Commit dff52574 authored Sep 02, 2008 by Steven Whitehouse

GFS2: Fix race relating to glock min-hold time



In the case that a request for a glock arrives right after the
grant reply has arrived, it sometimes means that the gl_tstamp
field hasn't been updated recently enough. The net result is that
the min-hold time for the glock is ignored. If this happens
often enough, it leads to poor performance.

This patch adds an additional test, so that if the reply pending
bit is set on a glock, then it will select the maximum length of
time for the min-hold time, rather than looking at gl_tstamp.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

parent 0188d6c5

fs/gfs2/glock.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -1265,6 +1265,8 @@ static void blocking_cb(struct gfs2_sbd sdp, struct lm_lockname name,
		holdtime = gl->gl_tchange + gl->gl_ops->go_min_hold_time;
		if (time_before(now, holdtime))
		delay = holdtime - now;
		if (test_bit(GLF_REPLY_PENDING, &gl->gl_flags))
		delay = gl->gl_ops->go_min_hold_time;

		spin_lock(&gl->gl_spin);
		handle_callback(gl, state, 1, delay);

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