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md: Revert "md: Fix overflow in is_mddev_idle"

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This reverts commit 3f9f231236.

Using 64bit for 'sync_io' is unnecessary from the gendisk side. This
overflow will not cause any functional impact, except for a UBSAN
warning. Solving this overflow requires introducing additional
calculations and checks which are not necessary. So just keep using
32bit for 'sync_io'.

Signed-off-by: Li Nan <linan122@huawei.com>
Link: https://lore.kernel.org/r/20240507023103.781816-1-linan666@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Li Nan 2024-05-07 10:31:03 +08:00 committed by Jens Axboe
parent 719c15a75e
commit 504fbcffea
3 changed files with 6 additions and 7 deletions
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7
drivers/md/md.c
View File

@ -8577,7 +8577,7 @@ static int is_mddev_idle(struct mddev *mddev, int init)
{
struct md_rdev *rdev;
int idle;
long long curr_events;
int curr_events;
idle = 1;
rcu_read_lock();
@ -8587,9 +8587,8 @@ static int is_mddev_idle(struct mddev *mddev, int init)
if (!init && !blk_queue_io_stat(disk->queue))
continue;
curr_events =
(long long)part_stat_read_accum(disk->part0, sectors) -
atomic64_read(&disk->sync_io);
curr_events = (int)part_stat_read_accum(disk->part0, sectors) -
atomic_read(&disk->sync_io);
/* sync IO will cause sync_io to increase before the disk_stats
* as sync_io is counted when a request starts, and
* disk_stats is counted when it completes.

4
drivers/md/md.h
View File

@ -51,7 +51,7 @@ struct md_rdev {
sector_t sectors; /* Device size (in 512bytes sectors) */
struct mddev *mddev; /* RAID array if running */
long long last_events; /* IO event timestamp */
int last_events; /* IO event timestamp */
/*
* If meta_bdev is non-NULL, it means that a separate device is
@ -622,7 +622,7 @@ extern void mddev_unlock(struct mddev *mddev);
static inline void md_sync_acct(struct block_device *bdev, unsigned long nr_sectors)
{
if (blk_queue_io_stat(bdev->bd_disk->queue))
atomic64_add(nr_sectors, &bdev->bd_disk->sync_io);
atomic_add(nr_sectors, &bdev->bd_disk->sync_io);
}
static inline void md_sync_acct_bio(struct bio *bio, unsigned long nr_sectors)

2
include/linux/blkdev.h
View File

@ -172,7 +172,7 @@ struct gendisk {
struct list_head slave_bdevs;
#endif
struct timer_rand_state *random;
atomic64_t sync_io; /* RAID */
atomic_t sync_io; /* RAID */
struct disk_events *ev;
#ifdef CONFIG_BLK_DEV_ZONED