From 5ebeb16ea606f6d740606b2beff0613fb34fae31 Mon Sep 17 00:00:00 2001 From: Bob Peterson Date: Thu, 9 Aug 2012 12:48:46 -0500 Subject: [PATCH] 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 Signed-off-by: Steven Whitehouse --- fs/gfs2/glock.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c index fca6a873dcf3..e6c2fd53cab2 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -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); -- 2.39.5