* Re: [f2fs-dev] [PATCH v3] f2fs: fix long latency due to discard during umount [not found] <1585550730-1858-1-git-send-email-stummala@codeaurora.org> @ 2020-03-31 18:46 ` Jaegeuk Kim 2020-04-01 9:22 ` Sahitya Tummala 0 siblings, 1 reply; 7+ messages in thread From: Jaegeuk Kim @ 2020-03-31 18:46 UTC (permalink / raw) To: Sahitya Tummala; +Cc: linux-kernel, linux-f2fs-devel On 03/30, Sahitya Tummala wrote: > F2FS already has a default timeout of 5 secs for discards that > can be issued during umount, but it can take more than the 5 sec > timeout if the underlying UFS device queue is already full and there > are no more available free tags to be used. In that case, submit_bio() > will wait for the already queued discard requests to complete to get > a free tag, which can potentially take way more than 5 sec. > > Fix this by submitting the discard requests with REQ_NOWAIT > flags during umount. This will return -EAGAIN for UFS queue/tag full > scenario without waiting in the context of submit_bio(). The FS can > then handle these requests by retrying again within the stipulated > discard timeout period to avoid long latencies. Sorry, Sahitya, but, do we really need to do like this? How about just controlling # of outstanding discarding bios in __issue_discard_cmd()? > > Signed-off-by: Sahitya Tummala <stummala@codeaurora.org> > --- > v3: > -Handle the regression reported by Chao with v2. > -simplify the logic to split the dc with multiple bios incase any bio returns > EAGAIN and retry those new dc within 5 sec timeout. > > fs/f2fs/segment.c | 65 +++++++++++++++++++++++++++++++++++++++++++------------ > 1 file changed, 51 insertions(+), 14 deletions(-) > > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > index fb3e531..55d18c7 100644 > --- a/fs/f2fs/segment.c > +++ b/fs/f2fs/segment.c > @@ -1029,13 +1029,16 @@ static void f2fs_submit_discard_endio(struct bio *bio) > struct discard_cmd *dc = (struct discard_cmd *)bio->bi_private; > unsigned long flags; > > - dc->error = blk_status_to_errno(bio->bi_status); > - > spin_lock_irqsave(&dc->lock, flags); > + if (!dc->error) > + dc->error = blk_status_to_errno(bio->bi_status); > + > dc->bio_ref--; > - if (!dc->bio_ref && dc->state == D_SUBMIT) { > - dc->state = D_DONE; > - complete_all(&dc->wait); > + if (!dc->bio_ref) { > + if (dc->error || dc->state == D_SUBMIT) { > + dc->state = D_DONE; > + complete_all(&dc->wait); > + } > } > spin_unlock_irqrestore(&dc->lock, flags); > bio_put(bio); > @@ -1124,10 +1127,13 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info; > struct list_head *wait_list = (dpolicy->type == DPOLICY_FSTRIM) ? > &(dcc->fstrim_list) : &(dcc->wait_list); > - int flag = dpolicy->sync ? REQ_SYNC : 0; > + int flag; > block_t lstart, start, len, total_len; > int err = 0; > > + flag = dpolicy->sync ? REQ_SYNC : 0; > + flag |= dpolicy->type == DPOLICY_UMOUNT ? REQ_NOWAIT : 0; > + > if (dc->state != D_PREP) > return 0; > > @@ -1192,10 +1198,6 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > dc->bio_ref++; > spin_unlock_irqrestore(&dc->lock, flags); > > - atomic_inc(&dcc->queued_discard); > - dc->queued++; > - list_move_tail(&dc->list, wait_list); > - > /* sanity check on discard range */ > __check_sit_bitmap(sbi, lstart, lstart + len); > > @@ -1203,6 +1205,29 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > bio->bi_end_io = f2fs_submit_discard_endio; > bio->bi_opf |= flag; > submit_bio(bio); > + if (flag & REQ_NOWAIT) { > + if (dc->error == -EAGAIN) { > + spin_lock_irqsave(&dc->lock, flags); > + dc->len -= len; > + if (!dc->len) { > + dc->len = total_len; > + dc->state = D_PREP; > + reinit_completion(&dc->wait); > + } else { > + dcc->undiscard_blks -= total_len; > + if (dc->state == D_PARTIAL) > + dc->state = D_SUBMIT; > + } > + err = dc->error; > + dc->error = 0; > + spin_unlock_irqrestore(&dc->lock, flags); > + break; > + } > + } > + > + atomic_inc(&dcc->queued_discard); > + dc->queued++; > + list_move_tail(&dc->list, wait_list); > > atomic_inc(&dcc->issued_discard); > > @@ -1214,8 +1239,9 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > len = total_len; > } > > - if (!err && len) > - __update_discard_tree_range(sbi, bdev, lstart, start, len); > + if ((!err || err == -EAGAIN) && total_len && dc->start != start) > + __update_discard_tree_range(sbi, bdev, lstart, start, > + total_len); > return err; > } > > @@ -1470,12 +1496,15 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > struct list_head *pend_list; > struct discard_cmd *dc, *tmp; > struct blk_plug plug; > - int i, issued = 0; > + int i, err, issued = 0; > bool io_interrupted = false; > + bool retry; > > if (dpolicy->timeout != 0) > f2fs_update_time(sbi, dpolicy->timeout); > > +retry: > + retry = false; > for (i = MAX_PLIST_NUM - 1; i >= 0; i--) { > if (dpolicy->timeout != 0 && > f2fs_time_over(sbi, dpolicy->timeout)) > @@ -1509,7 +1538,12 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > break; > } > > - __submit_discard_cmd(sbi, dpolicy, dc, &issued); > + err = __submit_discard_cmd(sbi, dpolicy, dc, &issued); > + if (err == -EAGAIN) { > + congestion_wait(BLK_RW_ASYNC, > + DEFAULT_IO_TIMEOUT); > + retry = true; > + } > > if (issued >= dpolicy->max_requests) > break; > @@ -1522,6 +1556,9 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > break; > } > > + if (retry) > + goto retry; > + > if (!issued && io_interrupted) > issued = -1; > > -- > Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc. > Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project. _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [f2fs-dev] [PATCH