_head *head) +-{ +- struct tnode *tn = container_of(head, struct tnode, rcu); +- size_t size = sizeof(struct tnode) + +- (sizeof(struct rt_trie_node *) << tn->bits); +- +- if (size <= PAGE_SIZE) +- kfree(tn); +- else +- vfree(tn); +-} +- +-static inline void tnode_free(struct tnode *tn) +-{ +- if (IS_LEAF(tn)) +- free_leaf((struct leaf *) tn); +- else +- call_rcu(&tn->rcu, __tnode_free_rcu); +-} +- + static void tnode_free_safe(struct tnode *tn) + { + BUG_ON(IS_LEAF(tn)); +- tn->tnode_free = tnode_free_head; +- tnode_free_head = tn; +- tnode_free_size += sizeof(struct tnode) + +- (sizeof(struct rt_trie_node *) << tn->bits); ++ tn->rcu.next = tnode_free_head; ++ tnode_free_head = &tn->rcu; + } + + static void tnode_free_flush(void) + { +- struct tnode *tn; ++ struct callback_head *head; ++ ++ while ((head = tnode_free_head)) { ++ struct tnode *tn = container_of(head, struct tnode, rcu); ++ ++ tnode_free_head = head->next; ++ tnode_free_size += offsetof(struct tnode, child[1 << tn->bits]); + +- while ((tn = tnode_free_head)) { +- tnode_free_head = tn->tnode_free; +- tn->tnode_free = NULL; +- tnode_free(tn); ++ node_free(tn); + } + + if (tnode_free_size >= PAGE_SIZE * sync_pages) { +@@ -437,7 +427,7 @@ static struct leaf_info *leaf_info_new(i + + static struct tnode *tnode_new(t_key key, int pos, int bits) + { +- size_t sz = sizeof(struct tnode) + (sizeof(struct rt_trie_node *) << bits); ++ size_t sz = offsetof(struct tnode, child[1 << bits]); + struct tnode *tn = tnode_alloc(sz); + unsigned int shift = pos + bits; + +@@ -666,15 +656,15 @@ no_children: + + static void tnode_clean_free(struct tnode *tn) + { ++ struct rt_trie_node *tofree; + int i; +- struct tnode *tofree; + + for (i = 0; i < tnode_child_length(tn); i++) { +- tofree = (struct tnode *)rtnl_dereference(tn->child[i]); ++ tofree = rtnl_dereference(tn->child[i]); + if (tofree) +- tnode_free(tofree); ++ node_free(tofree); + } +- tnode_free(tn); ++ node_free(tn); + } + + static struct tnode *inflate(struct trie *t, struct tnode *tn) +@@ -717,7 +707,7 @@ static struct tnode *inflate(struct trie + inode->bits - 1); + + if (!right) { +- tnode_free(left); ++ node_free(left); + goto nomem; + } + +@@ -1068,7 +1058,7 @@ static struct list_head *fib_insert_node + li = leaf_info_new(plen); + + if (!li) { +- free_leaf(l); ++ node_free(l); + return NULL; + } + +@@ -1100,7 +1090,7 @@ static struct list_head *fib_insert_node + + if (!tn) { + free_leaf_info(li); +- free_leaf(l); ++ node_free(l); + return NULL; + } + +@@ -1580,7 +1570,7 @@ static void trie_leaf_remove(struct trie + } else + RCU_INIT_POINTER(t->trie, NULL); + +- free_leaf(l); ++ node_free(l); + } + + /* diff --git a/target/linux/generic/patches-3.18/080-05-fib_trie-Merge-leaf-into-tnode.patch b/target/linux/generic/patches-3.18/080-05-fib_trie-Merge-leaf-into-tnode.patch new file mode 100644 index 0000000000..20268f51c8 --- /dev/null +++ b/target/linux/generic/patches-3.18/080-05-fib_trie-Merge-leaf-into-tnode.patch @@ -0,0 +1,928 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Wed, 31 Dec 2014 10:55:47 -0800 +Subject: [PATCH] fib_trie: Merge leaf into tnode + +This change makes it so that leaf and tnode are the same struct. As a +result there is no need for rt_trie_node anymore since everyting can be +merged into tnode. + +On 32b systems this results in the leaf being 4 bytes larger, however I +don't know if that is really an issue as this and an eariler patch that +added bits & pos have increased the size from 20 to 28. If I am not +mistaken slub/slab allocate on power of 2 sizes so 20 was likely being +rounded up to 32 anyway. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -96,32 +96,16 @@ struct tnode { + unsigned char pos; /* 2log(KEYLENGTH) bits needed */ + struct tnode __rcu *parent; + struct rcu_head rcu; +- /* everything above this comment must be the same as rt_trie_node */ +- unsigned int full_children; /* KEYLENGTH bits needed */ +- unsigned int empty_children; /* KEYLENGTH bits needed */ +- struct rt_trie_node __rcu *child[0]; +-}; +- +-/* This struct represents the shared bits between tnode and leaf. If any +- * ordering is changed here is must also be updated in tnode and leaf as +- * well. +- */ +-struct rt_trie_node { +- t_key key; +- unsigned char bits; +- unsigned char pos; +- struct tnode __rcu *parent; +- struct rcu_head rcu; +-}; +- +-struct leaf { +- t_key key; +- unsigned char bits; +- unsigned char pos; +- struct tnode __rcu *parent; +- struct rcu_head rcu; +- /* everything above this comment must be the same as rt_trie_node */ +- struct hlist_head list; ++ union { ++ /* The fields in this struct are valid if bits > 0 (TNODE) */ ++ struct { ++ unsigned int full_children; /* KEYLENGTH bits needed */ ++ unsigned int empty_children; /* KEYLENGTH bits needed */ ++ struct tnode __rcu *child[0]; ++ }; ++ /* This list pointer if valid if bits == 0 (LEAF) */ ++ struct hlist_head list; ++ }; + }; + + struct leaf_info { +@@ -154,15 +138,15 @@ struct trie_stat { + }; + + struct trie { +- struct rt_trie_node __rcu *trie; ++ struct tnode __rcu *trie; + #ifdef CONFIG_IP_FIB_TRIE_STATS + struct trie_use_stats __percpu *stats; + #endif + }; + +-static void tnode_put_child_reorg(struct tnode *tn, int i, struct rt_trie_node *n, ++static void tnode_put_child_reorg(struct tnode *tn, int i, struct tnode *n, + int wasfull); +-static struct rt_trie_node *resize(struct trie *t, struct tnode *tn); ++static struct tnode *resize(struct trie *t, struct tnode *tn); + static struct tnode *inflate(struct trie *t, struct tnode *tn); + static struct tnode *halve(struct trie *t, struct tnode *tn); + /* tnodes to free after resize(); protected by RTNL */ +@@ -186,10 +170,10 @@ static struct kmem_cache *trie_leaf_kmem + #define node_parent_rcu(n) rcu_dereference_rtnl((n)->parent) + + /* wrapper for rcu_assign_pointer */ +-static inline void node_set_parent(struct rt_trie_node *node, struct tnode *ptr) ++static inline void node_set_parent(struct tnode *n, struct tnode *tp) + { +- if (node) +- rcu_assign_pointer(node->parent, ptr); ++ if (n) ++ rcu_assign_pointer(n->parent, tp); + } + + #define NODE_INIT_PARENT(n, p) RCU_INIT_POINTER((n)->parent, p) +@@ -205,7 +189,7 @@ static inline int tnode_child_length(con + /* + * caller must hold RTNL + */ +-static inline struct rt_trie_node *tnode_get_child(const struct tnode *tn, unsigned int i) ++static inline struct tnode *tnode_get_child(const struct tnode *tn, unsigned int i) + { + BUG_ON(i >= tnode_child_length(tn)); + +@@ -215,7 +199,7 @@ static inline struct rt_trie_node *tnode + /* + * caller must hold RCU read lock or RTNL + */ +-static inline struct rt_trie_node *tnode_get_child_rcu(const struct tnode *tn, unsigned int i) ++static inline struct tnode *tnode_get_child_rcu(const struct tnode *tn, unsigned int i) + { + BUG_ON(i >= tnode_child_length(tn)); + +@@ -340,11 +324,11 @@ static inline void alias_free_mem_rcu(st + } + + #define TNODE_KMALLOC_MAX \ +- ilog2((PAGE_SIZE - sizeof(struct tnode)) / sizeof(struct rt_trie_node *)) ++ ilog2((PAGE_SIZE - sizeof(struct tnode)) / sizeof(struct tnode *)) + + static void __node_free_rcu(struct rcu_head *head) + { +- struct rt_trie_node *n = container_of(head, struct rt_trie_node, rcu); ++ struct tnode *n = container_of(head, struct tnode, rcu); + + if (IS_LEAF(n)) + kmem_cache_free(trie_leaf_kmem, n); +@@ -395,9 +379,9 @@ static void tnode_free_flush(void) + } + } + +-static struct leaf *leaf_new(t_key key) ++static struct tnode *leaf_new(t_key key) + { +- struct leaf *l = kmem_cache_alloc(trie_leaf_kmem, GFP_KERNEL); ++ struct tnode *l = kmem_cache_alloc(trie_leaf_kmem, GFP_KERNEL); + if (l) { + l->parent = NULL; + /* set key and pos to reflect full key value +@@ -444,7 +428,7 @@ static struct tnode *tnode_new(t_key key + } + + pr_debug("AT %p s=%zu %zu\n", tn, sizeof(struct tnode), +- sizeof(struct rt_trie_node *) << bits); ++ sizeof(struct tnode *) << bits); + return tn; + } + +@@ -453,13 +437,13 @@ static struct tnode *tnode_new(t_key key + * and no bits are skipped. See discussion in dyntree paper p. 6 + */ + +-static inline int tnode_full(const struct tnode *tn, const struct rt_trie_node *n) ++static inline int tnode_full(const struct tnode *tn, const struct tnode *n) + { + return n && IS_TNODE(n) && (n->pos == (tn->pos + tn->bits)); + } + + static inline void put_child(struct tnode *tn, int i, +- struct rt_trie_node *n) ++ struct tnode *n) + { + tnode_put_child_reorg(tn, i, n, -1); + } +@@ -469,10 +453,10 @@ static inline void put_child(struct tnod + * Update the value of full_children and empty_children. + */ + +-static void tnode_put_child_reorg(struct tnode *tn, int i, struct rt_trie_node *n, ++static void tnode_put_child_reorg(struct tnode *tn, int i, struct tnode *n, + int wasfull) + { +- struct rt_trie_node *chi = rtnl_dereference(tn->child[i]); ++ struct tnode *chi = rtnl_dereference(tn->child[i]); + int isfull; + + BUG_ON(i >= 1<<tn->bits); +@@ -499,10 +483,9 @@ static void tnode_put_child_reorg(struct + } + + #define MAX_WORK 10 +-static struct rt_trie_node *resize(struct trie *t, struct tnode *tn) ++static struct tnode *resize(struct trie *t, struct tnode *tn) + { +- struct rt_trie_node *n = NULL; +- struct tnode *old_tn; ++ struct tnode *old_tn, *n = NULL; + int inflate_threshold_use; + int halve_threshold_use; + int max_work; +@@ -614,7 +597,7 @@ static struct rt_trie_node *resize(struc + + /* Return if at least one inflate is run */ + if (max_work != MAX_WORK) +- return (struct rt_trie_node *) tn; ++ return tn; + + /* + * Halve as long as the number of empty children in this +@@ -650,13 +633,13 @@ no_children: + tnode_free_safe(tn); + return n; + } +- return (struct rt_trie_node *) tn; ++ return tn; + } + + + static void tnode_clean_free(struct tnode *tn) + { +- struct rt_trie_node *tofree; ++ struct tnode *tofree; + int i; + + for (i = 0; i < tnode_child_length(tn); i++) { +@@ -667,10 +650,10 @@ static void tnode_clean_free(struct tnod + node_free(tn); + } + +-static struct tnode *inflate(struct trie *t, struct tnode *tn) ++static struct tnode *inflate(struct trie *t, struct tnode *oldtnode) + { +- struct tnode *oldtnode = tn; +- int olen = tnode_child_length(tn); ++ int olen = tnode_child_length(oldtnode); ++ struct tnode *tn; + int i; + + pr_debug("In inflate\n"); +@@ -690,11 +673,8 @@ static struct tnode *inflate(struct trie + for (i = 0; i < olen; i++) { + struct tnode *inode; + +- inode = (struct tnode *) tnode_get_child(oldtnode, i); +- if (inode && +- IS_TNODE(inode) && +- inode->pos == oldtnode->pos + oldtnode->bits && +- inode->bits > 1) { ++ inode = tnode_get_child(oldtnode, i); ++ if (tnode_full(oldtnode, inode) && inode->bits > 1) { + struct tnode *left, *right; + t_key m = ~0U << (KEYLENGTH - 1) >> inode->pos; + +@@ -711,33 +691,29 @@ static struct tnode *inflate(struct trie + goto nomem; + } + +- put_child(tn, 2*i, (struct rt_trie_node *) left); +- put_child(tn, 2*i+1, (struct rt_trie_node *) right); ++ put_child(tn, 2*i, left); ++ put_child(tn, 2*i+1, right); + } + } + + for (i = 0; i < olen; i++) { +- struct tnode *inode; +- struct rt_trie_node *node = tnode_get_child(oldtnode, i); ++ struct tnode *inode = tnode_get_child(oldtnode, i); + struct tnode *left, *right; + int size, j; + + /* An empty child */ +- if (node == NULL) ++ if (inode == NULL) + continue; + + /* A leaf or an internal node with skipped bits */ +- +- if (IS_LEAF(node) || (node->pos > (tn->pos + tn->bits - 1))) { ++ if (!tnode_full(oldtnode, inode)) { + put_child(tn, +- tkey_extract_bits(node->key, oldtnode->pos, oldtnode->bits + 1), +- node); ++ tkey_extract_bits(inode->key, tn->pos, tn->bits), ++ inode); + continue; + } + + /* An internal node with two children */ +- inode = (struct tnode *) node; +- + if (inode->bits == 1) { + put_child(tn, 2*i, rtnl_dereference(inode->child[0])); + put_child(tn, 2*i+1, rtnl_dereference(inode->child[1])); +@@ -769,12 +745,12 @@ static struct tnode *inflate(struct trie + * bit to zero. + */ + +- left = (struct tnode *) tnode_get_child(tn, 2*i); ++ left = tnode_get_child(tn, 2*i); + put_child(tn, 2*i, NULL); + + BUG_ON(!left); + +- right = (struct tnode *) tnode_get_child(tn, 2*i+1); ++ right = tnode_get_child(tn, 2*i+1); + put_child(tn, 2*i+1, NULL); + + BUG_ON(!right); +@@ -796,12 +772,11 @@ nomem: + return ERR_PTR(-ENOMEM); + } + +-static struct tnode *halve(struct trie *t, struct tnode *tn) ++static struct tnode *halve(struct trie *t, struct tnode *oldtnode) + { +- struct tnode *oldtnode = tn; +- struct rt_trie_node *left, *right; ++ int olen = tnode_child_length(oldtnode); ++ struct tnode *tn, *left, *right; + int i; +- int olen = tnode_child_length(tn); + + pr_debug("In halve\n"); + +@@ -830,7 +805,7 @@ static struct tnode *halve(struct trie * + if (!newn) + goto nomem; + +- put_child(tn, i/2, (struct rt_trie_node *)newn); ++ put_child(tn, i/2, newn); + } + + } +@@ -855,7 +830,7 @@ static struct tnode *halve(struct trie * + } + + /* Two nonempty children */ +- newBinNode = (struct tnode *) tnode_get_child(tn, i/2); ++ newBinNode = tnode_get_child(tn, i/2); + put_child(tn, i/2, NULL); + put_child(newBinNode, 0, left); + put_child(newBinNode, 1, right); +@@ -871,7 +846,7 @@ nomem: + /* readside must use rcu_read_lock currently dump routines + via get_fa_head and dump */ + +-static struct leaf_info *find_leaf_info(struct leaf *l, int plen) ++static struct leaf_info *find_leaf_info(struct tnode *l, int plen) + { + struct hlist_head *head = &l->list; + struct leaf_info *li; +@@ -883,7 +858,7 @@ static struct leaf_info *find_leaf_info( + return NULL; + } + +-static inline struct list_head *get_fa_head(struct leaf *l, int plen) ++static inline struct list_head *get_fa_head(struct tnode *l, int plen) + { + struct leaf_info *li = find_leaf_info(l, plen); + +@@ -915,32 +890,25 @@ static void insert_leaf_info(struct hlis + + /* rcu_read_lock needs to be hold by caller from readside */ + +-static struct leaf * +-fib_find_node(struct trie *t, u32 key) ++static struct tnode *fib_find_node(struct trie *t, u32 key) + { +- int pos; +- struct tnode *tn; +- struct rt_trie_node *n; +- +- pos = 0; +- n = rcu_dereference_rtnl(t->trie); ++ struct tnode *n = rcu_dereference_rtnl(t->trie); ++ int pos = 0; + + while (n && IS_TNODE(n)) { +- tn = (struct tnode *) n; +- +- if (tkey_sub_equals(tn->key, pos, tn->pos-pos, key)) { +- pos = tn->pos + tn->bits; +- n = tnode_get_child_rcu(tn, ++ if (tkey_sub_equals(n->key, pos, n->pos-pos, key)) { ++ pos = n->pos + n->bits; ++ n = tnode_get_child_rcu(n, + tkey_extract_bits(key, +- tn->pos, +- tn->bits)); ++ n->pos, ++ n->bits)); + } else + break; + } + /* Case we have found a leaf. Compare prefixes */ + + if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key)) +- return (struct leaf *)n; ++ return n; + + return NULL; + } +@@ -956,14 +924,13 @@ static void trie_rebalance(struct trie * + while (tn != NULL && (tp = node_parent(tn)) != NULL) { + cindex = tkey_extract_bits(key, tp->pos, tp->bits); + wasfull = tnode_full(tp, tnode_get_child(tp, cindex)); +- tn = (struct tnode *)resize(t, tn); ++ tn = resize(t, tn); + +- tnode_put_child_reorg(tp, cindex, +- (struct rt_trie_node *)tn, wasfull); ++ tnode_put_child_reorg(tp, cindex, tn, wasfull); + + tp = node_parent(tn); + if (!tp) +- rcu_assign_pointer(t->trie, (struct rt_trie_node *)tn); ++ rcu_assign_pointer(t->trie, tn); + + tnode_free_flush(); + if (!tp) +@@ -973,9 +940,9 @@ static void trie_rebalance(struct trie * + + /* Handle last (top) tnode */ + if (IS_TNODE(tn)) +- tn = (struct tnode *)resize(t, tn); ++ tn = resize(t, tn); + +- rcu_assign_pointer(t->trie, (struct rt_trie_node *)tn); ++ rcu_assign_pointer(t->trie, tn); + tnode_free_flush(); + } + +@@ -985,8 +952,8 @@ static struct list_head *fib_insert_node + { + int pos, newpos; + struct tnode *tp = NULL, *tn = NULL; +- struct rt_trie_node *n; +- struct leaf *l; ++ struct tnode *n; ++ struct tnode *l; + int missbit; + struct list_head *fa_head = NULL; + struct leaf_info *li; +@@ -1014,17 +981,15 @@ static struct list_head *fib_insert_node + */ + + while (n && IS_TNODE(n)) { +- tn = (struct tnode *) n; +- +- if (tkey_sub_equals(tn->key, pos, tn->pos-pos, key)) { +- tp = tn; +- pos = tn->pos + tn->bits; +- n = tnode_get_child(tn, ++ if (tkey_sub_equals(n->key, pos, n->pos-pos, key)) { ++ tp = n; ++ pos = n->pos + n->bits; ++ n = tnode_get_child(n, + tkey_extract_bits(key, +- tn->pos, +- tn->bits)); ++ n->pos, ++ n->bits)); + +- BUG_ON(n && node_parent(n) != tn); ++ BUG_ON(n && node_parent(n) != tp); + } else + break; + } +@@ -1040,14 +1005,13 @@ static struct list_head *fib_insert_node + /* Case 1: n is a leaf. Compare prefixes */ + + if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key)) { +- l = (struct leaf *) n; + li = leaf_info_new(plen); + + if (!li) + return NULL; + + fa_head = &li->falh; +- insert_leaf_info(&l->list, li); ++ insert_leaf_info(&n->list, li); + goto done; + } + l = leaf_new(key); +@@ -1068,10 +1032,10 @@ static struct list_head *fib_insert_node + if (t->trie && n == NULL) { + /* Case 2: n is NULL, and will just insert a new leaf */ + +- node_set_parent((struct rt_trie_node *)l, tp); ++ node_set_parent(l, tp); + + cindex = tkey_extract_bits(key, tp->pos, tp->bits); +- put_child(tp, cindex, (struct rt_trie_node *)l); ++ put_child(tp, cindex, l); + } else { + /* Case 3: n is a LEAF or a TNODE and the key doesn't match. */ + /* +@@ -1094,17 +1058,17 @@ static struct list_head *fib_insert_node + return NULL; + } + +- node_set_parent((struct rt_trie_node *)tn, tp); ++ node_set_parent(tn, tp); + + missbit = tkey_extract_bits(key, newpos, 1); +- put_child(tn, missbit, (struct rt_trie_node *)l); ++ put_child(tn, missbit, l); + put_child(tn, 1-missbit, n); + + if (tp) { + cindex = tkey_extract_bits(key, tp->pos, tp->bits); +- put_child(tp, cindex, (struct rt_trie_node *)tn); ++ put_child(tp, cindex, tn); + } else { +- rcu_assign_pointer(t->trie, (struct rt_trie_node *)tn); ++ rcu_assign_pointer(t->trie, tn); + } + + tp = tn; +@@ -1134,7 +1098,7 @@ int fib_table_insert(struct fib_table *t + u8 tos = cfg->fc_tos; + u32 key, mask; + int err; +- struct leaf *l; ++ struct tnode *l; + + if (plen > 32) + return -EINVAL; +@@ -1292,7 +1256,7 @@ err: + } + + /* should be called with rcu_read_lock */ +-static int check_leaf(struct fib_table *tb, struct trie *t, struct leaf *l, ++static int check_leaf(struct fib_table *tb, struct trie *t, struct tnode *l, + t_key key, const struct flowi4 *flp, + struct fib_result *res, int fib_flags) + { +@@ -1365,7 +1329,7 @@ int fib_table_lookup(struct fib_table *t + struct trie_use_stats __percpu *stats = t->stats; + #endif + int ret; +- struct rt_trie_node *n; ++ struct tnode *n; + struct tnode *pn; + unsigned int pos, bits; + t_key key = ntohl(flp->daddr); +@@ -1387,11 +1351,11 @@ int fib_table_lookup(struct fib_table *t + + /* Just a leaf? */ + if (IS_LEAF(n)) { +- ret = check_leaf(tb, t, (struct leaf *)n, key, flp, res, fib_flags); ++ ret = check_leaf(tb, t, n, key, flp, res, fib_flags); + goto found; + } + +- pn = (struct tnode *) n; ++ pn = n; + chopped_off = 0; + + while (pn) { +@@ -1412,13 +1376,13 @@ int fib_table_lookup(struct fib_table *t + } + + if (IS_LEAF(n)) { +- ret = check_leaf(tb, t, (struct leaf *)n, key, flp, res, fib_flags); ++ ret = check_leaf(tb, t, n, key, flp, res, fib_flags); + if (ret > 0) + goto backtrace; + goto found; + } + +- cn = (struct tnode *)n; ++ cn = n; + + /* + * It's a tnode, and we can do some extra checks here if we +@@ -1506,7 +1470,7 @@ int fib_table_lookup(struct fib_table *t + current_prefix_length = mp; + } + +- pn = (struct tnode *)n; /* Descend */ ++ pn = n; /* Descend */ + chopped_off = 0; + continue; + +@@ -1557,7 +1521,7 @@ EXPORT_SYMBOL_GPL(fib_table_lookup); + /* + * Remove the leaf and return parent. + */ +-static void trie_leaf_remove(struct trie *t, struct leaf *l) ++static void trie_leaf_remove(struct trie *t, struct tnode *l) + { + struct tnode *tp = node_parent(l); + +@@ -1584,7 +1548,7 @@ int fib_table_delete(struct fib_table *t + u8 tos = cfg->fc_tos; + struct fib_alias *fa, *fa_to_delete; + struct