diff options
| author | Jeff Layton <jlayton@redhat.com> | 2013-06-21 12:58:19 (GMT) |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2013-06-29 08:57:45 (GMT) |
| commit | 3999e49364193f7dbbba66e2be655fe91ba1fced (patch) | |
| tree | 5971637ac3b15d5d72797d4050ee35216b9fede1 /include/linux/fs.h | |
| parent | 48f74186546cd5929397856eab209ebcb5692d11 (diff) | |
| download | linux-fsl-qoriq-3999e49364193f7dbbba66e2be655fe91ba1fced.tar.xz | |
locks: add a new "lm_owner_key" lock operation
Currently, the hashing that the locking code uses to add these values
to the blocked_hash is simply calculated using fl_owner field. That's
valid in most cases except for server-side lockd, which validates the
owner of a lock based on fl_owner and fl_pid.
In the case where you have a small number of NFS clients doing a lot
of locking between different processes, you could end up with all
the blocked requests sitting in a very small number of hash buckets.
Add a new lm_owner_key operation to the lock_manager_operations that
will generate an unsigned long to use as the key in the hashtable.
That function is only implemented for server-side lockd, and simply
XORs the fl_owner and fl_pid.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'include/linux/fs.h')
| -rw-r--r-- | include/linux/fs.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/fs.h b/include/linux/fs.h index fab064a..a137a73 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -908,6 +908,7 @@ struct file_lock_operations { struct lock_manager_operations { int (*lm_compare_owner)(struct file_lock *, struct file_lock *); + unsigned long (*lm_owner_key)(struct file_lock *); void (*lm_notify)(struct file_lock *); /* unblock callback */ int (*lm_grant)(struct file_lock *, struct file_lock *, int); void (*lm_break)(struct file_lock *); |