[v2] btrfs: scrub: avoid unnecessary extent tree search for striped profiles

Message ID	c21b78ee8bcf22f373beeefb8ee47ee92dfe8f03.1692097289.git.wqu@suse.com (mailing list archive)
State	New, archived
Headers	show Return-Path: <linux-btrfs-owner@vger.kernel.org> From: Qu Wenruo <wqu@suse.com> To: linux-btrfs@vger.kernel.org Subject: [PATCH v2] btrfs: scrub: avoid unnecessary extent tree search for striped profiles Date: Tue, 15 Aug 2023 19:07:19 +0800 Message-ID: <c21b78ee8bcf22f373beeefb8ee47ee92dfe8f03.1692097289.git.wqu@suse.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk
Series	[v2] btrfs: scrub: avoid unnecessary extent tree search for striped profiles \| expand [v2] btrfs: scrub: avoid unnecessary extent tree search for striped profiles

diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c index 6d83f5ed1d93..749818bd9b8f 100644 --- a/fs/btrfs/scrub.c +++ b/fs/btrfs/scrub.c @@ -219,6 +219,14 @@ struct scrub_ctx { * doing the wakeup() call. */ refcount_t refs; + + /* + * Indicate the next logical that is covered by an extent. + * + * This is for striped profiles to skip stripes which doesn't have + * any extent. + */ + u64 found_next; }; struct scrub_warning { @@ -1365,7 +1373,8 @@ static int compare_extent_item_range(struct btrfs_path *path, */ static int find_first_extent_item(struct btrfs_root *extent_root, struct btrfs_path *path, - u64 search_start, u64 search_len) + u64 search_start, u64 search_len, + u64 *found_next_ret) { struct btrfs_fs_info *fs_info = extent_root->fs_info; struct btrfs_key key; @@ -1401,8 +1410,11 @@ static int find_first_extent_item(struct btrfs_root *extent_root, search_forward: while (true) { btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); - if (key.objectid >= search_start + search_len) + if (key.objectid >= search_start + search_len) { + if (found_next_ret) + *found_next_ret = key.objectid; break; + } if (key.type != BTRFS_METADATA_ITEM_KEY && key.type != BTRFS_EXTENT_ITEM_KEY) goto next; @@ -1410,13 +1422,18 @@ static int find_first_extent_item(struct btrfs_root *extent_root, ret = compare_extent_item_range(path, search_start, search_len); if (ret == 0) return ret; - if (ret > 0) + if (ret > 0) { + if (found_next_ret) + *found_next_ret = key.objectid; break; + } next: path->slots[0]++; if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) { ret = btrfs_next_leaf(extent_root, path); if (ret) { + if (ret > 0 && found_next_ret) + *found_next_ret = U64_MAX; /* Either no more item or fatal error */ btrfs_release_path(path); return ret; @@ -1518,7 +1535,8 @@ static int scrub_find_fill_first_stripe(struct btrfs_block_group *bg, struct btrfs_device *dev, u64 physical, int mirror_num, u64 logical_start, u32 logical_len, - struct scrub_stripe *stripe) + struct scrub_stripe *stripe, + u64 *found_next_ret) { struct btrfs_fs_info *fs_info = bg->fs_info; struct btrfs_root *extent_root = btrfs_extent_root(fs_info, bg->start); @@ -1540,7 +1558,7 @@ static int scrub_find_fill_first_stripe(struct btrfs_block_group *bg, ASSERT(logical_start >= bg->start && logical_end <= bg->start + bg->length); ret = find_first_extent_item(extent_root, extent_path, logical_start, - logical_len); + logical_len, found_next_ret); /* Either error or not found. */ if (ret) goto out; @@ -1574,7 +1592,8 @@ static int scrub_find_fill_first_stripe(struct btrfs_block_group *bg, /* Fill the extent info for the remaining sectors. */ while (cur_logical <= stripe_end) { ret = find_first_extent_item(extent_root, extent_path, cur_logical, - stripe_end - cur_logical + 1); + stripe_end - cur_logical + 1, + found_next_ret); if (ret < 0) goto out; if (ret > 0) { @@ -1809,7 +1828,7 @@ static int queue_scrub_stripe(struct scrub_ctx *sctx, struct btrfs_block_group * scrub_reset_stripe(stripe); ret = scrub_find_fill_first_stripe(bg, &sctx->extent_path, &sctx->csum_path, dev, physical, mirror_num, logical, - length, stripe); + length, stripe, &sctx->found_next); /* Either >0 as no more extents or <0 for error. */ if (ret) return ret; @@ -1881,7 +1900,7 @@ static int scrub_raid56_parity_stripe(struct scrub_ctx *sctx, ret = scrub_find_fill_first_stripe(bg, &extent_path, &csum_path, map->stripes[stripe_index].dev, physical, 1, full_stripe_start + btrfs_stripe_nr_to_offset(i), - BTRFS_STRIPE_LEN, stripe); + BTRFS_STRIPE_LEN, stripe, NULL); if (ret < 0) goto out; /* @@ -2124,10 +2143,32 @@ static int scrub_simple_stripe(struct scrub_ctx *sctx, mirror_num); if (ret) return ret; + /* Skip to next stripe which belongs to the target device */ cur_logical += logical_increment; /* For physical offset, we just go to next stripe */ cur_physical += BTRFS_STRIPE_LEN; + + /* No more extent item. all done. */ + if (sctx->found_next >= bg->start + bg->length) { + sctx->stat.last_physical = orig_physical + + div_u64(bg->length, map->num_stripes / + map->sub_stripes); + return 0; + } + /* + * The next found extent is already beyond our stripe. + * Skip to the next extent. + */ + if (sctx->found_next >= cur_logical) { + unsigned int stripes_skipped; + + /* Advance to the next stripe covering sctx->found_next. */ + stripes_skipped = div_u64(sctx->found_next - cur_logical, + logical_increment); + cur_logical += logical_increment * stripes_skipped; + cur_physical += BTRFS_STRIPE_LEN * stripes_skipped; + } } return ret; } @@ -2158,6 +2199,7 @@ static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx, /* Extent_path should be probably released. */ ASSERT(sctx->extent_path.nodes[0] == NULL); + sctx->found_next = chunk_logical; scrub_blocked_if_needed(fs_info); @@ -2235,8 +2277,13 @@ static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx, * using their physical offset. */ while (physical < physical_end) { + u64 full_stripe_start; + u32 full_stripe_len = increment; + ret = get_raid56_logic_offset(physical, stripe_index, map, &logical, &stripe_logical); + full_stripe_start = rounddown(logical, full_stripe_len) + + chunk_logical; logical += chunk_logical; if (ret) { /* it is parity strip */ @@ -2263,6 +2310,25 @@ static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx, next: logical += increment; physical += BTRFS_STRIPE_LEN; + full_stripe_start += full_stripe_len; + + /* No more extent in the block group. */ + if (sctx->found_next >= bg->start + bg->length) { + spin_lock(&sctx->stat_lock); + sctx->stat.last_physical = physical_end; + spin_unlock(&sctx->stat_lock); + goto out; + } + + if (sctx->found_next >= full_stripe_start) { + unsigned int stripes_skipped; + + stripes_skipped = div_u64(sctx->found_next - full_stripe_start, + full_stripe_len); + logical += increment * stripes_skipped; + physical += BTRFS_STRIPE_LEN * stripes_skipped; + } + spin_lock(&sctx->stat_lock); if (stop_loop) sctx->stat.last_physical =

[v2] btrfs: scrub: avoid unnecessary extent tree search for striped profiles

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