ceph: reset osd after relevant messages timed out
This simplifies the process of timing out messages. We
keep lru of current messages that are in flight. If a
timeout has passed, we reset the osd connection, so that
messages will be retransmitted. This is a failsafe in case
we hit some sort of problem sending out message to the OSD.
Normally, we'll get notification via an updated osdmap if
there are problems.
If a request is older than the keepalive timeout, send a
keepalive to ensure we detect any breaks in the TCP connection.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
diff --git a/fs/ceph/osd_client.c b/fs/ceph/osd_client.c
index c4763bf..dbe63db9 100644
--- a/fs/ceph/osd_client.c
+++ b/fs/ceph/osd_client.c
@@ -17,6 +17,8 @@
#define OSD_OPREPLY_FRONT_LEN 512
const static struct ceph_connection_operations osd_con_ops;
+static int __kick_requests(struct ceph_osd_client *osdc,
+ struct ceph_osd *kickosd);
static void kick_requests(struct ceph_osd_client *osdc, struct ceph_osd *osd);
@@ -339,6 +341,7 @@
osd->o_con.ops = &osd_con_ops;
osd->o_con.peer_name.type = CEPH_ENTITY_TYPE_OSD;
+ INIT_LIST_HEAD(&osd->o_keepalive_item);
return osd;
}
@@ -461,6 +464,16 @@
return NULL;
}
+static void __schedule_osd_timeout(struct ceph_osd_client *osdc)
+{
+ schedule_delayed_work(&osdc->timeout_work,
+ osdc->client->mount_args->osd_keepalive_timeout * HZ);
+}
+
+static void __cancel_osd_timeout(struct ceph_osd_client *osdc)
+{
+ cancel_delayed_work(&osdc->timeout_work);
+}
/*
* Register request, assign tid. If this is the first request, set up
@@ -472,21 +485,16 @@
mutex_lock(&osdc->request_mutex);
req->r_tid = ++osdc->last_tid;
req->r_request->hdr.tid = cpu_to_le64(req->r_tid);
+ INIT_LIST_HEAD(&req->r_req_lru_item);
dout("register_request %p tid %lld\n", req, req->r_tid);
__insert_request(osdc, req);
ceph_osdc_get_request(req);
osdc->num_requests++;
- req->r_timeout_stamp =
- jiffies + osdc->client->mount_args->osd_timeout*HZ;
-
if (osdc->num_requests == 1) {
- osdc->timeout_tid = req->r_tid;
- dout(" timeout on tid %llu at %lu\n", req->r_tid,
- req->r_timeout_stamp);
- schedule_delayed_work(&osdc->timeout_work,
- round_jiffies_relative(req->r_timeout_stamp - jiffies));
+ dout(" first request, scheduling timeout\n");
+ __schedule_osd_timeout(osdc);
}
mutex_unlock(&osdc->request_mutex);
}
@@ -513,21 +521,10 @@
ceph_osdc_put_request(req);
- if (req->r_tid == osdc->timeout_tid) {
- if (osdc->num_requests == 0) {
- dout("no requests, canceling timeout\n");
- osdc->timeout_tid = 0;
- cancel_delayed_work(&osdc->timeout_work);
- } else {
- req = rb_entry(rb_first(&osdc->requests),
- struct ceph_osd_request, r_node);
- osdc->timeout_tid = req->r_tid;
- dout("rescheduled timeout on tid %llu at %lu\n",
- req->r_tid, req->r_timeout_stamp);
- schedule_delayed_work(&osdc->timeout_work,
- round_jiffies_relative(req->r_timeout_stamp -
- jiffies));
- }
+ list_del_init(&req->r_req_lru_item);
+ if (osdc->num_requests == 0) {
+ dout(" no requests, canceling timeout\n");
+ __cancel_osd_timeout(osdc);
}
}
@@ -540,6 +537,7 @@
ceph_con_revoke(&req->r_osd->o_con, req->r_request);
req->r_sent = 0;
}
+ list_del_init(&req->r_req_lru_item);
}
/*
@@ -635,7 +633,8 @@
reqhead->flags |= cpu_to_le32(req->r_flags); /* e.g., RETRY */
reqhead->reassert_version = req->r_reassert_version;
- req->r_timeout_stamp = jiffies+osdc->client->mount_args->osd_timeout*HZ;
+ req->r_sent_stamp = jiffies;
+ list_move_tail(&osdc->req_lru, &req->r_req_lru_item);
ceph_msg_get(req->r_request); /* send consumes a ref */
ceph_con_send(&req->r_osd->o_con, req->r_request);
@@ -656,11 +655,14 @@
{
struct ceph_osd_client *osdc =
container_of(work, struct ceph_osd_client, timeout_work.work);
- struct ceph_osd_request *req;
+ struct ceph_osd_request *req, *last_req = NULL;
struct ceph_osd *osd;
unsigned long timeout = osdc->client->mount_args->osd_timeout * HZ;
- unsigned long next_timeout = timeout + jiffies;
+ unsigned long keepalive =
+ osdc->client->mount_args->osd_keepalive_timeout * HZ;
+ unsigned long last_sent = 0;
struct rb_node *p;
+ struct list_head slow_osds;
dout("timeout\n");
down_read(&osdc->map_sem);
@@ -683,25 +685,56 @@
continue;
}
}
- for (p = rb_first(&osdc->osds); p; p = rb_next(p)) {
- osd = rb_entry(p, struct ceph_osd, o_node);
- if (list_empty(&osd->o_requests))
- continue;
- req = list_first_entry(&osd->o_requests,
- struct ceph_osd_request, r_osd_item);
- if (time_before(jiffies, req->r_timeout_stamp))
- continue;
- dout(" tid %llu (at least) timed out on osd%d\n",
+ /*
+ * reset osds that appear to be _really_ unresponsive. this
+ * is a failsafe measure.. we really shouldn't be getting to
+ * this point if the system is working properly. the monitors
+ * should mark the osd as failed and we should find out about
+ * it from an updated osd map.