v3] f2fs: fix long latency due to discard during umount 2020-03-31 18:46 ` [f2fs-dev] [PATCH v3] f2fs: fix long latency due to discard during umount Jaegeuk Kim @ 2020-04-01 9:22 ` Sahitya Tummala 2020-04-02 9:32 ` Chao Yu 2020-04-03 17:19 ` Jaegeuk Kim 0 siblings, 2 replies; 7+ messages in thread From: Sahitya Tummala @ 2020-04-01 9:22 UTC (permalink / raw) To: Jaegeuk Kim; +Cc: linux-kernel, linux-f2fs-devel Hi Jaegeuk, On Tue, Mar 31, 2020 at 11:46:55AM -0700, Jaegeuk Kim wrote: > On 03/30, Sahitya Tummala wrote: > > F2FS already has a default timeout of 5 secs for discards that > > can be issued during umount, but it can take more than the 5 sec > > timeout if the underlying UFS device queue is already full and there > > are no more available free tags to be used. In that case, submit_bio() > > will wait for the already queued discard requests to complete to get > > a free tag, which can potentially take way more than 5 sec. > > > > Fix this by submitting the discard requests with REQ_NOWAIT > > flags during umount. This will return -EAGAIN for UFS queue/tag full > > scenario without waiting in the context of submit_bio(). The FS can > > then handle these requests by retrying again within the stipulated > > discard timeout period to avoid long latencies. > > Sorry, Sahitya, but, do we really need to do like this? How about just > controlling # of outstanding discarding bios in __issue_discard_cmd()? Do you mean something like this? diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index 1a62b27..860dd43 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -1099,7 +1099,7 @@ static void __init_discard_policy(struct f2fs_sb_info *sbi, } else if (discard_type == DPOLICY_FSTRIM) { dpolicy->io_aware = false; } else if (discard_type == DPOLICY_UMOUNT) { - dpolicy->max_requests = UINT_MAX; + dpolicy->max_requests = 30; dpolicy->io_aware = false; /* we need to issue all to keep CP_TRIMMED_FLAG */ dpolicy->granularity = 1; @@ -1470,12 +1470,14 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, struct list_head *pend_list; struct discard_cmd *dc, *tmp; struct blk_plug plug; - int i, issued = 0; + int i, issued; bool io_interrupted = false; if (dpolicy->timeout != 0) f2fs_update_time(sbi, dpolicy->timeout); +retry: + issued = 0; for (i = MAX_PLIST_NUM - 1; i >= 0; i--) { if (dpolicy->timeout != 0 && f2fs_time_over(sbi, dpolicy->timeout)) @@ -1522,6 +1524,11 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, break; } + if (dpolicy->type == DPOLICY_UMOUNT && issued) { + __wait_all_discard_cmd(sbi, dpolicy); + goto retry; + } + if (!issued && io_interrupted) issued = -1; Thanks, > > > > > Signed-off-by: Sahitya Tummala <stummala@codeaurora.org> > > --- > > v3: > > -Handle the regression reported by Chao with v2. > > -simplify the logic to split the dc with multiple bios incase any bio returns > > EAGAIN and retry those new dc within 5 sec timeout. > > > > fs/f2fs/segment.c | 65 +++++++++++++++++++++++++++++++++++++++++++------------ > > 1 file changed, 51 insertions(+), 14 deletions(-) > > > > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > > index fb3e531..55d18c7 100644 > > --- a/fs/f2fs/segment.c > > +++ b/fs/f2fs/segment.c > > @@ -1029,13 +1029,16 @@ static void f2fs_submit_discard_endio(struct bio *bio) > > struct discard_cmd *dc = (struct discard_cmd *)bio->bi_private; > > unsigned long flags; > > > > - dc->error = blk_status_to_errno(bio->bi_status); > > - > > spin_lock_irqsave(&dc->lock, flags); > > + if (!dc->error) > > + dc->error = blk_status_to_errno(bio->bi_status); > > + > > dc->bio_ref--; > > - if (!dc->bio_ref && dc->state == D_SUBMIT) { > > - dc->state = D_DONE; > > - complete_all(&dc->wait); > > + if (!dc->bio_ref) { > > + if (dc->error || dc->state == D_SUBMIT) { > > + dc->state = D_DONE; > > + complete_all(&dc->wait); > > + } > > } > > spin_unlock_irqrestore(&dc->lock, flags); > > bio_put(bio); > > @@ -1124,10 +1127,13 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > > struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info; > > struct list_head *wait_list = (dpolicy->type == DPOLICY_FSTRIM) ? > > &(dcc->fstrim_list) : &(dcc->wait_list); > > - int flag = dpolicy->sync ? REQ_SYNC : 0; > > + int flag; > > block_t lstart, start, len, total_len; > > int err = 0; > > > > + flag = dpolicy->sync ? REQ_SYNC : 0; > > + flag |= dpolicy->type == DPOLICY_UMOUNT ? REQ_NOWAIT : 0; > > + > > if (dc->state != D_PREP) > > return 0; > > > > @@ -1192,10 +1198,6 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > > dc->bio_ref++; > > spin_unlock_irqrestore(&dc->lock, flags); > > > > - atomic_inc(&dcc->queued_discard); > > - dc->queued++; > > - list_move_tail(&dc->list, wait_list); > > - > > /* sanity check on discard range */ > > __check_sit_bitmap(sbi, lstart, lstart + len); > > > > @@ -1203,6 +1205,29 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > > bio->bi_end_io = f2fs_submit_discard_endio; > > bio->bi_opf |= flag; > > submit_bio(bio); > > + if (flag & REQ_NOWAIT) { > > + if (dc->error == -EAGAIN) { > > + spin_lock_irqsave(&dc->lock, flags); > > + dc->len -= len; > > + if (!dc->len) { > > + dc->len = total_len; > > + dc->state = D_PREP; > > + reinit_completion(&dc->wait); > > + } else { > > + dcc->undiscard_blks -= total_len; > > + if (dc->state == D_PARTIAL) > > + dc->state = D_SUBMIT; > > + } > > + err = dc->error; > > + dc->error = 0; > > + spin_unlock_irqrestore(&dc->lock, flags); > > + break; > > + } > > + } > > + > > + atomic_inc(&dcc->queued_discard); > > + dc->queued++; > > + list_move_tail(&dc->list, wait_list); > > > > atomic_inc(&dcc->issued_discard); > > > > @@ -1214,8 +1239,9 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > > len = total_len; > > } > > > > - if (!err && len) > > - __update_discard_tree_range(sbi, bdev, lstart, start, len); > > + if ((!err || err == -EAGAIN) && total_len && dc->start != start) > > + __update_discard_tree_range(sbi, bdev, lstart, start, > > + total_len); > > return err; > > } > > > > @@ -1470,12 +1496,15 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > struct list_head *pend_list; > > struct discard_cmd *dc, *tmp; > > struct blk_plug plug; > > - int i, issued = 0; > > + int i, err, issued = 0; > > bool io_interrupted = false; > > + bool retry; > > > > if (dpolicy->timeout != 0) > > f2fs_update_time(sbi, dpolicy->timeout); > > > > +retry: > > + retry = false; > > for (i = MAX_PLIST_NUM - 1; i >= 0; i--) { > > if (dpolicy->timeout != 0 && > > f2fs_time_over(sbi, dpolicy->timeout)) > > @@ -1509,7 +1538,12 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > break; > > } > > > > - __submit_discard_cmd(sbi, dpolicy, dc, &issued); > > + err = __submit_discard_cmd(sbi, dpolicy, dc, &issued); > > + if (err == -EAGAIN) { > > + congestion_wait(BLK_RW_ASYNC, > > + DEFAULT_IO_TIMEOUT); > > + retry = true; > > + } > > > > if (issued >= dpolicy->max_requests) > > break; > > @@ -1522,6 +1556,9 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > break; > > } > > > > + if (retry) > > + goto retry; > > + > > if (!issued && io_interrupted) > > issued = -1; > > > > -- > > Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc. > > Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project. -- -- Sent by a consultant of the Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum. _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel ^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [f2fs-dev] [PATCH v3] f2fs: fix long latency due to discard during umount 2020-04-01 9:22 ` Sahitya Tummala @ 2020-04-02 9:32 ` Chao Yu 2020-04-03 17:19 ` Jaegeuk Kim 1 sibling, 0 replies; 7+ messages in thread From: Chao Yu @ 2020-04-02 9:32 UTC (permalink / raw) To: Sahitya Tummala, Jaegeuk Kim; +Cc: linux-kernel, linux-f2fs-devel On 2020/4/1 17:22, Sahitya Tummala wrote: > Hi Jaegeuk, > > On Tue, Mar 31, 2020 at 11:46:55AM -0700, Jaegeuk Kim wrote: >> On 03/30, Sahitya Tummala wrote: >>> F2FS already has a default timeout of 5 secs for discards that >>> can be issued during umount, but it can take more than the 5 sec >>> timeout if the underlying UFS device queue is already full and there >>> are no more available free tags to be used. In that case, submit_bio() >>> will wait for the already queued discard requests to complete to get >>> a free tag, which can potentially take way more than 5 sec. >>> >>> Fix this by submitting the discard requests with REQ_NOWAIT >>> flags during umount. This will return -EAGAIN for UFS queue/tag full >>> scenario without waiting in the context of submit_bio(). The FS can >>> then handle these requests by retrying again within the stipulated >>> discard timeout period to avoid long latencies. >> >> Sorry, Sahitya, but, do we really need to do like this? How about just >> controlling # of outstanding discarding bios in __issue_discard_cmd()? > > Do you mean something like this? > > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > index 1a62b27..860dd43 100644 > --- a/fs/f2fs/segment.c > +++ b/fs/f2fs/segment.c > @@ -1099,7 +1099,7 @@ static void __init_discard_policy(struct f2fs_sb_info *sbi, > } else if (discard_type == DPOLICY_FSTRIM) { > dpolicy->io_aware = false; > } else if (discard_type == DPOLICY_UMOUNT) { > - dpolicy->max_requests = UINT_MAX; > + dpolicy->max_requests = 30; 8 or 16? It looks more simple than previous implementation. Thanks, > dpolicy->io_aware = false; > /* we need to issue all to keep CP_TRIMMED_FLAG */ > dpolicy->granularity = 1; > @@ -1470,12 +1470,14 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > struct list_head *pend_list; > struct discard_cmd *dc, *tmp; > struct blk_plug plug; > - int i, issued = 0; > + int i, issued; > bool io_interrupted = false; > > if (dpolicy->timeout != 0) > f2fs_update_time(sbi, dpolicy->timeout); > > +retry: > + issued = 0; > for (i = MAX_PLIST_NUM - 1; i >= 0; i--) { > if (dpolicy->timeout != 0 && > f2fs_time_over(sbi, dpolicy->timeout)) > @@ -1522,6 +1524,11 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > break; > } > > + if (dpolicy->type == DPOLICY_UMOUNT && issued) { > + __wait_all_discard_cmd(sbi, dpolicy); > + goto retry; > + } > + > if (!issued && io_interrupted) > issued = -1; > > Thanks, > >> >>> >>> Signed-off-by: Sahitya Tummala <stummala@codeaurora.org> >>> --- >>> v3: >>> -Handle the regression reported by Chao with v2. >>> -simplify the logic to split the dc with multiple bios incase any bio returns >>> EAGAIN and retry those new dc within 5 sec timeout. >>> >>> fs/f2fs/segment.c | 65 +++++++++++++++++++++++++++++++++++++++++++------------ >>> 1 file changed, 51 insertions(+), 14 deletions(-) >>> >>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c >>> index fb3e531..55d18c7 100644 >>> --- a/fs/f2fs/segment.c >>> +++ b/fs/f2fs/segment.c >>> @@ -1029,13 +1029,16 @@ static void f2fs_submit_discard_endio(struct bio *bio) >>> struct discard_cmd *dc = (struct discard_cmd *)bio->bi_private; >>> unsigned long flags; >>> >>> - dc->error = blk_status_to_errno(bio->bi_status); >>> - >>> spin_lock_irqsave(&dc->lock, flags); >>> + if (!dc->error) >>> + dc->error = blk_status_to_errno(bio->bi_status); >>> + >>> dc->bio_ref--; >>> - if (!dc->bio_ref && dc->state == D_SUBMIT) { >>> - dc->state = D_DONE; >>> - complete_all(&dc->wait); >>> + if (!dc->bio_ref) { >>> + if (dc->error || dc->state == D_SUBMIT) { >>> + dc->state = D_DONE; >>> + complete_all(&dc->wait); >>> + } >>> } >>> spin_unlock_irqrestore(&dc->lock, flags); >>> bio_put(bio); >>> @@ -1124,10 +1127,13 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, >>> struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info; >>> struct list_head *wait_list = (dpolicy->type == DPOLICY_FSTRIM) ? >>> &(dcc->fstrim_list) : &(dcc->wait_list); >>> - int flag = dpolicy->sync ? REQ_SYNC : 0; >>> + int flag; >>> block_t lstart, start, len, total_len; >>> int err = 0; >>> >>> + flag = dpolicy->sync ? REQ_SYNC : 0; >>> + flag |= dpolicy->type == DPOLICY_UMOUNT ? REQ_NOWAIT : 0; >>> + >>> if (dc->state != D_PREP) >>> return 0; >>> >>> @@ -1192,10 +1198,6 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, >>> dc->bio_ref++; >>> spin_unlock_irqrestore(&dc->lock, flags); >>> >>> - atomic_inc(&dcc->queued_discard); >>> - dc->queued++; >>> - list_move_tail(&dc->list, wait_list); >>> - >>> /* sanity check on discard range */ >>> __check_sit_bitmap(sbi, lstart, lstart + len); >>> >>> @@ -1203,6 +1205,29 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, >>> bio->bi_end_io = f2fs_submit_discard_endio; >>> bio->bi_opf |= flag; >>> submit_bio(bio); >>> + if (flag & REQ_NOWAIT) { >>> + if (dc->error == -EAGAIN) { >>> + spin_lock_irqsave(&dc->lock, flags); >>> + dc->len -= len; >>> + if (!dc->len) { >>> + dc->len = total_len; >>> + dc->state = D_PREP; >>> + reinit_completion(&dc->wait); >>> + } else { >>> + dcc->undiscard_blks -= total_len; >>> + if (dc->state == D_PARTIAL) >>> + dc->state = D_SUBMIT; >>> + } >>> + err = dc->error; >>> + dc->error = 0; >>> + spin_unlock_irqrestore(&dc->lock, flags); >>> + break; >>> + } >>> + } >>> + >>> + atomic_inc(&dcc->queued_discard); >>> + dc->queued++; >>> + list_move_tail(&dc->list, wait_list); >>> >>> atomic_inc(&dcc->issued_discard); >>> >>> @@ -1214,8 +1239,9 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, >>> len = total_len; >>> } >>> >>> - if (!err && len) >>> - __update_discard_tree_range(sbi, bdev, lstart, start, len); >>> + if ((!err || err == -EAGAIN) && total_len && dc->start != start) >>> + __update_discard_tree_range(sbi, bdev, lstart, start, >>> + total_len); >>> return err; >>> } >>> >>> @@ -1470,12 +1496,15 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, >>> struct list_head *pend_list; >>> struct discard_cmd *dc, *tmp; >>> struct blk_plug plug; >>> - int i, issued = 0; >>> + int i, err, issued = 0; >>> bool io_interrupted = false; >>> + bool retry; >>> >>> if (dpolicy->timeout != 0) >>> f2fs_update_time(sbi, dpolicy->timeout); >>> >>> +retry: >>> + retry = false; >>> for (i = MAX_PLIST_NUM - 1; i >= 0; i--) { >>> if (dpolicy->timeout != 0 && >>> f2fs_time_over(sbi, dpolicy->timeout)) >>> @@ -1509,7 +1538,12 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, >>> break; >>> } >>> >>> - __submit_discard_cmd(sbi, dpolicy, dc, &issued); >>> + err = __submit_discard_cmd(sbi, dpolicy, dc, &issued); >>> + if (err == -EAGAIN) { >>> + congestion_wait(BLK_RW_ASYNC, >>> + DEFAULT_IO_TIMEOUT); >>> + retry = true; >>> + } >>> >>> if (issued >= dpolicy->max_requests) >>> break; >>> @@ -1522,6 +1556,9 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, >>> break; >>> } >>> >>> + if (retry) >>> + goto retry; >>> + >>> if (!issued && io_interrupted) >>> issued = -1; >>> >>> -- >>> Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc. >>> Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project. > _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [f2fs-dev] [PATCH v3] f2fs: fix long latency due to discard during umount 2020-04-01 9:22 ` Sahitya Tummala 2020-04-02 9:32 ` Chao Yu @ 2020-04-03 17:19 ` Jaegeuk Kim [not found] ` <20200408090024.GC20234@codeaurora.org> 1 sibling, 1 reply; 7+ messages in thread From: Jaegeuk Kim @ 2020-04-03 17:19 UTC (permalink / raw) To: Sahitya Tummala; +Cc: linux-kernel, linux-f2fs-devel On 04/01, Sahitya Tummala wrote: > Hi Jaegeuk, > > On Tue, Mar 31, 2020 at 11:46:55AM -0700, Jaegeuk Kim wrote: > > On 03/30, Sahitya Tummala wrote: > > > F2FS already has a default timeout of 5 secs for discards that > > > can be issued during umount, but it can take more than the 5 sec > > > timeout if the underlying UFS device queue is already full and there > > > are no more available free tags to be used. In that case, submit_bio() > > > will wait for the already queued discard requests to complete to get > > > a free tag, which can potentially take way more than 5 sec. > > > > > > Fix this by submitting the discard requests with REQ_NOWAIT > > > flags during umount. This will return -EAGAIN for UFS queue/tag full > > > scenario without waiting in the context of submit_bio(). The FS can > > > then handle these requests by retrying again within the stipulated > > > discard timeout period to avoid long latencies. > > > > Sorry, Sahitya, but, do we really need to do like this? How about just > > controlling # of outstanding discarding bios in __issue_discard_cmd()? > > Do you mean something like this? > > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > index 1a62b27..860dd43 100644 > --- a/fs/f2fs/segment.c > +++ b/fs/f2fs/segment.c > @@ -1099,7 +1099,7 @@ static void __init_discard_policy(struct f2fs_sb_info *sbi, > } else if (discard_type == DPOLICY_FSTRIM) { > dpolicy->io_aware = false; > } else if (discard_type == DPOLICY_UMOUNT) { > - dpolicy->max_requests = UINT_MAX; > + dpolicy->max_requests = 30; Can we use max queue depth of the block device? > dpolicy->io_aware = false; > /* we need to issue all to keep CP_TRIMMED_FLAG */ > dpolicy->granularity = 1; > @@ -1470,12 +1470,14 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > struct list_head *pend_list; > struct discard_cmd *dc, *tmp; > struct blk_plug plug; > - int i, issued = 0; > + int i, issued; > bool io_interrupted = false; > > if (dpolicy->timeout != 0) > f2fs_update_time(sbi, dpolicy->timeout); > > +retry: > + issued = 0; > for (i = MAX_PLIST_NUM - 1; i >= 0; i--) { > if (dpolicy->timeout != 0 && > f2fs_time_over(sbi, dpolicy->timeout)) > @@ -1522,6 +1524,11 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > break; > } > > + if (dpolicy->type == DPOLICY_UMOUNT && issued) { > + __wait_all_discard_cmd(sbi, dpolicy); > + goto retry; > + } > + > if (!issued && io_interrupted) > issued = -1; > > Thanks, > > > > > > > > > Signed-off-by: Sahitya Tummala <stummala@codeaurora.org> > > > --- > > > v3: > > > -Handle the regression reported by Chao with v2. > > > -simplify the logic to split the dc with multiple bios incase any bio returns > > > EAGAIN and retry those new dc within 5 sec timeout. > > > > > > fs/f2fs/segment.c | 65 +++++++++++++++++++++++++++++++++++++++++++------------ > > > 1 file changed, 51 insertions(+), 14 deletions(-) > > > > > > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > > > index fb3e531..55d18c7 100644 > > > --- a/fs/f2fs/segment.c > > > +++ b/fs/f2fs/segment.c > > > @@ -1029,13 +1029,16 @@ static void f2fs_submit_discard_endio(struct bio *bio) > > > struct discard_cmd *dc = (struct discard_cmd *)bio->bi_private; > > > unsigned long flags; > > > > > > - dc->error = blk_status_to_errno(bio->bi_status); > > > - > > > spin_lock_irqsave(&dc->lock, flags); > > > + if (!dc->error) > > > + dc->error = blk_status_to_errno(bio->bi_status); > > > + > > > dc->bio_ref--; > > > - if (!dc->bio_ref && dc->state == D_SUBMIT) { > > > - dc->state = D_DONE; > > > - complete_all(&dc->wait); > > > + if (!dc->bio_ref) { > > > + if (dc->error || dc->state == D_SUBMIT) { > > > + dc->state = D_DONE; > > > + complete_all(&dc->wait); > > > + } > > > } > > > spin_unlock_irqrestore(&dc->lock, flags); > > > bio_put(bio); > > > @@ -1124,10 +1127,13 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > > > struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info; > > > struct list_head *wait_list = (dpolicy->type == DPOLICY_FSTRIM) ? > > > &(dcc->fstrim_list) : &(dcc->wait_list); > > > - int flag = dpolicy->sync ? REQ_SYNC : 0; > > > + int flag; > > > block_t lstart, start, len, total_len; > > > int err = 0; > > > > > > + flag = dpolicy->sync ? REQ_SYNC : 0; > > > + flag |= dpolicy->type == DPOLICY_UMOUNT ? REQ_NOWAIT : 0; > > > + > > > if (dc->state != D_PREP) > > > return 0; > > > > > > @@ -1192,10 +1198,6 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > > > dc->bio_ref++; > > > spin_unlock_irqrestore(&dc->lock, flags); > > > > > > - atomic_inc(&dcc->queued_discard); > > > - dc->queued++; > > > - list_move_tail(&dc->list, wait_list); > > > - > > > /* sanity check on discard range */ > > > __check_sit_bitmap(sbi, lstart, lstart + len); > > > > > > @@ -1203,6 +1205,29 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > > > bio->bi_end_io = f2fs_submit_discard_endio; > > > bio->bi_opf |= flag; > > > submit_bio(bio); > > > + if (flag & REQ_NOWAIT) { > > > + if (dc->error == -EAGAIN) { > > > + spin_lock_irqsave(&dc->lock, flags); > > > + dc->len -= len; > > > + if (!dc->len) { > > > + dc->len = total_len; > > > + dc->state = D_PREP; > > > + reinit_completion(&dc->wait); > > > + } else { > > > + dcc->undiscard_blks -= total_len; > > > + if (dc->state == D_PARTIAL) > > > + dc->state = D_SUBMIT; > > > + } > > > + err = dc->error; > > > + dc->error = 0; > > > + spin_unlock_irqrestore(&dc->lock, flags); > > > + break; > > > + } > > > + } > > > + > > > + atomic_inc(&dcc->queued_discard); > > > + dc->queued++; > > > + list_move_tail(&dc->list, wait_list); > > > > > > atomic_inc(&dcc->issued_discard); > > > > > > @@ -1214,8 +1239,9 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > > > len = total_len; > > > } > > > > > > - if (!err && len) > > > - __update_discard_tree_range(sbi, bdev, lstart, start, len); > > > + if ((!err || err == -EAGAIN) && total_len && dc->start != start) > > > + __update_discard_tree_range(sbi, bdev, lstart, start, > > > + total_len); > > > return err; > > > } > > > > > > @@ -1470,12 +1496,15 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > > struct list_head *pend_list; > > > struct discard_cmd *dc, *tmp; > > > struct blk_plug plug; > > > - int i, issued = 0; > > > + int i, err, issued = 0; > > > bool io_interrupted = false; > > > + bool retry; > > > > > > if (dpolicy->timeout != 0) > > > f2fs_update_time(sbi, dpolicy->timeout); > > > > > > +retry: > > > + retry = false; > > > for (i = MAX_PLIST_NUM - 1; i >= 0; i--) { > > > if (dpolicy->timeout != 0 && > > > f2fs_time_over(sbi, dpolicy->timeout)) > > > @@ -1509,7 +1538,12 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > > break; > > > } > > > > > > - __submit_discard_cmd(sbi, dpolicy, dc, &issued); > > > + err = __submit_discard_cmd(sbi, dpolicy, dc, &issued); > > > + if (err == -EAGAIN) { > > > + congestion_wait(BLK_RW_ASYNC, > > > + DEFAULT_IO_TIMEOUT); > > > + retry = true; > > > + } > > > > > > if (issued >= dpolicy->max_requests) > > > break; > > > @@ -1522,6 +1556,9 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > > break; > > > } > > > > > > + if (retry) > > > + goto retry; > > > + > > > if (!issued && io_interrupted) > > > issued = -1; > > > > > > -- > > > Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc. > > > Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project. > > -- > -- > Sent by a consultant of the Qualcomm Innovation Center, Inc. > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum. _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel ^ permalink raw reply [flat|nested] 7+ messages in thread
