From: Sage Weil <sage@newdream.net>
Date: Fri, 9 Jan 2009 20:55:59 +0000 (-0800)
Subject: kclient: list unsafe requests in the MDS session
X-Git-Tag: v0.6~1^2~105
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=95fa0a12a82a00f123ef724b52d245ed92c704ac;p=ceph.git

kclient: list unsafe requests in the MDS session

This easily defines the requests needed during reconnect without having
to consult the larger request table.
---

diff --git a/src/kernel/mds_client.c b/src/kernel/mds_client.c
index 66c45f59252a2..8fc58a70a4a36 100644
--- a/src/kernel/mds_client.c
+++ b/src/kernel/mds_client.c
@@ -327,6 +327,7 @@ static struct ceph_mds_session *register_session(struct ceph_mds_client *mdsc,
 	s->s_nr_caps = 0;
 	atomic_set(&s->s_ref, 1);
 	init_completion(&s->s_completion);
+	INIT_LIST_HEAD(&s->s_unsafe);
 
 	dout(10, "register_session mds%d\n", mds);
 	if (mds >= mdsc->max_sessions) {
@@ -1292,18 +1293,18 @@ void ceph_mdsc_handle_reply(struct ceph_mds_client *mdsc, struct ceph_msg *msg)
 
 	if (req->r_got_unsafe && head->safe) {
 		/* 
-		 * We already handled the unsafe response, now
-		 * do the cleanup.  Shouldn't we check the
-		 * safe response to see if it matches the
-		 * unsafe one?
+		 * We already handled the unsafe response, now do the
+		 * cleanup.  No need to examine the response; the MDS
+		 * doesn't include any result info in the safe
+		 * response.  And even if it did, there is nothing
+		 * useful we could do with a revised return value.
 		 */
+		dout(10, "got safe reply %llu, mds%d\n", tid, mds);
+		BUG_ON(req->r_session == NULL);
 		complete(&req->r_safe_completion);
 		__unregister_request(mdsc, req);
-		dout(10, "got safe reply %llu, mds%d\n",
-		     tid, mds);
-		ceph_msg_put(req->r_request);
-		req->r_request = NULL;
 		req->r_got_safe = true;
+		list_del_init(&req->r_unsafe_item);
 		mutex_unlock(&mdsc->mutex);
 		ceph_mdsc_put_request(req);
 		return;
@@ -1324,8 +1325,10 @@ void ceph_mdsc_handle_reply(struct ceph_mds_client *mdsc, struct ceph_msg *msg)
 
 	if (head->safe)
 		req->r_got_safe = true;
-	else
+	else {
 		req->r_got_unsafe = true;
+		list_add_tail(&req->r_unsafe_item, &req->r_session->s_unsafe);
+	}
 
 	/* take the snap sem -- we may be are adding a cap here */
 	down_write(&mdsc->snap_rwsem);
diff --git a/src/kernel/mds_client.h b/src/kernel/mds_client.h
index 4334fe454bbee..0f0a644552107 100644
--- a/src/kernel/mds_client.h
+++ b/src/kernel/mds_client.h
@@ -119,6 +119,7 @@ struct ceph_mds_session {
 	int               s_nr_caps;
 	atomic_t          s_ref;
 	struct completion s_completion;
+	struct list_head  s_unsafe;   /* unsafe requests */
 };
 
 /*
@@ -174,6 +175,7 @@ struct ceph_mds_request {
 	atomic_t          r_ref;
 	struct completion r_completion;
 	struct completion r_safe_completion;
+	struct list_head  r_unsafe_item;  /* per-session unsafe list item */
 	bool		  r_got_unsafe, r_got_safe;
 };