generic/299 w/ mode=lfs will cause long time latency, let's dump more information once we hit case.
CP merge: - Queued : 0 - Issued : 1 - Total : 1 - Cur time : 7565(ms) - Peak time : 7565(ms) F2FS-fs (vdc): checkpoint was blocked for 7565 ms, affecting 1 tasks CPU: 8 UID: 0 PID: 1614 Comm: f2fs_ckpt-253:3 Tainted: G O 6.16.0-rc3+ #406 PREEMPT(voluntary) Tainted: [O]=OOT_MODULE Call Trace: dump_stack_lvl+0x6e/0xa0 __checkpoint_and_complete_reqs+0x1a6/0x1d0 issue_checkpoint_thread+0x4b/0x140 kthread+0x10d/0x250 ret_from_fork+0x164/0x190 ret_from_fork_asm+0x1a/0x30 Cc: Jan Prusakowski <[email protected]> Signed-off-by: Chao Yu <[email protected]> --- fs/f2fs/checkpoint.c | 9 ++++++++- fs/f2fs/f2fs.h | 3 +++ 2 files changed, 11 insertions(+), 1 deletion(-) diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c index db3831f7f2f5..b0dcaa8dc40d 100644 --- a/fs/f2fs/checkpoint.c +++ b/fs/f2fs/checkpoint.c @@ -1788,8 +1788,15 @@ static void __checkpoint_and_complete_reqs(struct f2fs_sb_info *sbi) spin_lock(&cprc->stat_lock); cprc->cur_time = (unsigned int)div64_u64(sum_diff, count); - if (cprc->peak_time < cprc->cur_time) + if (cprc->peak_time < cprc->cur_time) { cprc->peak_time = cprc->cur_time; + + if (unlikely(cprc->peak_time >= CP_LONG_LATENCY_THRESHOLD)) { + f2fs_warn_ratelimited(sbi, "checkpoint was blocked for %u ms, affecting %llu tasks", + cprc->peak_time, count); + dump_stack(); + } + } spin_unlock(&cprc->stat_lock); } diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index 46d23c2c086c..3130ca6a4770 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -350,6 +350,9 @@ struct ckpt_req_control { unsigned int peak_time; /* peak wait time in msec until now */ }; +/* a time threshold that checkpoint was blocked for, unit: ms */ +#define CP_LONG_LATENCY_THRESHOLD 5000 + /* for the bitmap indicate blocks to be discarded */ struct discard_entry { struct list_head list; /* list head */ -- 2.49.0 _______________________________________________ Linux-f2fs-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
