path: root/fs
diff options
authorASANO Masahiro <>2006-08-22 20:06:02 -0400
committerTrond Myklebust <>2006-08-24 15:49:14 -0400
commita634904a7de0d3a0bc606f608007a34e8c05bfee (patch)
tree936d436adb118f7e7fbadd6eabf5296693861df0 /fs
parentddeff520f02b92128132c282c350fa72afffb84a (diff)
VFS: add lookup hint for network file systems
I'm trying to speeding up mkdir(2) for network file systems. A typical mkdir(2) calls two inode_operations: lookup and mkdir. The lookup operation would fail with ENOENT in common case. I think it is unnecessary because the subsequent mkdir operation can check it. In case of creat(2), lookup operation is called with the LOOKUP_CREATE flag, so individual filesystem can omit real lookup. e.g. nfs_lookup(). Here is a sample patch which uses LOOKUP_CREATE and O_EXCL on mkdir, symlink and mknod. This uses the gadget for creat(2). And here is the result of a benchmark on NFSv3. mkdir(2) 10,000 times: original 50.5 sec patched 29.0 sec Signed-off-by: ASANO Masahiro <> Signed-off-by: Andrew Morton <> Signed-off-by: Trond Myklebust <> (cherry picked from fab7bf44449b29f9d5572a5dd8adcf7c91d5bf0f commit)
Diffstat (limited to 'fs')
1 files changed, 2 insertions, 0 deletions
diff --git a/fs/namei.c b/fs/namei.c
index 55a131230f94..863166441bf3 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1767,6 +1767,8 @@ struct dentry *lookup_create(struct nameidata *nd, int is_dir)
if (nd->last_type != LAST_NORM)
goto fail;
nd->flags &= ~LOOKUP_PARENT;
+ nd->flags |= LOOKUP_CREATE;
+ nd-> = O_EXCL;
* Do the final lookup.