Change long from v1: o add description o change the # of batched segments suggested by Chao o make consistent for # of batched segments
This patch introduces a batched trimming feature, which submits split discard commands. 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. Signed-off-by: Jaegeuk Kim <[email protected]> --- fs/f2fs/f2fs.h | 2 ++ fs/f2fs/segment.c | 16 +++++++++++----- 2 files changed, 13 insertions(+), 5 deletions(-) diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index 8231a59..ec5e66f 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -105,6 +105,8 @@ enum { CP_DISCARD, }; +#define BATCHED_TRIM_SEGMENTS(sbi) (((sbi)->segs_per_sec) << 5) + struct cp_control { int reason; __u64 trim_start; diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index 5ea57ec..b85bb97 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -1066,14 +1066,20 @@ 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 += BATCHED_TRIM_SEGMENTS(sbi)) { + cpc.trim_start = start_segno; + cpc.trim_end = min_t(unsigned int, + start_segno + BATCHED_TRIM_SEGMENTS (sbi) - 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; -- 2.1.1 ------------------------------------------------------------------------------ Dive into the World of Parallel Programming. The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ _______________________________________________ Linux-f2fs-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
