raid5 bio handling cleanups

raid5 bio handling cleanups

[Christoph Hellwig]

Hi Song,

this series cleans up the raid5 bio handling to take advantage of
the bio allocation interface changes in Jens' for-5.18 branches.

Diffstat:
 raid5-cache.c |   33 ++++++++++++++++-----------------
 raid5-ppl.c   |    5 ++---
 raid5.c       |   25 ++++++++-----------------
 3 files changed, 26 insertions(+), 37 deletions(-)

[PATCH 1/4] raid5-ppl: fully initialize the bio in ppl_new_iounit

[Christoph Hellwig]

We have all the information to pass the bdev and op directly to bio_init,
so do that.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/md/raid5-ppl.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/md/raid5-ppl.c b/drivers/md/raid5-ppl.c
index 3446797fa0aca..f7fdd8292485d 100644
--- a/drivers/md/raid5-ppl.c
+++ b/drivers/md/raid5-ppl.c
@@ -250,7 +250,8 @@ static struct ppl_io_unit *ppl_new_iounit(struct ppl_log *log,
 	INIT_LIST_HEAD(&io->stripe_list);
 	atomic_set(&io->pending_stripes, 0);
 	atomic_set(&io->pending_flushes, 0);
-	bio_init(&io->bio, NULL, io->biovec, PPL_IO_INLINE_BVECS, 0);
+	bio_init(&io->bio, log->rdev->bdev, io->biovec, PPL_IO_INLINE_BVECS,
+		 REQ_OP_WRITE | REQ_FUA);
 
 	pplhdr = page_address(io->header_page);
 	clear_page(pplhdr);
@@ -465,8 +466,6 @@ static void ppl_submit_iounit(struct ppl_io_unit *io)
 
 
 	bio->bi_end_io = ppl_log_endio;
-	bio->bi_opf = REQ_OP_WRITE | REQ_FUA;
-	bio_set_dev(bio, log->rdev->bdev);
 	bio->bi_iter.bi_sector = log->next_io_sector;
 	bio_add_page(bio, io->header_page, PAGE_SIZE, 0);
 	bio->bi_write_hint = ppl_conf->write_hint;
-- 
2.30.2

[PATCH 2/4] raid5-cache: fully initialize flush_bio when needed

[Christoph Hellwig]

Stop using bio_reset and just initialize the bio fully when needed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/md/raid5-cache.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c
index 86e2bb89d9c7b..8907d18c225a9 100644
--- a/drivers/md/raid5-cache.c
+++ b/drivers/md/raid5-cache.c
@@ -1266,6 +1266,8 @@ static void r5l_log_flush_endio(struct bio *bio)
 		r5l_io_run_stripes(io);
 	list_splice_tail_init(&log->flushing_ios, &log->finished_ios);
 	spin_unlock_irqrestore(&log->io_list_lock, flags);
+
+	bio_uninit(bio);
 }
 
 /*
@@ -1301,7 +1303,7 @@ void r5l_flush_stripe_to_raid(struct r5l_log *log)
 
 	if (!do_flush)
 		return;
-	bio_reset(&log->flush_bio, log->rdev->bdev,
+	bio_init(&log->flush_bio, log->rdev->bdev, NULL, 0,
 		  REQ_OP_WRITE | REQ_PREFLUSH);
 	log->flush_bio.bi_end_io = r5l_log_flush_endio;
 	submit_bio(&log->flush_bio);
@@ -3105,7 +3107,6 @@ int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev)
 	INIT_LIST_HEAD(&log->io_end_ios);
 	INIT_LIST_HEAD(&log->flushing_ios);
 	INIT_LIST_HEAD(&log->finished_ios);
-	bio_init(&log->flush_bio, NULL, NULL, 0, 0);
 
 	log->io_kc = KMEM_CACHE(r5l_io_unit, 0);
 	if (!log->io_kc)
-- 
2.30.2

[PATCH 3/4] raid5-cache: statically allocate the recovery ra bio

[Christoph Hellwig]