list_head *fa_head; +- struct leaf *l; ++ struct tnode *l; + struct leaf_info *li; + + if (plen > 32) +@@ -1682,7 +1646,7 @@ static int trie_flush_list(struct list_h + return found; + } + +-static int trie_flush_leaf(struct leaf *l) ++static int trie_flush_leaf(struct tnode *l) + { + int found = 0; + struct hlist_head *lih = &l->list; +@@ -1704,7 +1668,7 @@ static int trie_flush_leaf(struct leaf * + * Scan for the next right leaf starting at node p->child[idx] + * Since we have back pointer, no recursion necessary. + */ +-static struct leaf *leaf_walk_rcu(struct tnode *p, struct rt_trie_node *c) ++static struct tnode *leaf_walk_rcu(struct tnode *p, struct tnode *c) + { + do { + t_key idx; +@@ -1720,47 +1684,46 @@ static struct leaf *leaf_walk_rcu(struct + continue; + + if (IS_LEAF(c)) +- return (struct leaf *) c; ++ return c; + + /* Rescan start scanning in new node */ +- p = (struct tnode *) c; ++ p = c; + idx = 0; + } + + /* Node empty, walk back up to parent */ +- c = (struct rt_trie_node *) p; ++ c = p; + } while ((p = node_parent_rcu(c)) != NULL); + + return NULL; /* Root of trie */ + } + +-static struct leaf *trie_firstleaf(struct trie *t) ++static struct tnode *trie_firstleaf(struct trie *t) + { +- struct tnode *n = (struct tnode *)rcu_dereference_rtnl(t->trie); ++ struct tnode *n = rcu_dereference_rtnl(t->trie); + + if (!n) + return NULL; + + if (IS_LEAF(n)) /* trie is just a leaf */ +- return (struct leaf *) n; ++ return n; + + return leaf_walk_rcu(n, NULL); + } + +-static struct leaf *trie_nextleaf(struct leaf *l) ++static struct tnode *trie_nextleaf(struct tnode *l) + { +- struct rt_trie_node *c = (struct rt_trie_node *) l; +- struct tnode *p = node_parent_rcu(c); ++ struct tnode *p = node_parent_rcu(l); + + if (!p) + return NULL; /* trie with just one leaf */ + +- return leaf_walk_rcu(p, c); ++ return leaf_walk_rcu(p, l); + } + +-static struct leaf *trie_leafindex(struct trie *t, int index) ++static struct tnode *trie_leafindex(struct trie *t, int index) + { +- struct leaf *l = trie_firstleaf(t); ++ struct tnode *l = trie_firstleaf(t); + + while (l && index-- > 0) + l = trie_nextleaf(l); +@@ -1775,7 +1738,7 @@ static struct leaf *trie_leafindex(struc + int fib_table_flush(struct fib_table *tb) + { + struct trie *t = (struct trie *) tb->tb_data; +- struct leaf *l, *ll = NULL; ++ struct tnode *l, *ll = NULL; + int found = 0; + + for (l = trie_firstleaf(t); l; l = trie_nextleaf(l)) { +@@ -1840,7 +1803,7 @@ static int fn_trie_dump_fa(t_key key, in + return skb->len; + } + +-static int fn_trie_dump_leaf(struct leaf *l, struct fib_table *tb, ++static int fn_trie_dump_leaf(struct tnode *l, struct fib_table *tb, + struct sk_buff *skb, struct netlink_callback *cb) + { + struct leaf_info *li; +@@ -1876,7 +1839,7 @@ static int fn_trie_dump_leaf(struct leaf + int fib_table_dump(struct fib_table *tb, struct sk_buff *skb, + struct netlink_callback *cb) + { +- struct leaf *l; ++ struct tnode *l; + struct trie *t = (struct trie *) tb->tb_data; + t_key key = cb->args[2]; + int count = cb->args[3]; +@@ -1922,7 +1885,7 @@ void __init fib_trie_init(void) + 0, SLAB_PANIC, NULL); + + trie_leaf_kmem = kmem_cache_create("ip_fib_trie", +- max(sizeof(struct leaf), ++ max(sizeof(struct tnode), + sizeof(struct leaf_info)), + 0, SLAB_PANIC, NULL); + } +@@ -1965,7 +1928,7 @@ struct fib_trie_iter { + unsigned int depth; + }; + +-static struct rt_trie_node *fib_trie_get_next(struct fib_trie_iter *iter) ++static struct tnode *fib_trie_get_next(struct fib_trie_iter *iter) + { + struct tnode *tn = iter->tnode; + unsigned int cindex = iter->index; +@@ -1979,7 +1942,7 @@ static struct rt_trie_node *fib_trie_get + iter->tnode, iter->index, iter->depth); + rescan: + while (cindex < (1<<tn->bits)) { +- struct rt_trie_node *n = tnode_get_child_rcu(tn, cindex); ++ struct tnode *n = tnode_get_child_rcu(tn, cindex); + + if (n) { + if (IS_LEAF(n)) { +@@ -1987,7 +1950,7 @@ rescan: + iter->index = cindex + 1; + } else { + /* push down one level */ +- iter->tnode = (struct tnode *) n; ++ iter->tnode = n; + iter->index = 0; + ++iter->depth; + } +@@ -1998,7 +1961,7 @@ rescan: + } + + /* Current node exhausted, pop back up */ +- p = node_parent_rcu((struct rt_trie_node *)tn); ++ p = node_parent_rcu(tn); + if (p) { + cindex = tkey_extract_bits(tn->key, p->pos, p->bits)+1; + tn = p; +@@ -2010,10 +1973,10 @@ rescan: + return NULL; + } + +-static struct rt_trie_node *fib_trie_get_first(struct fib_trie_iter *iter, ++static struct tnode *fib_trie_get_first(struct fib_trie_iter *iter, + struct trie *t) + { +- struct rt_trie_node *n; ++ struct tnode *n; + + if (!t) + return NULL; +@@ -2023,7 +1986,7 @@ static struct rt_trie_node *fib_trie_get + return NULL; + + if (IS_TNODE(n)) { +- iter->tnode = (struct tnode *) n; ++ iter->tnode = n; + iter->index = 0; + iter->depth = 1; + } else { +@@ -2037,7 +2000,7 @@ static struct rt_trie_node *fib_trie_get + + static void trie_collect_stats(struct trie *t, struct trie_stat *s) + { +- struct rt_trie_node *n; ++ struct tnode *n; + struct fib_trie_iter iter; + + memset(s, 0, sizeof(*s)); +@@ -2045,7 +2008,6 @@ static void trie_collect_stats(struct tr + rcu_read_lock(); + for (n = fib_trie_get_first(&iter, t); n; n = fib_trie_get_next(&iter)) { + if (IS_LEAF(n)) { +- struct leaf *l = (struct leaf *)n; + struct leaf_info *li; + + s->leaves++; +@@ -2053,18 +2015,17 @@ static void trie_collect_stats(struct tr + if (iter.depth > s->maxdepth) + s->maxdepth = iter.depth; + +- hlist_for_each_entry_rcu(li, &l->list, hlist) ++ hlist_for_each_entry_rcu(li, &n->list, hlist) + ++s->prefixes; + } else { +- const struct tnode *tn = (const struct tnode *) n; + int i; + + s->tnodes++; +- if (tn->bits < MAX_STAT_DEPTH) +- s->nodesizes[tn->bits]++; ++ if (n->bits < MAX_STAT_DEPTH) ++ s->nodesizes[n->bits]++; + +- for (i = 0; i < (1<<tn->bits); i++) +- if (!tn->child[i]) ++ for (i = 0; i < tnode_child_length(n); i++) ++ if (!rcu_access_pointer(n->child[i])) + s->nullpointers++; + } + } +@@ -2088,7 +2049,7 @@ static void trie_show_stats(struct seq_f + seq_printf(seq, "\tMax depth: %u\n", stat->maxdepth); + + seq_printf(seq, "\tLeaves: %u\n", stat->leaves); +- bytes = sizeof(struct leaf) * stat->leaves; ++ bytes = sizeof(struct tnode) * stat->leaves; + + seq_printf(seq, "\tPrefixes: %u\n", stat->prefixes); + bytes += sizeof(struct leaf_info) * stat->prefixes; +@@ -2109,7 +2070,7 @@ static void trie_show_stats(struct seq_f + seq_putc(seq, '\n'); + seq_printf(seq, "\tPointers: %u\n", pointers); + +- bytes += sizeof(struct rt_trie_node *) * pointers; ++ bytes += sizeof(struct tnode *) * pointers; + seq_printf(seq, "Null ptrs: %u\n", stat->nullpointers); + seq_printf(seq, "Total size: %u kB\n", (bytes + 1023) / 1024); + } +@@ -2163,7 +2124,7 @@ static int fib_triestat_seq_show(struct + seq_printf(seq, + "Basic info: size of leaf:" + " %Zd bytes, size of tnode: %Zd bytes.\n", +- sizeof(struct leaf), sizeof(struct tnode)); ++ sizeof(struct tnode), sizeof(struct tnode)); + + for (h = 0; h < FIB_TABLE_HASHSZ; h++) { + struct hlist_head *head = &net->ipv4.fib_table_hash[h]; +@@ -2202,7 +2163,7 @@ static const struct file_operations fib_ + .release = single_release_net, + }; + +-static struct rt_trie_node *fib_trie_get_idx(struct seq_file *seq, loff_t pos) ++static struct tnode *fib_trie_get_idx(struct seq_file *seq, loff_t pos) + { + struct fib_trie_iter *iter = seq->private; + struct net *net = seq_file_net(seq); +@@ -2214,7 +2175,7 @@ static struct rt_trie_node *fib_trie_get + struct fib_table *tb; + + hlist_for_each_entry_rcu(tb, head, tb_hlist) { +- struct rt_trie_node *n; ++ struct tnode *n; + + for (n = fib_trie_get_first(iter, + (struct trie *) tb->tb_data); +@@ -2243,7 +2204,7 @@ static void *fib_trie_seq_next(struct se + struct fib_table *tb = iter->tb; + struct hlist_node *tb_node; + unsigned int h; +- struct rt_trie_node *n; ++ struct tnode *n; + + ++*pos; + /* next node in same table */ +@@ -2330,29 +2291,26 @@ static inline const char *rtn_type(char + static int fib_trie_seq_show(struct seq_file *seq, void *v) + { + const struct fib_trie_iter *iter = seq->private; +- struct rt_trie_node *n = v; ++ struct tnode *n = v; + + if (!node_parent_rcu(n)) + fib_table_print(seq, iter->tb); + + if (IS_TNODE(n)) { +- struct tnode *tn = (struct tnode *) n; +- __be32 prf = htonl(tn->key); ++ __be32 prf = htonl(n->key); + +- seq_indent(seq, iter->depth-1); ++ seq_indent(seq, iter->depth - 1); + seq_printf(seq, " +-- %pI4/%d %d %d %d\n", +- &prf, tn->pos, tn->bits, tn->full_children, +- tn->empty_children); +- ++ &prf, n->pos, n->bits, n->full_children, ++ n->empty_children); + } else { +- struct leaf *l = (struct leaf *) n; + struct leaf_info *li; +- __be32 val = htonl(l->key); ++ __be32 val = htonl(n->key); + + seq_indent(seq, iter->depth); + seq_printf(seq, " |-- %pI4\n", &val); + +- hlist_for_each_entry_rcu(li, &l->list, hlist) { ++ hlist_for_each_entry_rcu(li, &n->list, hlist) { + struct fib_alias *fa; + + list_for_each_entry_rcu(fa, &li->falh, fa_list) { +@@ -2402,9 +2360,9 @@ struct fib_route_iter { + t_key key; + }; + +-static struct leaf *fib_route_get_idx(struct fib_route_iter *iter, loff_t pos) ++static struct tnode *fib_route_get_idx(struct fib_route_iter *iter, loff_t pos) + { +- struct leaf *l = NULL; ++ struct tnode *l = NULL; + struct trie *t = iter->main_trie; + + /* use cache location of last found key */ +@@ -2449,7 +2407,7 @@ static void *fib_route_seq_start(struct + static void *fib_route_seq_next(struct seq_file *seq, void *v, loff_t *pos) + { + struct fib_route_iter *iter = seq->private; +- struct leaf *l = v; ++ struct tnode *l = v; + + ++*pos; + if (v == SEQ_START_TOKEN) { +@@ -2495,7 +2453,7 @@ static unsigned int fib_flag_trans(int t + */ + static int fib_route_seq_show(struct seq_file *seq, void *v) + { +- struct leaf *l = v; ++ struct tnode *l = v; + struct leaf_info *li; + + if (v == SEQ_START_TOKEN) { diff --git a/target/linux/generic/patches-3.18/080-06-fib_trie-Optimize-fib_table_lookup-to-avoid-wasting-.patch b/target/linux/generic/patches-3.18/080-06-fib_trie-Optimize-fib_table_lookup-to-avoid-wasting-.patch new file mode 100644 index 0000000000..13004a1c31 --- /dev/null +++ b/target/linux/generic/patches-3.18/080-06-fib_trie-Optimize-fib_table_lookup-to-avoid-wasting-.patch @@ -0,0 +1,343 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Wed, 31 Dec 2014 10:55:54 -0800 +Subject: [PATCH] fib_trie: Optimize fib_table_lookup to avoid wasting + time on loops/variables + +This patch is meant to reduce the complexity of fib_table_lookup by reducing +the number of variables to the bare minimum while still keeping the same if +not improved functionality versus the original. + +Most of this change was started off by the desire to rid the function of +chopped_off and current_prefix_length as they actually added very little to +the function since they only applied when computing the cindex. I was able +to replace them mostly with just a check for the prefix match. As long as +the prefix between the key and the node being tested was the same we know +we can search the tnode fully versus just testing cindex 0. + +The second portion of the change ended up being a massive reordering. +Originally the calls to check_leaf were up near the start of the loop, and +the backtracing and descending into lower levels of tnodes was later. This +didn't make much sense as the structure of the tree means the leaves are +always the last thing to be tested. As such I reordered things so that we +instead have a loop that will delve into the tree and only exit when we +have either found a leaf or we have exhausted the tree. The advantage of +rearranging things like this is that we can fully inline check_leaf since +there is now only one reference to it in the function. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -90,6 +90,9 @@ typedef unsigned int t_key; + #define IS_TNODE(n) ((n)->bits) + #define IS_LEAF(n) (!(n)->bits) + ++#define get_shift(_kv) (KEYLENGTH - (_kv)->pos - (_kv)->bits) ++#define get_index(_key, _kv) (((_key) ^ (_kv)->key) >> get_shift(_kv)) ++ + struct tnode { + t_key key; + unsigned char bits; /* 2log(KEYLENGTH) bits needed */ +@@ -1281,7 +1284,7 @@ static int check_leaf(struct fib_table * + continue; + fib_alias_accessed(fa); + err = fib_props[fa->fa_type].error; +- if (err) { ++ if (unlikely(err < 0)) { + #ifdef CONFIG_IP_FIB_TRIE_STATS + this_cpu_inc(t->stats->semantic_match_passed); + #endif +@@ -1303,7 +1306,7 @@ static int check_leaf(struct fib_table * + res->prefixlen = li->plen; + res->nh_sel = nhsel; + res->type = fa->fa_type; +- res->scope = fa->fa_info->fib_scope; ++ res->scope = fi->fib_scope; + res->fi = fi; + res->table = tb; + res->fa_head = &li->falh; +@@ -1321,23 +1324,24 @@ static int check_leaf(struct fib_table * + return 1; + } + ++static inline t_key prefix_mismatch(t_key key, struct tnode *n) ++{ ++ t_key prefix = n->key; ++ ++ return (key ^ prefix) & (prefix | -prefix); ++} ++ + int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp, + struct fib_result *res, int fib_flags) + { +- struct trie *t = (struct trie *) tb->tb_data; ++ struct trie *t = (struct trie *)tb->tb_data; + #ifdef CONFIG_IP_FIB_TRIE_STATS + struct trie_use_stats __percpu *stats = t->stats; + #endif +- int ret; +- struct tnode *n; +- struct tnode *pn; +- unsigned int pos, bits; +- t_key key = ntohl(flp->daddr); +- unsigned int chopped_off; +- t_key cindex = 0; +- unsigned int current_prefix_length = KEYLENGTH; +- struct tnode *cn; +- t_key pref_mismatch; ++ const t_key key = ntohl(flp->daddr); ++ struct tnode *n, *pn; ++ t_key cindex; ++ int ret = 1; + + rcu_read_lock(); + +@@ -1349,170 +1353,102 @@ int fib_table_lookup(struct fib_table *t + this_cpu_inc(stats->gets); + #endif + +- /* Just a leaf? */ +- if (IS_LEAF(n)) { +- ret = check_leaf(tb, t, n, key, flp, res, fib_flags); +- goto found; +- } +- + pn = n; +- chopped_off = 0; +- +- while (pn) { +- pos = pn->pos; +- bits = pn->bits; ++ cindex = 0; + +- if (!chopped_off) +- cindex = tkey_extract_bits(mask_pfx(key, current_prefix_length), +- pos, bits); +- +- n = tnode_get_child_rcu(pn, cindex); +- +- if (n == NULL) { +-#ifdef CONFIG_IP_FIB_TRIE_STATS +- this_cpu_inc(stats->null_node_hit); +-#endif +- goto backtrace; +- } ++ /* Step 1: Travel to the longest prefix match in the trie */ ++ for (;;) { ++ unsigned long index = get_index(key, n); ++ ++ /* This bit of code is a bit tricky but it combines multiple ++ * checks into a single check. The prefix consists of the ++ * prefix plus zeros for the "bits" in the prefix. The index ++ * is the difference between the key and this value. From ++ * this we can actually derive several pieces of data. ++ * if !(index >> bits) ++ * we know the value is child index ++ * else ++ * we have a mismatch in skip bits and failed ++ */ ++ if (index >> n->bits) ++ break; + +- if (IS_LEAF(n)) { +- ret = check_leaf(tb, t, n, key, flp, res, fib_flags); +- if (ret > 0) +- goto backtrace; ++ /* we have found a leaf. Prefixes have already been compared */ ++ if (IS_LEAF(n)) + goto found; +- } + +- cn = n; +- +- /* +- * It's a tnode, and we can do some extra checks here if we +- * like, to avoid descending into a dead-end branch. +- * This tnode is in the parent's child array at index +- * key[p_pos..p_pos+p_bits] but potentially with some bits +- * chopped off, so in reality the index may be just a +- * subprefix, padded with zero at the end. +- * We can also take a look at any skipped bits in this +- * tnode - everything up to p_pos is supposed to be ok, +- * and the non-chopped bits of the index (se previous +- * paragraph) are also guaranteed ok, but the rest is +- * considered unknown. +- * +- * The skipped bits are key[pos+bits..cn->pos]. +- */ +- +- /* If current_prefix_length < pos+bits, we are already doing +- * actual prefix matching, which means everything from +- * pos+(bits-chopped_off) onward must be zero along some +- * branch of this subtree - otherwise there is *no* valid +- * prefix present. Here we can only check the skipped +- * bits. Remember, since we have already indexed into the +- * parent's child array, we know that the bits we chopped of +- * *are* zero. ++ /* only record pn and cindex if we are going to be chopping ++ * bits later. Otherwise we are just wasting cycles. + */ +- +- /* NOTA BENE: Checking only skipped bits +- for the new node here */ +- +- if (current_prefix_length < pos+bits) { +- if (tkey_extract_bits(cn->key, current_prefix_length, +- cn->pos - current_prefix_length) +- || !(cn->child[0])) +- goto backtrace; ++ if (index) { ++ pn = n; ++ cindex = index; + } + +- /* +- * If chopped_off=0, the index is fully validated and we +- * only need to look at the skipped bits for this, the new, +- * tnode. What we actually want to do is to find out if +- * these skipped bits match our key perfectly, or if we will +- * have to count on finding a matching prefix further down, +- * because if we do, we would like to have some way of +- * verifying the existence of such a prefix at this point. +- */ +- +- /* The only thing we can do at this point is to verify that +- * any such matching prefix can indeed be a prefix to our +- * key, and if the bits in the node we are inspecting that +- * do not match our key are not ZERO, this cannot be true. +- * Thus, find out where there is a mismatch (before cn->pos) +- * and verify that all the mismatching bits are zero in the +- * new tnode's key. +- */ ++ n = rcu_dereference(n->child[index]); ++ if (unlikely(!n)) ++ goto backtrace; ++ } + +- /* +- * Note: We aren't very concerned about the piece of +- * the key that precede pn->pos+pn->bits, since these +- * have already been checked. The bits after cn->pos +- * aren't checked since these are by definition +- * "unknown" at this point. Thus, what we want to see +- * is if we are about to enter the "prefix matching" +- * state, and in that case verify that the skipped +- * bits that will prevail throughout this subtree are +- * zero, as they have to be if we are to find a +- * matching prefix. ++ /* Step 2: Sort out leaves and begin backtracing for longest prefix */ ++ for (;;) { ++ /* record the pointer where our next node pointer is stored */ ++ struct tnode __rcu **cptr = n->child; ++ ++ /* This test verifies that none of the bits that differ ++ * between the key and the prefix exist in the region of ++ * the lsb and higher in the prefix. + */ ++ if (unlikely(prefix_mismatch(key, n))) ++ goto backtrace; + +- pref_mismatch = mask_pfx(cn->key ^ key, cn->pos); ++ /* exit out and process leaf */ ++ if (unlikely(IS_LEAF(n))) ++ break; + +- /* +- * In short: If skipped bits in this node do not match +- * the search key, enter the "prefix matching" +- * state.directly. ++ /* Don't bother recording parent info. Since we are in ++ * prefix match mode we will have to come back to wherever ++ * we started this traversal anyway + */ +- if (pref_mismatch) { +- /* fls(x) = __fls(x) + 1 */ +- int mp = KEYLENGTH - __fls(pref_mismatch) - 1; +- +- if (tkey_extract_bits(cn->key, mp, cn->pos - mp) != 0) +- goto backtrace; +- +- if (current_prefix_length >= cn->pos) +- current_prefix_length = mp; +- } +- +- pn = n; /* Descend */ +- chopped_off = 0; +- continue; + ++ while ((n = rcu_dereference(*cptr)) == NULL) { + backtrace: +- chopped_off++; +- +- /* As zero don't change the child key (cindex) */ +- while ((chopped_off <= pn->bits) +- && !