monitor: ensure we retry soon when 'remove' fails.

If a 'remove' fails there is no certainty that another event will
happen soon, so make sure we retry soon anyway.

Reported-by: Adam Kwolek <adam.kwolek@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/mdadm.h b/mdadm.h
index 3bcd0526111e878d6885b7f14bb3820964fde768..381ef8639d2444617fc75a8aa1448cbe1a8d8240 100644 (file)
--- a/mdadm.h
+++ b/mdadm.h
@@ -867,6 +867,7 @@ struct supertype {
                        *  external:/md0/12
                        */
        int devcnt;
+       int retry_soon;
 
        struct mdinfo *devs;
 

diff --git a/monitor.c b/monitor.c
index cfe41787f0f2e596502c43b181e9924c9c511eb6..c987d107c5d0ca1e29a3ad2a7e2fd81ef01ec786 100644 (file)
--- a/monitor.c
+++ b/monitor.c
@@ -212,6 +212,7 @@ static void signal_manager(void)
  */
 
 #define ARRAY_DIRTY 1
+#define ARRAY_BUSY 2
 static int read_and_act(struct active_array *a)
 {
        unsigned long long sync_completed;
@@ -419,9 +420,9 @@ static int read_and_act(struct active_array *a)
                if ((mdi->next_state & DS_REMOVE) && mdi->state_fd >= 0) {
                        int remove_result;
 
-                       /* the kernel may not be able to immediately remove the
-                        * disk, we can simply wait until the next event to try
-                        * again.
+                       /* The kernel may not be able to immediately remove the
+                        * disk.  In that case we wait a little while and
+                        * try again.
                         */
                        remove_result = write_attr("remove", mdi->state_fd);
                        if (remove_result > 0) {
@@ -429,7 +430,8 @@ static int read_and_act(struct active_array *a)
                                close(mdi->state_fd);
                                close(mdi->recovery_fd);
                                mdi->state_fd = -1;
-                       }
+                       } else
+                               ret |= ARRAY_BUSY;
                }
                if (mdi->next_state & DS_INSYNC) {
                        write_attr("+in_sync", mdi->state_fd);
@@ -597,7 +599,7 @@ static int wait_and_act(struct supertype *container, int nowait)
                struct timespec ts;
                ts.tv_sec = 24*3600;
                ts.tv_nsec = 0;
-               if (*aap == NULL) {
+               if (*aap == NULL || container->retry_soon) {
                        /* just waiting to get O_EXCL access */
                        ts.tv_sec = 0;
                        ts.tv_nsec = 20000000ULL;
@@ -612,7 +614,7 @@ static int wait_and_act(struct supertype *container, int nowait)
                #ifdef DEBUG
                dprint_wake_reasons(&rfds);
                #endif
-
+               container->retry_soon = 0;
        }
 
        if (update_queue) {
@@ -653,6 +655,8 @@ static int wait_and_act(struct supertype *container, int nowait)
                         */
                        if (sigterm && !(ret & ARRAY_DIRTY))
                                a->container = NULL; /* stop touching this array */
+                       if (ret & ARRAY_BUSY)
+                               container->retry_soon = 1;
                }
        }