From: Andriy Skulysh <c17819@cray.com>
Date: Wed, 24 Nov 2021 11:33:47 +0000 (+0200)
Subject: LU-15402 ldlm: speedup RD flock enqueue
X-Git-Url: https://git.whamcloud.com/gitweb?a=commitdiff_plain;h=9a7e790be094e07184ce3d2e3794222252a05914;p=fs%2Flustre-release.git

LU-15402 ldlm: speedup RD flock enqueue

Scanning of lr_granted can be done until
covering granted RD lock is reached.

Lustre-change: https://review.whamcloud.com/45957
Lustre-commit: b07a57027ee5cc1afa82cc4c82be73a2c4894502

Change-Id: I907cff002d9765c5f8496d377eddd5e62795d89c
HPE-bug-id: LUS-10623
Signed-off-by: Andriy Skulysh <c17819@cray.com>
Reviewed-on: https://review.whamcloud.com/48323
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
---

diff --git a/lustre/ldlm/ldlm_flock.c b/lustre/ldlm/ldlm_flock.c
index d5f740f..1941872 100644
--- a/lustre/ldlm/ldlm_flock.c
+++ b/lustre/ldlm/ldlm_flock.c
@@ -356,6 +356,15 @@ reprocess:
 				continue;
 			}
 
+			if (req->l_req_mode == LCK_PR &&
+			    lock->l_granted_mode == LCK_PR &&
+			    lock->l_policy_data.l_flock.start <=
+				req->l_policy_data.l_flock.start &&
+			    lock->l_policy_data.l_flock.end >=
+				req->l_policy_data.l_flock.end) {
+				/* there can't be granted WR lock */
+				break;
+			}
 			/* locks are compatible, overlap doesn't matter */
 			if (lockmode_compat(lock->l_granted_mode, mode))
 				continue;