From 74d00a8c3849c1340efd713eb94b786e304c201f Mon Sep 17 00:00:00 2001 From: John Crispin Date: Sun, 25 Dec 2016 20:11:34 +0100 Subject: kernel: split patches folder up into backport, pending and hack folders * properly format/comment all patches * merge debloat patches * merge Kconfig patches * merge swconfig patches * merge hotplug patches * drop 200-fix_localversion.patch - upstream * drop 222-arm_zimage_none.patch - unused * drop 252-mv_cesa_depends.patch - no longer required * drop 410-mtd-move-forward-declaration-of-struct-mtd_info.patch - unused * drop 661-fq_codel_keep_dropped_stats.patch - outdated * drop 702-phy_add_aneg_done_function.patch - upstream * drop 840-rtc7301.patch - unused * drop 841-rtc_pt7c4338.patch - upstream * drop 921-use_preinit_as_init.patch - unused * drop spio-gpio-old and gpio-mmc - unused Signed-off-by: John Crispin --- ...e-index-0ul-n-bits-instead-of-index-n-bit.patch | 52 ++++++++++++++++++++++ 1 file changed, 52 insertions(+) create mode 100644 target/linux/generic/pending-3.18/080-19-fib_trie-Use-index-0ul-n-bits-instead-of-index-n-bit.patch (limited to 'target/linux/generic/pending-3.18/080-19-fib_trie-Use-index-0ul-n-bits-instead-of-index-n-bit.patch') 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 new file mode 100644 index 0000000000..d5fc112563 --- /dev/null +++ b/target/linux/generic/pending-3.18/080-19-fib_trie-Use-index-0ul-n-bits-instead-of-index-n-bit.patch @@ -0,0 +1,52 @@ +From: Alexander Duyck +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 +Signed-off-by: David S. Miller +--- + +--- 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 */ -- cgit v1.2.3