(cindex & (1<<(chopped_off-1)))) +- chopped_off++; +- +- /* Decrease current_... with bits chopped off */ +- if (current_prefix_length > pn->pos + pn->bits - chopped_off) +- current_prefix_length = pn->pos + pn->bits +- - chopped_off; +- +- /* +- * Either we do the actual chop off according or if we have +- * chopped off all bits in this tnode walk up to our parent. +- */ +- +- if (chopped_off <= pn->bits) { +- cindex &= ~(1 << (chopped_off-1)); +- } else { +- struct tnode *parent = node_parent_rcu(pn); +- if (!parent) +- goto failed; +- +- /* Get Child's index */ +- cindex = tkey_extract_bits(pn->key, parent->pos, parent->bits); +- pn = parent; +- chopped_off = 0; +- + #ifdef CONFIG_IP_FIB_TRIE_STATS +- this_cpu_inc(stats->backtrack); ++ if (!n) ++ this_cpu_inc(stats->null_node_hit); + #endif +- goto backtrace; ++ /* If we are at cindex 0 there are no more bits for ++ * us to strip at this level so we must ascend back ++ * up one level to see if there are any more bits to ++ * be stripped there. ++ */ ++ while (!cindex) { ++ t_key pkey = pn->key; ++ ++ pn = node_parent_rcu(pn); ++ if (unlikely(!pn)) ++ goto failed; ++#ifdef CONFIG_IP_FIB_TRIE_STATS ++ this_cpu_inc(stats->backtrack); ++#endif ++ /* Get Child's index */ ++ cindex = get_index(pkey, pn); ++ } ++ ++ /* strip the least significant bit from the cindex */ ++ cindex &= cindex - 1; ++ ++ /* grab pointer for next child node */ ++ cptr = &pn->child[cindex]; + } + } +-failed: +- ret = 1; ++ + found: ++ /* Step 3: Process the leaf, if that fails fall back to backtracing */ ++ ret = check_leaf(tb, t, n, key, flp, res, fib_flags); ++ if (unlikely(ret > 0)) ++ goto backtrace; ++failed: + rcu_read_unlock(); + return ret; + } diff --git a/target/linux/generic/patches-3.18/080-07-fib_trie-Optimize-fib_find_node.patch b/target/linux/generic/patches-3.18/080-07-fib_trie-Optimize-fib_find_node.patch new file mode 100644 index 0000000000..0193f758f6 --- /dev/null +++ b/target/linux/generic/patches-3.18/080-07-fib_trie-Optimize-fib_find_node.patch @@ -0,0 +1,64 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Wed, 31 Dec 2014 10:56:00 -0800 +Subject: [PATCH] fib_trie: Optimize fib_find_node + +This patch makes use of the same features I made use of for +fib_table_lookup to streamline fib_find_node. The resultant code should be +smaller and run faster than the original. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -892,28 +892,34 @@ static void insert_leaf_info(struct hlis + } + + /* rcu_read_lock needs to be hold by caller from readside */ +- + static struct tnode *fib_find_node(struct trie *t, u32 key) + { + struct tnode *n = rcu_dereference_rtnl(t->trie); +- int pos = 0; + +- while (n && IS_TNODE(n)) { +- if (tkey_sub_equals(n->key, pos, n->pos-pos, key)) { +- pos = n->pos + n->bits; +- n = tnode_get_child_rcu(n, +- tkey_extract_bits(key, +- n->pos, +- n->bits)); +- } else ++ while (n) { ++ unsigned long index = get_index(key, n); ++ ++ /* This bit of code is a bit tricky but it combines multiple ++ * checks into a single check. The prefix consists of the ++ * prefix plus zeros for the bits in the cindex. The index ++ * is the difference between the key and this value. From ++ * this we can actually derive several pieces of data. ++ * if !(index >> bits) ++ * we know the value is cindex ++ * else ++ * we have a mismatch in skip bits and failed ++ */ ++ if (index >> n->bits) ++ return NULL; ++ ++ /* we have found a leaf. Prefixes have already been compared */ ++ if (IS_LEAF(n)) + break; +- } +- /* Case we have found a leaf. Compare prefixes */ + +- if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key)) +- return n; ++ n = rcu_dereference_rtnl(n->child[index]); ++ } + +- return NULL; ++ return n; + } + + static void trie_rebalance(struct trie *t, struct tnode *tn) diff --git a/target/linux/generic/patches-3.18/080-08-fib_trie-Optimize-fib_table_insert.patch b/target/linux/generic/patches-3.18/080-08-fib_trie-Optimize-fib_table_insert.patch new file mode 100644 index 0000000000..dd150ebf33 --- /dev/null +++ b/target/linux/generic/patches-3.18/080-08-fib_trie-Optimize-fib_table_insert.patch @@ -0,0 +1,276 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Wed, 31 Dec 2014 10:56:06 -0800 +Subject: [PATCH] fib_trie: Optimize fib_table_insert + +This patch updates the fib_table_insert function to take advantage of the +changes made to improve the performance of fib_table_lookup. As a result +the code should be smaller and run faster then the original. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -222,31 +222,6 @@ static inline t_key tkey_extract_bits(t_ + return 0; + } + +-static inline int tkey_equals(t_key a, t_key b) +-{ +- return a == b; +-} +- +-static inline int tkey_sub_equals(t_key a, int offset, int bits, t_key b) +-{ +- if (bits == 0 || offset >= KEYLENGTH) +- return 1; +- bits = bits > KEYLENGTH ? KEYLENGTH : bits; +- return ((a ^ b) << offset) >> (KEYLENGTH - bits) == 0; +-} +- +-static inline int tkey_mismatch(t_key a, int offset, t_key b) +-{ +- t_key diff = a ^ b; +- int i = offset; +- +- if (!diff) +- return 0; +- while ((diff << i) >> (KEYLENGTH-1) == 0) +- i++; +- return i; +-} +- + /* + To understand this stuff, an understanding of keys and all their bits is + necessary. Every node in the trie has a key associated with it, but not +@@ -485,6 +460,15 @@ static void tnode_put_child_reorg(struct + rcu_assign_pointer(tn->child[i], n); + } + ++static void put_child_root(struct tnode *tp, struct trie *t, ++ t_key key, struct tnode *n) ++{ ++ if (tp) ++ put_child(tp, get_index(key, tp), n); ++ else ++ rcu_assign_pointer(t->trie, n); ++} ++ + #define MAX_WORK 10 + static struct tnode *resize(struct trie *t, struct tnode *tn) + { +@@ -959,138 +943,100 @@ static void trie_rebalance(struct trie * + + static struct list_head *fib_insert_node(struct trie *t, u32 key, int plen) + { +- int pos, newpos; +- struct tnode *tp = NULL, *tn = NULL; +- struct tnode *n; +- struct tnode *l; +- int missbit; + struct list_head *fa_head = NULL; ++ struct tnode *l, *n, *tp = NULL; + struct leaf_info *li; +- t_key cindex; + +- pos = 0; ++ li = leaf_info_new(plen); ++ if (!li) ++ return NULL; ++ fa_head = &li->falh; ++ + n = rtnl_dereference(t->trie); + + /* If we point to NULL, stop. Either the tree is empty and we should + * just put a new leaf in if, or we have reached an empty child slot, + * and we should just put our new leaf in that. +- * If we point to a T_TNODE, check if it matches our key. Note that +- * a T_TNODE might be skipping any number of bits - its 'pos' need +- * not be the parent's 'pos'+'bits'! + * +- * If it does match the current key, get pos/bits from it, extract +- * the index from our key, push the T_TNODE and walk the tree. +- * +- * If it doesn't, we have to replace it with a new T_TNODE. +- * +- * If we point to a T_LEAF, it might or might not have the same key +- * as we do. If it does, just change the value, update the T_LEAF's +- * value, and return it. +- * If it doesn't, we need to replace it with a T_TNODE. ++ * If we hit a node with a key that does't match then we should stop ++ * and create a new tnode to replace that node and insert ourselves ++ * and the other node into the new tnode. + */ ++ while (n) { ++ unsigned long index = get_index(key, n); + +- while (n && IS_TNODE(n)) { +- if (tkey_sub_equals(n->key, pos, n->pos-pos, key)) { +- tp = n; +- pos = n->pos + n->bits; +- n = tnode_get_child(n, +- tkey_extract_bits(key, +- n->pos, +- n->bits)); +- +- BUG_ON(n && node_parent(n) != tp); +- } else ++ /* This bit of code is a bit tricky but it combines multiple ++ * checks into a single check. The prefix consists of the ++ * prefix plus zeros for the "bits" in the prefix. The index ++ * is the difference between the key and this value. From ++ * this we can actually derive several pieces of data. ++ * if !(index >> bits) ++ * we know the value is child index ++ * else ++ * we have a mismatch in skip bits and failed ++ */ ++ if (index >> n->bits) + break; +- } + +- /* +- * n ----> NULL, LEAF or TNODE +- * +- * tp is n's (parent) ----> NULL or TNODE +- */ +- +- BUG_ON(tp && IS_LEAF(tp)); +- +- /* Case 1: n is a leaf. Compare prefixes */ +- +- if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key)) { +- li = leaf_info_new(plen); +- +- if (!li) +- return NULL; ++ /* we have found a leaf. Prefixes have already been compared */ ++ if (IS_LEAF(n)) { ++ /* Case 1: n is a leaf, and prefixes match*/ ++ insert_leaf_info(&n->list, li); ++ return fa_head; ++ } + +- fa_head = &li->falh; +- insert_leaf_info(&n->list, li); +- goto done; ++ tp = n; ++ n = rcu_dereference_rtnl(n->child[index]); + } +- l = leaf_new(key); +- +- if (!l) +- return NULL; +- +- li = leaf_info_new(plen); + +- if (!li) { +- node_free(l); ++ l = leaf_new(key); ++ if (!l) { ++ free_leaf_info(li); + return NULL; + } + +- fa_head = &li->falh; + insert_leaf_info(&l->list, li); + +- if (t->trie && n == NULL) { +- /* Case 2: n is NULL, and will just insert a new leaf */ +- +- node_set_parent(l, tp); +- +- cindex = tkey_extract_bits(key, tp->pos, tp->bits); +- put_child(tp, cindex, l); +- } else { +- /* Case 3: n is a LEAF or a TNODE and the key doesn't match. */ +- /* +- * Add a new tnode here +- * first tnode need some special handling +- */ ++ /* Case 2: n is a LEAF or a TNODE and the key doesn't match. ++ * ++ * Add a new tnode here ++ * first tnode need some special handling ++ * leaves us in position for handling as case 3 ++ */ ++ if (n) { ++ struct tnode *tn; ++ int newpos; + +- if (n) { +- pos = tp ? tp->pos+tp->bits : 0; +- newpos = tkey_mismatch(key, pos, n->key); +- tn = tnode_new(n->key, newpos, 1); +- } else { +- newpos = 0; +- tn = tnode_new(key, newpos, 1); /* First tnode */ +- } ++ newpos = KEYLENGTH - __fls(n->key ^ key) - 1; + ++ tn = tnode_new(key, newpos, 1); + if (!tn) { + free_leaf_info(li); + node_free(l); + return NULL; + } + +- node_set_parent(tn, tp); +- +- missbit = tkey_extract_bits(key, newpos, 1); +- put_child(tn, missbit, l); +- put_child(tn, 1-missbit, n); +- +- if (tp) { +- cindex = tkey_extract_bits(key, tp->pos, tp->bits); +- put_child(tp, cindex, tn); +- } else { +- rcu_assign_pointer(t->trie, tn); +- } ++ /* initialize routes out of node */ ++ NODE_INIT_PARENT(tn, tp); ++ put_child(tn, get_index(key, tn) ^ 1, n); ++ ++ /* start adding routes into the node */ ++ put_child_root(tp, t, key, tn); ++ node_set_parent(n, tn); + ++ /* parent now has a NULL spot where the leaf can go */ + tp = tn; + } + +- if (tp && tp->pos + tp->bits > 32) +- pr_warn("fib_trie tp=%p pos=%d, bits=%d, key=%0x plen=%d\n", +- tp, tp->pos, tp->bits, key, plen); +- +- /* Rebalance the trie */ ++ /* Case 3: n is NULL, and will just insert a new leaf */ ++ if (tp) { ++ NODE_INIT_PARENT(l, tp); ++ put_child(tp, get_index(key, tp), l); ++ trie_rebalance(t, tp); ++ } else { ++ rcu_assign_pointer(t->trie, l); ++ } + +- trie_rebalance(t, tp); +-done: + return fa_head; + } + +@@ -1470,11 +1416,11 @@ static void trie_leaf_remove(struct trie + pr_debug("entering trie_leaf_remove(%p)\n", l); + + if (tp) { +- t_key cindex = tkey_extract_bits(l->key, tp->pos, tp->bits); +- put_child(tp, cindex, NULL); ++ put_child(tp, get_index(l->key, tp), NULL); + trie_rebalance(t, tp); +- } else ++ } else { + RCU_INIT_POINTER(t->trie, NULL); ++ } + + node_free(l); + } diff --git a/target/linux/generic/patches-3.18/080-09-fib_trie-Update-meaning-of-pos-to-represent-unchecke.patch b/target/linux/generic/patches-3.18/080-09-fib_trie-Update-meaning-of-pos-to-represent-unchecke.patch new file mode 100644 index 0000000000..53761d4207 --- /dev/null +++ b/target/linux/generic/patches-3.18/080-09-fib_trie-Update-meaning-of-pos-to-represent-unchecke.patch @@ -0,0 +1,346 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Wed, 31 Dec 2014 10:56:12 -0800 +Subject: [PATCH] fib_trie: Update meaning of pos to represent unchecked + bits + +This change moves the pos value to the other side of the "bits" field. By +doing this it actually simplifies a significant amount of code in the trie. + +For example when halving a tree we know that the bit lost exists at +oldnode->pos, and if we inflate the tree the new bit being add is at +tn->pos. Previously to find those bits you would have to subtract pos and +bits from the keylength or start with a value of (1 << 31) and then shift +that. + +There are a number of spots throughout the code that benefit from this. In +the case of the hot-path searches the main advantage is that we can drop 2 +or more operations from the search path as we no longer need to compute the +value for the index to be shifted by and can instead just use the raw pos +value. + +In addition the tkey_extract_bits is now defunct and can be replaced by +get_index since the two operations were doing the same thing, but now +get_index does it much more quickly as it is only an xor and shift versus a +pair of shifts and a subtraction. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -90,8 +90,7 @@ typedef unsigned int t_key; + #define IS_TNODE(n) ((n)->bits) + #define IS_LEAF(n) (!(n)->bits) + +-#define get_shift(_kv) (KEYLENGTH - (_kv)->pos - (_kv)->bits) +-#define get_index(_key, _kv) (((_key) ^ (_kv)->key) >> get_shift(_kv)) ++#define get_index(_key, _kv) (((_key) ^ (_kv)->key) >> (_kv)->pos) + + struct tnode { + t_key key; +@@ -209,81 +208,64 @@ static inline struct tnode *tnode_get_ch + return rcu_dereference_rtnl(tn->child[i]); + } + +-static inline t_key mask_pfx(t_key k, unsigned int l) +-{ +- return (l == 0) ? 0 : k >> (KEYLENGTH-l) << (KEYLENGTH-l); +-} +- +-static inline t_key tkey_extract_bits(t_key a, unsigned int offset, unsigned int bits) +-{ +- if (offset < KEYLENGTH) +- return ((t_key)(a << offset)) >> (KEYLENGTH - bits); +- else +- return 0; +-} +- +-/* +- To understand this stuff, an understanding of keys and all their bits is +- necessary. Every node in the trie has a key associated with it, but not +- all of the bits in that key are significant. +- +- Consider a node 'n' and its parent 'tp'. +- +- If n is a leaf, every bit in its key is significant. Its presence is +- necessitated by path compression, since during a tree traversal (when +- searching for a leaf - unless we are doing an insertion) we will completely +- ignore all skipped bits we encounter. Thus we need to verify, at the end of +- a potentially successful search, that we have indeed been walking the +- correct key path. +- +- Note that we can never "miss" the correct key in the tree if present by +- following the wrong path. Path compression ensures that segments of the key +- that are the same for all keys with a given prefix are skipped, but the +- skipped part *is* identical for each node in the subtrie below the skipped +- bit! trie_insert() in this implementation takes care of that - note the +- call to tkey_sub_equals() in trie_insert(). +- +- if n is an internal node - a 'tnode' here, the various parts of its key +- have many different meanings. +- +- Example: +- _________________________________________________________________ +- | i | i | i | i | i | i | i | N | N | N | S | S | S | S | S | C | +- ----------------------------------------------------------------- +- 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 +- +- _________________________________________________________________ +- | C | C | C | u | u | u | u | u | u | u | u | u | u | u | u | u | +- ----------------------------------------------------------------- +- 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 +- +- tp->pos = 7 +- tp->bits = 3 +- n->pos = 15 +- n->bits = 4 +- +- First, let's just ignore the bits that come before the parent tp, that is +- the bits from 0 to (tp->pos-1). They are *known* but at this point we do +- not use them for anything. +- +- The bits from (tp->pos) to (tp->pos + tp->bits - 1) - "N", above - are the +- index into the parent's child array. That is, they will be used to find +- 'n' among tp's children. +- +- The bits from (tp->pos + tp->bits) to (n->pos - 1) - "S" - are skipped bits +- for the node n. +- +- All the bits we have seen so far are significant to the node n. The rest +- of the bits are really not needed or indeed known in n->key. +- +- The bits from (n->pos) to (n->pos + n->bits - 1) - "C" - are the index into +- n's child array, and will of course be different for each child. +- +- +- The rest of the bits, from (n->pos + n->bits) onward, are completely unknown +- at this point. +- +-*/ ++/* To understand this stuff, an understanding of keys and all their bits is ++ * necessary. Every node in the trie has a key associated with it, but not ++ * all of the bits in that key are significant. ++ * ++ * Consider a node 'n' and its parent 'tp'. ++ * ++ * If n is a leaf, every bit in its key is significant. Its presence is ++ * necessitated by path compression, since during a tree traversal (when ++ * searching for a leaf - unless we are doing an insertion) we will completely ++ * ignore all skipped bits we encounter. Thus we need to verify, at the end of ++ * a potentially successful search, that we have indeed been walking the ++ * correct key path. ++ * ++ * Note that we can never "miss" the correct key in the tree if present by ++ * following the wrong path. Path compression ensures that segments of the key ++ * that are the same for all keys with a given prefix are skipped, but the ++ * skipped part *is* identical for each node in the subtrie below the skipped ++ * bit! trie_insert() in this implementation takes care of that. ++ * ++ * if n is an internal node - a 'tnode' here, the various parts of its key ++ * have many different meanings. ++ * ++ * Example: ++ * _________________________________________________________________ ++ * | i | i | i | i | i | i | i | N | N | N | S | S | S | S | S | C | ++ * ----------------------------------------------------------------- ++ * 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 ++ * ++ * _________________________________________________________________ ++ * | C | C | C | u | u | u | u | u | u | u | u | u | u | u | u | u | ++ * ----------------------------------------------------------------- ++ * 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ++ * ++ * tp->pos = 22 ++ * tp->bits = 3 ++ * n->pos = 13 ++ * n->bits = 4 ++ * ++ * First, let's just ignore the bits that come before the parent tp, that is ++ * the bits from (tp->pos + tp->bits) to 31. They are *known* but at this ++ * point we do not use them for anything. ++ * ++ * The bits from (tp->pos) to (tp->pos + tp->bits - 1) - "N", above - are the ++ * index into the parent's child array. That is, they will be used to find ++ * 'n' among tp's children. ++ * ++ * The bits from (n->pos + n->bits) to (tn->pos - 1) - "S" - are skipped bits ++ * for the node n. ++ * ++ * All the bits we have seen so far are significant to the node n. The rest ++ * of the bits are really not needed or indeed known in n->key. ++ * ++ * The bits from (n->pos) to (n->pos + n->bits - 1) - "C" - are the index into ++ * n's child array, and will of course be different for each child. ++ * ++ * The rest of the bits, from 0 to (n->pos + n->bits), are completely unknown ++ * at this point. ++ */ + + static const int halve_threshold = 25; + static const int inflate_threshold = 50; +@@ -367,7 +349,7 @@ static struct tnode *leaf_new(t_key key) + * as the nodes are searched + */ + l->key = key; +- l->pos = KEYLENGTH; ++ l->pos = 0; + /* set bits to 0 indicating we are not a tnode */ + l->bits = 0; + +@@ -400,7 +382,7 @@ static struct tnode *tnode_new(t_key key + tn->parent = NULL; + tn->pos = pos; + tn->bits = bits; +- tn->key = mask_pfx(key, pos); ++ tn->key = (shift < KEYLENGTH) ? (key >> shift) << shift : 0; + tn->full_children = 0; + tn->empty_children = 1<<bits; + } +@@ -410,14 +392,12 @@ static struct tnode *tnode_new(t_key key + return tn; + } + +-/* +- * Check whether a tnode 'n' is "full", i.e. it is an internal node ++/* Check whether a tnode 'n' is "full", i.e. it is an internal node + * and no bits are skipped. See discussion in dyntree paper p. 6 + */ +- + static inline int tnode_full(const struct tnode *tn, const struct tnode *n) + { +- return n && IS_TNODE(n) && (n->pos == (tn->pos + tn->bits)); ++ return n && ((n->pos + n->bits) == tn->pos) && IS_TNODE(n); + } + + static inline void put_child(struct tnode *tn, int i, +@@ -641,11 +621,12 @@ static struct tnode *inflate(struct trie + { + int olen = tnode_child_length(oldtnode); + struct tnode *tn; ++ t_key m; + int i; + + pr_debug("In inflate\n"); + +- tn = tnode_new(oldtnode->key, oldtnode->pos, oldtnode->bits + 1); ++ tn = tnode_new(oldtnode->key, oldtnode->pos - 1, oldtnode->bits + 1); + + if (!tn) + return ERR_PTR(-ENOMEM); +@@ -656,21 +637,18 @@ static struct tnode *inflate(struct trie + * fails. In case of failure we return the oldnode and inflate + * of tnode is ignored. + */ ++ for (i = 0, m = 1u << tn->pos; i < olen; i++) { ++ struct tnode *inode = tnode_get_child(oldtnode, i); + +- for (i = 0; i < olen; i++) { +- struct tnode *inode; +- +- inode = tnode_get_child(oldtnode, i); +- if (tnode_full(oldtnode, inode) && inode->bits > 1) { ++ if (tnode_full(oldtnode, inode) && (inode->bits > 1)) { + struct tnode *left, *right; +- t_key m = ~0U << (KEYLENGTH - 1) >> inode->pos; + +- left = tnode_new(inode->key&(~m), inode->pos + 1, ++ left = tnode_new(inode->key & ~m, inode->pos, + inode->bits - 1); + if (!left) + goto nomem; + +- right = tnode_new(inode->key|m, inode->pos + 1, ++ right = tnode_new(inode->key | m, inode->pos, + inode->bits - 1); + + if (!right) { +@@ -694,9 +672,7 @@ static struct tnode *inflate(struct trie + + /* A leaf or an internal node with skipped bits */ + if (!tnode_full(oldtnode, inode)) { +- put_child(tn, +- tkey_extract_bits(inode->key, tn->pos, tn->bits), +- inode); ++ put_child(tn, get_index(inode->key, tn), inode); + continue; + } + +@@ -767,7 +743,7 @@ static struct tnode *halve(struct trie * + + pr_debug("In halve\n"); + +- tn = tnode_new(oldtnode->key, oldtnode->pos, oldtnode->bits - 1); ++ tn = tnode_new(oldtnode->key, oldtnode->pos + 1, oldtnode->bits - 1); + + if (!tn) + return ERR_PTR(-ENOMEM); +@@ -787,7 +763,7 @@ static struct tnode *halve(struct trie * + if (left && right) { + struct tnode *newn; + +- newn = tnode_new(left->key, tn->pos + tn->bits, 1); ++ newn = tnode_new(left->key, oldtnode->pos, 1); + + if (!newn) + goto nomem; +@@ -915,7 +891,7 @@ static void trie_rebalance(struct trie * + key = tn->key; + + while (tn != NULL && (tp = node_parent(tn)) != NULL) { +- cindex = tkey_extract_bits(key, tp->pos, tp->bits); ++ cindex = get_index(key, tp); + wasfull = tnode_full(tp, tnode_get_child(tp, cindex)); + tn = resize(t, tn); + +@@ -1005,11 +981,8 @@ static struct list_head *fib_insert_node + */ + if (n) { + struct tnode *tn; +- int newpos; +- +- newpos = KEYLENGTH - __fls(n->key ^ key) - 1; + +- tn = tnode_new(key, newpos, 1); ++ tn = tnode_new(key, __fls(key ^ n->key), 1); + if (!tn) { + free_leaf_info(li); + node_free(l); +@@ -1559,12 +1532,7 @@ static int trie_flush_leaf(struct tnode + static struct tnode *leaf_walk_rcu(struct tnode *p, struct tnode *c) + { + do { +- t_key idx; +- +- if (c) +- idx = tkey_extract_bits(c->key, p->pos, p->bits) + 1; +- else +- idx = 0; ++ t_key idx = c ? idx = get_index(c->key, p) + 1 : 0; + + while (idx < 1u << p->bits) { + c = tnode_get_child_rcu(p, idx++); +@@ -1851,7 +1819,7 @@ rescan: + /* Current node exhausted, pop back up */ + p = node_parent_rcu(tn); + if (p) { +- cindex = tkey_extract_bits(tn->key, p->pos, p->bits)+1; ++ cindex = get_index(tn->key, p) + 1; + tn = p; + --iter->depth; + goto rescan; +@@ -2187,10 +2155,10 @@ static int fib_trie_seq_show(struct seq_ + if (IS_TNODE(n)) { + __be32 prf = htonl(n->key); + +- seq_indent(seq, iter->depth - 1); +- seq_printf(seq, " +-- %pI4/%d %d %d %d\n", +- &prf, n->pos, n->bits, n->full_children, +- n->empty_children); ++ seq_indent(seq, iter->depth-1); ++ seq_printf(seq, " +-- %pI4/%zu %u %u %u\n", ++ &prf, KEYLENGTH - n->pos - n->bits, n->bits, ++ n->full_children, n->empty_children); + } else { + struct leaf_info *li; + __be32 val = htonl(n->key); diff --git a/target/linux/generic/patches-3.18/080-10-fib_trie-Use-unsigned-long-for-anything-dealing-with.patch b/target/linux/generic/patches-3.18/080-10-fib_trie-Use-unsigned-long-for-anything-dealing-with.patch new file mode 100644 index 0000000000..7acf8b67a2 --- /dev/null +++ b/target/linux/generic/patches-3.18/080-10-fib_trie-Use-unsigned-long-for-anything-dealing-with.patch @@ -0,0 +1,186 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Wed, 31 Dec 2014 10:56:18 -0800 +Subject: [PATCH] fib_trie: Use unsigned long for anything dealing with a + shift by bits + +This change makes it so that anything that can be shifted by, or compared +to a value shifted by bits is updated to be an unsigned long. This is +mostly a precaution against an insanely huge address space that somehow +starts coming close to the 2^32 root node size which would require +something like 1.5 billion addresses. + +I chose unsigned long instead of unsigned long long since I do not believe +it is possible to allocate a 32 bit tnode on a 32 bit system as the memory +consumed would be 16GB + 28B which exceeds the addressible space for any +one process. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -146,8 +146,8 @@ struct trie { + #endif + }; + +-static void tnode_put_child_reorg(struct tnode *tn, int i, struct tnode *n, +- int wasfull); ++static void tnode_put_child_reorg(struct tnode *tn, unsigned long i, ++ struct tnode *n, int wasfull); + static struct tnode *resize(struct trie *t, struct tnode *tn); + static struct tnode *inflate(struct trie *t, struct tnode *tn); + static struct tnode *halve(struct trie *t, struct tnode *tn); +@@ -183,25 +183,23 @@ static inline void node_set_parent(struc + /* This provides us with the number of children in this node, in the case of a + * leaf this will return 0 meaning none of the children are accessible. + */ +-static inline int tnode_child_length(const struct tnode *tn) ++static inline unsigned long tnode_child_length(const struct tnode *tn) + { + return (1ul << tn->bits) & ~(1ul); + } + +-/* +- * caller must hold RTNL +- */ +-static inline struct tnode *tnode_get_child(const struct tnode *tn, unsigned int i) ++/* caller must hold RTNL */ ++static inline struct tnode *tnode_get_child(const struct tnode *tn, ++ unsigned long i) + { + BUG_ON(i >= tnode_child_length(tn)); + + return rtnl_dereference(tn->child[i]); + } + +-/* +- * caller must hold RCU read lock or RTNL +- */ +-static inline struct tnode *tnode_get_child_rcu(const struct tnode *tn, unsigned int i) ++/* caller must hold RCU read lock or RTNL */ ++static inline struct tnode *tnode_get_child_rcu(const struct tnode *tn, ++ unsigned long i) + { + BUG_ON(i >= tnode_child_length(tn)); + +@@ -400,7 +398,7 @@ static inline int tnode_full(const struc + return n && ((n->pos + n->bits) == tn->pos) && IS_TNODE(n); + } + +-static inline void put_child(struct tnode *tn, int i, ++static inline void put_child(struct tnode *tn, unsigned long i, + struct tnode *n) + { + tnode_put_child_reorg(tn, i, n, -1); +@@ -411,13 +409,13 @@ static inline void put_child(struct tnod + * Update the value of full_children and empty_children. + */ + +-static void tnode_put_child_reorg(struct tnode *tn, int i, struct tnode *n, +- int wasfull) ++static void tnode_put_child_reorg(struct tnode *tn, unsigned long i, ++ struct tnode *n, int wasfull) + { + struct tnode *chi = rtnl_dereference(tn->child[i]); + int isfull; + +- BUG_ON(i >= 1<<tn->bits); ++ BUG_ON(i >= tnode_child_length(tn)); + + /* update emptyChildren */ + if (n == NULL && chi != NULL) +@@ -607,10 +605,10 @@ no_children: + static void tnode_clean_free(struct tnode *tn) + { + struct tnode *tofree; +- int i; ++ unsigned long i; + + for (i = 0; i < tnode_child_length(tn); i++) { +- tofree = rtnl_dereference(tn->child[i]); ++ tofree = tnode_get_child(tn, i); + if (tofree) + node_free(tofree); + } +@@ -619,10 +617,10 @@ static void tnode_clean_free(struct tnod + + static struct tnode *inflate(struct trie *t, struct tnode *oldtnode) + { +- int olen = tnode_child_length(oldtnode); ++ unsigned long olen = tnode_child_length(oldtnode); + struct tnode *tn; ++ unsigned long i; + t_key m; +- int i; + + pr_debug("In inflate\n"); + +@@ -664,7 +662,7 @@ static struct tnode *inflate(struct trie + for (i = 0; i < olen; i++) { + struct tnode *inode = tnode_get_child(oldtnode, i); + struct tnode *left, *right; +- int size, j; ++ unsigned long size, j; + + /* An empty child */ + if (inode == NULL) +@@ -737,7 +735,7 @@ nomem: + + static struct tnode *halve(struct trie *t, struct tnode *oldtnode) + { +- int olen = tnode_child_length(oldtnode); ++ unsigned long olen = tnode_child_length(oldtnode); + struct tnode *tn, *left, *right; + int i; + +@@ -1532,9 +1530,9 @@ static int trie_flush_leaf(struct tnode + static struct tnode *leaf_walk_rcu(struct tnode *p, struct tnode *c) + { + do { +- t_key idx = c ? idx = get_index(c->key, p) + 1 : 0; ++ unsigned long idx = c ? idx = get_index(c->key, p) + 1 : 0; + +- while (idx < 1u << p->bits) { ++ while (idx < tnode_child_length(p)) { + c = tnode_get_child_rcu(p, idx++); + if (!c) + continue; +@@ -1786,8 +1784,8 @@ struct fib_trie_iter { + + static struct tnode *fib_trie_get_next(struct fib_trie_iter *iter) + { ++ unsigned long cindex = iter->index; + struct tnode *tn = iter->tnode; +- unsigned int cindex = iter->index; + struct tnode *p; + + /* A single entry routing table */ +@@ -1797,7 +1795,7 @@ static struct tnode *fib_trie_get_next(s + pr_debug("get_next iter={node=%p index=%d depth=%d}\n", + iter->tnode, iter->index, iter->depth); + rescan: +- while (cindex < (1<<tn->bits)) { ++ while (cindex < tnode_child_length(tn)) { + struct tnode *n = tnode_get_child_rcu(tn, cindex); + + if (n) { +@@ -1874,15 +1872,16 @@ static void trie_collect_stats(struct tr + hlist_for_each_entry_rcu(li, &n->list, hlist) + ++s->prefixes; + } else { +- int i; ++ unsigned long i; + + s->tnodes++; + if (n->bits < MAX_STAT_DEPTH) + s->nodesizes[n->bits]++; + +- for (i = 0; i < tnode_child_length(n); i++) ++ for (i = 0; i < tnode_child_length(n); i++) { + if (!rcu_access_pointer(n->child[i])) + s->nullpointers++; ++ } + } + } + rcu_read_unlock(); diff --git a/target/linux/generic/patches-3.18/080-11-fib_trie-Push-rcu_read_lock-unlock-to-callers.patch b/target/linux/generic/patches-3.18/080-11-fib_trie-Push-rcu_read_lock-unlock-to-callers.patch new file mode 100644 index 0000000000..5c2dcf3472 --- /dev/null +++ b/target/linux/generic/patches-3.18/080-11-fib_trie-Push-rcu_read_lock-unlock-to-callers.patch @@ -0,0 +1,403 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Wed, 31 Dec 2014 10:56:24 -0800 +Subject: [PATCH] fib_trie: Push rcu_read_lock/unlock to callers + +This change is to start cleaning up some of the rcu_read_lock/unlock +handling. I realized while reviewing the code there are several spots that +I don't believe are being handled correctly or are masking warnings by +locally calling rcu_read_lock/unlock instead of calling them at the correct +level. + +A common example is a call to fib_get_table followed by fib_table_lookup. +The rcu_read_lock/unlock ought to wrap both but there are several spots where +they were not wrapped. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/include/net/ip_fib.h ++++ b/include/net/ip_fib.h +@@ -222,16 +222,19 @@ static inline struct fib_table *fib_new_ + static inline int fib_lookup(struct net *net, const struct flowi4 *flp, + struct fib_result *res) + { +- struct fib_table *table; ++ int err = -ENETUNREACH; + +- table = fib_get_table(net, RT_TABLE_LOCAL); +- if (!fib_table_lookup(table, flp, res, FIB_LOOKUP_NOREF)) +- return 0; +- +- table = fib_get_table(net, RT_TABLE_MAIN); +- if (!fib_table_lookup(table, flp, res, FIB_LOOKUP_NOREF)) +- return 0; +- return -ENETUNREACH; ++ rcu_read_lock(); ++ ++ if (!fib_table_lookup(fib_get_table(net, RT_TABLE_LOCAL), flp, res, ++ FIB_LOOKUP_NOREF) || ++ !fib_table_lookup(fib_get_table(net, RT_TABLE_MAIN), flp, res, ++ FIB_LOOKUP_NOREF)) ++ err = 0; ++ ++ rcu_read_unlock(); ++ ++ return err; + } + + #else /* CONFIG_IP_MULTIPLE_TABLES */ +@@ -247,20 +250,25 @@ static inline int fib_lookup(struct net + struct fib_result *res) + { + if (!net->ipv4.fib_has_custom_rules) { ++ int err = -ENETUNREACH; ++ ++ rcu_read_lock(); ++ + res->tclassid = 0; +- if (net->ipv4.fib_local && +- !fib_table_lookup(net->ipv4.fib_local, flp, res, +- FIB_LOOKUP_NOREF)) +- return 0; +- if (net->ipv4.fib_main && +- !fib_table_lookup(net->ipv4.fib_main, flp, res, +- FIB_LOOKUP_NOREF)) +- return 0; +- if (net->ipv4.fib_default && +- !fib_table_lookup(net->ipv4.fib_default, flp, res, +- FIB_LOOKUP_NOREF)) +- return 0; +- return -ENETUNREACH; ++ if ((net->ipv4.fib_local && ++ !fib_table_lookup(net->ipv4.fib_local, flp, res, ++ FIB_LOOKUP_NOREF)) || ++ (net->ipv4.fib_main && ++ !fib_table_lookup(net->ipv4.fib_main, flp, res, ++ FIB_LOOKUP_NOREF)) || ++ (net->ipv4.fib_default && ++ !fib_table_lookup(net->ipv4.fib_default, flp, res, ++ FIB_LOOKUP_NOREF))) ++ err = 0; ++ ++ rcu_read_unlock(); ++ ++ return err; + } + return __fib_lookup(net, flp, res); + } +--- a/net/ipv4/fib_frontend.c ++++ b/net/ipv4/fib_frontend.c +@@ -109,6 +109,7 @@ struct fib_table *fib_new_table(struct n + return tb; + } + ++/* caller must hold either rtnl or rcu read lock */ + struct fib_table *fib_get_table(struct net *net, u32 id) + { + struct fib_table *tb; +@@ -119,15 +120,11 @@ struct fib_table *fib_get_table(struct n + id = RT_TABLE_MAIN; + h = id & (FIB_TABLE_HASHSZ - 1); + +- rcu_read_lock(); + head = &net->ipv4.fib_table_hash[h]; + hlist_for_each_entry_rcu(tb, head, tb_hlist) { +- if (tb->tb_id == id) { +- rcu_read_unlock(); ++ if (tb->tb_id == id) + return tb; +- } + } +- rcu_read_unlock(); + return NULL; + } + #endif /* CONFIG_IP_MULTIPLE_TABLES */ +@@ -167,16 +164,18 @@ static inline unsigned int __inet_dev_ad + if (ipv4_is_multicast(addr)) + return RTN_MULTICAST; + ++ rcu_read_lock(); ++ + local_table = fib_get_table(net, RT_TABLE_LOCAL); + if (local_table) { + ret = RTN_UNICAST; +- rcu_read_lock(); + if (!fib_table_lookup(local_table, &fl4, &res, FIB_LOOKUP_NOREF)) { + if (!dev || dev == res.fi->fib_dev) + ret = res.type; + } +- rcu_read_unlock(); + } ++ ++ rcu_read_unlock(); + return ret; + } + +@@ -919,7 +918,7 @@ void fib_del_ifaddr(struct in_ifaddr *if + #undef BRD1_OK + } + +-static void nl_fib_lookup(struct fib_result_nl *frn, struct fib_table *tb) ++static void nl_fib_lookup(struct net *net, struct fib_result_nl *frn) + { + + struct fib_result res; +@@ -929,6 +928,11 @@ static void nl_fib_lookup(struct fib_res + .flowi4_tos = frn->fl_tos, + .flowi4_scope = frn->fl_scope, + }; ++ struct fib_table *tb; ++ ++ rcu_read_lock(); ++ ++ tb = fib_get_table(net, frn->tb_id_in); + + frn->err = -ENOENT; + if (tb) { +@@ -945,6 +949,8 @@ static void nl_fib_lookup(struct fib_res + } + local_bh_enable(); + } ++ ++ rcu_read_unlock(); + } + + static void nl_fib_input(struct sk_buff *skb) +@@ -952,7 +958,6 @@ static void nl_fib_input(struct sk_buff + struct net *net; + struct fib_result_nl *frn; + struct nlmsghdr *nlh; +- struct fib_table *tb; + u32 portid; + + net = sock_net(skb->sk); +@@ -967,9 +972,7 @@ static void nl_fib_input(struct sk_buff + nlh = nlmsg_hdr(skb); + + frn = (struct fib_result_nl *) nlmsg_data(nlh); +- tb = fib_get_table(net, frn->tb_id_in); +- +- nl_fib_lookup(frn, tb); ++ nl_fib_lookup(net, frn); + + portid = NETLINK_CB(skb).portid; /* netlink portid */ + NETLINK_CB(skb).portid = 0; /* from kernel */ +--- a/net/ipv4/fib_rules.c ++++ b/net/ipv4/fib_rules.c +@@ -81,27 +81,25 @@ static int fib4_rule_action(struct fib_r + break; + + case FR_ACT_UNREACHABLE: +- err = -ENETUNREACH; +- goto errout; ++ return -ENETUNREACH; + + case FR_ACT_PROHIBIT: +- err = -EACCES; +- goto errout; ++ return -EACCES; + + case FR_ACT_BLACKHOLE: + default: +- err = -EINVAL; +- goto errout; ++ return -EINVAL; + } + ++ rcu_read_lock(); ++ + tbl = fib_get_table(rule->fr_net, rule->table); +- if (!tbl) +- goto errout; ++ if (tbl) ++ err = fib_table_lookup(tbl, &flp->u.ip4, ++ (struct fib_result *)arg->result, ++ arg->flags); + +- err = fib_table_lookup(tbl, &flp->u.ip4, (struct fib_result *) arg->result, arg->flags); +- if (err > 0) +- err = -EAGAIN; +-errout: ++ rcu_read_unlock(); + return err; + } + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -1181,72 +1181,6 @@ err: + return err; + } + +-/* should be called with rcu_read_lock */ +-static int check_leaf(struct fib_table *tb, struct trie *t, struct tnode *l, +- t_key key, const struct flowi4 *flp, +- struct fib_result *res, int fib_flags) +-{ +- struct leaf_info *li; +- struct hlist_head *hhead = &l->list; +- +- hlist_for_each_entry_rcu(li, hhead, hlist) { +- struct fib_alias *fa; +- +- if (l->key != (key & li->mask_plen)) +- continue; +- +- list_for_each_entry_rcu(fa, &li->falh, fa_list) { +- struct fib_info *fi = fa->fa_info; +- int nhsel, err; +- +- if (fa->fa_tos && fa->fa_tos != flp->flowi4_tos) +- continue; +- if (fi->fib_dead) +- continue; +- if (fa->fa_info->fib_scope < flp->flowi4_scope) +- continue; +- fib_alias_accessed(fa); +- err = fib_props[fa->fa_type].error; +- if (unlikely(err < 0)) { +-#ifdef CONFIG_IP_FIB_TRIE_STATS +- this_cpu_inc(t->stats->semantic_match_passed); +-#endif +- return err; +- } +- if (fi->fib_flags & RTNH_F_DEAD) +- continue; +- for (nhsel = 0; nhsel < fi->fib_nhs; nhsel++) { +- const struct fib_nh *nh = &fi->fib_nh[nhsel]; +- +- if (nh->nh_flags & RTNH_F_DEAD) +- continue; +- if (flp->flowi4_oif && flp->flowi4_oif != nh->nh_oif) +- continue; +- +-#ifdef CONFIG_IP_FIB_TRIE_STATS +- this_cpu_inc(t->stats->semantic_match_passed); +-#endif +- res->prefixlen = li->plen; +- res->nh_sel = nhsel; +- res->type = fa->fa_type; +- res->scope = fi->fib_scope; +- res->fi = fi; +- res->table = tb; +- res->fa_head = &li->falh; +- if (!(fib_flags & FIB_LOOKUP_NOREF)) +- atomic_inc(&fi->fib_clntref); +- return 0; +- } +- } +- +-#ifdef CONFIG_IP_FIB_TRIE_STATS +- this_cpu_inc(t->stats->semantic_match_miss); +-#endif +- } +- +- return 1; +-} +- + static inline t_key prefix_mismatch(t_key key, struct tnode *n) + { + t_key prefix = n->key; +@@ -1254,6 +1188,7 @@ static inline t_key prefix_mismatch(t_ke + return (key ^ prefix) & (prefix | -prefix); + } + ++/* should be called with rcu_read_lock */ + int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp, + struct fib_result *res, int fib_flags) + { +@@ -1263,14 +1198,12 @@ int fib_table_lookup(struct fib_table *t + #endif + const t_key key = ntohl(flp->daddr); + struct tnode *n, *pn; ++ struct leaf_info *li; + t_key cindex; +- int ret = 1; +- +- rcu_read_lock(); + + n = rcu_dereference(t->trie); + if (!n) +- goto failed; ++ return -EAGAIN; + + #ifdef CONFIG_IP_FIB_TRIE_STATS + this_cpu_inc(stats->gets); +@@ -1350,7 +1283,7 @@ backtrace: + + pn = node_parent_rcu(pn); + if (unlikely(!pn)) +- goto failed; ++ return -EAGAIN; + #ifdef CONFIG_IP_FIB_TRIE_STATS + this_cpu_inc(stats->backtrack); + #endif +@@ -1368,12 +1301,62 @@ backtrace: + + found: + /* Step 3: Process the leaf, if that fails fall back to backtracing */ +- ret = check_leaf(tb, t, n, key, flp, res, fib_flags); +- if (unlikely(ret > 0)) +- goto backtrace; +-failed: +- rcu_read_unlock(); +- return ret; ++ hlist_for_each_entry_rcu(li, &n->list, hlist) { ++ struct fib_alias *fa; ++ ++ if ((key ^ n->key) & li->mask_plen) ++ continue; ++ ++ list_for_each_entry_rcu(fa, &li->falh, fa_list) { ++ struct fib_info *fi = fa->fa_info; ++ int nhsel, err; ++ ++ if (fa->fa_tos && fa->fa_tos != flp->flowi4_tos) ++ continue; ++ if (fi->fib_dead) ++ continue; ++ if (fa->fa_info->fib_scope < flp->flowi4_scope) ++ continue; ++ fib_alias_accessed(fa); ++ err = fib_props[fa->fa_type].error; ++ if (unlikely(err < 0)) { ++#ifdef CONFIG_IP_FIB_TRIE_STATS ++ this_cpu_inc(stats->semantic_match_passed); ++#endif ++ return err; ++ } ++ if (fi->fib_flags & RTNH_F_DEAD) ++ continue; ++ for (nhsel = 0; nhsel < fi->fib_nhs; nhsel++) { ++ const struct fib_nh *nh = &fi->fib_nh[nhsel]; ++ ++ if (nh->nh_flags & RTNH_F_DEAD) ++ continue; ++ if (flp->flowi4_oif && flp->flowi4_oif != nh->nh_oif) ++ continue; ++ ++ if (!