[parent not found: <20200408090024.GC20234@codeaurora.org>]
* Re: [f2fs-dev] [PATCH v3] f2fs: fix long latency due to discard during umount [not found] ` <20200408090024.GC20234@codeaurora.org> @ 2020-04-09 2:29 ` Jaegeuk Kim [not found] ` <20200409114756.GD20234@codeaurora.org> 0 siblings, 1 reply; 7+ messages in thread From: Jaegeuk Kim @ 2020-04-09 2:29 UTC (permalink / raw) To: Sahitya Tummala; +Cc: linux-kernel, linux-f2fs-devel On 04/08, Sahitya Tummala wrote: > Hi Jaegeuk, > > On Fri, Apr 03, 2020 at 10:19:43AM -0700, Jaegeuk Kim wrote: > > On 04/01, Sahitya Tummala wrote: > > > Hi Jaegeuk, > > > > > > On Tue, Mar 31, 2020 at 11:46:55AM -0700, Jaegeuk Kim wrote: > > > > On 03/30, Sahitya Tummala wrote: > > > > > F2FS already has a default timeout of 5 secs for discards that > > > > > can be issued during umount, but it can take more than the 5 sec > > > > > timeout if the underlying UFS device queue is already full and there > > > > > are no more available free tags to be used. In that case, submit_bio() > > > > > will wait for the already queued discard requests to complete to get > > > > > a free tag, which can potentially take way more than 5 sec. > > > > > > > > > > Fix this by submitting the discard requests with REQ_NOWAIT > > > > > flags during umount. This will return -EAGAIN for UFS queue/tag full > > > > > scenario without waiting in the context of submit_bio(). The FS can > > > > > then handle these requests by retrying again within the stipulated > > > > > discard timeout period to avoid long latencies. > > > > > > > > Sorry, Sahitya, but, do we really need to do like this? How about just > > > > controlling # of outstanding discarding bios in __issue_discard_cmd()? > > > > > > Do you mean something like this? > > > > > > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > > > index 1a62b27..860dd43 100644 > > > --- a/fs/f2fs/segment.c > > > +++ b/fs/f2fs/segment.c > > > @@ -1099,7 +1099,7 @@ static void __init_discard_policy(struct f2fs_sb_info *sbi, > > > } else if (discard_type == DPOLICY_FSTRIM) { > > > dpolicy->io_aware = false; > > > } else if (discard_type == DPOLICY_UMOUNT) { > > > - dpolicy->max_requests = UINT_MAX; > > > + dpolicy->max_requests = 30; > > > > Can we use max queue depth of the block device? > > I think it should be limited to 8 or 16 as Chao suggested, so that we can have > better control on the given timeout value? Thoughts? Where is 8 or 16 coming from? What about SSD? Sorry, it's unclear to me. > > Thanks, > > > > > > dpolicy->io_aware = false; > > > /* we need to issue all to keep CP_TRIMMED_FLAG */ > > > dpolicy->granularity = 1; > > > @@ -1470,12 +1470,14 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > > struct list_head *pend_list; > > > struct discard_cmd *dc, *tmp; > > > struct blk_plug plug; > > > - int i, issued = 0; > > > + int i, issued; > > > bool io_interrupted = false; > > > > > > if (dpolicy->timeout != 0) > > > f2fs_update_time(sbi, dpolicy->timeout); > > > > > > +retry: > > > + issued = 0; > > > for (i = MAX_PLIST_NUM - 1; i >= 0; i--) { > > > if (dpolicy->timeout != 0 && > > > f2fs_time_over(sbi, dpolicy->timeout)) > > > @@ -1522,6 +1524,11 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > > break; > > > } > > > > > > + if (dpolicy->type == DPOLICY_UMOUNT && issued) { > > > + __wait_all_discard_cmd(sbi, dpolicy); > > > + goto retry; > > > + } > > > + > > > if (!issued && io_interrupted) > > > issued = -1; > > > > > > Thanks, > > > > > > > > > > > > > > > > > Signed-off-by: Sahitya Tummala <stummala@codeaurora.org> > > > > > --- > > > > > v3: > > > > > -Handle the regression reported by Chao with v2. > > > > > -simplify the logic to split the dc with multiple bios incase any bio returns > > > > > EAGAIN and retry those new dc within 5 sec timeout. > > > > > > > > > > fs/f2fs/segment.c | 65 +++++++++++++++++++++++++++++++++++++++++++------------ > > > > > 1 file changed, 51 insertions(+), 14 deletions(-) > > > > > > > > > > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > > > > > index fb3e531..55d18c7 100644 > > > > > --- a/fs/f2fs/segment.c > > > > > +++ b/fs/f2fs/segment.c > > > > > @@ -1029,13 +1029,16 @@ static void f2fs_submit_discard_endio(struct bio *bio) > > > > > struct discard_cmd *dc = (struct discard_cmd *)bio->bi_private; > > > > > unsigned long flags; > > > > > > > > > > - dc->error = blk_status_to_errno(bio->bi_status); > > > > > - > > > > > spin_lock_irqsave(&dc->lock, flags); > > > > > + if (!dc->error) > > > > > + dc->error = blk_status_to_errno(bio->bi_status); > > > > > + > > > > > dc->bio_ref--; > > > > > - if (!dc->bio_ref && dc->state == D_SUBMIT) { > > > > > - dc->state = D_DONE; > > > > > - complete_all(&dc->wait); > > > > > + if (!dc->bio_ref) { > > > > > + if (dc->error || dc->state == D_SUBMIT) { > > > > > + dc->state = D_DONE; > > > > > + complete_all(&dc->wait); > > > > > + } > > > > > } > > > > > spin_unlock_irqrestore(&dc->lock, flags); > > > > > bio_put(bio); > > > > > @@ -1124,10 +1127,13 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > > > > > struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info; > > > > > struct list_head *wait_list = (dpolicy->type == DPOLICY_FSTRIM) ? > > > > > &(dcc->fstrim_list) : &(dcc->wait_list); > > > > > - int flag = dpolicy->sync ? REQ_SYNC : 0; > > > > > + int flag; > > > > > block_t lstart, start, len, total_len; > > > > > int err = 0; > > > > > > > > > > + flag = dpolicy->sync ? REQ_SYNC : 0; > > > > > + flag |= dpolicy->type == DPOLICY_UMOUNT ? REQ_NOWAIT : 0; > > > > > + > > > > > if (dc->state != D_PREP) > > > > > return 0; > > > > > > > > > > @@ -1192,10 +1198,6 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > > > > > dc->bio_ref++; > > > > > spin_unlock_irqrestore(&dc->lock, flags); > > > > > > > > > > - atomic_inc(&dcc->queued_discard); > > > > > - dc->queued++; > > > > > - list_move_tail(&dc->list, wait_list); > > > > > - > > > > > /* sanity check on discard range */ > > > > > __check_sit_bitmap(sbi, lstart, lstart + len); > > > > > > > > > > @@ -1203,6 +1205,29 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > > > > > bio->bi_end_io = f2fs_submit_discard_endio; > > > > > bio->bi_opf |= flag; > > > > > submit_bio(bio); > > > > > + if (flag & REQ_NOWAIT) { > > > > > + if (dc->error == -EAGAIN) { > > > > > + spin_lock_irqsave(&dc->lock, flags); > > > > > + dc->len -= len; > > > > > + if (!dc->len) { > > > > > + dc->len = total_len; > > > > > + dc->state = D_PREP; > > > > > + reinit_completion(&dc->wait); > > > > > + } else { > > > > > + dcc->undiscard_blks -= total_len; > > > > > + if (dc->state == D_PARTIAL) > > > > > + dc->state = D_SUBMIT; > > > > > + } > > > > > + err = dc->error; > > > > > + dc->error = 0; > > > > > + spin_unlock_irqrestore(&dc->lock, flags); > > > > > + break; > > > > > + } > > > > > + } > > > > > + > > > > > + atomic_inc(&dcc->queued_discard); > > > > > + dc->queued++; > > > > > + list_move_tail(&dc->list, wait_list); > > > > > > > > > > atomic_inc(&dcc->issued_discard); > > > > > > > > > > @@ -1214,8 +1239,9 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > > > > > len = total_len; > > > > > } > > > > > > > > > > - if (!err && len) > > > > > - __update_discard_tree_range(sbi, bdev, lstart, start, len); > > > > > + if ((!err || err == -EAGAIN) && total_len && dc->start != start) > > > > > + __update_discard_tree_range(sbi, bdev, lstart, start, > > > > > + total_len); > > > > > return err; > > > > > } > > > > > > > > > > @@ -1470,12 +1496,15 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > > > > struct list_head *pend_list; > > > > > struct discard_cmd *dc, *tmp; > > > > > struct blk_plug plug; > > > > > - int i, issued = 0; > > > > > + int i, err, issued = 0; > > > > > bool io_interrupted = false; > > > > > + bool retry; > > > > > > > > > > if (dpolicy->timeout != 0) > > > > > f2fs_update_time(sbi, dpolicy->timeout); > > > > > > > > > > +retry: > > > > > + retry = false; > > > > > for (i = MAX_PLIST_NUM - 1; i >= 0; i--) { > > > > > if (dpolicy->timeout != 0 && > > > > > f2fs_time_over(sbi, dpolicy->timeout)) > > > > > @@ -1509,7 +1538,12 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > > > > break; > > > > > } > > > > > > > > > > - __submit_discard_cmd(sbi, dpolicy, dc, &issued); > > > > > + err = __submit_discard_cmd(sbi, dpolicy, dc, &issued); > > > > > + if (err == -EAGAIN) { > > > > > + congestion_wait(BLK_RW_ASYNC, > > > > > + DEFAULT_IO_TIMEOUT); > > > > > + retry = true; > > > > > + } > > > > > > > > > > if (issued >= dpolicy->max_requests) > > > > > break; > > > > > @@ -1522,6 +1556,9 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > > > > break; > > > > > } > > > > > > > > > > + if (retry) > > > > > + goto retry; > > > > > + > > > > > if (!issued && io_interrupted) > > > > > issued = -1; > > > > > > > > > > -- > > > > > Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc. > > > > > Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project. > > > > > > -- > > > -- > > > Sent by a consultant of the Qualcomm Innovation Center, Inc. > > > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum. > > -- > -- > Sent by a consultant of the Qualcomm Innovation Center, Inc. > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum. _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel ^ permalink raw reply [flat|nested] 7+ messages in thread
[parent not found: <20200409114756.GD20234@codeaurora.org>]
* Re: [f2fs-dev] [PATCH v3] f2fs: fix long latency due to discard during umount [not found] ` <20200409114756.GD20234@codeaurora.org> @ 2020-04-13 16:52 ` Jaegeuk Kim 2020-04-14 17:45 ` Jaegeuk Kim 0 siblings, 1 reply; 7+ messages in thread From: Jaegeuk Kim @ 2020-04-13 16:52 UTC (permalink / raw) To: Sahitya Tummala; +Cc: linux-kernel, linux-f2fs-devel On 04/09, Sahitya Tummala wrote: > On Wed, Apr 08, 2020 at 07:29:28PM -0700, Jaegeuk Kim wrote: > > On 04/08, Sahitya Tummala wrote: > > > Hi Jaegeuk, > > > > > > On Fri, Apr 03, 2020 at 10:19:43AM -0700, Jaegeuk Kim wrote: > > > > On 04/01, Sahitya Tummala wrote: > > > > > Hi Jaegeuk, > > > > > > > > > > On Tue, Mar 31, 2020 at 11:46:55AM -0700, Jaegeuk Kim wrote: > > > > > > On 03/30, Sahitya Tummala wrote: > > > > > > > F2FS already has a default timeout of 5 secs for discards that > > > > > > > can be issued during umount, but it can take more than the 5 sec > > > > > > > timeout if the underlying UFS device queue is already full and there > > > > > > > are no more available free tags to be used. In that case, submit_bio() > > > > > > > will