diff options
Diffstat (limited to 'target/linux/generic/pending-3.18/080-19-fib_trie-Use-index-0ul-n-bits-instead-of-index-n-bit.patch')
| -rw-r--r-- | target/linux/generic/pending-3.18/080-19-fib_trie-Use-index-0ul-n-bits-instead-of-index-n-bit.patch | 52 |
1 files changed, 0 insertions, 52 deletions
diff --git a/target/linux/generic/pending-3.18/080-19-fib_trie-Use-index-0ul-n-bits-instead-of-index-n-bit.patch b/target/linux/generic/pending-3.18/080-19-fib_trie-Use-index-0ul-n-bits-instead-of-index-n-bit.patch deleted file mode 100644 index d5fc112563..0000000000 --- a/target/linux/generic/pending-3.18/080-19-fib_trie-Use-index-0ul-n-bits-instead-of-index-n-bit.patch +++ /dev/null @@ -1,52 +0,0 @@ -From: Alexander Duyck <alexander.h.duyck@redhat.com> -Date: Thu, 22 Jan 2015 15:51:08 -0800 -Subject: [PATCH] fib_trie: Use index & (~0ul << n->bits) instead of index >> - n->bits - -In doing performance testing and analysis of the changes I recently found -that by shifting the index I had created an unnecessary dependency. - -I have updated the code so that we instead shift a mask by bits and then -just test against that as that should save us about 2 CPU cycles since we -can generate the mask while the key and pos are being processed. - -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 -@@ -961,12 +961,12 @@ static struct tnode *fib_find_node(struc - * 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 -+ * if (index & (~0ul << bits)) - * we have a mismatch in skip bits and failed -+ * else -+ * we know the value is cindex - */ -- if (index >> n->bits) -+ if (index & (~0ul << n->bits)) - return NULL; - - /* we have found a leaf. Prefixes have already been compared */ -@@ -1301,12 +1301,12 @@ int fib_table_lookup(struct fib_table *t - * 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 -+ * if (index & (~0ul << bits)) - * we have a mismatch in skip bits and failed -+ * else -+ * we know the value is cindex - */ -- if (index >> n->bits) -+ if (index & (~0ul << n->bits)) - break; - - /* we have found a leaf. Prefixes have already been compared */ |