AcoSail/kernel_optimize_test
8
0
Fork 0
forked from luck/tmp_suning_uos_patched
Code Pull Requests Activity

GFS2: Only wait for demote when last holder is dequeued

Browse Source 
Function gfs2_glock_dq_wait is supposed to dequeue a glock and then
wait for the lock to be demoted. The problem is, if this is a shared
lock, its demote will depend on the other holders, which means you
might end up waiting forever because the other process is blocked.
This problem is especially apparent when dealing with nested flocks.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This commit is contained in:
Bob Peterson 2014-06-20 09:36:41 -04:00 committed by Steven Whitehouse
parent 3c8fb50445
commit 79272b3562
1 changed files with 3 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
fs/gfs2/glock.c
View File

@ -1128,7 +1128,9 @@ void gfs2_glock_dq_wait(struct gfs2_holder *gh)
struct gfs2_glock *gl = gh->gh_gl;
gfs2_glock_dq(gh);
might_sleep();
wait_on_bit(&gl->gl_flags, GLF_DEMOTE, gfs2_glock_demote_wait, TASK_UNINTERRUPTIBLE);
if (!find_first_holder(gl))
wait_on_bit(&gl->gl_flags, GLF_DEMOTE, gfs2_glock_demote_wait,
TASK_UNINTERRUPTIBLE);
}
/**