md: use TASK_IDLE instead of blocking signals

Hi - I submit this patch for the next merge window:

Some times ago, I made a patch f9c79bc05a2a that blocks signals around the
schedule() calls in MD. The MD subsystem needs to do an uninterruptible
sleep that is not accounted in load average - so we block signals and use
interruptible sleep.

The kernel has a special TASK_IDLE state for this purpose, so we can use
it instead of blocking signals. This patch doesn't fix any bug, it just
makes the code simpler.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Acked-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>

1 files changed, 1 insertions, 6 deletions

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 9428dfa7e9a0..1f36473c79dc 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -37,7 +37,6 @@
 #include <linux/module.h>
 #include <linux/seq_file.h>
 #include <linux/ratelimit.h>
-#include <linux/sched/signal.h>
 
 #include <trace/events/block.h>
 
@@ -1320,18 +1319,14 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio,
                  */
                 DEFINE_WAIT(w);
                 for (;;) {
-                        sigset_t full, old;
                         prepare_to_wait(&conf->wait_barrier,
-                                        &w, TASK_INTERRUPTIBLE);
+                                        &w, TASK_IDLE);
                         if (!mddev_is_clustered(mddev) ||
                             !md_cluster_ops->area_resyncing(mddev, WRITE,
                                                         bio->bi_iter.bi_sector,
                                                         bio_end_sector(bio)))
                                 break;
-                        sigfillset(&full);
-                        sigprocmask(SIG_BLOCK, &full, &old);
                         schedule();
-                        sigprocmask(SIG_SETMASK, &old, NULL);
                 }
                 finish_wait(&conf->wait_barrier, &w);
         }