From mboxrd@z Thu Jan  1 00:00:00 1970
From: swhiteho@redhat.com <swhiteho@redhat.com>
Date: Thu,  4 Oct 2007 09:49:36 +0100
Subject: [Cluster-devel] [PATCH 43/51] [DLM] Make dlm_sendd cond_resched more
In-Reply-To: <11914878661743-git-send-email-swhiteho@redhat.com>
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From: Patrick Caulfield <pcaulfie@redhat.com>

Under high recovery loads dlm_sendd can monopolise the CPU and cause soft lockups.

This one extra and one moved cond_resched() make it yield a little more during
such times keeping work moving.

Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

diff --git a/fs/dlm/lowcomms.c b/fs/dlm/lowcomms.c
index 62a8a6c..58bf3f5 100644
--- a/fs/dlm/lowcomms.c
+++ b/fs/dlm/lowcomms.c
@@ -1264,14 +1264,15 @@ static void send_to_sock(struct connection *con)
 		if (len) {
 			ret = sendpage(con->sock, e->page, offset, len,
 				       msg_flags);
-			if (ret == -EAGAIN || ret == 0)
+			if (ret == -EAGAIN || ret == 0) {
+				cond_resched();
 				goto out;
+			}
 			if (ret <= 0)
 				goto send_error;
-		} else {
+		}
 			/* Don't starve people filling buffers */
 			cond_resched();
-		}
 
 		spin_lock(&con->writequeue_lock);
 		e->offset += ret;
-- 
1.5.1.2