aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorAlex Elder <elder@inktank.com>2013-04-01 16:12:14 -0500
committerSage Weil <sage@inktank.com>2013-05-01 21:17:54 -0700
commitace6d3a96f00c271b3f337adcde8e8cbe39c3820 (patch)
treecb93ac34e892b61ee9303e051384bb64ed925caa
parent25d71cb92d8eb48df9cbd8cc4bb28e88ee8e88d9 (diff)
libceph: drop ceph_osd_request->r_con_filling_msg
A field in an osd request keeps track of whether a connection is currently filling the request's reply message. This patch gets rid of that field. An osd request includes two messages--a request and a reply--and they're both associated with the connection that existed to its the target osd at the time the request was created. An osd request can be dropped early, even when it's in flight. And at that time both messages are released. It's possible the reply message has been supplied to its connection to receive an incoming response message at the time the osd request gets dropped. So ceph_osdc_release_request() revokes that message from the connection before releasing it so things get cleaned up properly. Previously this may have caused a problem, because the connection that a message was associated with might have gone away before the revoke request. And to avoid any problems using that connection, the osd client held a reference to it when it supplies its response message. However since this commit: 38941f80 libceph: have messages point to their connection all messages hold a reference to the connection they are associated with whenever the connection is actively operating on the message (i.e. while the message is queued to send or sending, and when it data is being received into it). And if a message has no connection associated with it, ceph_msg_revoke_incoming() won't do anything when asked to revoke it. As a result, there is no need to keep an additional reference to the connection associated with a message when we hand the message to the messenger when it calls our alloc_msg() method to receive something. If the connection *were* operating on it, it would have its own reference, and if not, there's no work to be done when we need to revoke it. So get rid of the osd request's r_con_filling_msg field. This resolves: http://tracker.ceph.com/issues/4647 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
-rw-r--r--include/linux/ceph/osd_client.h2
-rw-r--r--net/ceph/osd_client.c29
2 files changed, 5 insertions, 26 deletions
diff --git a/include/linux/ceph/osd_client.h b/include/linux/ceph/osd_client.h
index 5fd2cbfcfd91..3b5ba31c2cbd 100644
--- a/include/linux/ceph/osd_client.h
+++ b/include/linux/ceph/osd_client.h
@@ -89,8 +89,6 @@ struct ceph_osd_request {
int r_pg_osds[CEPH_PG_MAX_SIZE];
int r_num_pg_osds;
- struct ceph_connection *r_con_filling_msg;
-
struct ceph_msg *r_request, *r_reply;
int r_flags; /* any additional flags for the osd */
u32 r_sent; /* >0 if r_request is sending/sent */
diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index ca79cad50840..e0887923e5ab 100644
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -91,15 +91,10 @@ void ceph_osdc_release_request(struct kref *kref)
if (req->r_request)
ceph_msg_put(req->r_request);
- if (req->r_con_filling_msg) {
- dout("%s revoking msg %p from con %p\n", __func__,
- req->r_reply, req->r_con_filling_msg);
+ if (req->r_reply) {
ceph_msg_revoke_incoming(req->r_reply);
- req->r_con_filling_msg->ops->put(req->r_con_filling_msg);
- req->r_con_filling_msg = NULL;
- }
- if (req->r_reply)
ceph_msg_put(req->r_reply);
+ }
if (req->r_data_in.type == CEPH_OSD_DATA_TYPE_PAGES &&
req->r_data_in.own_pages) {
@@ -1353,16 +1348,6 @@ static void handle_reply(struct ceph_osd_client *osdc, struct ceph_msg *msg,
for (i = 0; i < numops; i++)
req->r_reply_op_result[i] = ceph_decode_32(&p);
- /*
- * if this connection filled our message, drop our reference now, to
- * avoid a (safe but slower) revoke later.
- */
- if (req->r_con_filling_msg == con && req->r_reply == msg) {
- dout(" dropping con_filling_msg ref %p\n", con);
- req->r_con_filling_msg = NULL;
- con->ops->put(con);
- }
-
if (!req->r_got_reply) {
unsigned int bytes;
@@ -2199,13 +2184,10 @@ static struct ceph_msg *get_reply(struct ceph_connection *con,
goto out;
}
- if (req->r_con_filling_msg) {
+ if (req->r_reply->con)
dout("%s revoking msg %p from old con %p\n", __func__,
- req->r_reply, req->r_con_filling_msg);
- ceph_msg_revoke_incoming(req->r_reply);
- req->r_con_filling_msg->ops->put(req->r_con_filling_msg);
- req->r_con_filling_msg = NULL;
- }
+ req->r_reply, req->r_reply->con);
+ ceph_msg_revoke_incoming(req->r_reply);
if (front > req->r_reply->front.iov_len) {
pr_warning("get_reply front %d > preallocated %d\n",
@@ -2236,7 +2218,6 @@ static struct ceph_msg *get_reply(struct ceph_connection *con,
}
}
*skip = 0;
- req->r_con_filling_msg = con->ops->get(con);
dout("get_reply tid %lld %p\n", tid, m);
out:

Privacy Policy