There is no need to preallocate the bio and reset it when use.  Just
allocate it on-stack and use a bvec places next to the pages used for
it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/md/raid5-cache.c | 28 +++++++++++++---------------
 1 file changed, 13 insertions(+), 15 deletions(-)

diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c
index 8907d18c225a9..a7d50ff9020a8 100644
--- a/drivers/md/raid5-cache.c
+++ b/drivers/md/raid5-cache.c
@@ -1623,10 +1623,10 @@ struct r5l_recovery_ctx {
 	 * just copy data from the pool.
 	 */
 	struct page *ra_pool[R5L_RECOVERY_PAGE_POOL_SIZE];
+	struct bio_vec ra_bvec[R5L_RECOVERY_PAGE_POOL_SIZE];
 	sector_t pool_offset;	/* offset of first page in the pool */
 	int total_pages;	/* total allocated pages */
 	int valid_pages;	/* pages with valid data */
-	struct bio *ra_bio;	/* bio to do the read ahead */
 };
 
 static int r5l_recovery_allocate_ra_pool(struct r5l_log *log,
@@ -1634,11 +1634,6 @@ static int r5l_recovery_allocate_ra_pool(struct r5l_log *log,
 {
 	struct page *page;
 
-	ctx->ra_bio = bio_alloc_bioset(NULL, BIO_MAX_VECS, 0, GFP_KERNEL,
-				       &log->bs);
-	if (!ctx->ra_bio)
-		return -ENOMEM;
-
 	ctx->valid_pages = 0;
 	ctx->total_pages = 0;
 	while (ctx->total_pages < R5L_RECOVERY_PAGE_POOL_SIZE) {
@@ -1650,10 +1645,8 @@ static int r5l_recovery_allocate_ra_pool(struct r5l_log *log,
 		ctx->total_pages += 1;
 	}
 
-	if (ctx->total_pages == 0) {
-		bio_put(ctx->ra_bio);
+	if (ctx->total_pages == 0)
 		return -ENOMEM;
-	}
 
 	ctx->pool_offset = 0;
 	return 0;
@@ -1666,7 +1659,6 @@ static void r5l_recovery_free_ra_pool(struct r5l_log *log,
 
 	for (i = 0; i < ctx->total_pages; ++i)
 		put_page(ctx->ra_pool[i]);
-	bio_put(ctx->ra_bio);
 }
 
 /*
@@ -1679,15 +1671,19 @@ static int r5l_recovery_fetch_ra_pool(struct r5l_log *log,
 				      struct r5l_recovery_ctx *ctx,
 				      sector_t offset)
 {
-	bio_reset(ctx->ra_bio, log->rdev->bdev, REQ_OP_READ);
-	ctx->ra_bio->bi_iter.bi_sector = log->rdev->data_offset + offset;
+	struct bio bio;
+	int ret;
+
+	bio_init(&bio, log->rdev->bdev, ctx->ra_bvec,
+		 R5L_RECOVERY_PAGE_POOL_SIZE, REQ_OP_READ);
+	bio.bi_iter.bi_sector = log->rdev->data_offset + offset;
 
 	ctx->valid_pages = 0;
 	ctx->pool_offset = offset;
 
 	while (ctx->valid_pages < ctx->total_pages) {
-		bio_add_page(ctx->ra_bio,
-			     ctx->ra_pool[ctx->valid_pages], PAGE_SIZE, 0);
+		__bio_add_page(&bio, ctx->ra_pool[ctx->valid_pages], PAGE_SIZE,
+			       0);
 		ctx->valid_pages += 1;
 
 		offset = r5l_ring_add(log, offset, BLOCK_SECTORS);
@@ -1696,7 +1692,9 @@ static int r5l_recovery_fetch_ra_pool(struct r5l_log *log,
 			break;
 	}
 
