From 2a0dfac7457c2c8629a253499607b853c2f53786 Mon Sep 17 00:00:00 2001 From: Lars Ellenberg Date: Mon, 8 Jan 2007 15:02:42 -0800 Subject: [PATCH] [PATCH] md: pass down BIO_RW_SYNC in raid{1,10} md raidX make_request functions strip off the BIO_RW_SYNC flag, thus introducing additional latency. Fixing this in raid1 and raid10 seems to be straightforward enough. For our particular usage case in DRBD, passing this flag improved some initialization time from ~5 minutes to ~5 seconds. Acked-by: NeilBrown Signed-off-by: Lars Ellenberg Acked-by: Jens Axboe Cc: Signed-off-by: Andrew Morton Signed-off-by: Chris Wright --- drivers/md/raid1.c | 13 +++++++++---- drivers/md/raid10.c | 11 ++++++++--- 2 files changed, 17 insertions(+), 7 deletions(-) diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 656fae912fe35..6b29501a25c74 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -775,6 +775,7 @@ static int make_request(request_queue_t *q, struct bio * bio) struct bio_list bl; struct page **behind_pages = NULL; const int rw = bio_data_dir(bio); + const int do_sync = bio_sync(bio); int do_barriers; /* @@ -835,7 +836,7 @@ static int make_request(request_queue_t *q, struct bio * bio) read_bio->bi_sector = r1_bio->sector + mirror->rdev->data_offset; read_bio->bi_bdev = mirror->rdev->bdev; read_bio->bi_end_io = raid1_end_read_request; - read_bio->bi_rw = READ; + read_bio->bi_rw = READ | do_sync; read_bio->bi_private = r1_bio; generic_make_request(read_bio); @@ -906,7 +907,7 @@ static int make_request(request_queue_t *q, struct bio * bio) mbio->bi_sector = r1_bio->sector + conf->mirrors[i].rdev->data_offset; mbio->bi_bdev = conf->mirrors[i].rdev->bdev; mbio->bi_end_io = raid1_end_write_request; - mbio->bi_rw = WRITE | do_barriers; + mbio->bi_rw = WRITE | do_barriers | do_sync; mbio->bi_private = r1_bio; if (behind_pages) { @@ -941,6 +942,8 @@ static int make_request(request_queue_t *q, struct bio * bio) blk_plug_device(mddev->queue); spin_unlock_irqrestore(&conf->device_lock, flags); + if (do_sync) + md_wakeup_thread(mddev->thread); #if 0 while ((bio = bio_list_pop(&bl)) != NULL) generic_make_request(bio); @@ -1541,6 +1544,7 @@ static void raid1d(mddev_t *mddev) * We already have a nr_pending reference on these rdevs. */ int i; + const int do_sync = bio_sync(r1_bio->master_bio); clear_bit(R1BIO_BarrierRetry, &r1_bio->state); clear_bit(R1BIO_Barrier, &r1_bio->state); for (i=0; i < conf->raid_disks; i++) @@ -1561,7 +1565,7 @@ static void raid1d(mddev_t *mddev) conf->mirrors[i].rdev->data_offset; bio->bi_bdev = conf->mirrors[i].rdev->bdev; bio->bi_end_io = raid1_end_write_request; - bio->bi_rw = WRITE; + bio->bi_rw = WRITE | do_sync; bio->bi_private = r1_bio; r1_bio->bios[i] = bio; generic_make_request(bio); @@ -1593,6 +1597,7 @@ static void raid1d(mddev_t *mddev) (unsigned long long)r1_bio->sector); raid_end_bio_io(r1_bio); } else { + const int do_sync = bio_sync(r1_bio->master_bio); r1_bio->bios[r1_bio->read_disk] = mddev->ro ? IO_BLOCKED : NULL; r1_bio->read_disk = disk; @@ -1608,7 +1613,7 @@ static void raid1d(mddev_t *mddev) bio->bi_sector = r1_bio->sector + rdev->data_offset; bio->bi_bdev = rdev->bdev; bio->bi_end_io = raid1_end_read_request; - bio->bi_rw = READ; + bio->bi_rw = READ | do_sync; bio->bi_private = r1_bio; unplug = 1; generic_make_request(bio); diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 7492d6033ac63..3bb4cae2c4a45 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -782,6 +782,7 @@ static int make_request(request_queue_t *q, struct bio * bio) int i; int chunk_sects = conf->chunk_mask + 1; const int rw = bio_data_dir(bio); + const int do_sync = bio_sync(bio); struct bio_list bl; unsigned long flags; @@ -863,7 +864,7 @@ static int make_request(request_queue_t *q, struct bio * bio) mirror->rdev->data_offset; read_bio->bi_bdev = mirror->rdev->bdev; read_bio->bi_end_io = raid10_end_read_request; - read_bio->bi_rw = READ; + read_bio->bi_rw = READ | do_sync; read_bio->bi_private = r10_bio; generic_make_request(read_bio); @@ -909,7 +910,7 @@ static int make_request(request_queue_t *q, struct bio * bio) conf->mirrors[d].rdev->data_offset; mbio->bi_bdev = conf->mirrors[d].rdev->bdev; mbio->bi_end_io = raid10_end_write_request; - mbio->bi_rw = WRITE; + mbio->bi_rw = WRITE | do_sync; mbio->bi_private = r10_bio; atomic_inc(&r10_bio->remaining); @@ -922,6 +923,9 @@ static int make_request(request_queue_t *q, struct bio * bio) blk_plug_device(mddev->queue); spin_unlock_irqrestore(&conf->device_lock, flags); + if (do_sync) + md_wakeup_thread(mddev->thread); + return 0; } @@ -1563,6 +1567,7 @@ static void raid10d(mddev_t *mddev) (unsigned long long)r10_bio->sector); raid_end_bio_io(r10_bio); } else { + const int do_sync = bio_sync(r10_bio->master_bio); rdev = conf->mirrors[mirror].rdev; if (printk_ratelimit()) printk(KERN_ERR "raid10: %s: redirecting sector %llu to" @@ -1574,7 +1579,7 @@ static void raid10d(mddev_t *mddev) bio->bi_sector = r10_bio->devs[r10_bio->read_slot].addr + rdev->data_offset; bio->bi_bdev = rdev->bdev; - bio->bi_rw = READ; + bio->bi_rw = READ | do_sync; bio->bi_private = r10_bio; bio->bi_end_io = raid10_end_read_request; unplug = 1; -- 2.47.2