From: Sage Weil <sage@newdream.net>
Date: Thu, 18 Mar 2010 22:20:53 +0000 (-0700)
Subject: ceph: fix connection fault con_work reentrancy problem
X-Git-Tag: firefly_0821_release~9833^2~2459^2~12
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=3c3f2e32effd4c6acc3a9434bd7eecb0af653d89;p=firefly-linux-kernel-4.4.55.git

ceph: fix connection fault con_work reentrancy problem

The messenger fault was clearing the BUSY bit, for reasons unclear.  This
made it possible for the con->ops->fault function to reopen the connection,
and requeue work in the workqueue--even though the current thread was
already in con_work.

This avoids a problem where the client busy loops with connection failures
on an unreachable OSD, but doesn't address the root cause of that problem.

Signed-off-by: Sage Weil <sage@newdream.net>
---

diff --git a/fs/ceph/messenger.c b/fs/ceph/messenger.c
index 203c4359b549..983285540945 100644
--- a/fs/ceph/messenger.c
+++ b/fs/ceph/messenger.c
@@ -1836,8 +1836,6 @@ static void ceph_fault(struct ceph_connection *con)
 		goto out;
 	}
 
-	clear_bit(BUSY, &con->state);  /* to avoid an improbable race */
-
 	mutex_lock(&con->mutex);
 	if (test_bit(CLOSED, &con->state))
 		goto out_unlock;