diff options
| author | Jeff Layton <jlayton@redhat.com> | 2013-06-21 08:58:19 -0400 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2013-06-29 12:57:45 +0400 |
| commit | 3999e49364193f7dbbba66e2be655fe91ba1fced (patch) | |
| tree | 5971637ac3b15d5d72797d4050ee35216b9fede1 /fs/locks.c | |
| parent | 48f74186546cd5929397856eab209ebcb5692d11 (diff) | |
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 'fs/locks.c')
| -rw-r--r-- | fs/locks.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/fs/locks.c b/fs/locks.c index 71d847cbbb63..6242e0b1c69c 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -521,10 +521,18 @@ locks_delete_global_locks(struct file_lock *fl) spin_unlock(&file_lock_lock); } +static unsigned long +posix_owner_key(struct file_lock *fl) +{ + if (fl->fl_lmops && fl->fl_lmops->lm_owner_key) + return fl->fl_lmops->lm_owner_key(fl); + return (unsigned long)fl->fl_owner; +} + static inline void locks_insert_global_blocked(struct file_lock *waiter) { - hash_add(blocked_hash, &waiter->fl_link, (unsigned long)waiter->fl_owner); + hash_add(blocked_hash, &waiter->fl_link, posix_owner_key(waiter)); } static inline void @@ -757,7 +765,7 @@ static struct file_lock *what_owner_is_waiting_for(struct file_lock *block_fl) { struct file_lock *fl; - hash_for_each_possible(blocked_hash, fl, fl_link, (unsigned long)block_fl->fl_owner) { + hash_for_each_possible(blocked_hash, fl, fl_link, posix_owner_key(block_fl)) { if (posix_same_owner(fl, block_fl)) return fl->fl_next; } |