NFS: Optimise away unnecessary setattrs for open(O_TRUNC);

Currently, we will correctly optimise away a truncate that doesn't
change the file size. However, in the case of open(O_TRUNC), we
also want to optimise away the time changes.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
Trond Myklebust
2012-01-17 22:04:26 -05:00
parent 48c22eb210
commit 536e43d12b
3 changed files with 28 additions and 11 deletions

View File

@ -402,7 +402,7 @@ out_no_inode:
goto out;
}
#define NFS_VALID_ATTRS (ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_SIZE|ATTR_ATIME|ATTR_ATIME_SET|ATTR_MTIME|ATTR_MTIME_SET|ATTR_FILE)
#define NFS_VALID_ATTRS (ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_SIZE|ATTR_ATIME|ATTR_ATIME_SET|ATTR_MTIME|ATTR_MTIME_SET|ATTR_FILE|ATTR_OPEN)
int
nfs_setattr(struct dentry *dentry, struct iattr *attr)
@ -424,7 +424,7 @@ nfs_setattr(struct dentry *dentry, struct iattr *attr)
/* Optimization: if the end result is no change, don't RPC */
attr->ia_valid &= NFS_VALID_ATTRS;
if ((attr->ia_valid & ~ATTR_FILE) == 0)
if ((attr->ia_valid & ~(ATTR_FILE|ATTR_OPEN)) == 0)
return 0;
/* Write all dirty data */