From 7eaceaccab5f40bbfda044629a6298616aeaed50 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Thu, 10 Mar 2011 08:52:07 +0100 Subject: block: remove per-queue plugging Code has been converted over to the new explicit on-stack plugging, and delay users have been converted to use the new API for that. So lets kill off the old plugging along with aops->sync_page(). Signed-off-by: Jens Axboe --- fs/btrfs/disk-io.c | 79 ----------------------------------------------- fs/btrfs/inode.c | 1 - fs/btrfs/volumes.c | 91 +++++++----------------------------------------------- 3 files changed, 11 insertions(+), 160 deletions(-) (limited to 'fs/btrfs') diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index e1aa8d607bc7..ada1f6bd0a57 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -847,7 +847,6 @@ static const struct address_space_operations btree_aops = { .writepages = btree_writepages, .releasepage = btree_releasepage, .invalidatepage = btree_invalidatepage, - .sync_page = block_sync_page, #ifdef CONFIG_MIGRATION .migratepage = btree_migratepage, #endif @@ -1330,82 +1329,6 @@ static int btrfs_congested_fn(void *congested_data, int bdi_bits) return ret; } -/* - * this unplugs every device on the box, and it is only used when page - * is null - */ -static void __unplug_io_fn(struct backing_dev_info *bdi, struct page *page) -{ - struct btrfs_device *device; - struct btrfs_fs_info *info; - - info = (struct btrfs_fs_info *)bdi->unplug_io_data; - list_for_each_entry(device, &info->fs_devices->devices, dev_list) { - if (!device->bdev) - continue; - - bdi = blk_get_backing_dev_info(device->bdev); - if (bdi->unplug_io_fn) - bdi->unplug_io_fn(bdi, page); - } -} - -static void btrfs_unplug_io_fn(struct backing_dev_info *bdi, struct page *page) -{ - struct inode *inode; - struct extent_map_tree *em_tree; - struct extent_map *em; - struct address_space *mapping; - u64 offset; - - /* the generic O_DIRECT read code does this */ - if (1 || !page) { - __unplug_io_fn(bdi, page); - return; - } - - /* - * page->mapping may change at any time. Get a consistent copy - * and use that for everything below - */ - smp_mb(); - mapping = page->mapping; - if (!mapping) - return; - - inode = mapping->host; - - /* - * don't do the expensive searching for a small number of - * devices - */ - if (BTRFS_I(inode)->root->fs_info->fs_devices->open_devices <= 2) { - __unplug_io_fn(bdi, page); - return; - } - - offset = page_offset(page); - - em_tree = &BTRFS_I(inode)->extent_tree; - read_lock(&em_tree->lock); - em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE); - read_unlock(&em_tree->lock); - if (!em) { - __unplug_io_fn(bdi, page); - return; - } - - if (em->block_start >= EXTENT_MAP_LAST_BYTE) { - free_extent_map(em); - __unplug_io_fn(bdi, page); - return; - } - offset = offset - em->start; - btrfs_unplug_page(&BTRFS_I(inode)->root->fs_info->mapping_tree, - em->block_start + offset, page); - free_extent_map(em); -} - /* * If this fails, caller must call bdi_destroy() to get rid of the * bdi again. @@ -1420,8 +1343,6 @@ static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi) return err; bdi->ra_pages = default_backing_dev_info.ra_pages; - bdi->unplug_io_fn = btrfs_unplug_io_fn; - bdi->unplug_io_data = info; bdi->congested_fn = btrfs_congested_fn; bdi->congested_data = info; return 0; diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index fb9bd7832b6d..462e08e724b0 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -7218,7 +7218,6 @@ static const struct address_space_operations btrfs_aops = { .writepage = btrfs_writepage, .writepages = btrfs_writepages, .readpages = btrfs_readpages, - .sync_page = block_sync_page, .direct_IO = btrfs_direct_IO, .invalidatepage = btrfs_invalidatepage, .releasepage = btrfs_releasepage, diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index af7dbca15276..6e0e82a1b188 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -162,7 +162,6 @@ static noinline int run_scheduled_bios(struct btrfs_device *device) struct bio *cur; int again = 0; unsigned long num_run; - unsigned long num_sync_run; unsigned long batch_run = 0; unsigned long limit; unsigned long last_waited = 0; @@ -173,11 +172,6 @@ static noinline int run_scheduled_bios(struct btrfs_device *device) limit = btrfs_async_submit_limit(fs_info); limit = limit * 2 / 3; - /* we want to make sure that every time we switch from the sync - * list to the normal list, we unplug - */ - num_sync_run = 0; - loop: spin_lock(&device->io_lock); @@ -223,15 +217,6 @@ loop_lock: spin_unlock(&device->io_lock); - /* - * if we're doing the regular priority list, make sure we unplug - * for any high prio bios we've sent down - */ - if (pending_bios == &device->pending_bios && num_sync_run > 0) { - num_sync_run = 0; - blk_run_backing_dev(bdi, NULL); - } - while (pending) { rmb(); @@ -259,19 +244,11 @@ loop_lock: BUG_ON(atomic_read(&cur->bi_cnt) == 0); - if (cur->bi_rw & REQ_SYNC) - num_sync_run++; - submit_bio(cur->bi_rw, cur); num_run++; batch_run++; - if (need_resched()) { - if (num_sync_run) { - blk_run_backing_dev(bdi, NULL); - num_sync_run = 0; - } + if (need_resched()) cond_resched(); - } /* * we made progress, there is more work to do and the bdi @@ -304,13 +281,8 @@ loop_lock: * against it before looping */ last_waited = ioc->last_waited; - if (need_resched()) { - if (num_sync_run) { - blk_run_backing_dev(bdi, NULL); - num_sync_run = 0; - } + if (need_resched()) cond_resched(); - } continue; } spin_lock(&device->io_lock); @@ -323,22 +295,6 @@ loop_lock: } } - if (num_sync_run) { - num_sync_run = 0; - blk_run_backing_dev(bdi, NULL); - } - /* - * IO has already been through a long path to get here. Checksumming, - * async helper threads, perhaps compression. We've done a pretty - * good job of collecting a batch of IO and should just unplug - * the device right away. - * - * This will help anyone who is waiting on the IO, they might have - * already unplugged, but managed to do so before the bio they - * cared about found its way down here. - */ - blk_run_backing_dev(bdi, NULL); - cond_resched(); if (again) goto loop; @@ -2948,7 +2904,7 @@ static int find_live_mirror(struct map_lookup *map, int first, int num, static int __btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, u64 logical, u64 *length, struct btrfs_multi_bio **multi_ret, - int mirror_num, struct page *unplug_page) + int mirror_num) { struct extent_map *em; struct map_lookup *map; @@ -2980,11 +2936,6 @@ again: em = lookup_extent_mapping(em_tree, logical, *length); read_unlock(&em_tree->lock); - if (!em && unplug_page) { - kfree(multi); - return 0; - } - if (!em) { printk(KERN_CRIT "unable to find logical %llu len %llu\n", (unsigned long long)logical, @@ -3040,13 +2991,13 @@ again: *length = em->len - offset; } - if (!multi_ret && !unplug_page) + if (!multi_ret) goto out; num_stripes = 1; stripe_index = 0; if (map->type & BTRFS_BLOCK_GROUP_RAID1) { - if (unplug_page || (rw & REQ_WRITE)) + if (rw & REQ_WRITE) num_stripes = map->num_stripes; else if (mirror_num) stripe_index = mirror_num - 1; @@ -3068,7 +3019,7 @@ again: stripe_index = do_div(stripe_nr, factor); stripe_index *= map->sub_stripes; - if (unplug_page || (rw & REQ_WRITE)) + if (rw & REQ_WRITE) num_stripes = map->sub_stripes; else if (mirror_num) stripe_index += mirror_num - 1; @@ -3088,22 +3039,10 @@ again: BUG_ON(stripe_index >= map->num_stripes); for (i = 0; i < num_stripes; i++) { - if (unplug_page) { - struct btrfs_device *device; - struct backing_dev_info *bdi; - - device = map->stripes[stripe_index].dev; - if (device->bdev) { - bdi = blk_get_backing_dev_info(device->bdev); - if (bdi->unplug_io_fn) - bdi->unplug_io_fn(bdi, unplug_page); - } - } else { - multi->stripes[i].physical = - map->stripes[stripe_index].physical + - stripe_offset + stripe_nr * map->stripe_len; - multi->stripes[i].dev = map->stripes[stripe_index].dev; - } + multi->stripes[i].physical = + map->stripes[stripe_index].physical + + stripe_offset + stripe_nr * map->stripe_len; + multi->stripes[i].dev = map->stripes[stripe_index].dev; stripe_index++; } if (multi_ret) { @@ -3121,7 +3060,7 @@ int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, struct btrfs_multi_bio **multi_ret, int mirror_num) { return __btrfs_map_block(map_tree, rw, logical, length, multi_ret, - mirror_num, NULL); + mirror_num); } int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree, @@ -3189,14 +3128,6 @@ int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree, return 0; } -int btrfs_unplug_page(struct btrfs_mapping_tree *map_tree, - u64 logical, struct page *page) -{ - u64 length = PAGE_CACHE_SIZE; - return __btrfs_map_block(map_tree, READ, logical, &length, - NULL, 0, page); -} - static void end_bio_multi_stripe(struct bio *bio, int err) { struct btrfs_multi_bio *multi = bio->bi_private; -- cgit v1.2.3 From 721a9602e6607417c6bc15b18e97a2f35266c690 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Wed, 9 Mar 2011 11:56:30 +0100 Subject: block: kill off REQ_UNPLUG With the plugging now being explicitly controlled by the submitter, callers need not pass down unplugging hints to the block layer. If they want to unplug, it's because they manually plugged on their own - in which case, they should just unplug at will. Signed-off-by: Jens Axboe --- fs/btrfs/extent_io.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/btrfs') diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 92ac5192c518..b76f7cd47401 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -2182,7 +2182,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc, unsigned long nr_written = 0; if (wbc->sync_mode == WB_SYNC_ALL) - write_flags = WRITE_SYNC_PLUG; + write_flags = WRITE_SYNC; else write_flags = WRITE; -- cgit v1.2.3