+ */
+ while (!list_empty(&osdc->req_lru)) {
+ req = list_entry(osdc->req_lru.next, struct ceph_osd_request,
+ r_req_lru_item);
+
+ if (time_before(jiffies, req->r_sent_stamp + timeout))
+ break;
+
+ BUG_ON(req == last_req && req->r_sent_stamp == last_sent);
+ last_req = req;
+ last_sent = req->r_sent_stamp;
+
+ osd = req->r_osd;
+ BUG_ON(!osd);
+ pr_warning(" tid %llu timed out on osd%d, will reset osd\n",
+ req->r_tid, osd->o_osd);
+ __kick_requests(osdc, osd);
+ }
+
+ /*
+ * ping osds that are a bit slow. this ensures that if there
+ * is a break in the TCP connection we will notice, and reopen
+ * a connection with that osd (from the fault callback).
+ */
+ INIT_LIST_HEAD(&slow_osds);
+ list_for_each_entry(req, &osdc->req_lru, r_req_lru_item) {
+ if (time_before(jiffies, req->r_sent_stamp + keepalive))
+ break;
+
+ osd = req->r_osd;
+ BUG_ON(!osd);
+ dout(" tid %llu is slow, will send keepalive on osd%d\n",
req->r_tid, osd->o_osd);
- req->r_timeout_stamp = next_timeout;
+ list_move_tail(&osd->o_keepalive_item, &slow_osds);
+ }
+ while (!list_empty(&slow_osds)) {
+ osd = list_entry(slow_osds.next, struct ceph_osd,
+ o_keepalive_item);
+ list_del_init(&osd->o_keepalive_item);
ceph_con_keepalive(&osd->o_con);
}
- if (osdc->timeout_tid)
- schedule_delayed_work(&osdc->timeout_work,
- round_jiffies_relative(timeout));
-
+ __schedule_osd_timeout(osdc);
mutex_unlock(&osdc->request_mutex);
up_read(&osdc->map_sem);
@@ -819,18 +852,7 @@
}
-/*
- * Resubmit osd requests whose osd or osd address has changed. Request
- * a new osd map if osds are down, or we are otherwise unable to determine
- * how to direct a request.
- *
- * Close connections to down osds.
- *
- * If @who is specified, resubmit requests for that specific osd.
- *
- * Caller should hold map_sem for read and request_mutex.
- */
-static void kick_requests(struct ceph_osd_client *osdc,
+static int __kick_requests(struct ceph_osd_client *osdc,
struct ceph_osd *kickosd)
{
struct ceph_osd_request *req;
@@ -839,7 +861,6 @@
int err;
dout("kick_requests osd%d\n", kickosd ? kickosd->o_osd : -1);
- mutex_lock(&osdc->request_mutex);
if (kickosd) {
__reset_osd(osdc, kickosd);
} else {
@@ -900,14 +921,36 @@
req->r_resend = true;
}
}
+
+ return needmap;
+}
+
+/*
+ * Resubmit osd requests whose osd or osd address has changed. Request
+ * a new osd map if osds are down, or we are otherwise unable to determine
+ * how to direct a request.
+ *
+ * Close connections to down osds.
+ *
+ * If @who is specified, resubmit requests for that specific osd.
+ *
+ * Caller should hold map_sem for read and request_mutex.
+ */
+static void kick_requests(struct ceph_osd_client *osdc,
+ struct ceph_osd *kickosd)
+{
+ int needmap;
+
+ mutex_lock(&osdc->request_mutex);
+ needmap = __kick_requests(osdc, kickosd);
mutex_unlock(&osdc->request_mutex);
if (needmap) {
dout("%d requests for down osds, need new map\n", needmap);
ceph_monc_request_next_osdmap(&osdc->client->monc);
}
-}
+}
/*
* Process updated osd map.
*
@@ -1164,11 +1207,11 @@
init_completion(&osdc->map_waiters);
osdc->last_requested_map = 0;
mutex_init(&osdc->request_mutex);
- osdc->timeout_tid = 0;
osdc->last_tid = 0;
osdc->osds = RB_ROOT;
INIT_LIST_HEAD(&osdc->osd_lru);
osdc->requests = RB_ROOT;
+ INIT_LIST_HEAD(&osdc->req_lru);
osdc->num_requests = 0;
INIT_DELAYED_WORK(&osdc->timeout_work, handle_timeout);
INIT_DELAYED_WORK(&osdc->osds_timeout_work, handle_osds_timeout);