diff options
| author | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2014-05-03 11:00:29 +0200 |
|---|---|---|
| committer | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2016-02-13 00:36:20 +0100 |
| commit | 9b7ad840eb66099f5d72e3366de00973fc22d33a (patch) | |
| tree | 9d557f79ec3b5173cf732051881ed16282ae8ba7 | |
| parent | 0711a46d9caab68d689ffd30b47e8fd28086fdfa (diff) | |
| download | rt-linux-9b7ad840eb66099f5d72e3366de00973fc22d33a.tar.gz | |
blk-mq: revert raw locks, post pone notifier to POST_DEAD
The blk_mq_cpu_notify_lock should be raw because some CPU down levels
are called with interrupts off. The notifier itself calls currently one
function that is blk_mq_hctx_notify().
That function acquires the ctx->lock lock which is sleeping and I would
prefer to keep it that way. That function only moves IO-requests from
the CPU that is going offline to another CPU and it is currently the
only one. Therefore I revert the list lock back to sleeping spinlocks
and let the notifier run at POST_DEAD time.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
| -rw-r--r-- | block/blk-mq-cpu.c | 17 | ||||
| -rw-r--r-- | block/blk-mq.c | 2 |
2 files changed, 11 insertions, 8 deletions
diff --git a/block/blk-mq-cpu.c b/block/blk-mq-cpu.c index bb3ed488f7b5b..628c6c13c4823 100644 --- a/block/blk-mq-cpu.c +++ b/block/blk-mq-cpu.c @@ -16,7 +16,7 @@ #include "blk-mq.h" static LIST_HEAD(blk_mq_cpu_notify_list); -static DEFINE_RAW_SPINLOCK(blk_mq_cpu_notify_lock); +static DEFINE_SPINLOCK(blk_mq_cpu_notify_lock); static int blk_mq_main_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu) @@ -25,7 +25,10 @@ static int blk_mq_main_cpu_notify(struct notifier_block *self, struct blk_mq_cpu_notifier *notify; int ret = NOTIFY_OK; - raw_spin_lock(&blk_mq_cpu_notify_lock); + if (action != CPU_POST_DEAD) + return NOTIFY_OK; + + spin_lock(&blk_mq_cpu_notify_lock); list_for_each_entry(notify, &blk_mq_cpu_notify_list, list) { ret = notify->notify(notify->data, action, cpu); @@ -33,7 +36,7 @@ static int blk_mq_main_cpu_notify(struct notifier_block *self, break; } - raw_spin_unlock(&blk_mq_cpu_notify_lock); + spin_unlock(&blk_mq_cpu_notify_lock); return ret; } @@ -41,16 +44,16 @@ void blk_mq_register_cpu_notifier(struct blk_mq_cpu_notifier *notifier) { BUG_ON(!notifier->notify); - raw_spin_lock(&blk_mq_cpu_notify_lock); + spin_lock(&blk_mq_cpu_notify_lock); list_add_tail(¬ifier->list, &blk_mq_cpu_notify_list); - raw_spin_unlock(&blk_mq_cpu_notify_lock); + spin_unlock(&blk_mq_cpu_notify_lock); } void blk_mq_unregister_cpu_notifier(struct blk_mq_cpu_notifier *notifier) { - raw_spin_lock(&blk_mq_cpu_notify_lock); + spin_lock(&blk_mq_cpu_notify_lock); list_del(¬ifier->list); - raw_spin_unlock(&blk_mq_cpu_notify_lock); + spin_unlock(&blk_mq_cpu_notify_lock); } void blk_mq_init_cpu_notifier(struct blk_mq_cpu_notifier *notifier, diff --git a/block/blk-mq.c b/block/blk-mq.c index 798e9d8a3541a..be70458c0f3c7 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1640,7 +1640,7 @@ static int blk_mq_hctx_notify(void *data, unsigned long action, { struct blk_mq_hw_ctx *hctx = data; - if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) + if (action == CPU_POST_DEAD) return blk_mq_hctx_cpu_offline(hctx, cpu); /* |