From 265d529cef6fd57698d79b3c0edd3a8178059ea6 Mon Sep 17 00:00:00 2001 From: Steven Whitehouse Date: Mon, 7 Jul 2008 10:02:36 +0100 Subject: [GFS2] Fix delayed demote race There is a race in the delayed demote code where it does the wrong thing if a demotion to UN has occurred for other reasons before the delay has expired. This patch adds an assert to catch that condition as well as fixing the root cause by adding an additional check for the UN state. Signed-off-by: Steven Whitehouse Cc: Bob Peterson --- fs/gfs2/glock.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'fs/gfs2') diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c index 8d5450f3c3e..cd0aa213fb2 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -587,6 +587,7 @@ static void run_queue(struct gfs2_glock *gl, const int nonblock) if (nonblock) 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; } else { if (test_bit(GLF_DEMOTE, &gl->gl_flags)) @@ -617,7 +618,9 @@ static void glock_work_func(struct work_struct *work) if (test_and_clear_bit(GLF_REPLY_PENDING, &gl->gl_flags)) finish_xmote(gl, gl->gl_reply); spin_lock(&gl->gl_spin); - if (test_and_clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags)) { + if (test_and_clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && + gl->gl_state != LM_ST_UNLOCKED && + gl->gl_demote_state != LM_ST_EXCLUSIVE) { unsigned long holdtime, now = jiffies; holdtime = gl->gl_tchange + gl->gl_ops->go_min_hold_time; if (time_before(now, holdtime)) -- cgit v1.2.3