From bba681cbb231920a786cd7303462fb2632af6f36 Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Mon, 26 Jan 2015 17:41:23 -0800 Subject: f2fs: introduce a batched trim This patch introduces a batched trimming feature, which submits split discard commands. This is to avoid long latency due to huge trim commands. If fstrim was triggered ranging from 0 to the end of device, we should lock all the checkpoint-related mutexes, resulting in very long latency. Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/f2fs.h | 7 +++++++ fs/f2fs/segment.c | 17 ++++++++++++----- fs/f2fs/super.c | 2 ++ 3 files changed, 21 insertions(+), 5 deletions(-) (limited to 'fs') diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index db1ff55de0bc..337204dfc5cd 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -105,6 +105,10 @@ enum { CP_DISCARD, }; +#define DEF_BATCHED_TRIM_SECTIONS 32 +#define BATCHED_TRIM_SEGMENTS(sbi) \ + (SM_I(sbi)->trim_sections * (sbi)->segs_per_sec) + struct cp_control { int reason; __u64 trim_start; @@ -448,6 +452,9 @@ struct f2fs_sm_info { int nr_discards; /* # of discards in the list */ int max_discards; /* max. discards to be issued */ + /* for batched trimming */ + unsigned int trim_sections; /* # of sections to trim */ + struct list_head sit_entry_set; /* sit entry set list */ unsigned int ipu_policy; /* in-place-update policy */ diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index 5ea57ec153d1..9f278d156d88 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -1066,14 +1066,19 @@ int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct fstrim_range *range) end_segno = (end >= MAX_BLKADDR(sbi)) ? MAIN_SEGS(sbi) - 1 : GET_SEGNO(sbi, end); cpc.reason = CP_DISCARD; - cpc.trim_start = start_segno; - cpc.trim_end = end_segno; cpc.trim_minlen = range->minlen >> sbi->log_blocksize; /* do checkpoint to issue discard commands safely */ - mutex_lock(&sbi->gc_mutex); - write_checkpoint(sbi, &cpc); - mutex_unlock(&sbi->gc_mutex); + for (; start_segno <= end_segno; start_segno = cpc.trim_end + 1) { + cpc.trim_start = start_segno; + cpc.trim_end = min_t(unsigned int, rounddown(start_segno + + BATCHED_TRIM_SEGMENTS(sbi), + sbi->segs_per_sec) - 1, end_segno); + + mutex_lock(&sbi->gc_mutex); + write_checkpoint(sbi, &cpc); + mutex_unlock(&sbi->gc_mutex); + } out: range->len = cpc.trimmed << sbi->log_blocksize; return 0; @@ -2127,6 +2132,8 @@ int build_segment_manager(struct f2fs_sb_info *sbi) sm_info->nr_discards = 0; sm_info->max_discards = 0; + sm_info->trim_sections = DEF_BATCHED_TRIM_SECTIONS; + INIT_LIST_HEAD(&sm_info->sit_entry_set); if (test_opt(sbi, FLUSH_MERGE) && !f2fs_readonly(sbi->sb)) { diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index 1e92c2ea6bc1..f2fe666a6ea9 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -195,6 +195,7 @@ F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_no_gc_sleep_time, no_gc_sleep_time); F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_idle, gc_idle); F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, reclaim_segments, rec_prefree_segments); F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, max_small_discards, max_discards); +F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, batched_trim_sections, trim_sections); F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, ipu_policy, ipu_policy); F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_ipu_util, min_ipu_util); F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_fsync_blocks, min_fsync_blocks); @@ -210,6 +211,7 @@ static struct attribute *f2fs_attrs[] = { ATTR_LIST(gc_idle), ATTR_LIST(reclaim_segments), ATTR_LIST(max_small_discards), + ATTR_LIST(batched_trim_sections), ATTR_LIST(ipu_policy), ATTR_LIST(min_ipu_util), ATTR_LIST(min_fsync_blocks), -- cgit v1.2.3