From: Bob Peterson rpeterso@redhat.com
[ Upstream commit b14c94908b1b884276a6608dea3d0b1b510338b7 ]
This reverts commit df5db5f9ee112e76b5202fbc331f990a0fc316d6.
This patch fixes a regression: patch df5db5f9ee112 allowed function run_queue() to bypass its call to do_xmote() if revokes were queued for the glock. That's wrong because its call to do_xmote() is what is responsible for calling the go_sync() glops functions to sync both the ail list and any revokes queued for it. By bypassing the call, gfs2 could get into a stand-off where the glock could not be demoted until its revokes are written back, but the revokes would not be written back because do_xmote() was never called.
It "sort of" works, however, because there are other mechanisms like the log flush daemon (logd) that can sync the ail items and revokes, if it deems it necessary. The problem is: without file system pressure, it might never deem it necessary.
Signed-off-by: Bob Peterson rpeterso@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/gfs2/glock.c | 3 --- 1 file changed, 3 deletions(-)
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c index adc1a97cfe96..efd44d5645d8 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -548,9 +548,6 @@ __acquires(&gl->gl_lockref.lock) goto out_unlock; if (nonblock) goto out_sched; - smp_mb(); - if (atomic_read(&gl->gl_revokes) != 0) - goto out_sched; set_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags); GLOCK_BUG_ON(gl, gl->gl_demote_state == LM_ST_EXCLUSIVE); gl->gl_target = gl->gl_demote_state;