(fib_flags & FIB_LOOKUP_NOREF)) ++ atomic_inc(&fi->fib_clntref); ++ ++ res->prefixlen = li->plen; ++ res->nh_sel = nhsel; ++ res->type = fa->fa_type; ++ res->scope = fi->fib_scope; ++ res->fi = fi; ++ res->table = tb; ++ res->fa_head = &li->falh; ++#ifdef CONFIG_IP_FIB_TRIE_STATS ++ this_cpu_inc(stats->semantic_match_passed); ++#endif ++ return err; ++ } ++ } ++ ++#ifdef CONFIG_IP_FIB_TRIE_STATS ++ this_cpu_inc(stats->semantic_match_miss); ++#endif ++ } ++ goto backtrace; + } + EXPORT_SYMBOL_GPL(fib_table_lookup); + diff --git a/target/linux/generic/patches-3.18/080-12-fib_trie-Move-resize-to-after-inflate-halve.patch b/target/linux/generic/patches-3.18/080-12-fib_trie-Move-resize-to-after-inflate-halve.patch new file mode 100644 index 0000000000..6edcfdcfec --- /dev/null +++ b/target/linux/generic/patches-3.18/080-12-fib_trie-Move-resize-to-after-inflate-halve.patch @@ -0,0 +1,345 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Wed, 31 Dec 2014 10:56:31 -0800 +Subject: [PATCH] fib_trie: Move resize to after inflate/halve + +This change consists of a cut/paste of resize to behind inflate and halve +so that I could remove the two function prototypes. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -149,8 +149,6 @@ struct trie { + static void tnode_put_child_reorg(struct tnode *tn, unsigned long i, + struct tnode *n, int wasfull); + static struct tnode *resize(struct trie *t, struct tnode *tn); +-static struct tnode *inflate(struct trie *t, struct tnode *tn); +-static struct tnode *halve(struct trie *t, struct tnode *tn); + /* tnodes to free after resize(); protected by RTNL */ + static struct callback_head *tnode_free_head; + static size_t tnode_free_size; +@@ -447,161 +445,6 @@ static void put_child_root(struct tnode + rcu_assign_pointer(t->trie, n); + } + +-#define MAX_WORK 10 +-static struct tnode *resize(struct trie *t, struct tnode *tn) +-{ +- struct tnode *old_tn, *n = NULL; +- int inflate_threshold_use; +- int halve_threshold_use; +- int max_work; +- +- if (!tn) +- return NULL; +- +- pr_debug("In tnode_resize %p inflate_threshold=%d threshold=%d\n", +- tn, inflate_threshold, halve_threshold); +- +- /* No children */ +- if (tn->empty_children > (tnode_child_length(tn) - 1)) +- goto no_children; +- +- /* One child */ +- if (tn->empty_children == (tnode_child_length(tn) - 1)) +- goto one_child; +- /* +- * Double as long as the resulting node has a number of +- * nonempty nodes that are above the threshold. +- */ +- +- /* +- * From "Implementing a dynamic compressed trie" by Stefan Nilsson of +- * the Helsinki University of Technology and Matti Tikkanen of Nokia +- * Telecommunications, page 6: +- * "A node is doubled if the ratio of non-empty children to all +- * children in the *doubled* node is at least 'high'." +- * +- * 'high' in this instance is the variable 'inflate_threshold'. It +- * is expressed as a percentage, so we multiply it with +- * tnode_child_length() and instead of multiplying by 2 (since the +- * child array will be doubled by inflate()) and multiplying +- * the left-hand side by 100 (to handle the percentage thing) we +- * multiply the left-hand side by 50. +- * +- * The left-hand side may look a bit weird: tnode_child_length(tn) +- * - tn->empty_children is of course the number of non-null children +- * in the current node. tn->full_children is the number of "full" +- * children, that is non-null tnodes with a skip value of 0. +- * All of those will be doubled in the resulting inflated tnode, so +- * we just count them one extra time here. +- * +- * A clearer way to write this would be: +- * +- * to_be_doubled = tn->full_children; +- * not_to_be_doubled = tnode_child_length(tn) - tn->empty_children - +- * tn->full_children; +- * +- * new_child_length = tnode_child_length(tn) * 2; +- * +- * new_fill_factor = 100 * (not_to_be_doubled + 2*to_be_doubled) / +- * new_child_length; +- * if (new_fill_factor >= inflate_threshold) +- * +- * ...and so on, tho it would mess up the while () loop. +- * +- * anyway, +- * 100 * (not_to_be_doubled + 2*to_be_doubled) / new_child_length >= +- * inflate_threshold +- * +- * avoid a division: +- * 100 * (not_to_be_doubled + 2*to_be_doubled) >= +- * inflate_threshold * new_child_length +- * +- * expand not_to_be_doubled and to_be_doubled, and shorten: +- * 100 * (tnode_child_length(tn) - tn->empty_children + +- * tn->full_children) >= inflate_threshold * new_child_length +- * +- * expand new_child_length: +- * 100 * (tnode_child_length(tn) - tn->empty_children + +- * tn->full_children) >= +- * inflate_threshold * tnode_child_length(tn) * 2 +- * +- * shorten again: +- * 50 * (tn->full_children + tnode_child_length(tn) - +- * tn->empty_children) >= inflate_threshold * +- * tnode_child_length(tn) +- * +- */ +- +- /* Keep root node larger */ +- +- if (!node_parent(tn)) { +- inflate_threshold_use = inflate_threshold_root; +- halve_threshold_use = halve_threshold_root; +- } else { +- inflate_threshold_use = inflate_threshold; +- halve_threshold_use = halve_threshold; +- } +- +- max_work = MAX_WORK; +- while ((tn->full_children > 0 && max_work-- && +- 50 * (tn->full_children + tnode_child_length(tn) +- - tn->empty_children) +- >= inflate_threshold_use * tnode_child_length(tn))) { +- +- old_tn = tn; +- tn = inflate(t, tn); +- +- if (IS_ERR(tn)) { +- tn = old_tn; +-#ifdef CONFIG_IP_FIB_TRIE_STATS +- this_cpu_inc(t->stats->resize_node_skipped); +-#endif +- break; +- } +- } +- +- /* Return if at least one inflate is run */ +- if (max_work != MAX_WORK) +- return tn; +- +- /* +- * Halve as long as the number of empty children in this +- * node is above threshold. +- */ +- +- max_work = MAX_WORK; +- while (tn->bits > 1 && max_work-- && +- 100 * (tnode_child_length(tn) - tn->empty_children) < +- halve_threshold_use * tnode_child_length(tn)) { +- +- old_tn = tn; +- tn = halve(t, tn); +- if (IS_ERR(tn)) { +- tn = old_tn; +-#ifdef CONFIG_IP_FIB_TRIE_STATS +- this_cpu_inc(t->stats->resize_node_skipped); +-#endif +- break; +- } +- } +- +- +- /* Only one child remains */ +- if (tn->empty_children == (tnode_child_length(tn) - 1)) { +- unsigned long i; +-one_child: +- for (i = tnode_child_length(tn); !n && i;) +- n = tnode_get_child(tn, --i); +-no_children: +- /* compress one level */ +- node_set_parent(n, NULL); +- tnode_free_safe(tn); +- return n; +- } +- return tn; +-} +- +- + static void tnode_clean_free(struct tnode *tn) + { + struct tnode *tofree; +@@ -804,6 +647,160 @@ nomem: + return ERR_PTR(-ENOMEM); + } + ++#define MAX_WORK 10 ++static struct tnode *resize(struct trie *t, struct tnode *tn) ++{ ++ struct tnode *old_tn, *n = NULL; ++ int inflate_threshold_use; ++ int halve_threshold_use; ++ int max_work; ++ ++ if (!tn) ++ return NULL; ++ ++ pr_debug("In tnode_resize %p inflate_threshold=%d threshold=%d\n", ++ tn, inflate_threshold, halve_threshold); ++ ++ /* No children */ ++ if (tn->empty_children > (tnode_child_length(tn) - 1)) ++ goto no_children; ++ ++ /* One child */ ++ if (tn->empty_children == (tnode_child_length(tn) - 1)) ++ goto one_child; ++ /* ++ * Double as long as the resulting node has a number of ++ * nonempty nodes that are above the threshold. ++ */ ++ ++ /* ++ * From "Implementing a dynamic compressed trie" by Stefan Nilsson of ++ * the Helsinki University of Technology and Matti Tikkanen of Nokia ++ * Telecommunications, page 6: ++ * "A node is doubled if the ratio of non-empty children to all ++ * children in the *doubled* node is at least 'high'." ++ * ++ * 'high' in this instance is the variable 'inflate_threshold'. It ++ * is expressed as a percentage, so we multiply it with ++ * tnode_child_length() and instead of multiplying by 2 (since the ++ * child array will be doubled by inflate()) and multiplying ++ * the left-hand side by 100 (to handle the percentage thing) we ++ * multiply the left-hand side by 50. ++ * ++ * The left-hand side may look a bit weird: tnode_child_length(tn) ++ * - tn->empty_children is of course the number of non-null children ++ * in the current node. tn->full_children is the number of "full" ++ * children, that is non-null tnodes with a skip value of 0. ++ * All of those will be doubled in the resulting inflated tnode, so ++ * we just count them one extra time here. ++ * ++ * A clearer way to write this would be: ++ * ++ * to_be_doubled = tn->full_children; ++ * not_to_be_doubled = tnode_child_length(tn) - tn->empty_children - ++ * tn->full_children; ++ * ++ * new_child_length = tnode_child_length(tn) * 2; ++ * ++ * new_fill_factor = 100 * (not_to_be_doubled + 2*to_be_doubled) / ++ * new_child_length; ++ * if (new_fill_factor >= inflate_threshold) ++ * ++ * ...and so on, tho it would mess up the while () loop. ++ * ++ * anyway, ++ * 100 * (not_to_be_doubled + 2*to_be_doubled) / new_child_length >= ++ * inflate_threshold ++ * ++ * avoid a division: ++ * 100 * (not_to_be_doubled + 2*to_be_doubled) >= ++ * inflate_threshold * new_child_length ++ * ++ * expand not_to_be_doubled and to_be_doubled, and shorten: ++ * 100 * (tnode_child_length(tn) - tn->empty_children + ++ * tn->full_children) >= inflate_threshold * new_child_length ++ * ++ * expand new_child_length: ++ * 100 * (tnode_child_length(tn) - tn->empty_children + ++ * tn->full_children) >= ++ * inflate_threshold * tnode_child_length(tn) * 2 ++ * ++ * shorten again: ++ * 50 * (tn->full_children + tnode_child_length(tn) - ++ * tn->empty_children) >= inflate_threshold * ++ * tnode_child_length(tn) ++ * ++ */ ++ ++ /* Keep root node larger */ ++ ++ if (!node_parent(tn)) { ++ inflate_threshold_use = inflate_threshold_root; ++ halve_threshold_use = halve_threshold_root; ++ } else { ++ inflate_threshold_use = inflate_threshold; ++ halve_threshold_use = halve_threshold; ++ } ++ ++ max_work = MAX_WORK; ++ while ((tn->full_children > 0 && max_work-- && ++ 50 * (tn->full_children + tnode_child_length(tn) ++ - tn->empty_children) ++ >= inflate_threshold_use * tnode_child_length(tn))) { ++ ++ old_tn = tn; ++ tn = inflate(t, tn); ++ ++ if (IS_ERR(tn)) { ++ tn = old_tn; ++#ifdef CONFIG_IP_FIB_TRIE_STATS ++ this_cpu_inc(t->stats->resize_node_skipped); ++#endif ++ break; ++ } ++ } ++ ++ /* Return if at least one inflate is run */ ++ if (max_work != MAX_WORK) ++ return tn; ++ ++ /* ++ * Halve as long as the number of empty children in this ++ * node is above threshold. ++ */ ++ ++ max_work = MAX_WORK; ++ while (tn->bits > 1 && max_work-- && ++ 100 * (tnode_child_length(tn) - tn->empty_children) < ++ halve_threshold_use * tnode_child_length(tn)) { ++ ++ old_tn = tn; ++ tn = halve(t, tn); ++ if (IS_ERR(tn)) { ++ tn = old_tn; ++#ifdef CONFIG_IP_FIB_TRIE_STATS ++ this_cpu_inc(t->stats->resize_node_skipped); ++#endif ++ break; ++ } ++ } ++ ++ ++ /* Only one child remains */ ++ if (tn->empty_children == (tnode_child_length(tn) - 1)) { ++ unsigned long i; ++one_child: ++ for (i = tnode_child_length(tn); !n && i;) ++ n = tnode_get_child(tn, --i); ++no_children: ++ /* compress one level */ ++ node_set_parent(n, NULL); ++ tnode_free_safe(tn); ++ return n; ++ } ++ return tn; ++} ++ + /* readside must use rcu_read_lock currently dump routines + via get_fa_head and dump */ + diff --git a/target/linux/generic/patches-3.18/080-13-fib_trie-Add-functions-should_inflate-and-should_hal.patch b/target/linux/generic/patches-3.18/080-13-fib_trie-Add-functions-should_inflate-and-should_hal.patch new file mode 100644 index 0000000000..42c0394689 --- /dev/null +++ b/target/linux/generic/patches-3.18/080-13-fib_trie-Add-functions-should_inflate-and-should_hal.patch @@ -0,0 +1,250 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Wed, 31 Dec 2014 10:56:37 -0800 +Subject: [PATCH] fib_trie: Add functions should_inflate and should_halve + +This change pulls the logic for if we should inflate/halve the nodes out +into separate functions. It also addresses what I believe is a bug where 1 +full node is all that is needed to keep a node from ever being halved. + +Simple script to reproduce the issue: + modprobe dummy; ifconfig dummy0 up + for i in `seq 0 255`; do ifconfig dummy0:$i 10.0.${i}.1/24 up; done + ifconfig dummy0:256 10.0.255.33/16 up + for i in `seq 0 254`; do ifconfig dummy0:$i down; done + +Results from /proc/net/fib_triestat +Before: + Local: + Aver depth: 3.00 + Max depth: 4 + Leaves: 17 + Prefixes: 18 + Internal nodes: 11 + 1: 8 2: 2 10: 1 + Pointers: 1048 + Null ptrs: 1021 + Total size: 11 kB +After: + Local: + Aver depth: 3.41 + Max depth: 5 + Leaves: 17 + Prefixes: 18 + Internal nodes: 12 + 1: 8 2: 3 3: 1 + Pointers: 36 + Null ptrs: 8 + Total size: 3 kB + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -647,12 +647,94 @@ nomem: + return ERR_PTR(-ENOMEM); + } + ++/* From "Implementing a dynamic compressed trie" by Stefan Nilsson of ++ * the Helsinki University of Technology and Matti Tikkanen of Nokia ++ * Telecommunications, page 6: ++ * "A node is doubled if the ratio of non-empty children to all ++ * children in the *doubled* node is at least 'high'." ++ * ++ * 'high' in this instance is the variable 'inflate_threshold'. It ++ * is expressed as a percentage, so we multiply it with ++ * tnode_child_length() and instead of multiplying by 2 (since the ++ * child array will be doubled by inflate()) and multiplying ++ * the left-hand side by 100 (to handle the percentage thing) we ++ * multiply the left-hand side by 50. ++ * ++ * The left-hand side may look a bit weird: tnode_child_length(tn) ++ * - tn->empty_children is of course the number of non-null children ++ * in the current node. tn->full_children is the number of "full" ++ * children, that is non-null tnodes with a skip value of 0. ++ * All of those will be doubled in the resulting inflated tnode, so ++ * we just count them one extra time here. ++ * ++ * A clearer way to write this would be: ++ * ++ * to_be_doubled = tn->full_children; ++ * not_to_be_doubled = tnode_child_length(tn) - tn->empty_children - ++ * tn->full_children; ++ * ++ * new_child_length = tnode_child_length(tn) * 2; ++ * ++ * new_fill_factor = 100 * (not_to_be_doubled + 2*to_be_doubled) / ++ * new_child_length; ++ * if (new_fill_factor >= inflate_threshold) ++ * ++ * ...and so on, tho it would mess up the while () loop. ++ * ++ * anyway, ++ * 100 * (not_to_be_doubled + 2*to_be_doubled) / new_child_length >= ++ * inflate_threshold ++ * ++ * avoid a division: ++ * 100 * (not_to_be_doubled + 2*to_be_doubled) >= ++ * inflate_threshold * new_child_length ++ * ++ * expand not_to_be_doubled and to_be_doubled, and shorten: ++ * 100 * (tnode_child_length(tn) - tn->empty_children + ++ * tn->full_children) >= inflate_threshold * new_child_length ++ * ++ * expand new_child_length: ++ * 100 * (tnode_child_length(tn) - tn->empty_children + ++ * tn->full_children) >= ++ * inflate_threshold * tnode_child_length(tn) * 2 ++ * ++ * shorten again: ++ * 50 * (tn->full_children + tnode_child_length(tn) - ++ * tn->empty_children) >= inflate_threshold * ++ * tnode_child_length(tn) ++ * ++ */ ++static bool should_inflate(const struct tnode *tn) ++{ ++ unsigned long used = tnode_child_length(tn); ++ unsigned long threshold = used; ++ ++ /* Keep root node larger */ ++ threshold *= node_parent(tn) ? inflate_threshold : ++ inflate_threshold_root; ++ used += tn->full_children; ++ used -= tn->empty_children; ++ ++ return tn->pos && ((50 * used) >= threshold); ++} ++ ++static bool should_halve(const struct tnode *tn) ++{ ++ unsigned long used = tnode_child_length(tn); ++ unsigned long threshold = used; ++ ++ /* Keep root node larger */ ++ threshold *= node_parent(tn) ? halve_threshold : ++ halve_threshold_root; ++ used -= tn->empty_children; ++ ++ return (tn->bits > 1) && ((100 * used) < threshold); ++} ++ + #define MAX_WORK 10 + static struct tnode *resize(struct trie *t, struct tnode *tn) + { + struct tnode *old_tn, *n = NULL; +- int inflate_threshold_use; +- int halve_threshold_use; + int max_work; + + if (!tn) +@@ -668,86 +750,12 @@ static struct tnode *resize(struct trie + /* One child */ + if (tn->empty_children == (tnode_child_length(tn) - 1)) + goto one_child; +- /* +- * Double as long as the resulting node has a number of +- * nonempty nodes that are above the threshold. +- */ + +- /* +- * From "Implementing a dynamic compressed trie" by Stefan Nilsson of +- * the Helsinki University of Technology and Matti Tikkanen of Nokia +- * Telecommunications, page 6: +- * "A node is doubled if the ratio of non-empty children to all +- * children in the *doubled* node is at least 'high'." +- * +- * 'high' in this instance is the variable 'inflate_threshold'. It +- * is expressed as a percentage, so we multiply it with +- * tnode_child_length() and instead of multiplying by 2 (since the +- * child array will be doubled by inflate()) and multiplying +- * the left-hand side by 100 (to handle the percentage thing) we +- * multiply the left-hand side by 50. +- * +- * The left-hand side may look a bit weird: tnode_child_length(tn) +- * - tn->empty_children is of course the number of non-null children +- * in the current node. tn->full_children is the number of "full" +- * children, that is non-null tnodes with a skip value of 0. +- * All of those will be doubled in the resulting inflated tnode, so +- * we just count them one extra time here. +- * +- * A clearer way to write this would be: +- * +- * to_be_doubled = tn->full_children; +- * not_to_be_doubled = tnode_child_length(tn) - tn->empty_children - +- * tn->full_children; +- * +- * new_child_length = tnode_child_length(tn) * 2; +- * +- * new_fill_factor = 100 * (not_to_be_doubled + 2*to_be_doubled) / +- * new_child_length; +- * if (new_fill_factor >= inflate_threshold) +- * +- * ...and so on, tho it would mess up the while () loop. +- * +- * anyway, +- * 100 * (not_to_be_doubled + 2*to_be_doubled) / new_child_length >= +- * inflate_threshold +- * +- * avoid a division: +- * 100 * (not_to_be_doubled + 2*to_be_doubled) >= +- * inflate_threshold * new_child_length +- * +- * expand not_to_be_doubled and to_be_doubled, and shorten: +- * 100 * (tnode_child_length(tn) - tn->empty_children + +- * tn->full_children) >= inflate_threshold * new_child_length +- * +- * expand new_child_length: +- * 100 * (tnode_child_length(tn) - tn->empty_children + +- * tn->full_children) >= +- * inflate_threshold * tnode_child_length(tn) * 2 +- * +- * shorten again: +- * 50 * (tn->full_children + tnode_child_length(tn) - +- * tn->empty_children) >= inflate_threshold * +- * tnode_child_length(tn) +- * ++ /* Double as long as the resulting node has a number of ++ * nonempty nodes that are above the threshold. + */ +- +- /* Keep root node larger */ +- +- if (!node_parent(tn)) { +- inflate_threshold_use = inflate_threshold_root; +- halve_threshold_use = halve_threshold_root; +- } else { +- inflate_threshold_use = inflate_threshold; +- halve_threshold_use = halve_threshold; +- } +- + max_work = MAX_WORK; +- while ((tn->full_children > 0 && max_work-- && +- 50 * (tn->full_children + tnode_child_length(tn) +- - tn->empty_children) +- >= inflate_threshold_use * tnode_child_length(tn))) { +- ++ while (should_inflate(tn) && max_work--) { + old_tn = tn; + tn = inflate(t, tn); + +@@ -764,16 +772,11 @@ static struct tnode *resize(struct trie + if (max_work != MAX_WORK) + return tn; + +- /* +- * Halve as long as the number of empty children in this ++ /* Halve as long as the number of empty children in this + * node is above threshold. + */ +- + max_work = MAX_WORK; +- while (tn->bits > 1 && max_work-- && +- 100 * (tnode_child_length(tn) - tn->empty_children) < +- halve_threshold_use * tnode_child_length(tn)) { +- ++ while (should_halve(tn) && max_work--) { + old_tn = tn; + tn = halve(t, tn); + if (IS_ERR(tn)) { diff --git a/target/linux/generic/patches-3.18/080-14-fib_trie-Push-assignment-of-child-to-parent-down-int.patch b/target/linux/generic/patches-3.18/080-14-fib_trie-Push-assignment-of-child-to-parent-down-int.patch new file mode 100644 index 0000000000..0e87a7d08e --- /dev/null +++ b/target/linux/generic/patches-3.18/080-14-fib_trie-Push-assignment-of-child-to-parent-down-int.patch @@ -0,0 +1,336 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Wed, 31 Dec 2014 10:56:43 -0800 +Subject: [PATCH] fib_trie: Push assignment of child to parent down into + inflate/halve + +This change makes it so that the assignment of the tnode to the parent is +handled directly within whatever function is currently handling the node be +it inflate, halve, or resize. By doing this we can avoid some of the need +to set NULL pointers in the tree while we are resizing the subnodes. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -146,9 +146,7 @@ struct trie { + #endif + }; + +-static void tnode_put_child_reorg(struct tnode *tn, unsigned long i, +- struct tnode *n, int wasfull); +-static struct tnode *resize(struct trie *t, struct tnode *tn); ++static void resize(struct trie *t, struct tnode *tn); + /* tnodes to free after resize(); protected by RTNL */ + static struct callback_head *tnode_free_head; + static size_t tnode_free_size; +@@ -396,22 +394,13 @@ static inline int tnode_full(const struc + return n && ((n->pos + n->bits) == tn->pos) && IS_TNODE(n); + } + +-static inline void put_child(struct tnode *tn, unsigned long i, +- struct tnode *n) +-{ +- tnode_put_child_reorg(tn, i, n, -1); +-} +- +- /* +- * Add a child at position i overwriting the old value. +- * Update the value of full_children and empty_children. +- */ +- +-static void tnode_put_child_reorg(struct tnode *tn, unsigned long i, +- struct tnode *n, int wasfull) ++/* Add a child at position i overwriting the old value. ++ * Update the value of full_children and empty_children. ++ */ ++static void put_child(struct tnode *tn, unsigned long i, struct tnode *n) + { + struct tnode *chi = rtnl_dereference(tn->child[i]); +- int isfull; ++ int isfull, wasfull; + + BUG_ON(i >= tnode_child_length(tn)); + +@@ -422,10 +411,9 @@ static void tnode_put_child_reorg(struct + tn->empty_children--; + + /* update fullChildren */ +- if (wasfull == -1) +- wasfull = tnode_full(tn, chi); +- ++ wasfull = tnode_full(tn, chi); + isfull = tnode_full(tn, n); ++ + if (wasfull && !isfull) + tn->full_children--; + else if (!wasfull && isfull) +@@ -458,9 +446,10 @@ static void tnode_clean_free(struct tnod + node_free(tn); + } + +-static struct tnode *inflate(struct trie *t, struct tnode *oldtnode) ++static int inflate(struct trie *t, struct tnode *oldtnode) + { + unsigned long olen = tnode_child_length(oldtnode); ++ struct tnode *tp = node_parent(oldtnode); + struct tnode *tn; + unsigned long i; + t_key m; +@@ -468,9 +457,8 @@ static struct tnode *inflate(struct trie + pr_debug("In inflate\n"); + + tn = tnode_new(oldtnode->key, oldtnode->pos - 1, oldtnode->bits + 1); +- + if (!tn) +- return ERR_PTR(-ENOMEM); ++ return -ENOMEM; + + /* + * Preallocate and store tnodes before the actual work so we +@@ -564,30 +552,36 @@ static struct tnode *inflate(struct trie + put_child(left, j, rtnl_dereference(inode->child[j])); + put_child(right, j, rtnl_dereference(inode->child[j + size])); + } +- put_child(tn, 2*i, resize(t, left)); +- put_child(tn, 2*i+1, resize(t, right)); ++ ++ put_child(tn, 2 * i, left); ++ put_child(tn, 2 * i + 1, right); + + tnode_free_safe(inode); ++ ++ resize(t, left); ++ resize(t, right); + } ++ ++ put_child_root(tp, t, tn->key, tn); + tnode_free_safe(oldtnode); +- return tn; ++ return 0; + nomem: + tnode_clean_free(tn); +- return ERR_PTR(-ENOMEM); ++ return -ENOMEM; + } + +-static struct tnode *halve(struct trie *t, struct tnode *oldtnode) ++static int halve(struct trie *t, struct tnode *oldtnode) + { + unsigned long olen = tnode_child_length(oldtnode); ++ struct tnode *tp = node_parent(oldtnode); + struct tnode *tn, *left, *right; + int i; + + pr_debug("In halve\n"); + + tn = tnode_new(oldtnode->key, oldtnode->pos + 1, oldtnode->bits - 1); +- + if (!tn) +- return ERR_PTR(-ENOMEM); ++ return -ENOMEM; + + /* + * Preallocate and store tnodes before the actual work so we +@@ -606,8 +600,10 @@ static struct tnode *halve(struct trie * + + newn = tnode_new(left->key, oldtnode->pos, 1); + +- if (!newn) +- goto nomem; ++ if (!newn) { ++ tnode_clean_free(tn); ++ return -ENOMEM; ++ } + + put_child(tn, i/2, newn); + } +@@ -635,16 +631,18 @@ static struct tnode *halve(struct trie * + + /* Two nonempty children */ + newBinNode = tnode_get_child(tn, i/2); +- put_child(tn, i/2, NULL); + put_child(newBinNode, 0, left); + put_child(newBinNode, 1, right); +- put_child(tn, i/2, resize(t, newBinNode)); ++ ++ put_child(tn, i / 2, newBinNode); ++ ++ resize(t, newBinNode); + } ++ ++ put_child_root(tp, t, tn->key, tn); + tnode_free_safe(oldtnode); +- return tn; +-nomem: +- tnode_clean_free(tn); +- return ERR_PTR(-ENOMEM); ++ ++ return 0; + } + + /* From "Implementing a dynamic compressed trie" by Stefan Nilsson of +@@ -704,45 +702,48 @@ nomem: + * tnode_child_length(tn) + * + */ +-static bool should_inflate(const struct tnode *tn) ++static bool should_inflate(const struct tnode *tp, const struct tnode *tn) + { + unsigned long used = tnode_child_length(tn); + unsigned long threshold = used; + + /* Keep root node larger */ +- threshold *= node_parent(tn) ? inflate_threshold : +- inflate_threshold_root; ++ threshold *= tp ? inflate_threshold : inflate_threshold_root; + used += tn->full_children; + used -= tn->empty_children; + + return tn->pos && ((50 * used) >= threshold); + } + +-static bool should_halve(const struct tnode *tn) ++static bool should_halve(const struct tnode *tp, const struct tnode *tn) + { + unsigned long used = tnode_child_length(tn); + unsigned long threshold = used; + + /* Keep root node larger */ +- threshold *= node_parent(tn) ? halve_threshold : +- halve_threshold_root; ++ threshold *= tp ? halve_threshold : halve_threshold_root; + used -= tn->empty_children; + + return (tn->bits > 1) && ((100 * used) < threshold); + } + + #define MAX_WORK 10 +-static struct tnode *resize(struct trie *t, struct tnode *tn) ++static void resize(struct trie *t, struct tnode *tn) + { +- struct tnode *old_tn, *n = NULL; ++ struct tnode *tp = node_parent(tn), *n = NULL; ++ struct tnode __rcu **cptr; + int max_work; + +- if (!tn) +- return NULL; +- + pr_debug("In tnode_resize %p inflate_threshold=%d threshold=%d\n", + tn, inflate_threshold, halve_threshold); + ++ /* track the tnode via the pointer from the parent instead of ++ * doing it ourselves. This way we can let RCU fully do its ++ * thing without us interfering ++ */ ++ cptr = tp ? &tp->child[get_index(tn->key, tp)] : &t->trie; ++ BUG_ON(tn != rtnl_dereference(*cptr)); ++ + /* No children */ + if (tn->empty_children > (tnode_child_length(tn) - 1)) + goto no_children; +@@ -755,39 +756,35 @@ static struct tnode *resize(struct trie + * nonempty nodes that are above the threshold. + */ + max_work = MAX_WORK; +- while (should_inflate(tn) && max_work--) { +- old_tn = tn; +- tn = inflate(t, tn); +- +- if (IS_ERR(tn)) { +- tn = old_tn; ++ while (should_inflate(tp, tn) && max_work--) { ++ if (inflate(t, tn)) { + #ifdef CONFIG_IP_FIB_TRIE_STATS + this_cpu_inc(t->stats->resize_node_skipped); + #endif + break; + } ++ ++ tn = rtnl_dereference(*cptr); + } + + /* Return if at least one inflate is run */ + if (max_work != MAX_WORK) +- return tn; ++ return; + + /* Halve as long as the number of empty children in this + * node is above threshold. + */ + max_work = MAX_WORK; +- while (should_halve(tn) && max_work--) { +- old_tn = tn; +- tn = halve(t, tn); +- if (IS_ERR(tn)) { +- tn = old_tn; ++ while (should_halve(tp, tn) && max_work--) { ++ if (halve(t, tn)) { + #ifdef CONFIG_IP_FIB_TRIE_STATS + this_cpu_inc(t->stats->resize_node_skipped); + #endif + break; + } +- } + ++ tn = rtnl_dereference(*cptr); ++ } + + /* Only one child remains */ + if (tn->empty_children == (tnode_child_length(tn) - 1)) { +@@ -797,11 +794,12 @@ one_child: + n = tnode_get_child(tn, --i); + no_children: + /* compress one level */ +- node_set_parent(n, NULL); ++ put_child_root(tp, t, tn->key, n); ++ node_set_parent(n, tp); ++ ++ /* drop dead node */ + tnode_free_safe(tn); +- return n; + } +- return tn; + } + + /* readside must use rcu_read_lock currently dump routines +@@ -882,34 +880,19 @@ static struct tnode *fib_find_node(struc + + static void trie_rebalance(struct trie *t, struct tnode *tn) + { +- int wasfull; +- t_key cindex, key; + struct tnode *tp; + +- key = tn->key; +- +- while (tn != NULL && (tp = node_parent(tn)) != NULL) { +- cindex = get_index(key, tp); +- wasfull = tnode_full(tp, tnode_get_child(tp, cindex)); +- tn = resize(t, tn); +- +- tnode_put_child_reorg(tp, cindex, tn, wasfull); +- +- tp = node_parent(tn); +- if (!tp) +- rcu_assign_pointer(t->trie, tn); ++ while ((tp = node_parent(tn)) != NULL) { ++ resize(t, tn); + + tnode_free_flush(); +- if (!tp) +- break; + tn = tp; + } + + /* Handle last (top) tnode */ + if (IS_TNODE(tn)) +- tn = resize(t, tn); ++ resize(t, tn); + +- rcu_assign_pointer(t->trie, tn); + tnode_free_flush(); + } + diff --git a/target/linux/generic/patches-3.18/080-15-fib_trie-Push-tnode-flushing-down-to-inflate-halve.patch b/target/linux/generic/patches-3.18/080-15-fib_trie-Push-tnode-flushing-down-to-inflate-halve.patch new file mode 100644 index 0000000000..16ad37d5e2 --- /dev/null +++ b/target/linux/generic/patches-3.18/080-15-fib_trie-Push-tnode-flushing-down-to-inflate-halve.patch @@ -0,0 +1,237 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Wed, 31 Dec 2014 10:56:49 -0800 +Subject: [PATCH] fib_trie: Push tnode flushing down to inflate/halve + +This change pushes the tnode freeing down into the inflate and halve +functions. It makes more sense here as we have a better grasp of what is +going on and when a given cluster of nodes is ready to be freed. + +I believe this may address a bug in the freeing logic as well. For some +reason if the freelist got to a certain size we would call +synchronize_rcu(). I'm assuming that what they meant to do is call +synchronize_rcu() after they had handed off that much memory via +call_rcu(). As such that is what I have updated the behavior to be. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -147,8 +147,6 @@ struct trie { + }; + + static void resize(struct trie *t, struct tnode *tn); +-/* tnodes to free after resize(); protected by RTNL */ +-static struct callback_head *tnode_free_head; + static size_t tnode_free_size; + + /* +@@ -307,32 +305,6 @@ static struct tnode *tnode_alloc(size_t + return vzalloc(size); + } + +-static void tnode_free_safe(struct tnode *tn) +-{ +- BUG_ON(IS_LEAF(tn)); +- tn->rcu.next = tnode_free_head; +- tnode_free_head = &tn->rcu; +-} +- +-static void tnode_free_flush(void) +-{ +- struct callback_head *head; +- +- while ((head = tnode_free_head)) { +- struct tnode *tn = container_of(head, struct tnode, rcu); +- +- tnode_free_head = head->next; +- tnode_free_size += offsetof(struct tnode, child[1 << tn->bits]); +- +- node_free(tn); +- } +- +- if (tnode_free_size >= PAGE_SIZE * sync_pages) { +- tnode_free_size = 0; +- synchronize_rcu(); +- } +-} +- + static struct tnode *leaf_new(t_key key) + { + struct tnode *l = kmem_cache_alloc(trie_leaf_kmem, GFP_KERNEL); +@@ -433,17 +405,33 @@ static void put_child_root(struct tnode + rcu_assign_pointer(t->trie, n); + } + +-static void tnode_clean_free(struct tnode *tn) ++static inline void tnode_free_init(struct tnode *tn) + { +- struct tnode *tofree; +- unsigned long i; ++ tn->rcu.next = NULL; ++} ++ ++static inline void tnode_free_append(struct tnode *tn, struct tnode *n) ++{ ++ n->rcu.next = tn->rcu.next; ++ tn->rcu.next = &n->rcu; ++} + +- for (i = 0; i < tnode_child_length(tn); i++) { +- tofree = tnode_get_child(tn, i); +- if (tofree) +- node_free(tofree); ++static void tnode_free(struct tnode *tn) ++{ ++ struct callback_head *head = &tn->rcu; ++ ++ while (head) { ++ head = head->next; ++ tnode_free_size += offsetof(struct tnode, child[1 << tn->bits]); ++ node_free(tn); ++ ++ tn = container_of(head, struct tnode, rcu); ++ } ++ ++ if (tnode_free_size >= PAGE_SIZE * sync_pages) { ++ tnode_free_size = 0; ++ synchronize_rcu(); + } +- node_free(tn); + } + + static int inflate(struct trie *t, struct tnode *oldtnode) +@@ -476,20 +464,23 @@ static int inflate(struct trie *t, struc + inode->bits - 1); + if (!left) + goto nomem; ++ tnode_free_append(tn, left); + + right = tnode_new(inode->key | m, inode->pos, + inode->bits - 1); + +- if (!right) { +- node_free(left); ++ if (!right) + goto nomem; +- } ++ tnode_free_append(tn, right); + + put_child(tn, 2*i, left); + put_child(tn, 2*i+1, right); + } + } + ++ /* prepare oldtnode to be freed */ ++ tnode_free_init(oldtnode); ++ + for (i = 0; i < olen; i++) { + struct tnode *inode = tnode_get_child(oldtnode, i); + struct tnode *left, *right; +@@ -505,12 +496,13 @@ static int inflate(struct trie *t, struc + continue; + } + ++ /* drop the node in the old tnode free list */ ++ tnode_free_append(oldtnode, inode); ++ + /* An internal node with two children */ + if (inode->bits == 1) { + put_child(tn, 2*i, rtnl_dereference(inode->child[0])); + put_child(tn, 2*i+1, rtnl_dereference(inode->child[1])); +- +- tnode_free_safe(inode); + continue; + } + +@@ -556,17 +548,19 @@ static int inflate(struct trie *t, struc + put_child(tn, 2 * i, left); + put_child(tn, 2 * i + 1, right); + +- tnode_free_safe(inode); +- ++ /* resize child nodes */ + resize(t, left); + resize(t, right); + } + + put_child_root(tp, t, tn->key, tn); +- tnode_free_safe(oldtnode); ++ ++ /* we completed without error, prepare to free old node */ ++ tnode_free(oldtnode); + return 0; + nomem: +- tnode_clean_free(tn); ++ /* all pointers should be clean so we are done */ ++ tnode_free(tn); + return -ENOMEM; + } + +@@ -599,17 +593,20 @@ static int halve(struct trie *t, struct + struct tnode *newn; + + newn = tnode_new(left->key, oldtnode->pos, 1); +- + if (!newn) { +- tnode_clean_free(tn); ++ tnode_free(tn); + return -ENOMEM; + } ++ tnode_free_append(tn, newn); + + put_child(tn, i/2, newn); + } + + } + ++ /* prepare oldtnode to be freed */ ++ tnode_free_init(oldtnode); ++ + for (i = 0; i < olen; i += 2) { + struct tnode *newBinNode; + +@@ -636,11 +633,14 @@ static int halve(struct trie *t, struct + + put_child(tn, i / 2, newBinNode); + ++ /* resize child node */ + resize(t, newBinNode); + } + + put_child_root(tp, t, tn->key, tn); +- tnode_free_safe(oldtnode); ++ ++ /* all pointers should be clean so we are done */ ++ tnode_free(oldtnode); + + return 0; + } +@@ -798,7 +798,8 @@ no_children: + node_set_parent(n, tp); + + /* drop dead node */ +- tnode_free_safe(tn); ++ tnode_free_init(tn); ++ tnode_free(tn); + } + } + +@@ -884,16 +885,12 @@ static void trie_rebalance(struct trie * + + while ((tp = node_parent(tn)) != NULL) { + resize(t, tn); +- +- tnode_free_flush(); + tn = tp; + } + + /* Handle last (top) tnode */ + if (IS_TNODE(tn)) + resize(t, tn); +- +- tnode_free_flush(); + } + + /* only used from updater-side */ diff --git a/target/linux/generic/patches-3.18/080-16-fib_trie-inflate-halve-nodes-in-a-more-RCU-friendly-.patch b/target/linux/generic/patches-3.18/080-16-fib_trie-inflate-halve-nodes-in-a-more-RCU-friendly-.patch new file mode 100644 index 0000000000..caa2e0e4b1 --- /dev/null +++ b/target/linux/generic/patches-3.18/080-16-fib_trie-inflate-halve-nodes-in-a-more-RCU-friendly-.patch @@ -0,0 +1,345 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Wed, 31 Dec 2014 10:56:55 -0800 +Subject: [PATCH] fib_trie: inflate/halve nodes in a more RCU friendly + way + +This change pulls the node_set_parent functionality out of put_child_reorg +and instead leaves that to the function to take care of as well. By doing +this we can fully construct the new cluster of tnodes and all of the +pointers out of it before we start routing pointers into it. + +I am suspecting this will likely fix some concurency issues though I don't +have a good test to show as such. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -391,8 +391,6 @@ static void put_child(struct tnode *tn, + else if (!wasfull && isfull) + tn->full_children++; + +- node_set_parent(n, tn); +- + rcu_assign_pointer(tn->child[i], n); + } + +@@ -436,10 +434,8 @@ static void tnode_free(struct tnode *tn) + + static int inflate(struct trie *t, struct tnode *oldtnode) + { +- unsigned long olen = tnode_child_length(oldtnode); +- struct tnode *tp = node_parent(oldtnode); +- struct tnode *tn; +- unsigned long i; ++ struct tnode *inode, *node0, *node1, *tn, *tp; ++ unsigned long i, j, k; + t_key m; + + pr_debug("In inflate\n"); +@@ -448,43 +444,13 @@ static int inflate(struct trie *t, struc + if (!tn) + return -ENOMEM; + +- /* +- * Preallocate and store tnodes before the actual work so we +- * don't get into an inconsistent state if memory allocation +- * fails. In case of failure we return the oldnode and inflate +- * of tnode is ignored. ++ /* Assemble all of the pointers in our cluster, in this case that ++ * represents all of the pointers out of our allocated nodes that ++ * point to existing tnodes and the links between our allocated ++ * nodes. + */ +- for (i = 0, m = 1u << tn->pos; i < olen; i++) { +- struct tnode *inode = tnode_get_child(oldtnode, i); +- +- if (tnode_full(oldtnode, inode) && (inode->bits > 1)) { +- struct tnode *left, *right; +- +- left = tnode_new(inode->key & ~m, inode->pos, +- inode->bits - 1); +- if (!left) +- goto nomem; +- tnode_free_append(tn, left); +- +- right = tnode_new(inode->key | m, inode->pos, +- inode->bits - 1); +- +- if (!right) +- goto nomem; +- tnode_free_append(tn, right); +- +- put_child(tn, 2*i, left); +- put_child(tn, 2*i+1, right); +- } +- } +- +- /* prepare oldtnode to be freed */ +- tnode_free_init(oldtnode); +- +- for (i = 0; i < olen; i++) { +- struct tnode *inode = tnode_get_child(oldtnode, i); +- struct tnode *left, *right; +- unsigned long size, j; ++ for (i = tnode_child_length(oldtnode), m = 1u << tn->pos; i;) { ++ inode = tnode_get_child(oldtnode, --i); + + /* An empty child */ + if (inode == NULL) +@@ -496,65 +462,99 @@ static int inflate(struct trie *t, struc + continue; + } + +- /* drop the node in the old tnode free list */ +- tnode_free_append(oldtnode, inode); +- + /* An internal node with two children */ + if (inode->bits == 1) { +- put_child(tn, 2*i, rtnl_dereference(inode->child[0])); +- put_child(tn, 2*i+1, rtnl_dereference(inode->child[1])); ++ put_child(tn, 2 * i + 1, tnode_get_child(inode, 1)); ++ put_child(tn, 2 * i, tnode_get_child(inode, 0)); + continue; + } + +- /* An internal node with more than two children */ +- + /* We will replace this node 'inode' with two new +- * ones, 'left' and 'right', each with half of the ++ * ones, 'node0' and 'node1', each with half of the + * original children. The two new nodes will have + * a position one bit further down the key and this + * means that the "significant" part of their keys + * (see the discussion near the top of this file) + * will differ by one bit, which will be "0" in +- * left's key and "1" in right's key. Since we are ++ * node0's key and "1" in node1's key. Since we are + * moving the key position by one step, the bit that + * we are moving away from - the bit at position +- * (inode->pos) - is the one that will differ between +- * left and right. So... we synthesize that bit in the +- * two new keys. +- * The mask 'm' below will be a single "one" bit at +- * the position (inode->pos) ++ * (tn->pos) - is the one that will differ between ++ * node0 and node1. So... we synthesize that bit in the ++ * two new keys. + */ ++ node1 = tnode_new(inode->key | m, inode->pos, inode->bits - 1); ++ if (!node1) ++ goto nomem; ++ tnode_free_append(tn, node1); ++ ++ node0 = tnode_new(inode->key & ~m, inode->pos, inode->bits - 1); ++ if (!node0) ++ goto nomem; ++ tnode_free_append(tn, node0); ++ ++ /* populate child pointers in new nodes */ ++ for (k = tnode_child_length(inode), j = k / 2; j;) { ++ put_child(node1, --j, tnode_get_child(inode, --k)); ++ put_child(node0, j, tnode_get_child(inode, j)); ++ put_child(node1, --j, tnode_get_child(inode, --k)); ++ put_child(node0, j, tnode_get_child(inode, j)); ++ } ++ ++ /* link new nodes to parent */ ++ NODE_INIT_PARENT(node1, tn); ++ NODE_INIT_PARENT(node0, tn); ++ ++ /* link parent to nodes */ ++ put_child(tn, 2 * i + 1, node1); ++ put_child(tn, 2 * i, node0); ++ } ++ ++ /* setup the parent pointer into and out of this node */ ++ tp = node_parent(oldtnode); ++ NODE_INIT_PARENT(tn, tp); ++ put_child_root(tp, t, tn->key, tn); + +- /* Use the old key, but set the new significant +- * bit to zero. +- */ ++ /* prepare oldtnode to be freed */ ++ tnode_free_init(oldtnode); + +- left = tnode_get_child(tn, 2*i); +- put_child(tn, 2*i, NULL); ++ /* update all child nodes parent pointers to route to us */ ++ for (i = tnode_child_length(oldtnode); i;) { ++ inode = tnode_get_child(oldtnode, --i); + +- BUG_ON(!left); ++ /* A leaf or an internal node with skipped bits */ ++ if (!tnode_full(oldtnode, inode)) { ++ node_set_parent(inode, tn); ++ continue; ++ } + +- right = tnode_get_child(tn, 2*i+1); +- put_child(tn, 2*i+1, NULL); ++ /* drop the node in the old tnode free list */ ++ tnode_free_append(oldtnode, inode); + +- BUG_ON(!right); ++ /* fetch new nodes */ ++ node1 = tnode_get_child(tn, 2 * i + 1); ++ node0 = tnode_get_child(tn, 2 * i); + +- size = tnode_child_length(left); +- for (j = 0; j < size; j++) { +- put_child(left, j, rtnl_dereference(inode->child[j])); +- put_child(right, j, rtnl_dereference(inode->child[j + size])); ++ /* bits == 1 then node0 and node1 represent inode's children */ ++ if (inode->bits == 1) { ++ node_set_parent(node1, tn); ++ node_set_parent(node0, tn); ++ continue; + } + +- put_child(tn, 2 * i, left); +- put_child(tn, 2 * i + 1, right); ++ /* update parent pointers in child node's children */ ++ for (k = tnode_child_length(inode), j = k / 2; j;) { ++ node_set_parent(tnode_get_child(inode, --k), node1); ++ node_set_parent(tnode_get_child(inode, --j), node0); ++ node_set_parent(tnode_get_child(inode, --k), node1); ++ node_set_parent(tnode_get_child(inode, --j), node0); ++ } + + /* resize child nodes */ +- resize(t, left); +- resize(t, right); ++ resize(t, node1); ++ resize(t, node0); + } + +- put_child_root(tp, t, tn->key, tn); +- + /* we completed without error, prepare to free old node */ + tnode_free(oldtnode); + return 0; +@@ -566,10 +566,8 @@ nomem: + + static int halve(struct trie *t, struct tnode *oldtnode) + { +- unsigned long olen = tnode_child_length(oldtnode); +- struct tnode *tp = node_parent(oldtnode); +- struct tnode *tn, *left, *right; +- int i; ++ struct tnode *tn, *tp, *inode, *node0, *node1; ++ unsigned long i; + + pr_debug("In halve\n"); + +@@ -577,68 +575,64 @@ static int halve(struct trie *t, struct + if (!tn) + return -ENOMEM; + +- /* +- * Preallocate and store tnodes before the actual work so we +- * don't get into an inconsistent state if memory allocation +- * fails. In case of failure we return the oldnode and halve +- * of tnode is ignored. ++ /* Assemble all of the pointers in our cluster, in this case that ++ * represents all of the pointers out of our allocated nodes that ++ * point to existing tnodes and the links between our allocated ++ * nodes. + */ ++ for (i = tnode_child_length(oldtnode); i;) { ++ node1 = tnode_get_child(oldtnode, --i); ++ node0 = tnode_get_child(oldtnode, --i); + +- for (i = 0; i < olen; i += 2) { +- left = tnode_get_child(oldtnode, i); +- right = tnode_get_child(oldtnode, i+1); ++ /* At least one of the children is empty */ ++ if (!node1 || !node0) { ++ put_child(tn, i / 2, node1 ? : node0); ++ continue; ++ } + + /* Two nonempty children */ +- if (left && right) { +- struct tnode *newn; +- +- newn = tnode_new(left->key, oldtnode->pos, 1); +- if (!newn) { +- tnode_free(tn); +- return -ENOMEM; +- } +- tnode_free_append(tn, newn); +- +- put_child(tn, i/2, newn); ++ inode = tnode_new(node0->key, oldtnode->pos, 1); ++ if (!inode) { ++ tnode_free(tn); ++ return -ENOMEM; + } ++ tnode_free_append(tn, inode); + ++ /* initialize pointers out of node */ ++ put_child(inode, 1, node1); ++ put_child(inode, 0, node0); ++ NODE_INIT_PARENT(inode, tn); ++ ++ /* link parent to node */ ++ put_child(tn, i / 2, inode); + } + ++ /* setup the parent pointer out of and back into this node */ ++ tp = node_parent(oldtnode); ++ NODE_INIT_PARENT(tn, tp); ++ put_child_root(tp, t, tn->key, tn); ++ + /* prepare oldtnode to be freed */ + tnode_free_init(oldtnode); + +- for (i = 0; i < olen; i += 2) { +- struct tnode *newBinNode; +- +- left = tnode_get_child(oldtnode, i); +- right = tnode_get_child(oldtnode, i+1); +- +- /* At least one of the children is empty */ +- if (left == NULL) { +- if (right == NULL) /* Both are empty */ +- continue; +- put_child(tn, i/2, right); +- continue; +- } +- +- if (right == NULL) { +- put_child(tn, i/2, left); ++ /* update all of the child parent pointers */ ++ for (i = tnode_child_length(tn); i;) { ++ inode = tnode_get_child(tn, --i); ++ ++ /* only new tnodes will be considered "full" nodes */ ++ if (!tnode_full(tn, inode)) { ++ node_set_parent(inode, tn); + continue; + } + + /* Two nonempty children */ +- newBinNode = tnode_get_child(tn, i/2); +- put_child(newBinNode, 0, left); +- put_child(newBinNode, 1, right); +- +- put_child(tn, i / 2, newBinNode); ++ node_set_parent(tnode_get_child(inode, 1), inode); ++ node_set_parent(tnode_get_child(inode, 0), inode); + + /* resize child node */ +- resize(t, newBinNode); ++ resize(t, inode); + } + +- put_child_root(tp, t, tn->key, tn); +- + /* all pointers should be clean so we are done */ + tnode_free(oldtnode); + diff --git a/target/linux/generic/patches-3.18/080-17-fib_trie-Remove-checks-for-index-tnode_child_length-.patch b/target/linux/generic/patches-3.18/080-17-fib_trie-Remove-checks-for-index-tnode_child_length-.patch new file mode 100644 index 0000000000..8f7c671ac6 --- /dev/null +++ b/target/linux/generic/patches-3.18/080-17-fib_trie-Remove-checks-for-index-tnode_child_length-.patch @@ -0,0 +1,95 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Wed, 31 Dec 2014 10:57:02 -0800 +Subject: [PATCH] fib_trie: Remove checks for index >= tnode_child_length + from tnode_get_child + +For some reason the compiler doesn't seem to understand that when we are in +a loop that runs from tnode_child_length - 1 to 0 we don't expect the value +of tn->bits to change. As such every call to tnode_get_child was rerunning +tnode_chile_length which ended up consuming quite a bit of space in the +resultant assembly code. + +I have gone though and verified that in all cases where tnode_get_child +is used we are either winding though a fixed loop from tnode_child_length - +1 to 0, or are in a fastpath case where we are verifying the value by +either checking for any remaining bits after shifting index by bits and +testing for leaf, or by using tnode_child_length. + +size net/ipv4/fib_trie.o +Before: + text data bss dec hex filename + 15506 376 8 15890 3e12 net/ipv4/fib_trie.o + +After: + text data bss dec hex filename + 14827 376 8 15211 3b6b net/ipv4/fib_trie.o + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -186,8 +186,6 @@ static inline unsigned long tnode_child_ + static inline struct tnode *tnode_get_child(const struct tnode *tn, + unsigned long i) + { +- BUG_ON(i >= tnode_child_length(tn)); +- + return rtnl_dereference(tn->child[i]); + } + +@@ -195,8 +193,6 @@ static inline struct tnode *tnode_get_ch + static inline struct tnode *tnode_get_child_rcu(const struct tnode *tn, + unsigned long i) + { +- BUG_ON(i >= tnode_child_length(tn)); +- + return rcu_dereference_rtnl(tn->child[i]); + } + +@@ -371,7 +367,7 @@ static inline int tnode_full(const struc + */ + static void put_child(struct tnode *tn, unsigned long i, struct tnode *n) + { +- struct tnode *chi = rtnl_dereference(tn->child[i]); ++ struct tnode *chi = tnode_get_child(tn, i); + int isfull, wasfull; + + BUG_ON(i >= tnode_child_length(tn)); +@@ -867,7 +863,7 @@ static struct tnode *fib_find_node(struc + if (IS_LEAF(n)) + break; + +- n = rcu_dereference_rtnl(n->child[index]); ++ n = tnode_get_child_rcu(n, index); + } + + return n; +@@ -934,7 +930,7 @@ static struct list_head *fib_insert_node + } + + tp = n; +- n = rcu_dereference_rtnl(n->child[index]); ++ n = tnode_get_child_rcu(n, index); + } + + l = leaf_new(key); +@@ -1215,7 +1211,7 @@ int fib_table_lookup(struct fib_table *t + cindex = index; + } + +- n = rcu_dereference(n->child[index]); ++ n = tnode_get_child_rcu(n, index); + if (unlikely(!n)) + goto backtrace; + } +@@ -1835,7 +1831,7 @@ static void trie_collect_stats(struct tr + if (n->bits < MAX_STAT_DEPTH) + s->nodesizes[n->bits]++; + +- for (i = 0; i < tnode_child_length(n); i++) { ++ for (i = tnode_child_length(n); i--;) { + if (!rcu_access_pointer(n->child[i])) + s->nullpointers++; + } diff --git a/target/linux/generic/patches-3.18/080-18-fib_trie-Add-tracking-value-for-suffix-length.patch b/target/linux/generic/patches-3.18/080-18-fib_trie-Add-tracking-value-for-suffix-length.patch new file mode 100644 index 0000000000..c9cd1cff7f --- /dev/null +++ b/target/linux/generic/patches-3.18/080-18-fib_trie-Add-tracking-value-for-suffix-length.patch @@ -0,0 +1,234 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Wed, 31 Dec 2014 10:57:08 -0800 +Subject: [PATCH] fib_trie: Add tracking value for suffix length + +This change adds a tracking value for the maximum suffix length of all +prefixes stored in any given tnode. With this value we can determine if we +need to backtrace or not based on if the suffix is greater than the pos +value. + +By doing this we can reduce the CPU overhead for lookups in the local table +as many of the prefixes there are 32b long and have a suffix length of 0 +meaning we can immediately backtrace to the root node without needing to +test any of the nodes between it and where we ended up. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -96,6 +96,7 @@ struct tnode { + t_key key; + unsigned char bits; /* 2log(KEYLENGTH) bits needed */ + unsigned char pos; /* 2log(KEYLENGTH) bits needed */ ++ unsigned char slen; + struct tnode __rcu *parent; + struct rcu_head rcu; + union { +@@ -311,6 +312,7 @@ static struct tnode *leaf_new(t_key key) + * as the nodes are searched + */ + l->key = key; ++ l->slen = 0; + l->pos = 0; + /* set bits to 0 indicating we are not a tnode */ + l->bits = 0; +@@ -342,6 +344,7 @@ static struct tnode *tnode_new(t_key key + + if (tn) { + tn->parent = NULL; ++ tn->slen = pos; + tn->pos = pos; + tn->bits = bits; + tn->key = (shift < KEYLENGTH) ? (key >> shift) << shift : 0; +@@ -387,6 +390,9 @@ static void put_child(struct tnode *tn, + else if (!wasfull && isfull) + tn->full_children++; + ++ if (n && (tn->slen < n->slen)) ++ tn->slen = n->slen; ++ + rcu_assign_pointer(tn->child[i], n); + } + +@@ -635,6 +641,41 @@ static int halve(struct trie *t, struct + return 0; + } + ++static unsigned char update_suffix(struct tnode *tn) ++{ ++ unsigned char slen = tn->pos; ++ unsigned long stride, i; ++ ++ /* search though the list of children looking for nodes that might ++ * have a suffix greater than the one we currently have. This is ++ * why we start with a stride of 2 since a stride of 1 would ++ * represent the nodes with suffix length equal to tn->pos ++ */ ++ for (i = 0, stride = 0x2ul ; i < tnode_child_length(tn); i += stride) { ++ struct tnode *n = tnode_get_child(tn, i); ++ ++ if (!n || (n->slen <= slen)) ++ continue; ++ ++ /* update stride and slen based on new value */ ++ stride <<= (n->slen - slen); ++ slen = n->slen; ++ i &= ~(stride - 1); ++ ++ /* if slen covers all but the last bit we can stop here ++ * there will be nothing longer than that since only node ++ * 0 and 1 << (bits - 1) could have that as their suffix ++ * length. ++ */ ++ if ((slen + 1) >= (tn->pos + tn->bits)) ++ break; ++ } ++ ++ tn->slen = slen; ++ ++ return slen; ++} ++ + /* From "Implementing a dynamic compressed trie" by Stefan Nilsson of + * the Helsinki University of Technology and Matti Tikkanen of Nokia + * Telecommunications, page 6: +@@ -790,6 +831,19 @@ no_children: + /* drop dead node */ + tnode_free_init(tn); + tnode_free(tn); ++ return; ++ } ++ ++ /* Return if at least one deflate was run */ ++ if (max_work != MAX_WORK) ++ return; ++ ++ /* push the suffix length to the parent node */ ++ if (tn->slen > tn->pos) { ++ unsigned char slen = update_suffix(tn); ++ ++ if (tp && (slen > tp->slen)) ++ tp->slen = slen; + } + } + +@@ -818,8 +872,58 @@ static inline struct list_head *get_fa_h + return &li->falh; + } + +-static void insert_leaf_info(struct hlist_head *head, struct leaf_info *new) ++static void leaf_pull_suffix(struct tnode *l) + { ++ struct tnode *tp = node_parent(l); ++ ++ while (tp && (tp->slen > tp->pos) && (tp->slen > l->slen)) { ++ if (update_suffix(tp) > l->slen) ++ break; ++ tp = node_parent(tp); ++ } ++} ++ ++static void leaf_push_suffix(struct tnode *l) ++{ ++ struct tnode *tn = node_parent(l); ++ ++ /* if this is a new leaf then tn will be NULL and we can sort ++ * out parent suffix lengths as a part of trie_rebalance ++ */ ++ while (tn && (tn->slen < l->slen)) { ++ tn->slen = l->slen; ++ tn = node_parent(tn); ++ } ++} ++ ++static void remove_leaf_info(struct tnode *l, struct leaf_info *old) ++{ ++ struct hlist_node *prev; ++ ++ /* record the location of the pointer to this object */ ++ prev = rtnl_dereference(hlist_pprev_rcu(&old->hlist)); ++ ++ /* remove the leaf info from the list */ ++ hlist_del_rcu(&old->hlist); ++ ++ /* if we emptied the list this leaf will be freed and we can sort ++ * out parent suffix lengths as a part of trie_rebalance ++ */ ++ if (hlist_empty(&l->list)) ++ return; ++ ++ /* if we removed the tail then we need to update slen */ ++ if (!rcu_access_pointer(hlist_next_rcu(prev))) { ++ struct leaf_info *li = hlist_entry(prev, typeof(*li), hlist); ++ ++ l->slen = KEYLENGTH - li->plen; ++ leaf_pull_suffix(l); ++ } ++} ++ ++static void insert_leaf_info(struct tnode *l, struct leaf_info *new) ++{ ++ struct hlist_head *head = &l->list; + struct leaf_info *li = NULL, *last = NULL; + + if (hlist_empty(head)) { +@@ -836,6 +940,12 @@ static void insert_leaf_info(struct hlis + else + hlist_add_before_rcu(&new->hlist, &li->hlist); + } ++ ++ /* if we added to the tail node then we need to update slen */ ++ if (!rcu_access_pointer(hlist_next_rcu(&new->hlist))) { ++ l->slen = KEYLENGTH - new->plen; ++ leaf_push_suffix(l); ++ } + } + + /* rcu_read_lock needs to be hold by caller from readside */ +@@ -925,7 +1035,7 @@ static struct list_head *fib_insert_node + /* we have found a leaf. Prefixes have already been compared */ + if (IS_LEAF(n)) { + /* Case 1: n is a leaf, and prefixes match*/ +- insert_leaf_info(&n->list, li); ++ insert_leaf_info(n, li); + return fa_head; + } + +@@ -939,7 +1049,7 @@ static struct list_head *fib_insert_node + return NULL; + } + +- insert_leaf_info(&l->list, li); ++ insert_leaf_info(l, li); + + /* Case 2: n is a LEAF or a TNODE and the key doesn't match. + * +@@ -1206,7 +1316,7 @@ int fib_table_lookup(struct fib_table *t + /* only record pn and cindex if we are going to be chopping + * bits later. Otherwise we are just wasting cycles. + */ +- if (index) { ++ if (n->slen > n->pos) { + pn = n; + cindex = index; + } +@@ -1225,7 +1335,7 @@ int fib_table_lookup(struct fib_table *t + * between the key and the prefix exist in the region of + * the lsb and higher in the prefix. + */ +- if (unlikely(prefix_mismatch(key, n))) ++ if (unlikely(prefix_mismatch(key, n)) || (n->slen == n->pos)) + goto backtrace; + + /* exit out and process leaf */ +@@ -1425,7 +1535,7 @@ int fib_table_delete(struct fib_table *t + tb->tb_num_default--; + + if (list_empty(fa_head)) { +- hlist_del_rcu(&li->hlist); ++ remove_leaf_info(l, li); + free_leaf_info(li); + } + diff --git a/target/linux/generic/patches-3.18/080-20-fib_trie-Fix-RCU-bug-and-merge-similar-bits-of-infla.patch b/target/linux/generic/patches-3.18/080-20-fib_trie-Fix-RCU-bug-and-merge-similar-bits-of-infla.patch new file mode 100644 index 0000000000..be837526a4 --- /dev/null +++ b/target/linux/generic/patches-3.18/080-20-fib_trie-Fix-RCU-bug-and-merge-similar-bits-of-infla.patch @@ -0,0 +1,267 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Thu, 22 Jan 2015 15:51:14 -0800 +Subject: [PATCH] fib_trie: Fix RCU bug and merge similar bits of inflate/halve + +This patch addresses two issues. + +The first issue is the fact that I believe I had the RCU freeing sequence +slightly out of order. As a result we could get into an issue if a caller +went into a child of a child of the new node, then backtraced into the to be +freed parent, and then attempted to access a child of a child that may have +been consumed in a resize of one of the new nodes children. To resolve this I +have moved the resize after we have freed the oldtnode. The only side effect +of this is that we will now be calling resize on more nodes in the case of +inflate due to the fact that we don't have a good way to test to see if a +full_tnode on the new node was there before or after the allocation. This +should have minimal impact however since the node should already be +correctly size so it is just the cost of calling should_inflate that we +will be taking on the node which is only a couple of cycles. + +The second issue is the fact that inflate and halve were essentially doing +the same thing after the new node was added to the trie replacing the old +one. As such it wasn't really necessary to keep the code in both functions +so I have split it out into two other functions, called replace and +update_children. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -396,8 +396,30 @@ static void put_child(struct tnode *tn, + rcu_assign_pointer(tn->child[i], n); + } + +-static void put_child_root(struct tnode *tp, struct trie *t, +- t_key key, struct tnode *n) ++static void update_children(struct tnode *tn) ++{ ++ unsigned long i; ++ ++ /* update all of the child parent pointers */ ++ for (i = tnode_child_length(tn); i;) { ++ struct tnode *inode = tnode_get_child(tn, --i); ++ ++ if (!inode) ++ continue; ++ ++ /* Either update the children of a tnode that ++ * already belongs to us or update the child ++ * to point to ourselves. ++ */ ++ if (node_parent(inode) == tn) ++ update_children(inode); ++ else ++ node_set_parent(inode, tn); ++ } ++} ++ ++static inline void put_child_root(struct tnode *tp, struct trie *t, ++ t_key key, struct tnode *n) + { + if (tp) + put_child(tp, get_index(key, tp), n); +@@ -434,10 +456,35 @@ static void tnode_free(struct tnode *tn) + } + } + ++static void replace(struct trie *t, struct tnode *oldtnode, struct tnode *tn) ++{ ++ struct tnode *tp = node_parent(oldtnode); ++ unsigned long i; ++ ++ /* setup the parent pointer out of and back into this node */ ++ NODE_INIT_PARENT(tn, tp); ++ put_child_root(tp, t, tn->key, tn); ++ ++ /* update all of the child parent pointers */ ++ update_children(tn); ++ ++ /* all pointers should be clean so we are done */ ++ tnode_free(oldtnode); ++ ++ /* resize children now that oldtnode is freed */ ++ for (i = tnode_child_length(tn); i;) { ++ struct tnode *inode = tnode_get_child(tn, --i); ++ ++ /* resize child node */ ++ if (tnode_full(tn, inode)) ++ resize(t, inode); ++ } ++} ++ + static int inflate(struct trie *t, struct tnode *oldtnode) + { +- struct tnode *inode, *node0, *node1, *tn, *tp; +- unsigned long i, j, k; ++ struct tnode *tn; ++ unsigned long i; + t_key m; + + pr_debug("In inflate\n"); +@@ -446,13 +493,18 @@ static int inflate(struct trie *t, struc + if (!tn) + return -ENOMEM; + ++ /* prepare oldtnode to be freed */ ++ tnode_free_init(oldtnode); ++ + /* Assemble all of the pointers in our cluster, in this case that + * represents all of the pointers out of our allocated nodes that + * point to existing tnodes and the links between our allocated + * nodes. + */ + for (i = tnode_child_length(oldtnode), m = 1u << tn->pos; i;) { +- inode = tnode_get_child(oldtnode, --i); ++ struct tnode *inode = tnode_get_child(oldtnode, --i); ++ struct tnode *node0, *node1; ++ unsigned long j, k; + + /* An empty child */ + if (inode == NULL) +@@ -464,6 +516,9 @@ static int inflate(struct trie *t, struc + continue; + } + ++ /* drop the node in the old tnode free list */ ++ tnode_free_append(oldtnode, inode); ++ + /* An internal node with two children */ + if (inode->bits == 1) { + put_child(tn, 2 * i + 1, tnode_get_child(inode, 1)); +@@ -488,9 +543,9 @@ static int inflate(struct trie *t, struc + node1 = tnode_new(inode->key | m, inode->pos, inode->bits - 1); + if (!node1) + goto nomem; +- tnode_free_append(tn, node1); ++ node0 = tnode_new(inode->key, inode->pos, inode->bits - 1); + +- node0 = tnode_new(inode->key & ~m, inode->pos, inode->bits - 1); ++ tnode_free_append(tn, node1); + if (!node0) + goto nomem; + tnode_free_append(tn, node0); +@@ -512,53 +567,9 @@ static int inflate(struct trie *t, struc + put_child(tn, 2 * i, node0); + } + +- /* setup the parent pointer into and out of this node */ +- tp = node_parent(oldtnode); +- NODE_INIT_PARENT(tn, tp); +- put_child_root(tp, t, tn->key, tn); +- +- /* prepare oldtnode to be freed */ +- tnode_free_init(oldtnode); +- +- /* update all child nodes parent pointers to route to us */ +- for (i = tnode_child_length(oldtnode); i;) { +- inode = tnode_get_child(oldtnode, --i); +- +- /* A leaf or an internal node with skipped bits */ +- if (!tnode_full(oldtnode, inode)) { +- node_set_parent(inode, tn); +- continue; +- } +- +- /* drop the node in the old tnode free list */ +- tnode_free_append(oldtnode, inode); +- +- /* fetch new nodes */ +- node1 = tnode_get_child(tn, 2 * i + 1); +- node0 = tnode_get_child(tn, 2 * i); ++ /* setup the parent pointers into and out of this node */ ++ replace(t, oldtnode, tn); + +- /* bits == 1 then node0 and node1 represent inode's children */ +- if (inode->bits == 1) { +- node_set_parent(node1, tn); +- node_set_parent(node0, tn); +- continue; +- } +- +- /* update parent pointers in child node's children */ +- for (k = tnode_child_length(inode), j = k / 2; j;) { +- node_set_parent(tnode_get_child(inode, --k), node1); +- node_set_parent(tnode_get_child(inode, --j), node0); +- node_set_parent(tnode_get_child(inode, --k), node1); +- node_set_parent(tnode_get_child(inode, --j), node0); +- } +- +- /* resize child nodes */ +- resize(t, node1); +- resize(t, node0); +- } +- +- /* we completed without error, prepare to free old node */ +- tnode_free(oldtnode); + return 0; + nomem: + /* all pointers should be clean so we are done */ +@@ -568,7 +579,7 @@ nomem: + + static int halve(struct trie *t, struct tnode *oldtnode) + { +- struct tnode *tn, *tp, *inode, *node0, *node1; ++ struct tnode *tn; + unsigned long i; + + pr_debug("In halve\n"); +@@ -577,14 +588,18 @@ static int halve(struct trie *t, struct + if (!tn) + return -ENOMEM; + ++ /* prepare oldtnode to be freed */ ++ tnode_free_init(oldtnode); ++ + /* Assemble all of the pointers in our cluster, in this case that + * represents all of the pointers out of our allocated nodes that + * point to existing tnodes and the links between our allocated + * nodes. + */ + for (i = tnode_child_length(oldtnode); i;) { +- node1 = tnode_get_child(oldtnode, --i); +- node0 = tnode_get_child(oldtnode, --i); ++ struct tnode *node1 = tnode_get_child(oldtnode, --i); ++ struct tnode *node0 = tnode_get_child(oldtnode, --i); ++ struct tnode *inode; + + /* At least one of the children is empty */ + if (!node1 || !node0) { +@@ -609,34 +624,8 @@ static int halve(struct trie *t, struct + put_child(tn, i / 2, inode); + } + +- /* setup the parent pointer out of and back into this node */ +- tp = node_parent(oldtnode); +- NODE_INIT_PARENT(tn, tp); +- put_child_root(tp, t, tn->key, tn); +- +- /* prepare oldtnode to be freed */ +- tnode_free_init(oldtnode); +- +- /* update all of the child parent pointers */ +- for (i = tnode_child_length(tn); i;) { +- inode = tnode_get_child(tn, --i); +- +- /* only new tnodes will be considered "full" nodes */ +- if (!tnode_full(tn, inode)) { +- node_set_parent(inode, tn); +- continue; +- } +- +- /* Two nonempty children */ +- node_set_parent(tnode_get_child(inode, 1), inode); +- node_set_parent(tnode_get_child(inode, 0), inode); +- +- /* resize child node */ +- resize(t, inode); +- } +- +- /* all pointers should be clean so we are done */ +- tnode_free(oldtnode); ++ /* setup the parent pointers into and out of this node */ ++ replace(t, oldtnode, tn); + + return 0; + } diff --git a/target/linux/generic/patches-3.18/080-21-fib_trie-Fall-back-to-slen-update-on-inflate-halve-f.patch b/target/linux/generic/patches-3.18/080-21-fib_trie-Fall-back-to-slen-update-on-inflate-halve-f.patch new file mode 100644 index 0000000000..058b33bf9d --- /dev/null +++ b/target/linux/generic/patches-3.18/080-21-fib_trie-Fall-back-to-slen-update-on-inflate-halve-f.patch @@ -0,0 +1,61 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Thu, 22 Jan 2015 15:51:20 -0800 +Subject: [PATCH] fib_trie: Fall back to slen update on inflate/halve failure + +This change corrects an issue where if inflate or halve fails we were +exiting the resize function without at least updating the slen for the +node. To correct this I have moved the update of max_size into the while +loop so that it is only decremented on a successful call to either inflate +or halve. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -752,7 +752,7 @@ static void resize(struct trie *t, struc + { + struct tnode *tp = node_parent(tn), *n = NULL; + struct tnode __rcu **cptr; +- int max_work; ++ int max_work = MAX_WORK; + + pr_debug("In tnode_resize %p inflate_threshold=%d threshold=%d\n", + tn, inflate_threshold, halve_threshold); +@@ -775,8 +775,7 @@ static void resize(struct trie *t, struc + /* Double as long as the resulting node has a number of + * nonempty nodes that are above the threshold. + */ +- max_work = MAX_WORK; +- while (should_inflate(tp, tn) && max_work--) { ++ while (should_inflate(tp, tn) && max_work) { + if (inflate(t, tn)) { + #ifdef CONFIG_IP_FIB_TRIE_STATS + this_cpu_inc(t->stats->resize_node_skipped); +@@ -784,6 +783,7 @@ static void resize(struct trie *t, struc + break; + } + ++ max_work--; + tn = rtnl_dereference(*cptr); + } + +@@ -794,8 +794,7 @@ static void resize(struct trie *t, struc + /* Halve as long as the number of empty children in this + * node is above threshold. + */ +- max_work = MAX_WORK; +- while (should_halve(tp, tn) && max_work--) { ++ while (should_halve(tp, tn) && max_work) { + if (halve(t, tn)) { + #ifdef CONFIG_IP_FIB_TRIE_STATS + this_cpu_inc(t->stats->resize_node_skipped); +@@ -803,6 +802,7 @@ static void resize(struct trie *t, struc + break; + } + ++ max_work--; + tn = rtnl_dereference(*cptr); + } + diff --git a/target/linux/generic/patches-3.18/080-22-fib_trie-Add-collapse-and-should_collapse-to-resize.patch b/target/linux/generic/patches-3.18/080-22-fib_trie-Add-collapse-and-should_collapse-to-resize.patch new file mode 100644 index 0000000000..afea33ff15 --- /dev/null +++ b/target/linux/generic/patches-3.18/080-22-fib_trie-Add-collapse-and-should_collapse-to-resize.patch @@ -0,0 +1,206 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Thu, 22 Jan 2015 15:51:26 -0800 +Subject: [PATCH] fib_trie: Add collapse() and should_collapse() to resize + +This patch really does two things. + +First it pulls the logic for determining if we should collapse one node out +of the tree and the actual code doing the collapse into a separate pair of +functions. This helps to make the changes to these areas more readable. + +Second it encodes the upper 32b of the empty_children value onto the +full_children value in the case of bits == KEYLENGTH. By doing this we are +able to handle the case of a 32b node where empty_children would appear to +be 0 when it was actually 1ul << 32. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -83,7 +83,8 @@ + + #define MAX_STAT_DEPTH 32 + +-#define KEYLENGTH (8*sizeof(t_key)) ++#define KEYLENGTH (8*sizeof(t_key)) ++#define KEY_MAX ((t_key)~0) + + typedef unsigned int t_key; + +@@ -102,8 +103,8 @@ struct tnode { + union { + /* The fields in this struct are valid if bits > 0 (TNODE) */ + struct { +- unsigned int full_children; /* KEYLENGTH bits needed */ +- unsigned int empty_children; /* KEYLENGTH bits needed */ ++ t_key empty_children; /* KEYLENGTH bits needed */ ++ t_key full_children; /* KEYLENGTH bits needed */ + struct tnode __rcu *child[0]; + }; + /* This list pointer if valid if bits == 0 (LEAF) */ +@@ -302,6 +303,16 @@ static struct tnode *tnode_alloc(size_t + return vzalloc(size); + } + ++static inline void empty_child_inc(struct tnode *n) ++{ ++ ++n->empty_children ? : ++n->full_children; ++} ++ ++static inline void empty_child_dec(struct tnode *n) ++{ ++ n->empty_children-- ? : n->full_children--; ++} ++ + static struct tnode *leaf_new(t_key key) + { + struct tnode *l = kmem_cache_alloc(trie_leaf_kmem, GFP_KERNEL); +@@ -335,7 +346,7 @@ static struct leaf_info *leaf_info_new(i + + static struct tnode *tnode_new(t_key key, int pos, int bits) + { +- size_t sz = offsetof(struct tnode, child[1 << bits]); ++ size_t sz = offsetof(struct tnode, child[1ul << bits]); + struct tnode *tn = tnode_alloc(sz); + unsigned int shift = pos + bits; + +@@ -348,8 +359,10 @@ static struct tnode *tnode_new(t_key key + tn->pos = pos; + tn->bits = bits; + tn->key = (shift < KEYLENGTH) ? (key >> shift) << shift : 0; +- tn->full_children = 0; +- tn->empty_children = 1<<bits; ++ if (bits == KEYLENGTH) ++ tn->full_children = 1; ++ else ++ tn->empty_children = 1ul << bits; + } + + pr_debug("AT %p s=%zu %zu\n", tn, sizeof(struct tnode), +@@ -375,11 +388,11 @@ static void put_child(struct tnode *tn, + + BUG_ON(i >= tnode_child_length(tn)); + +- /* update emptyChildren */ ++ /* update emptyChildren, overflow into fullChildren */ + if (n == NULL && chi != NULL) +- tn->empty_children++; +- else if (n != NULL && chi == NULL) +- tn->empty_children--; ++ empty_child_inc(tn); ++ if (n != NULL && chi == NULL) ++ empty_child_dec(tn); + + /* update fullChildren */ + wasfull = tnode_full(tn, chi); +@@ -630,6 +643,24 @@ static int halve(struct trie *t, struct + return 0; + } + ++static void collapse(struct trie *t, struct tnode *oldtnode) ++{ ++ struct tnode *n, *tp; ++ unsigned long i; ++ ++ /* scan the tnode looking for that one child that might still exist */ ++ for (n = NULL, i = tnode_child_length(oldtnode); !n && i;) ++ n = tnode_get_child(oldtnode, --i); ++ ++ /* compress one level */ ++ tp = node_parent(oldtnode); ++ put_child_root(tp, t, oldtnode->key, n); ++ node_set_parent(n, tp); ++ ++ /* drop dead node */ ++ node_free(oldtnode); ++} ++ + static unsigned char update_suffix(struct tnode *tn) + { + unsigned char slen = tn->pos; +@@ -729,10 +760,12 @@ static bool should_inflate(const struct + + /* Keep root node larger */ + threshold *= tp ? inflate_threshold : inflate_threshold_root; +- used += tn->full_children; + used -= tn->empty_children; ++ used += tn->full_children; + +- return tn->pos && ((50 * used) >= threshold); ++ /* if bits == KEYLENGTH then pos = 0, and will fail below */ ++ ++ return (used > 1) && tn->pos && ((50 * used) >= threshold); + } + + static bool should_halve(const struct tnode *tp, const struct tnode *tn) +@@ -744,13 +777,29 @@ static bool should_halve(const struct tn + threshold *= tp ? halve_threshold : halve_threshold_root; + used -= tn->empty_children; + +- return (tn->bits > 1) && ((100 * used) < threshold); ++ /* if bits == KEYLENGTH then used = 100% on wrap, and will fail below */ ++ ++ return (used > 1) && (tn->bits > 1) && ((100 * used) < threshold); ++} ++ ++static bool should_collapse(const struct tnode *tn) ++{ ++ unsigned long used = tnode_child_length(tn); ++ ++ used -= tn->empty_children; ++ ++ /* account for bits == KEYLENGTH case */ ++ if ((tn->bits == KEYLENGTH) && tn->full_children) ++ used -= KEY_MAX; ++ ++ /* One child or none, time to drop us from the trie */ ++ return used < 2; + } + + #define MAX_WORK 10 + static void resize(struct trie *t, struct tnode *tn) + { +- struct tnode *tp = node_parent(tn), *n = NULL; ++ struct tnode *tp = node_parent(tn); + struct tnode __rcu **cptr; + int max_work = MAX_WORK; + +@@ -764,14 +813,6 @@ static void resize(struct trie *t, struc + cptr = tp ? &tp->child[get_index(tn->key, tp)] : &t->trie; + BUG_ON(tn != rtnl_dereference(*cptr)); + +- /* No children */ +- if (tn->empty_children > (tnode_child_length(tn) - 1)) +- goto no_children; +- +- /* One child */ +- if (tn->empty_children == (tnode_child_length(tn) - 1)) +- goto one_child; +- + /* Double as long as the resulting node has a number of + * nonempty nodes that are above the threshold. + */ +@@ -807,19 +848,8 @@ static void resize(struct trie *t, struc + } + + /* Only one child remains */ +- if (tn->empty_children == (tnode_child_length(tn) - 1)) { +- unsigned long i; +-one_child: +- for (i = tnode_child_length(tn); !n && i;) +- n = tnode_get_child(tn, --i); +-no_children: +- /* compress one level */ +- put_child_root(tp, t, tn->key, n); +- node_set_parent(n, tp); +- +- /* drop dead node */ +- tnode_free_init(tn); +- tnode_free(tn); ++ if (should_collapse(tn)) { ++ collapse(t, tn); + return; + } + diff --git a/target/linux/generic/patches-3.18/080-23-fib_trie-Use-empty_children-instead-of-counting-empt.patch b/target/linux/generic/patches-3.18/080-23-fib_trie-Use-empty_children-instead-of-counting-empt.patch new file mode 100644 index 0000000000..160fbe1f3e --- /dev/null +++ b/target/linux/generic/patches-3.18/080-23-fib_trie-Use-empty_children-instead-of-counting-empt.patch @@ -0,0 +1,34 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Thu, 22 Jan 2015 15:51:33 -0800 +Subject: [PATCH] fib_trie: Use empty_children instead of counting empty nodes + in stats collection + +It doesn't make much sense to count the pointers ourselves when +empty_children already has a count for the number of NULL pointers stored +in the tnode. As such save ourselves the cycles and just use +empty_children. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -1954,16 +1954,10 @@ static void trie_collect_stats(struct tr + hlist_for_each_entry_rcu(li, &n->list, hlist) + ++s->prefixes; + } else { +- unsigned long i; +- + s->tnodes++; + if (n->bits < MAX_STAT_DEPTH) + s->nodesizes[n->bits]++; +- +- for (i = tnode_child_length(n); i--;) { +- if (!rcu_access_pointer(n->child[i])) +- s->nullpointers++; +- } ++ s->nullpointers += n->empty_children; + } + } + rcu_read_unlock(); diff --git a/target/linux/generic/patches-3.18/080-24-fib_trie-Move-fib_find_alias-to-file-where-it-is-use.patch b/target/linux/generic/patches-3.18/080-24-fib_trie-Move-fib_find_alias-to-file-where-it-is-use.patch new file mode 100644 index 0000000000..dfe716eda8 --- /dev/null +++ b/target/linux/generic/patches-3.18/080-24-fib_trie-Move-fib_find_alias-to-file-where-it-is-use.patch @@ -0,0 +1,79 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Thu, 22 Jan 2015 15:51:39 -0800 +Subject: [PATCH] fib_trie: Move fib_find_alias to file where it is used + +The function fib_find_alias is only accessed by functions in fib_trie.c as +such it makes sense to relocate it and cast it as static so that the +compiler can take advantage of optimizations it can do to it as a local +function. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_lookup.h ++++ b/net/ipv4/fib_lookup.h +@@ -32,7 +32,6 @@ int fib_dump_info(struct sk_buff *skb, u + unsigned int); + void rtmsg_fib(int event, __be32 key, struct fib_alias *fa, int dst_len, + u32 tb_id, const struct nl_info *info, unsigned int nlm_flags); +-struct fib_alias *fib_find_alias(struct list_head *fah, u8 tos, u32 prio); + + static inline void fib_result_assign(struct fib_result *res, + struct fib_info *fi) +--- a/net/ipv4/fib_semantics.c ++++ b/net/ipv4/fib_semantics.c +@@ -414,24 +414,6 @@ errout: + rtnl_set_sk_err(info->nl_net, RTNLGRP_IPV4_ROUTE, err); + } + +-/* Return the first fib alias matching TOS with +- * priority less than or equal to PRIO. +- */ +-struct fib_alias *fib_find_alias(struct list_head *fah, u8 tos, u32 prio) +-{ +- if (fah) { +- struct fib_alias *fa; +- list_for_each_entry(fa, fah, fa_list) { +- if (fa->fa_tos > tos) +- continue; +- if (fa->fa_info->fib_priority >= prio || +- fa->fa_tos < tos) +- return fa; +- } +- } +- return NULL; +-} +- + static int fib_detect_death(struct fib_info *fi, int order, + struct fib_info **last_resort, int *last_idx, + int dflt) +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -998,6 +998,26 @@ static struct tnode *fib_find_node(struc + return n; + } + ++/* Return the first fib alias matching TOS with ++ * priority less than or equal to PRIO. ++ */ ++static struct fib_alias *fib_find_alias(struct list_head *fah, u8 tos, u32 prio) ++{ ++ struct fib_alias *fa; ++ ++ if (!fah) ++ return NULL; ++ ++ list_for_each_entry(fa, fah, fa_list) { ++ if (fa->fa_tos > tos) ++ continue; ++ if (fa->fa_info->fib_priority >= prio || fa->fa_tos < tos) ++ return fa; ++ } ++ ++ return NULL; ++} ++ + static void trie_rebalance(struct trie *t, struct tnode *tn) + { + struct tnode *tp; diff --git a/target/linux/generic/patches-3.18/080-25-fib_trie-Various-clean-ups-for-handling-slen.patch b/target/linux/generic/patches-3.18/080-25-fib_trie-Various-clean-ups-for-handling-slen.patch new file mode 100644 index 0000000000..e47f253f35 --- /dev/null +++ b/target/linux/generic/patches-3.18/080-25-fib_trie-Various-clean-ups-for-handling-slen.patch @@ -0,0 +1,116 @@ +From: Alexander Duyck <alexander.h.duyck@redhat.com> +Date: Thu, 22 Jan 2015 15:51:45 -0800 +Subject: [PATCH] fib_trie: Various clean-ups for handling slen + +While doing further work on the fib_trie I noted a few items. + +First I was using calls that were far more complicated than they needed to +be for determining when to push/pull the suffix length. I have updated the +code to reflect the simplier logic. + +The second issue is that I realised we weren't necessarily handling the +case of a leaf_info struct surviving a flush. I have updated the logic so +that now we will call pull_suffix in the event of having a leaf info value +left in the leaf after flushing it. + +Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> +Signed-off-by: David S. Miller <davem@davemloft.net> +--- + +--- a/net/ipv4/fib_trie.c ++++ b/net/ipv4/fib_trie.c +@@ -917,27 +917,20 @@ static void leaf_push_suffix(struct tnod + + static void remove_leaf_info(struct tnode *l, struct leaf_info *old) + { +- struct hlist_node *prev; +- +- /* record the location of the pointer to this object */ +- prev = rtnl_dereference(hlist_pprev_rcu(&old->hlist)); ++ /* record the location of the previous list_info entry */ ++ struct hlist_node **pprev = old->hlist.pprev; ++ struct leaf_info *li = hlist_entry(pprev, typeof(*li), hlist.next); + + /* remove the leaf info from the list */ + hlist_del_rcu(&old->hlist); + +- /* if we emptied the list this leaf will be freed and we can sort +- * out parent suffix lengths as a part of trie_rebalance +- */ +- if (hlist_empty(&l->list)) ++ /* only access li if it is pointing at the last valid hlist_node */ ++ if (hlist_empty(&l->list) || (*pprev)) + return; + +- /* if we removed the tail then we need to update slen */ +- if (!rcu_access_pointer(hlist_next_rcu(prev))) { +- struct leaf_info *li = hlist_entry(prev, typeof(*li), hlist); +- +- l->slen = KEYLENGTH - li->plen; +- leaf_pull_suffix(l); +- } ++ /* update the trie with the latest suffix length */ ++ l->slen = KEYLENGTH - li->plen; ++ leaf_pull_suffix(l); + } + + static void insert_leaf_info(struct tnode *l, struct leaf_info *new) +@@ -961,7 +954,7 @@ static void insert_leaf_info(struct tnod + } + + /* if we added to the tail node then we need to update slen */ +- if (!rcu_access_pointer(hlist_next_rcu(&new->hlist))) { ++ if (l->slen < (KEYLENGTH - new->plen)) { + l->slen = KEYLENGTH - new->plen; + leaf_push_suffix(l); + } +@@ -1613,6 +1606,7 @@ static int trie_flush_leaf(struct tnode + struct hlist_head *lih = &l->list; + struct hlist_node *tmp; + struct leaf_info *li = NULL; ++ unsigned char plen = KEYLENGTH; + + hlist_for_each_entry_safe(li, tmp, lih, hlist) { + found += trie_flush_list(&li->falh); +@@ -1620,8 +1614,14 @@ static int trie_flush_leaf(struct tnode + if (list_empty(&li->falh)) { + hlist_del_rcu(&li->hlist); + free_leaf_info(li); ++ continue; + } ++ ++ plen = li->plen; + } ++ ++ l->slen = KEYLENGTH - plen; ++ + return found; + } + +@@ -1700,13 +1700,22 @@ int fib_table_flush(struct fib_table *tb + for (l = trie_firstleaf(t); l; l = trie_nextleaf(l)) { + found += trie_flush_leaf(l); + +- if (ll && hlist_empty(&ll->list)) +- trie_leaf_remove(t, ll); ++ if (ll) { ++ if (hlist_empty(&ll->list)) ++ trie_leaf_remove(t, ll); ++ else ++ leaf_pull_suffix(ll); ++ } ++ + ll = l; + } + +- if (ll && hlist_empty(&ll->list)) +- trie_leaf_remove(t, ll); ++ if (ll) { ++ if (hlist_empty(&ll->list)) ++ trie_leaf_remove(t, ll); ++ else ++ leaf_pull_suffix(ll); ++ } + + pr_debug("trie_flush found=%d\n", found); + return found; |