[PATCH 1/6] drivers/md/raid5: Use irqsave variant of atomic_dec_and_lock()

From: Sebastian Andrzej Siewior
Date: Tue Jul 03 2018 - 16:05:08 EST


From: Anna-Maria Gleixner <anna-maria@xxxxxxxxxxxxx>

The irqsave variant of atomic_dec_and_lock handles irqsave/restore when
taking/releasing the spin lock. With this variant the call of
local_irq_save is no longer required.

Cc: Shaohua Li <shli@xxxxxxxxxx>
Cc: linux-raid@xxxxxxxxxxxxxxx
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Anna-Maria Gleixner <anna-maria@xxxxxxxxxxxxx>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
---
drivers/md/raid5.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 2031506a0ecd..e933bff9459e 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -409,16 +409,15 @@ void raid5_release_stripe(struct stripe_head *sh)
md_wakeup_thread(conf->mddev->thread);
return;
slow_path:
- local_irq_save(flags);
/* we are ok here if STRIPE_ON_RELEASE_LIST is set or not */
- if (atomic_dec_and_lock(&sh->count, &conf->device_lock)) {
+ if (atomic_dec_and_lock_irqsave(&sh->count, &conf->device_lock, flags)) {
INIT_LIST_HEAD(&list);
hash = sh->hash_lock_index;
do_release_stripe(conf, sh, &list);
spin_unlock(&conf->device_lock);
release_inactive_stripe_list(conf, &list, hash);
+ local_irq_restore(flags);
}
- local_irq_restore(flags);
}

static inline void remove_hash(struct stripe_head *sh)
--
2.18.0