From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kent Overstreet Subject: Re: [PATCH v2 12/26] raid1: use bio_reset() Date: Tue, 11 Sep 2012 11:28:25 -0700 Message-ID: <20120911182825.GG19739@google.com> References: <1347322957-25260-1-git-send-email-koverstreet@google.com> <1347322957-25260-13-git-send-email-koverstreet@google.com> <20120911145913.3f8a0a30@notabene.brown> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20120911145913.3f8a0a30@notabene.brown> Sender: linux-kernel-owner@vger.kernel.org To: NeilBrown Cc: linux-bcache@vger.kernel.org, linux-kernel@vger.kernel.org, dm-devel@redhat.com, axboe@kernel.dk, tj@kernel.org List-Id: linux-bcache@vger.kernel.org On Tue, Sep 11, 2012 at 02:59:13PM +1000, NeilBrown wrote: > On Mon, 10 Sep 2012 17:22:23 -0700 Kent Overstreet > wrote: > > > I couldn't figure out what sbio->bi_end_io in process_checks() was > > supposed to be, so I took the easy way out. > > Almost. > You save 'sbio->bi_end_io' to 'bi_end_io', then do nothing with it... Whoops :) I think I must've gotten distracted and forgot to finish with that patch, I wasn't setting bi_private either. > > A little way above the 'fixup the bio for reuse' comment you'll find: > > struct bio *sbio = r1_bio->bios[i]; > .... > if (r1_bio->bios[i]->bi_end_io != end_sync_read) > continue; > > which implies that if we don't 'continue', then sbio->bi_end_io == > end_sync_read. Ahh. I remember reading that, but I missed that that was sbio that was being checked. > > So I suspect you want to add > sbio->bi_end_io = end_sync_read; > somewhere after the 'bio_reset()'. > > If you happened to also fix that 'if' that I quoted so that it reads: > > if (sbio->bi_end_io != end_sync_read) > continue; Will do! How's this look? commit 40a4645a4346edd040066baedcf2184ac4211ba7 Author: Kent Overstreet Date: Tue Sep 11 11:26:12 2012 -0700 raid1: use bio_reset() Signed-off-by: Kent Overstreet CC: Jens Axboe CC: NeilBrown diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index ee85154..df68691 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -1851,7 +1851,7 @@ static int process_checks(struct r1bio *r1_bio) struct bio *sbio = r1_bio->bios[i]; int size; - if (r1_bio->bios[i]->bi_end_io != end_sync_read) + if (sbio->bi_end_io != end_sync_read) continue; if (test_bit(BIO_UPTODATE, &sbio->bi_flags)) { @@ -1876,16 +1876,15 @@ static int process_checks(struct r1bio *r1_bio) continue; } /* fixup the bio for reuse */ + bio_reset(sbio); sbio->bi_vcnt = vcnt; sbio->bi_size = r1_bio->sectors << 9; - sbio->bi_idx = 0; - sbio->bi_phys_segments = 0; - sbio->bi_flags &= ~(BIO_POOL_MASK - 1); - sbio->bi_flags |= 1 << BIO_UPTODATE; - sbio->bi_next = NULL; sbio->bi_sector = r1_bio->sector + conf->mirrors[i].rdev->data_offset; sbio->bi_bdev = conf->mirrors[i].rdev->bdev; + sbio->bi_end_io = end_sync_read; + sbio->bi_private = r1_bio; + size = sbio->bi_size; for (j = 0; j < vcnt ; j++) { struct bio_vec *bi; @@ -2426,18 +2425,7 @@ static sector_t sync_request(struct mddev *mddev, sector_t sector_nr, int *skipp for (i = 0; i < conf->raid_disks * 2; i++) { struct md_rdev *rdev; bio = r1_bio->bios[i]; - - /* take from bio_init */ - bio->bi_next = NULL; - bio->bi_flags &= ~(BIO_POOL_MASK-1); - bio->bi_flags |= 1 << BIO_UPTODATE; - bio->bi_rw = READ; - bio->bi_vcnt = 0; - bio->bi_idx = 0; - bio->bi_phys_segments = 0; - bio->bi_size = 0; - bio->bi_end_io = NULL; - bio->bi_private = NULL; + bio_reset(bio); rdev = rcu_dereference(conf->mirrors[i].rdev); if (rdev == NULL ||