From ad3fc798800fb7ca04c1dfc439dba946818048d8 Mon Sep 17 00:00:00 2001 From: Guoqing Jiang Date: Tue, 25 May 2021 17:46:16 +0800 Subject: [PATCH] md: revert io stats accounting The commit 41d2d848e5c0 ("md: improve io stats accounting") could cause double fault problem per the report [1], and also it is not correct to change ->bi_end_io if md don't own it, so let's revert it. And io stats accounting will be replemented in later commits. [1]. https://lore.kernel.org/linux-raid/3bf04253-3fad-434a-63a7-20214e38cf26@gmail.com/T/#t Fixes: 41d2d848e5c0 ("md: improve io stats accounting") Signed-off-by: Guoqing Jiang Signed-off-by: Song Liu --- drivers/md/md.c | 45 --------------------------------------------- drivers/md/md.h | 1 - 2 files changed, 46 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 49f897f..7ba00e4 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -441,30 +441,6 @@ check_suspended: } EXPORT_SYMBOL(md_handle_request); -struct md_io { - struct mddev *mddev; - bio_end_io_t *orig_bi_end_io; - void *orig_bi_private; - struct block_device *orig_bi_bdev; - unsigned long start_time; -}; - -static void md_end_io(struct bio *bio) -{ - struct md_io *md_io = bio->bi_private; - struct mddev *mddev = md_io->mddev; - - bio_end_io_acct_remapped(bio, md_io->start_time, md_io->orig_bi_bdev); - - bio->bi_end_io = md_io->orig_bi_end_io; - bio->bi_private = md_io->orig_bi_private; - - mempool_free(md_io, &mddev->md_io_pool); - - if (bio->bi_end_io) - bio->bi_end_io(bio); -} - static blk_qc_t md_submit_bio(struct bio *bio) { const int rw = bio_data_dir(bio); @@ -489,21 +465,6 @@ static blk_qc_t md_submit_bio(struct bio *bio) return BLK_QC_T_NONE; } - if (bio->bi_end_io != md_end_io) { - struct md_io *md_io; - - md_io = mempool_alloc(&mddev->md_io_pool, GFP_NOIO); - md_io->mddev = mddev; - md_io->orig_bi_end_io = bio->bi_end_io; - md_io->orig_bi_private = bio->bi_private; - md_io->orig_bi_bdev = bio->bi_bdev; - - bio->bi_end_io = md_end_io; - bio->bi_private = md_io; - - md_io->start_time = bio_start_io_acct(bio); - } - /* bio could be mergeable after passing to underlayer */ bio->bi_opf &= ~REQ_NOMERGE; @@ -5608,7 +5569,6 @@ static void md_free(struct kobject *ko) bioset_exit(&mddev->bio_set); bioset_exit(&mddev->sync_set); - mempool_exit(&mddev->md_io_pool); kfree(mddev); } @@ -5705,11 +5665,6 @@ static int md_alloc(dev_t dev, char *name) */ mddev->hold_active = UNTIL_STOP; - error = mempool_init_kmalloc_pool(&mddev->md_io_pool, BIO_POOL_SIZE, - sizeof(struct md_io)); - if (error) - goto abort; - error = -ENOMEM; mddev->queue = blk_alloc_queue(NUMA_NO_NODE); if (!mddev->queue) diff --git a/drivers/md/md.h b/drivers/md/md.h index fb7eab5..4da240f 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -487,7 +487,6 @@ struct mddev { struct bio_set sync_set; /* for sync operations like * metadata and bitmap writes */ - mempool_t md_io_pool; /* Generic flush handling. * The last to finish preflush schedules a worker to submit -- 2.7.4