From ccadc8a21ef13eb80006ecff6a7466810e4f0dd6 Mon Sep 17 00:00:00 2001 From: Mikulas Patocka Date: Fri, 17 Nov 2023 18:24:04 +0100 Subject: [PATCH] dm-delay: avoid duplicate logic This is small refactoring of dm-delay - we avoid duplicate logic in flush_delayed_bios and flush_delayed_bios_fast and join these two functions into one. We also add cond_resched() to flush_delayed_bios because the list may have unbounded number of entries. Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer --- drivers/md/dm-delay.c | 65 ++++++++++++++----------------------------- 1 file changed, 21 insertions(+), 44 deletions(-) diff --git a/drivers/md/dm-delay.c b/drivers/md/dm-delay.c index 00c09d9fffeb..5eabdb06c649 100644 --- a/drivers/md/dm-delay.c +++ b/drivers/md/dm-delay.c @@ -85,24 +85,40 @@ static void flush_bios(struct bio *bio) } } -static void flush_delayed_bios_fast(struct delay_c *dc, bool flush_all) +static void flush_delayed_bios(struct delay_c *dc, bool flush_all) { struct dm_delay_info *delayed, *next; struct bio_list flush_bio_list; + unsigned long next_expires = 0; + bool start_timer = false; bio_list_init(&flush_bio_list); mutex_lock(&delayed_bios_lock); list_for_each_entry_safe(delayed, next, &dc->delayed_bios, list) { + cond_resched(); if (flush_all || time_after_eq(jiffies, delayed->expires)) { struct bio *bio = dm_bio_from_per_bio_data(delayed, sizeof(struct dm_delay_info)); list_del(&delayed->list); bio_list_add(&flush_bio_list, bio); delayed->class->ops--; + continue; + } + + if (!delay_is_fast(dc)) { + if (!start_timer) { + start_timer = true; + next_expires = delayed->expires; + } else { + next_expires = min(next_expires, delayed->expires); + } } } mutex_unlock(&delayed_bios_lock); + if (start_timer) + queue_timeout(dc, next_expires); + flush_bios(bio_list_get(&flush_bio_list)); } @@ -111,7 +127,7 @@ static int flush_worker_fn(void *data) struct delay_c *dc = data; while (!kthread_should_stop()) { - flush_delayed_bios_fast(dc, false); + flush_delayed_bios(dc, false); mutex_lock(&delayed_bios_lock); if (unlikely(list_empty(&dc->delayed_bios))) { set_current_state(TASK_INTERRUPTIBLE); @@ -126,48 +142,12 @@ static int flush_worker_fn(void *data) return 0; } -static void flush_delayed_bios(struct delay_c *dc, bool flush_all) -{ - struct dm_delay_info *delayed, *next; - unsigned long next_expires = 0; - unsigned long start_timer = 0; - struct bio_list flush_bio_list; - bio_list_init(&flush_bio_list); - - mutex_lock(&delayed_bios_lock); - list_for_each_entry_safe(delayed, next, &dc->delayed_bios, list) { - if (flush_all || time_after_eq(jiffies, delayed->expires)) { - struct bio *bio = dm_bio_from_per_bio_data(delayed, - sizeof(struct dm_delay_info)); - list_del(&delayed->list); - bio_list_add(&flush_bio_list, bio); - delayed->class->ops--; - continue; - } - - if (!start_timer) { - start_timer = 1; - next_expires = delayed->expires; - } else - next_expires = min(next_expires, delayed->expires); - } - mutex_unlock(&delayed_bios_lock); - - if (start_timer) - queue_timeout(dc, next_expires); - - flush_bios(bio_list_get(&flush_bio_list)); -} - static void flush_expired_bios(struct work_struct *work) { struct delay_c *dc; dc = container_of(work, struct delay_c, flush_expired_bios); - if (delay_is_fast(dc)) - flush_delayed_bios_fast(dc, false); - else - flush_delayed_bios(dc, false); + flush_delayed_bios(dc, false); } static void delay_dtr(struct dm_target *ti) @@ -354,12 +334,9 @@ static void delay_presuspend(struct dm_target *ti) dc->may_delay = false; mutex_unlock(&delayed_bios_lock); - if (delay_is_fast(dc)) { - flush_delayed_bios_fast(dc, true); - } else { + if (!delay_is_fast(dc)) del_timer_sync(&dc->delay_timer); - flush_delayed_bios(dc, true); - } + flush_delayed_bios(dc, true); } static void delay_resume(struct dm_target *ti)