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authorCong Zhang <cong.zhang@oss.qualcomm.com>2025-12-03 11:34:21 +0800
committerJens Axboe <axboe@kernel.dk>2025-12-04 07:19:26 -0700
commitc196bf43d706592d8801a7513603765080e495fb (patch)
tree0ffaf024c12eae960197bb852424b23768dbcfb6
parent71075d25ca5cae732fb57da065fbf14aeb3bcfc7 (diff)
blk-mq: Abort suspend when wakeup events are pending
During system suspend, wakeup capable IRQs for block device can be delayed, which can cause blk_mq_hctx_notify_offline() to hang indefinitely while waiting for pending request to complete. Skip the request waiting loop and abort suspend when wakeup events are pending to prevent the deadlock. Fixes: bf0beec0607d ("blk-mq: drain I/O when all CPUs in a hctx are offline") Signed-off-by: Cong Zhang <cong.zhang@oss.qualcomm.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
-rw-r--r--block/blk-mq.c18
1 files changed, 16 insertions, 2 deletions
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 4e96bb246247..bd8b11c472a2 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -23,6 +23,7 @@
#include <linux/cache.h>
#include <linux/sched/topology.h>
#include <linux/sched/signal.h>
+#include <linux/suspend.h>
#include <linux/delay.h>
#include <linux/crash_dump.h>
#include <linux/prefetch.h>
@@ -3718,6 +3719,7 @@ static int blk_mq_hctx_notify_offline(unsigned int cpu, struct hlist_node *node)
{
struct blk_mq_hw_ctx *hctx = hlist_entry_safe(node,
struct blk_mq_hw_ctx, cpuhp_online);
+ int ret = 0;
if (blk_mq_hctx_has_online_cpu(hctx, cpu))
return 0;
@@ -3738,12 +3740,24 @@ static int blk_mq_hctx_notify_offline(unsigned int cpu, struct hlist_node *node)
* frozen and there are no requests.
*/
if (percpu_ref_tryget(&hctx->queue->q_usage_counter)) {
- while (blk_mq_hctx_has_requests(hctx))
+ while (blk_mq_hctx_has_requests(hctx)) {
+ /*
+ * The wakeup capable IRQ handler of block device is
+ * not called during suspend. Skip the loop by checking
+ * pm_wakeup_pending to prevent the deadlock and improve
+ * suspend latency.
+ */
+ if (pm_wakeup_pending()) {
+ clear_bit(BLK_MQ_S_INACTIVE, &hctx->state);
+ ret = -EBUSY;
+ break;
+ }
msleep(5);
+ }
percpu_ref_put(&hctx->queue->q_usage_counter);
}
- return 0;
+ return ret;
}
/*