Grow: allow monitor thread to exit when there is nothing more to do.

When an array using native metadata is increasing in size, we don't
need to keep monitoring it after the initial 'critical section'.
So detect that case.
If a final level-change is still needed mdadm will wait for that,
otherwise it will simply exit.

Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/Grow.c b/Grow.c
index c11b1cee96324f879642256357700e028b0d434e..9b4d5fbdcecb7981c1acc53eae2dc2f8460b6f19 100644 (file)
--- a/Grow.c
+++ b/Grow.c
@@ -3016,6 +3016,11 @@ int child_monitor(int afd, struct mdinfo *sra, struct reshape *reshape,
                                done = 1;
                        break;
                }
+               if (rv == 0 && increasing && !st->ss->external) {
+                       /* No longer need to monitor this reshape */
+                       done = 1;
+                       break;
+               }
 
                while (rv) {
                        unsigned long long offset;