Drivers shouldn't really mess with the readahead size, as that is a VM concept. Instead set it based on the optimal I/O size by lifting the algorithm from the md driver when registering the disk. Also set bdi->io_pages there as well by applying the same scheme based on max_sectors.
Signed-off-by: Christoph Hellwig <[email protected]> Reviewed-by: Johannes Thumshirn <[email protected]> --- block/blk-settings.c | 5 ++--- block/blk-sysfs.c | 9 +++++++++ drivers/block/aoe/aoeblk.c | 1 - drivers/block/drbd/drbd_nl.c | 12 +----------- drivers/md/bcache/super.c | 3 --- drivers/md/raid0.c | 16 ---------------- drivers/md/raid10.c | 24 +----------------------- drivers/md/raid5.c | 13 +------------ 8 files changed, 14 insertions(+), 69 deletions(-) diff --git a/block/blk-settings.c b/block/blk-settings.c index 76a7e03bcd6cac..01049e9b998f1d 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -452,6 +452,8 @@ EXPORT_SYMBOL(blk_limits_io_opt); void blk_queue_io_opt(struct request_queue *q, unsigned int opt) { blk_limits_io_opt(&q->limits, opt); + q->backing_dev_info->ra_pages = + max(queue_io_opt(q) * 2 / PAGE_SIZE, VM_READAHEAD_PAGES); } EXPORT_SYMBOL(blk_queue_io_opt); @@ -628,9 +630,6 @@ void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, printk(KERN_NOTICE "%s: Warning: Device %s is misaligned\n", top, bottom); } - - t->backing_dev_info->io_pages = - t->limits.max_sectors >> (PAGE_SHIFT - 9); } EXPORT_SYMBOL(disk_stack_limits); diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 81722cdcf0cb21..83915b4a1fc3ad 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -854,6 +854,15 @@ int blk_register_queue(struct gendisk *disk) percpu_ref_switch_to_percpu(&q->q_usage_counter); } + /* + * For read-ahead of large files to be effective, we need to read ahead + * at least twice the optimal I/O size. + */ + q->backing_dev_info->ra_pages = + max(queue_io_opt(q) * 2 / PAGE_SIZE, VM_READAHEAD_PAGES); + q->backing_dev_info->io_pages = + queue_max_sectors(q) >> (PAGE_SHIFT - 9); + ret = blk_trace_init_sysfs(dev); if (ret) return ret; diff --git a/drivers/block/aoe/aoeblk.c b/drivers/block/aoe/aoeblk.c index d8cfc233e64b93..c34e71b0c4a98c 100644 --- a/drivers/block/aoe/aoeblk.c +++ b/drivers/block/aoe/aoeblk.c @@ -406,7 +406,6 @@ aoeblk_gdalloc(void *vp) WARN_ON(d->gd); WARN_ON(d->flags & DEVFL_UP); blk_queue_max_hw_sectors(q, BLK_DEF_MAX_SECTORS); - q->backing_dev_info->ra_pages = SZ_2M / PAGE_SIZE; blk_queue_io_opt(q, SZ_2M); d->bufpool = mp; d->blkq = gd->queue = q; diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c index aaff5bde391506..f8fb1c9b1bb6c1 100644 --- a/drivers/block/drbd/drbd_nl.c +++ b/drivers/block/drbd/drbd_nl.c @@ -1360,18 +1360,8 @@ static void drbd_setup_queue_param(struct drbd_device *device, struct drbd_backi decide_on_discard_support(device, q, b, discard_zeroes_if_aligned); decide_on_write_same_support(device, q, b, o, disable_write_same); - if (b) { + if (b) blk_stack_limits(&q->limits, &b->limits, 0); - - if (q->backing_dev_info->ra_pages != - b->backing_dev_info->ra_pages) { - drbd_info(device, "Adjusting my ra_pages to backing device's (%lu -> %lu)\n", - q->backing_dev_info->ra_pages, - b->backing_dev_info->ra_pages); - q->backing_dev_info->ra_pages = - b->backing_dev_info->ra_pages; - } - } fixup_discard_if_not_supported(q); fixup_write_zeroes(device, q); } diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index 48113005ed86ad..6bfa771673623e 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -1427,9 +1427,6 @@ static int cached_dev_init(struct cached_dev *dc, unsigned int block_size) if (ret) return ret; - dc->disk.disk->queue->backing_dev_info->ra_pages = - max(dc->disk.disk->queue->backing_dev_info->ra_pages, - q->backing_dev_info->ra_pages); blk_queue_io_opt(dc->disk.disk->queue, max(queue_io_opt(dc->disk.disk->queue), queue_io_opt(q))); diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c index f54a449f97aa79..aa2d7279176880 100644 --- a/drivers/md/raid0.c +++ b/drivers/md/raid0.c @@ -410,22 +410,6 @@ static int raid0_run(struct mddev *mddev) mdname(mddev), (unsigned long long)mddev->array_sectors); - if (mddev->queue) { - /* calculate the max read-ahead size. - * For read-ahead of large files to be effective, we need to - * readahead at least twice a whole stripe. i.e. number of devices - * multiplied by chunk size times 2. - * If an individual device has an ra_pages greater than the - * chunk size, then we will not drive that device as hard as it - * wants. We consider this a configuration error: a larger - * chunksize should be used in that case. - */ - int stripe = mddev->raid_disks * - (mddev->chunk_sectors << 9) / PAGE_SIZE; - if (mddev->queue->backing_dev_info->ra_pages < 2* stripe) - mddev->queue->backing_dev_info->ra_pages = 2* stripe; - } - dump_zones(mddev); ret = md_integrity_register(mddev); diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 9956a04ac13bd6..5d1bdee313ec33 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -3873,19 +3873,6 @@ static int raid10_run(struct mddev *mddev) mddev->resync_max_sectors = size; set_bit(MD_FAILFAST_SUPPORTED, &mddev->flags); - if (mddev->queue) { - int stripe = conf->geo.raid_disks * - ((mddev->chunk_sectors << 9) / PAGE_SIZE); - - /* Calculate max read-ahead size. - * We need to readahead at least twice a whole stripe.... - * maybe... - */ - stripe /= conf->geo.near_copies; - if (mddev->queue->backing_dev_info->ra_pages < 2 * stripe) - mddev->queue->backing_dev_info->ra_pages = 2 * stripe; - } - if (md_integrity_register(mddev)) goto out_free_conf; @@ -4723,17 +4710,8 @@ static void end_reshape(struct r10conf *conf) conf->reshape_safe = MaxSector; spin_unlock_irq(&conf->device_lock); - /* read-ahead size must cover two whole stripes, which is - * 2 * (datadisks) * chunksize where 'n' is the number of raid devices - */ - if (conf->mddev->queue) { - int stripe = conf->geo.raid_disks * - ((conf->mddev->chunk_sectors << 9) / PAGE_SIZE); - stripe /= conf->geo.near_copies; - if (conf->mddev->queue->backing_dev_info->ra_pages < 2 * stripe) - conf->mddev->queue->backing_dev_info->ra_pages = 2 * stripe; + if (conf->mddev->queue) raid10_set_io_opt(conf); - } conf->fullsync = 0; } diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 9a7d1250894ef1..7ace1f76b14736 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -7522,8 +7522,6 @@ static int raid5_run(struct mddev *mddev) int data_disks = conf->previous_raid_disks - conf->max_degraded; int stripe = data_disks * ((mddev->chunk_sectors << 9) / PAGE_SIZE); - if (mddev->queue->backing_dev_info->ra_pages < 2 * stripe) - mddev->queue->backing_dev_info->ra_pages = 2 * stripe; chunk_size = mddev->chunk_sectors << 9; blk_queue_io_min(mddev->queue, chunk_size); @@ -8111,17 +8109,8 @@ static void end_reshape(struct r5conf *conf) spin_unlock_irq(&conf->device_lock); wake_up(&conf->wait_for_overlap); - /* read-ahead size must cover two whole stripes, which is - * 2 * (datadisks) * chunksize where 'n' is the number of raid devices - */ - if (conf->mddev->queue) { - int data_disks = conf->raid_disks - conf->max_degraded; - int stripe = data_disks * ((conf->chunk_sectors << 9) - / PAGE_SIZE); - if (conf->mddev->queue->backing_dev_info->ra_pages < 2 * stripe) - conf->mddev->queue->backing_dev_info->ra_pages = 2 * stripe; + if (conf->mddev->queue) raid5_set_io_opt(conf); - } } } -- 2.28.0
