From: Linus Torvalds Date: Thu, 21 Jul 2011 18:01:42 +0000 (-0700) Subject: vfs: drop conditional inode prefetch in __do_lookup_rcu X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=b91da88fed84843313a1b6fd1b1c834a24bbcf9e;p=linux-beck.git vfs: drop conditional inode prefetch in __do_lookup_rcu It seems to hurt performance in real life. Yes, the inode will be used later, but the conditional doesn't seem to predict all that well (negative dentries are not uncommon) and it looks like the cost of prefetching is simply higher than depending on the cache doing the right thing. As usual. Signed-off-by: Linus Torvalds --- diff --git a/fs/dcache.c b/fs/dcache.c index 6e4ea6d87774..fbdcbca40725 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -1813,8 +1813,6 @@ seqretry: tname = dentry->d_name.name; i = dentry->d_inode; prefetch(tname); - if (i) - prefetch(i); /* * This seqcount check is required to ensure name and * len are loaded atomically, so as not to walk off the