-	return submit_bio_wait(ctx->ra_bio);
+	ret = submit_bio_wait(&bio);
+	bio_uninit(&bio);
+	return ret;
 }
 
 /*
-- 
2.30.2

[PATCH 4/4] raid5: initialize the stripe_head embeeded bios as needed

[Christoph Hellwig]

Use bio_init to initialize the bios when needed to the full state
instead of a partial initialization plus later setting of dev and op
and bio_reset.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/md/raid5.c | 25 ++++++++-----------------
 1 file changed, 8 insertions(+), 17 deletions(-)

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 8891aaba65964..8bd5f06390ea1 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -1060,6 +1060,7 @@ static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s)
 	int i, disks = sh->disks;
 	struct stripe_head *head_sh = sh;
 	struct bio_list pending_bios = BIO_EMPTY_LIST;
+	struct r5dev *dev;
 	bool should_defer;
 
 	might_sleep();
@@ -1094,8 +1095,9 @@ static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s)
 			op_flags |= REQ_SYNC;
 
 again:
-		bi = &sh->dev[i].req;
-		rbi = &sh->dev[i].rreq; /* For writing to replacement */
+		dev = &sh->dev[i];
+		bi = &dev->req;
+		rbi = &dev->rreq; /* For writing to replacement */
 
 		rcu_read_lock();
 		rrdev = rcu_dereference(conf->disks[i].replacement);
@@ -1171,8 +1173,7 @@ static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s)
 
 			set_bit(STRIPE_IO_STARTED, &sh->state);
 
-			bio_set_dev(bi, rdev->bdev);
-			bio_set_op_attrs(bi, op, op_flags);
+			bio_init(bi, rdev->bdev, &dev->vec, 1, op | op_flags);
 			bi->bi_end_io = op_is_write(op)
 				? raid5_end_write_request
 				: raid5_end_read_request;
@@ -1238,8 +1239,7 @@ static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s)
 
 			set_bit(STRIPE_IO_STARTED, &sh->state);
 
-			bio_set_dev(rbi, rrdev->bdev);
-			bio_set_op_attrs(rbi, op, op_flags);
+			bio_init(rbi, rrdev->bdev, &dev->rvec, 1, op | op_flags);
 			BUG_ON(!op_is_write(op));
 			rbi->bi_end_io = raid5_end_write_request;
 			rbi->bi_private = sh;
@@ -2294,7 +2294,6 @@ static struct stripe_head *alloc_stripe(struct kmem_cache *sc, gfp_t gfp,
 	int disks, struct r5conf *conf)
 {
 	struct stripe_head *sh;
-	int i;
 
 	sh = kmem_cache_zalloc(sc, gfp);
 	if (sh) {
@@ -2307,12 +2306,6 @@ static struct stripe_head *alloc_stripe(struct kmem_cache *sc, gfp_t gfp,
 		atomic_set(&sh->count, 1);
 		sh->raid_conf = conf;
 		sh->log_start = MaxSector;
-		for (i = 0; i < disks; i++) {
-			struct r5dev *dev = &sh->dev[i];
-
-			bio_init(&dev->req, NULL, &dev->vec, 1, 0);
-			bio_init(&dev->rreq, NULL, &dev->rvec, 1, 0);
-		}
 
