From: Yehuda Sadeh <yehuda@hq.newdream.net>
Date: Thu, 23 Oct 2008 18:49:27 +0000 (-0700)
Subject: kclient: use a new reply mutex, fixes locks dependency problem
X-Git-Tag: v0.5~207
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=6fc3fcb40f6083cc8ef6295c17a494cd7c960eeb;p=ceph.git

kclient: use a new reply mutex, fixes locks dependency problem
---

diff --git a/src/kernel/mds_client.c b/src/kernel/mds_client.c
index 1355fc4adc21..6af5cfb24626 100644
--- a/src/kernel/mds_client.c
+++ b/src/kernel/mds_client.c
@@ -440,6 +440,7 @@ static struct ceph_mds_request *new_request(struct ceph_msg *msg)
 	req->r_request = msg;
 	req->r_started = jiffies;
 	req->r_resend_mds = -1;
+	mutex_init(&req->r_mutex);
 	atomic_set(&req->r_ref, 1);  /* one for request_tree, one for caller */
 	init_completion(&req->r_completion);
 	return req;
@@ -1213,8 +1214,10 @@ retry:
 		wait_for_completion(&req->r_completion);
 	}
 	mutex_lock(&mdsc->mutex);
+	mutex_lock(&req->r_mutex);
 	if (req->r_reply == NULL && !err) {
 		put_request_sessions(req);
+		mutex_unlock(&req->r_mutex);
 		goto retry;
 	}
 	if (IS_ERR(req->r_reply)) {
@@ -1225,6 +1228,7 @@ retry:
 		/* all is well, reply has been parsed. */
 		err = le32_to_cpu(req->r_reply_info.head->result);
 
+	mutex_unlock(&req->r_mutex);
 finish:
 	__unregister_request(mdsc, req);
 	mutex_unlock(&mdsc->mutex);
@@ -1349,14 +1353,14 @@ done:
 	if (took_snap_sem)
 		up_write(&mdsc->snap_rwsem);
 
-	mutex_lock(&mdsc->mutex);
+	mutex_lock(&req->r_mutex);
 	if (err) {
 		req->r_err = err;
 	} else {
 		req->r_reply = msg;
 		ceph_msg_get(msg);
 	}
-	mutex_unlock(&mdsc->mutex);
+	mutex_unlock(&req->r_mutex);
 
 	mutex_unlock(&req->r_session->s_mutex);
 
diff --git a/src/kernel/mds_client.h b/src/kernel/mds_client.h
index e5a9c4b2e563..7cb303aa29b2 100644
--- a/src/kernel/mds_client.h
+++ b/src/kernel/mds_client.h
@@ -158,6 +158,7 @@ struct ceph_mds_request {
 
 	atomic_t          r_ref;
 	struct completion r_completion;
+	struct mutex      r_mutex;
 };
 
 /*