From 8bb4f2535cf7c3e3aeaed8b3c7c7a116844c41db Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Tue, 29 May 2018 09:58:42 -0700 Subject: [PATCH] f2fs: issue discard commands proactively in high fs utilization In the high utilization like over 80%, we don't expect huge # of large discard commands, but do many small pending discards which affects FTL GCs a lot. Let's issue them in that case. Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/f2fs.h | 3 +-- fs/f2fs/segment.c | 71 ++++++++++++++++++++++++++++++------------------------- 2 files changed, 40 insertions(+), 34 deletions(-) diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index e852ac9..27231fe 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -186,6 +186,7 @@ enum { #define DEF_MAX_DISCARD_LEN 512 /* Max. 2MB per discard */ #define DEF_MIN_DISCARD_ISSUE_TIME 50 /* 50 ms, if exists */ #define DEF_MAX_DISCARD_ISSUE_TIME 60000 /* 60 s, if no candidates */ +#define DEF_DISCARD_URGENT_UTIL 80 /* do more discard over 80% */ #define DEF_CP_INTERVAL 60 /* 60 secs */ #define DEF_IDLE_INTERVAL 5 /* 5 secs */ @@ -2777,8 +2778,6 @@ int f2fs_flush_device_cache(struct f2fs_sb_info *sbi); void destroy_flush_cmd_control(struct f2fs_sb_info *sbi, bool free); void invalidate_blocks(struct f2fs_sb_info *sbi, block_t addr); bool is_checkpointed_data(struct f2fs_sb_info *sbi, block_t blkaddr); -void init_discard_policy(struct discard_policy *dpolicy, int discard_type, - unsigned int granularity); void drop_discard_cmd(struct f2fs_sb_info *sbi); void stop_discard_thread(struct f2fs_sb_info *sbi); bool f2fs_wait_discard_bios(struct f2fs_sb_info *sbi); diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index 6e40e53..8c1f7a6b 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -915,6 +915,38 @@ static void __check_sit_bitmap(struct f2fs_sb_info *sbi, #endif } +static void __init_discard_policy(struct f2fs_sb_info *sbi, + struct discard_policy *dpolicy, + int discard_type, unsigned int granularity) +{ + /* common policy */ + dpolicy->type = discard_type; + dpolicy->sync = true; + dpolicy->granularity = granularity; + + dpolicy->max_requests = DEF_MAX_DISCARD_REQUEST; + dpolicy->io_aware_gran = MAX_PLIST_NUM; + + if (discard_type == DPOLICY_BG) { + dpolicy->min_interval = DEF_MIN_DISCARD_ISSUE_TIME; + dpolicy->max_interval = DEF_MAX_DISCARD_ISSUE_TIME; + dpolicy->io_aware = true; + if (utilization(sbi) > DEF_DISCARD_URGENT_UTIL) { + dpolicy->granularity = 1; + dpolicy->max_interval = DEF_MIN_DISCARD_ISSUE_TIME; + } + } else if (discard_type == DPOLICY_FORCE) { + dpolicy->min_interval = DEF_MIN_DISCARD_ISSUE_TIME; + dpolicy->max_interval = DEF_MAX_DISCARD_ISSUE_TIME; + dpolicy->io_aware = false; + } else if (discard_type == DPOLICY_FSTRIM) { + dpolicy->io_aware = false; + } else if (discard_type == DPOLICY_UMOUNT) { + dpolicy->io_aware = false; + } +} + + /* this function is copied from blkdev_issue_discard from block/blk-lib.c */ static void __submit_discard_cmd(struct f2fs_sb_info *sbi, struct discard_policy *dpolicy, @@ -1278,9 +1310,9 @@ static void __wait_all_discard_cmd(struct f2fs_sb_info *sbi, } /* wait all */ - init_discard_policy(&dp, DPOLICY_FSTRIM, 1); + __init_discard_policy(sbi, &dp, DPOLICY_FSTRIM, 1); __wait_discard_cmd_range(sbi, &dp, 0, UINT_MAX); - init_discard_policy(&dp, DPOLICY_UMOUNT, 1); + __init_discard_policy(sbi, &dp, DPOLICY_UMOUNT, 1); __wait_discard_cmd_range(sbi, &dp, 0, UINT_MAX); } @@ -1326,7 +1358,8 @@ bool f2fs_wait_discard_bios(struct f2fs_sb_info *sbi) struct discard_policy dpolicy; bool dropped; - init_discard_policy(&dpolicy, DPOLICY_UMOUNT, dcc->discard_granularity); + __init_discard_policy(sbi, &dpolicy, DPOLICY_UMOUNT, + dcc->discard_granularity); __issue_discard_cmd(sbi, &dpolicy); dropped = __drop_discard_cmd(sbi); @@ -1347,7 +1380,7 @@ static int issue_discard_thread(void *data) set_freezable(); do { - init_discard_policy(&dpolicy, DPOLICY_BG, + __init_discard_policy(sbi, &dpolicy, DPOLICY_BG, dcc->discard_granularity); wait_event_interruptible_timeout(*q, @@ -1365,7 +1398,7 @@ static int issue_discard_thread(void *data) dcc->discard_wake = 0; if (sbi->gc_thread && sbi->gc_thread->gc_urgent) - init_discard_policy(&dpolicy, DPOLICY_FORCE, 1); + __init_discard_policy(sbi, &dpolicy, DPOLICY_FORCE, 1); sb_start_intwrite(sbi->sb); @@ -1658,32 +1691,6 @@ skip: wake_up_discard_thread(sbi, false); } -void init_discard_policy(struct discard_policy *dpolicy, - int discard_type, unsigned int granularity) -{ - /* common policy */ - dpolicy->type = discard_type; - dpolicy->sync = true; - dpolicy->granularity = granularity; - - dpolicy->max_requests = DEF_MAX_DISCARD_REQUEST; - dpolicy->io_aware_gran = MAX_PLIST_NUM; - - if (discard_type == DPOLICY_BG) { - dpolicy->min_interval = DEF_MIN_DISCARD_ISSUE_TIME; - dpolicy->max_interval = DEF_MAX_DISCARD_ISSUE_TIME; - dpolicy->io_aware = true; - } else if (discard_type == DPOLICY_FORCE) { - dpolicy->min_interval = DEF_MIN_DISCARD_ISSUE_TIME; - dpolicy->max_interval = DEF_MAX_DISCARD_ISSUE_TIME; - dpolicy->io_aware = false; - } else if (discard_type == DPOLICY_FSTRIM) { - dpolicy->io_aware = false; - } else if (discard_type == DPOLICY_UMOUNT) { - dpolicy->io_aware = false; - } -} - static int create_discard_cmd_control(struct f2fs_sb_info *sbi) { dev_t dev = sbi->sb->s_bdev->bd_dev; @@ -2442,7 +2449,7 @@ int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct fstrim_range *range) start_block = START_BLOCK(sbi, start_segno); end_block = START_BLOCK(sbi, min(cur_segno, end_segno) + 1); - init_discard_policy(&dpolicy, DPOLICY_FSTRIM, cpc.trim_minlen); + __init_discard_policy(sbi, &dpolicy, DPOLICY_FSTRIM, cpc.trim_minlen); __issue_discard_cmd_range(sbi, &dpolicy, start_block, end_block); trimmed = __wait_discard_cmd_range(sbi, &dpolicy, start_block, end_block); -- 2.7.4