GFS2: Eliminate redundant calls to may_grant

Function add_to_queue was checking may_grant for the passed-in
holder for every iteration of its gh2 loop. Now it only checks it
once at the beginning to see if a try lock is futile.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This commit is contained in:
Bob Peterson 2012-08-09 12:48:46 -05:00 committed by Steven Whitehouse
parent 81e1d45061
commit e5dc76b9af

View file

@ -954,7 +954,7 @@ __acquires(&gl->gl_spin)
struct gfs2_sbd *sdp = gl->gl_sbd;
struct list_head *insert_pt = NULL;
struct gfs2_holder *gh2;
int try_lock = 0;
int try_futile = 0;
BUG_ON(gh->gh_owner_pid == NULL);
if (test_and_set_bit(HIF_WAIT, &gh->gh_iflags))
@ -962,7 +962,7 @@ __acquires(&gl->gl_spin)
if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) {
if (test_bit(GLF_LOCK, &gl->gl_flags))
try_lock = 1;
try_futile = !may_grant(gl, gh);
if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags))
goto fail;
}
@ -971,9 +971,8 @@ __acquires(&gl->gl_spin)
if (unlikely(gh2->gh_owner_pid == gh->gh_owner_pid &&
(gh->gh_gl->gl_ops->go_type != LM_TYPE_FLOCK)))
goto trap_recursive;
if (try_lock &&
!(gh2->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) &&
!may_grant(gl, gh)) {
if (try_futile &&
!(gh2->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) {
fail:
gh->gh_error = GLR_TRYFAILED;
gfs2_holder_wake(gh);