path: root/fs/dlm/lock.c
diff options
authorSteven Whitehouse <swhiteho@redhat.com>2010-09-03 10:07:48 -0500
committerDavid Teigland <teigland@redhat.com>2010-09-03 10:10:47 -0500
commit314dd2a05340fffbe217c5e40ec6c3bd1d07bf89 (patch)
treec4e5cf876ed951e47e7fad8bef0c69ea5df0c7dd /fs/dlm/lock.c
parent2bfc96a127bc1cc94d26bfaa40159966064f9c8c (diff)
dlm: Don't send callback to node making lock request when "try 1cb" fails
When converting a lock, an lkb is in the granted state and also being used to request a new state. In the case that the conversion was a "try 1cb" type which has failed, and if the new state was incompatible with the old state, a callback was being generated to the requesting node. This is incorrect as callbacks should only be sent to all the other nodes holding blocking locks. The requesting node should receive the normal (failed) response to its "try 1cb" conversion request only. This was discovered while debugging a performance problem on GFS2, however this fix also speeds up GFS as well. In the GFS2 case the performance gain is over 10x for cases of write activity to an inode whose glock is cached on another, idle (wrt that glock) node. (comment added, dct) Signed-off-by: Steven Whitehouse <swhiteho@redhat.com> Tested-by: Abhijith Das <adas@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
Diffstat (limited to 'fs/dlm/lock.c')
1 files changed, 3 insertions, 0 deletions
diff --git a/fs/dlm/lock.c b/fs/dlm/lock.c
index 031dbe3a15ca..64e5f3efdd81 100644
--- a/fs/dlm/lock.c
+++ b/fs/dlm/lock.c
@@ -1846,6 +1846,9 @@ static void send_bast_queue(struct dlm_rsb *r, struct list_head *head,
struct dlm_lkb *gr;
list_for_each_entry(gr, head, lkb_statequeue) {
+ /* skip self when sending basts to convertqueue */
+ if (gr == lkb)
+ continue;
if (gr->lkb_bastfn && modes_require_bast(gr, lkb)) {
queue_bast(r, gr, lkb->lkb_rqmode);
gr->lkb_highbast = lkb->lkb_rqmode;