GFS2: Don't waste time locking lru_lock for non-lru glocks

Before this patch, glock_dq would call gfs2_glock_remove_from_lru.
For glocks that are never put on the LRU, such as the transaction
glock, this just takes the spin_lock, determines there's nothing to
be done because the list is empty, then unlocks again. This was
causing unnecessary lock contention on the lru_lock spin_lock.
This patch adds a check for GLOF_LRU in the glops before taking
the spin_lock.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
This commit is contained in:
Bob Peterson 2017-07-26 10:57:35 -05:00
parent 2d821a8b71
commit 645ebd49f0

View File

@ -150,6 +150,9 @@ void gfs2_glock_add_to_lru(struct gfs2_glock *gl)
static void gfs2_glock_remove_from_lru(struct gfs2_glock *gl)
{
if (!(gl->gl_ops->go_flags & GLOF_LRU))
return;
spin_lock(&lru_lock);
if (!list_empty(&gl->gl_lru)) {
list_del_init(&gl->gl_lru);