 		if (raid5_has_ppl(conf)) {
 			sh->ppl_page = alloc_page(gfp);
@@ -2677,7 +2670,6 @@ static void raid5_end_read_request(struct bio * bi)
 		(unsigned long long)sh->sector, i, atomic_read(&sh->count),
 		bi->bi_status);
 	if (i == disks) {
-		bio_reset(bi, NULL, 0);
 		BUG();
 		return;
 	}
@@ -2785,7 +2777,7 @@ static void raid5_end_read_request(struct bio * bi)
 		}
 	}
 	rdev_dec_pending(rdev, conf->mddev);
-	bio_reset(bi, NULL, 0);
+	bio_uninit(bi);
 	clear_bit(R5_LOCKED, &sh->dev[i].flags);
 	set_bit(STRIPE_HANDLE, &sh->state);
 	raid5_release_stripe(sh);
@@ -2823,7 +2815,6 @@ static void raid5_end_write_request(struct bio *bi)
 		(unsigned long long)sh->sector, i, atomic_read(&sh->count),
 		bi->bi_status);
 	if (i == disks) {
-		bio_reset(bi, NULL, 0);
 		BUG();
 		return;
 	}
@@ -2860,7 +2851,7 @@ static void raid5_end_write_request(struct bio *bi)
 	if (sh->batch_head && bi->bi_status && !replacement)
 		set_bit(STRIPE_BATCH_ERR, &sh->batch_head->state);
 
-	bio_reset(bi, NULL, 0);
+	bio_uninit(bi);
 	if (!test_and_clear_bit(R5_DOUBLE_LOCKED, &sh->dev[i].flags))
 		clear_bit(R5_LOCKED, &sh->dev[i].flags);
 	set_bit(STRIPE_HANDLE, &sh->state);
-- 
2.30.2

Re: raid5 bio handling cleanups

[Song Liu]

On Mon, Feb 28, 2022 at 3:25 AM Christoph Hellwig <hch@lst.de> wrote:
>
> Hi Song,
>
> this series cleans up the raid5 bio handling to take advantage of
> the bio allocation interface changes in Jens' for-5.18 branches.

Applied to md-next. Thanks!
Song

Re: raid5 bio handling cleanups

[Christoph Hellwig]

On Wed, Mar 02, 2022 at 04:14:40PM -0800, Song Liu wrote:
> On Mon, Feb 28, 2022 at 3:25 AM Christoph Hellwig <hch@lst.de> wrote:
> >
> > Hi Song,
> >
> > this series cleans up the raid5 bio handling to take advantage of
> > the bio allocation interface changes in Jens' for-5.18 branches.
> 
> Applied to md-next. Thank

Unless I'm missing something these did not make it into the pull
request to Jens, right?

Re: raid5 bio handling cleanups

[Song Liu]

On Tue, Mar 8, 2022 at 10:08 PM Christoph Hellwig <hch@lst.de> wrote:
>
> On Wed, Mar 02, 2022 at 04:14:40PM -0800, Song Liu wrote:
> > On Mon, Feb 28, 2022 at 3:25 AM Christoph Hellwig <hch@lst.de> wrote:
> > >
> > > Hi Song,
> > >
> > > this series cleans up the raid5 bio handling to take advantage of
> > > the bio allocation interface changes in Jens' for-5.18 branches.
> >
> > Applied to md-next. Thank
>
> Unless I'm missing something these did not make it into the pull
> request to Jens, right?

I messed it up. I will send them in the next pull request.

Thanks,
Song

Re: raid5 bio handling cleanups

[Song Liu]

On Tue, Mar 8, 2022 at 10:50 PM Song Liu <song@kernel.org> wrote:
>
> On Tue, Mar 8, 2022 at 10:08 PM Christoph Hellwig <hch@lst.de> wrote:
> >
> > On Wed, Mar 02, 2022 at 04:14:40PM -0800, Song Liu wrote:
> > > On Mon, Feb 28, 2022 at 3:25 AM Christoph Hellwig <hch@lst.de> wrote:
> > > >
> > > > Hi Song,
> > > >
> > > > this series cleans up the raid5 bio handling to take advantage of
> > > > the bio allocation interface changes in Jens' for-5.18 branches.
> > >
> > > Applied to md-next. Thank
> >
> > Unless I'm missing something these did not make it into the pull
> > request to Jens, right?
>
> I messed it up. I will send them in the next pull request.

I just pushed it again to md-next. I will send the pull request tomorrow
or the day after.

Sorry for the confusion.

Song