From: Tao Ma Subject: [PATCH 4/4] ext4: Speed up FITRIM by recording flags in ext4_group_info. Date: Wed, 9 Feb 2011 13:57:28 +0800 Message-ID: <1297231048-3458-4-git-send-email-tm@tao.ma> References: <4D522B9B.5070707@tao.ma> Cc: Andreas Dilger , Lukas Czerner To: linux-ext4@vger.kernel.org Return-path: Received: from oproxy2-pub.bluehost.com ([67.222.39.60]:47451 "HELO oproxy2-pub.bluehost.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1750926Ab1BIF6T (ORCPT ); Wed, 9 Feb 2011 00:58:19 -0500 In-Reply-To: <4D522B9B.5070707@tao.ma> Sender: linux-ext4-owner@vger.kernel.org List-ID: From: Tao Ma In ext4, when FITRIM is called every time, we iterate all the groups and do trim one by one. It is a bit time wasting if the group has been trimmed and there is no change since the last trim. So this patch adds a new flag in ext4_group_info->bb_state to indicate that the group has been trimmed, and it will be cleared if some blocks is freed(in release_blocks_on_commit). Another trim_minlen is added in ext4_sb_info to record the last minlen we use to trim the volume, so that if the caller provide a small one, we will go on the trim regardless of the bb_state. The idea is inspired by Andreas and Lukas Czerner. Cc: Andreas Dilger Cc: Lukas Czerner Signed-off-by: Tao Ma --- fs/ext4/ext4.h | 8 +++++++- fs/ext4/mballoc.c | 22 ++++++++++++++++++++++ 2 files changed, 29 insertions(+), 1 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 0c8d97b..684f48e 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1200,6 +1200,9 @@ struct ext4_sb_info { struct ext4_li_request *s_li_request; /* Wait multiplier for lazy initialization thread */ unsigned int s_li_wait_mult; + + /* record the last minlen when FITRIM is called. */ + u64 trim_minlen; }; static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb) @@ -1970,10 +1973,13 @@ struct ext4_group_info { * 5 free 8-block regions. */ }; -#define EXT4_GROUP_INFO_NEED_INIT_BIT 0 +#define EXT4_GROUP_INFO_NEED_INIT_BIT 0 +#define EXT4_GROUP_INFO_HAS_BEEN_TRIMMED 1 #define EXT4_MB_GRP_NEED_INIT(grp) \ (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state))) +#define EXT4_MB_GRP_HAS_BEEN_TRIMMED(grp) \ + (test_bit(EXT4_GROUP_INFO_HAS_BEEN_TRIMMED, &((grp)->bb_state))) #define EXT4_MAX_CONTENTION 8 #define EXT4_CONTENTION_THRESHOLD 2 diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 4eadac8..3f6b809 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -1563,6 +1563,9 @@ static int mb_mark_used(struct ext4_buddy *e4b, struct ext4_free_extent *ex) mb_set_bits(EXT4_MB_BITMAP(e4b), ex->fe_start, len0); mb_check_buddy(e4b); + if (!ret) + EXT4_SB(sb)->trim_minlen = minlen; + return ret; } @@ -2687,6 +2690,16 @@ static void release_blocks_on_commit(journal_t *journal, transaction_t *txn) rb_erase(&entry->node, &(db->bb_free_root)); mb_free_blocks(NULL, &e4b, entry->start_blk, entry->count); + /* + * Clear the trimmed flag for the group so that the next + * ext4_trim_fs can trim it. + * If the volume is mounted with -o discard, online discard + * is supported and the free blocks will be trimmed online. + */ + if (!test_opt(sb, DISCARD)) + clear_bit(EXT4_GROUP_INFO_HAS_BEEN_TRIMMED, + &(db->bb_state)); + if (!db->bb_free_root.rb_node) { /* No more items in the per group rb tree * balance refcounts from ext4_mb_free_metadata() @@ -4772,6 +4785,10 @@ ext4_grpblk_t ext4_trim_all_free(struct super_block *sb, struct ext4_buddy *e4b, ext4_lock_group(sb, group); + if (EXT4_MB_GRP_HAS_BEEN_TRIMMED(e4b->bd_info) && + minblocks >= EXT4_SB(sb)->trim_minlen) + goto out; + trace_ext4_trim_all_free(sb, group, start, max); while (start < max) { @@ -4804,6 +4821,11 @@ ext4_grpblk_t ext4_trim_all_free(struct super_block *sb, struct ext4_buddy *e4b, if ((e4b->bd_info->bb_free - free_count) < minblocks) break; } + + if (!ret) + set_bit(EXT4_GROUP_INFO_HAS_BEEN_TRIMMED, + &(e4b->bd_info->bb_state)); +out: ext4_unlock_group(sb, group); ext4_debug("trimmed %d blocks in the group %d\n", -- 1.6.3.GIT