From aa8dcccaf32bfdc09f2aff089d5d60c37da5b7b5 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 27 Jan 2022 08:05:49 +0100 Subject: [PATCH] block: check that there is a plug in blk_flush_plug Rename blk_flush_plug to __blk_flush_plug and add a wrapper that includes the NULL check instead of open coding that check everywhere. Signed-off-by: Christoph Hellwig Reviewed-by: Chaitanya Kulkarni Link: https://lore.kernel.org/r/20220127070549.1377856-2-hch@lst.de Signed-off-by: Jens Axboe --- block/blk-core.c | 7 +++---- fs/fs-writeback.c | 6 ++---- include/linux/blkdev.h | 7 ++++++- kernel/sched/core.c | 7 ++----- 4 files changed, 13 insertions(+), 14 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index d93e3bb9a769..61f6a0dc4511 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -991,8 +991,7 @@ int bio_poll(struct bio *bio, struct io_comp_batch *iob, unsigned int flags) !test_bit(QUEUE_FLAG_POLL, &q->queue_flags)) return 0; - if (current->plug) - blk_flush_plug(current->plug, false); + blk_flush_plug(current->plug, false); if (blk_queue_enter(q, BLK_MQ_REQ_NOWAIT)) return 0; @@ -1274,7 +1273,7 @@ struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug, void *data, } EXPORT_SYMBOL(blk_check_plugged); -void blk_flush_plug(struct blk_plug *plug, bool from_schedule) +void __blk_flush_plug(struct blk_plug *plug, bool from_schedule) { if (!list_empty(&plug->cb_list)) flush_plug_callbacks(plug, from_schedule); @@ -1303,7 +1302,7 @@ void blk_flush_plug(struct blk_plug *plug, bool from_schedule) void blk_finish_plug(struct blk_plug *plug) { if (plug == current->plug) { - blk_flush_plug(plug, false); + __blk_flush_plug(plug, false); current->plug = NULL; } } diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index f4ce38f6fc31..33d54c9fbefc 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -1903,8 +1903,7 @@ static long writeback_sb_inodes(struct super_block *sb, * unplug, so get our IOs out the door before we * give up the CPU. */ - if (current->plug) - blk_flush_plug(current->plug, false); + blk_flush_plug(current->plug, false); cond_resched(); } @@ -2301,8 +2300,7 @@ void wakeup_flusher_threads(enum wb_reason reason) /* * If we are expecting writeback progress we must submit plugged IO. */ - if (current->plug) - blk_flush_plug(current->plug, true); + blk_flush_plug(current->plug, true); rcu_read_lock(); list_for_each_entry_rcu(bdi, &bdi_list, bdi_list) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index f902a1c2fac0..654163d3b903 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1053,7 +1053,12 @@ extern void blk_start_plug(struct blk_plug *); extern void blk_start_plug_nr_ios(struct blk_plug *, unsigned short); extern void blk_finish_plug(struct blk_plug *); -void blk_flush_plug(struct blk_plug *plug, bool from_schedule); +void __blk_flush_plug(struct blk_plug *plug, bool from_schedule); +static inline void blk_flush_plug(struct blk_plug *plug, bool async) +{ + if (plug) + __blk_flush_plug(plug, async); +} int blkdev_issue_flush(struct block_device *bdev); long nr_blockdev_pages(void); diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 3487bb92d1f2..46152982e400 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6344,8 +6344,7 @@ static inline void sched_submit_work(struct task_struct *tsk) * If we are going to sleep and we have plugged IO queued, * make sure to submit it to avoid deadlocks. */ - if (tsk->plug) - blk_flush_plug(tsk->plug, true); + blk_flush_plug(tsk->plug, true); } static void sched_update_worker(struct task_struct *tsk) @@ -8371,9 +8370,7 @@ int io_schedule_prepare(void) int old_iowait = current->in_iowait; current->in_iowait = 1; - if (current->plug) - blk_flush_plug(current->plug, true); - + blk_flush_plug(current->plug, true); return old_iowait; }