fs: prefetch inode data in dcache lookup
This makes single threaded git diff -1.25% +/- 0.05% elapsed time on my 2s12c24t Westmere system, and -0.86% +/- 0.05% on my 2s8c Barcelona, by prefetching the important first cacheline of the inode in while we do the actual name compare and other operations on the dentry. There was no measurable slowdown in the single file stat case, or the creat case (where negative dentries would be common). Signed-off-by: Nick Piggin <npiggin@kernel.dk>
This commit is contained in:
parent
4b936885ab
commit
e1bb578263
@ -1793,6 +1793,9 @@ struct dentry *__d_lookup_rcu(struct dentry *parent, struct qstr *name,
|
||||
tlen = dentry->d_name.len;
|
||||
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
|
||||
|
Loading…
Reference in New Issue
Block a user