LU-11296 osc: speed up page cache cleanup during blocking ASTs

While we are cleaning a write lock, we don't need to check if
page cache pages under this lock are covered by another lock.

If a client needs to give up its lock, cleaning gigabytes of
page cache can take quite a long time.

Lustre-change: https://review.whamcloud.com/33090
Lustre-commit: b9ebb17277c78101018a0cf4a63f6beb93b9baf0

Signed-off-by: Andrew Perepechko <c17827@cray.com>
Cray-bug-id: LUS-6352
Change-Id: I576130216ed4de4e352ea697bddb5ff83046443a
Reviewed-by: Patrick Farrell <paf@cray.com>
Reviewed-by: Alexander Zarochentsev <c17826@cray.com>
Reviewed-by: Jinshan Xiong <jinshan.xiong@gmail.com>
Signed-off-by: Minh Diep <mdiep@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/35831
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>

diff --git a/lustre/osc/osc_lock.c b/lustre/osc/osc_lock.c
index 23fa3fa..aaadaab 100644 (file)
--- a/lustre/osc/osc_lock.c
+++ b/lustre/osc/osc_lock.c
@@ -377,7 +377,12 @@ static int osc_lock_flush(struct osc_object *obj, pgoff_t start, pgoff_t end,
                        rc = 0;
        }
 
-       rc2 = osc_lock_discard_pages(env, obj, start, end, discard);
+       /*
+        * Do not try to match other locks with CLM_WRITE since we already
+        * know there're none
+        */
+       rc2 = osc_lock_discard_pages(env, obj, start, end,
+                                    mode == CLM_WRITE || discard);
        if (rc == 0 && rc2 < 0)
                rc = rc2;