drbd: Implemented the disk-timeout option

When the disk-timeout is active, and it expires for a single request,
we consider the local disk as D_FAILED. Note: With this change,
I made both timeout based state transitions HARD state transitions.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index bc8a8a7556da54a39a5ffc78ed588728818aeb16..4bd636524dd1f7bd41b6c69d1610bd29a057fd79 100644 (file)
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -1404,6 +1404,9 @@ static void after_state_ch(struct drbd_conf *mdev, union drbd_state os,
        /* Here we have the actions that are performed after a
           state change. This function might sleep */
 
+       if (os.disk <= D_NEGOTIATING && ns.disk > D_NEGOTIATING)
+               mod_timer(&mdev->request_timer, jiffies + HZ);
+
        nsm.i = -1;
        if (ns.susp_nod) {
                if (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED)
@@ -3318,6 +3321,8 @@ static void drbd_delete_device(unsigned int minor)
        if (!mdev)
                return;
 
+       del_timer_sync(&mdev->request_timer);
+
        /* paranoia asserts */
        if (mdev->open_cnt != 0)
                dev_err(DEV, "open_cnt = %d in %s:%u", mdev->open_cnt,

diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index e7ed0aa93a16fb1360cb19de117aefa9fd808cb7..a85bbe1bbc2b0424d81909fa8433c983457c2568 100644 (file)
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -3803,8 +3803,6 @@ static void drbd_disconnect(struct drbd_conf *mdev)
        atomic_set(&mdev->rs_pending_cnt, 0);
        wake_up(&mdev->misc_wait);
 
-       del_timer(&mdev->request_timer);
-
        /* make sure syncer is stopped and w_resume_next_sg queued */
        del_timer_sync(&mdev->resync_timer);
        resync_timer_fn((unsigned long)mdev);

diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c
index 1a8aac4b0c2fa62056ba63e46bd927898c4dbe44..ef145e33a647e496e6613a24ac8776189c57f119 100644 (file)
--- a/drivers/block/drbd/drbd_req.c
+++ b/drivers/block/drbd/drbd_req.c
@@ -1208,13 +1208,19 @@ void request_timer_fn(unsigned long data)
        struct drbd_conf *mdev = (struct drbd_conf *) data;
        struct drbd_request *req; /* oldest request */
        struct list_head *le;
-       unsigned long et = 0; /* effective timeout = ko_count * timeout */
+       unsigned long ent = 0, dt = 0, et, nt; /* effective timeout = ko_count * timeout */
 
        if (get_net_conf(mdev)) {
-               et = mdev->net_conf->timeout*HZ/10 * mdev->net_conf->ko_count;
+               ent = mdev->net_conf->timeout*HZ/10 * mdev->net_conf->ko_count;
                put_net_conf(mdev);
        }
-       if (!et || mdev->state.conn < C_WF_REPORT_PARAMS)
+       if (get_ldev(mdev)) {
+               dt = mdev->ldev->dc.disk_timeout * HZ / 10;
+               put_ldev(mdev);
+       }
+       et = min_not_zero(dt, ent);
+
+       if (!et || (mdev->state.conn < C_WF_REPORT_PARAMS && mdev->state.disk <= D_FAILED))
                return; /* Recurring timer stopped */
 
        spin_lock_irq(&mdev->req_lock);
@@ -1227,17 +1233,19 @@ void request_timer_fn(unsigned long data)
 
        le = le->prev;
        req = list_entry(le, struct drbd_request, tl_requests);
-       if (time_is_before_eq_jiffies(req->start_time + et)) {
-               if (req->rq_state & RQ_NET_PENDING) {
+       if (ent && req->rq_state & RQ_NET_PENDING) {
+               if (time_is_before_eq_jiffies(req->start_time + ent)) {
                        dev_warn(DEV, "Remote failed to finish a request within ko-count * timeout\n");
-                       _drbd_set_state(_NS(mdev, conn, C_TIMEOUT), CS_VERBOSE, NULL);
-               } else {
-                       dev_warn(DEV, "Local backing block device frozen?\n");
-                       mod_timer(&mdev->request_timer, jiffies + et);
+                       _drbd_set_state(_NS(mdev, conn, C_TIMEOUT), CS_VERBOSE | CS_HARD, NULL);
                }
-       } else {
-               mod_timer(&mdev->request_timer, req->start_time + et);
        }
-
+       if (dt && req->rq_state & RQ_LOCAL_PENDING) {
+               if (time_is_before_eq_jiffies(req->start_time + dt)) {
+                       dev_warn(DEV, "Local backing device failed to meet the disk-timeout\n");
+                       __drbd_chk_io_error(mdev, 1);
+               }
+       }
+       nt = (time_is_before_eq_jiffies(req->start_time + et) ? jiffies : req->start_time) + et;
        spin_unlock_irq(&mdev->req_lock);
+       mod_timer(&mdev->request_timer, nt);
 }

diff --git a/include/linux/drbd_limits.h b/include/linux/drbd_limits.h
index 928c84dfaf42aacb31a2f0a93cc701f04cc8fba3..fb670bf603f7c730469d0c56c22abb7f6274d192 100644 (file)
--- a/include/linux/drbd_limits.h
+++ b/include/linux/drbd_limits.h
@@ -48,6 +48,11 @@
 #define DRBD_TIMEOUT_MAX 600
 #define DRBD_TIMEOUT_DEF 60       /* 6 seconds */
 
+ /* If backing disk takes longer than disk_timeout, mark the disk as failed */
+#define DRBD_DISK_TIMEOUT_MIN 0    /* 0 = disabled */
+#define DRBD_DISK_TIMEOUT_MAX 6000 /* 10 Minutes */
+#define DRBD_DISK_TIMEOUT_DEF 0    /* disabled */
+
   /* active connection retries when C_WF_CONNECTION */
 #define DRBD_CONNECT_INT_MIN 1
 #define DRBD_CONNECT_INT_MAX 120

diff --git a/include/linux/drbd_nl.h b/include/linux/drbd_nl.h
index 7203c9ead23385c95aabc31dd9bdb28e60986d52..a8706f08ab367cfb9b8b9ac79b7f62cb94d0a876 100644 (file)
--- a/include/linux/drbd_nl.h
+++ b/include/linux/drbd_nl.h
@@ -31,6 +31,7 @@ NL_PACKET(disk_conf, 3,
        NL_INTEGER(     56,     T_MAY_IGNORE,   max_bio_bvecs)
        NL_BIT(         57,     T_MAY_IGNORE,   no_disk_barrier)
        NL_BIT(         58,     T_MAY_IGNORE,   no_disk_drain)
+       NL_INTEGER(     89,     T_MAY_IGNORE,   disk_timeout)
 )
 
 NL_PACKET(detach, 4,