wait for the already queued discard requests to complete to get > > > > > > > a free tag, which can potentially take way more than 5 sec. > > > > > > > > > > > > > > Fix this by submitting the discard requests with REQ_NOWAIT > > > > > > > flags during umount. This will return -EAGAIN for UFS queue/tag full > > > > > > > scenario without waiting in the context of submit_bio(). The FS can > > > > > > > then handle these requests by retrying again within the stipulated > > > > > > > discard timeout period to avoid long latencies. > > > > > > > > > > > > Sorry, Sahitya, but, do we really need to do like this? How about just > > > > > > controlling # of outstanding discarding bios in __issue_discard_cmd()? > > > > > > > > > > Do you mean something like this? > > > > > > > > > > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > > > > > index 1a62b27..860dd43 100644 > > > > > --- a/fs/f2fs/segment.c > > > > > +++ b/fs/f2fs/segment.c > > > > > @@ -1099,7 +1099,7 @@ static void __init_discard_policy(struct f2fs_sb_info *sbi, > > > > > } else if (discard_type == DPOLICY_FSTRIM) { > > > > > dpolicy->io_aware = false; > > > > > } else if (discard_type == DPOLICY_UMOUNT) { > > > > > - dpolicy->max_requests = UINT_MAX; > > > > > + dpolicy->max_requests = 30; > > > > > > > > Can we use max queue depth of the block device? > > > > > > I think it should be limited to 8 or 16 as Chao suggested, so that we can have > > > better control on the given timeout value? Thoughts? > > > > Where is 8 or 16 coming from? What about SSD? Sorry, it's unclear to me. > > With this patch we now wait for a batch of discard requests in __issue_discard_cmd() > with a upper timeout of 5 sec. So, I thought that having a smaller batch of > discard requests would help us to avoid queuing more requests and end up waiting > for more time in __wait_all_discard_cmd(). Today we have DEF_MAX_DISCARD_REQUEST > as 8 for default max discard requests. If it too less, may be for umount > we can use 16 instead. But the idea is to avoid more wait time. Ok, then, it seems we can just remove this line to use dpolicy->max_requests, and retry issuing all the discard commands like below. Later, I thnk it'd be fine to tune the max_requests based on bd_queue->queue_depth. > > If you would like to propose to use max queue depth, we can get it from bdev as > sbi->sb->s_bdev->bd_queue->queue_depth. Is it okay to use it in our FS? or you > think it should be hardcoded to 32 (as most UFS/eMMC devices will have this as > its queue depth)? Please let me know. > > Thanks, > > > > > > > > > Thanks, > > > > > > > > > > > > dpolicy->io_aware = false; > > > > > /* we need to issue all to keep CP_TRIMMED_FLAG */ > > > > > dpolicy->granularity = 1; > > > > > @@ -1470,12 +1470,14 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > > > > struct list_head *pend_list; > > > > > struct discard_cmd *dc, *tmp; > > > > > struct blk_plug plug; > > > > > - int i, issued = 0; > > > > > + int i, issued; > > > > > bool io_interrupted = false; > > > > > > > > > > if (dpolicy->timeout != 0) > > > > > f2fs_update_time(sbi, dpolicy->timeout); > > > > > > > > > > +retry: > > > > > + issued = 0; > > > > > for (i = MAX_PLIST_NUM - 1; i >= 0; i--) { > > > > > if (dpolicy->timeout != 0 && > > > > > f2fs_time_over(sbi, dpolicy->timeout)) > > > > > @@ -1522,6 +1524,11 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > > > > break; > > > > > } > > > > > > > > > > + if (dpolicy->type == DPOLICY_UMOUNT && issued) { > > > > > + __wait_all_discard_cmd(sbi, dpolicy); > > > > > + goto retry; > > > > > + } > > > > > + > > > > > if (!issued && io_interrupted) > > > > > issued = -1; > > > > > > > > > > Thanks, > > > > > > > > > > > > > > > > > > > > > > > > > Signed-off-by: Sahitya Tummala <stummala@codeaurora.org> > > > > > > > --- > > > > > > > v3: > > > > > > > -Handle the regression reported by Chao with v2. > > > > > > > -simplify the logic to split the dc with multiple bios incase any bio returns > > > > > > > EAGAIN and retry those new dc within 5 sec timeout. > > > > > > > > > > > > > > fs/f2fs/segment.c | 65 +++++++++++++++++++++++++++++++++++++++++++------------ > > > > > > > 1 file changed, 51 insertions(+), 14 deletions(-) > > > > > > > > > > > > > > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > > > > > > > index fb3e531..55d18c7 100644 > > > > > > > --- a/fs/f2fs/segment.c > > > > > > > +++ b/fs/f2fs/segment.c > > > > > > > @@ -1029,13 +1029,16 @@ static void f2fs_submit_discard_endio(struct bio *bio) > > > > > > > struct discard_cmd *dc = (struct discard_cmd *)bio->bi_private; > > > > > > > unsigned long flags; > > > > > > > > > > > > > > - dc->error = blk_status_to_errno(bio->bi_status); > > > > > > > - > > > > > > > spin_lock_irqsave(&dc->lock, flags); > > > > > > > + if (!dc->error) > > > > > > > + dc->error = blk_status_to_errno(bio->bi_status); > > > > > > > + > > > > > > > dc->bio_ref--; > > > > > > > - if (!dc->bio_ref && dc->state == D_SUBMIT) { > > > > > > > - dc->state = D_DONE; > > > > > > > - complete_all(&dc->wait); > > > > > > > + if (!dc->bio_ref) { > > > > > > > + if (dc->error || dc->state == D_SUBMIT) { > > > > > > > + dc->state = D_DONE; > > > > > > > + complete_all(&dc->wait); > > > > > > > + } > > > > > > > } > > > > > > > spin_unlock_irqrestore(&dc->lock, flags); > > > > > > > bio_put(bio); > > > > > > > @@ -1124,10 +1127,13 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > > > > > > > struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info; > > > > > > > struct list_head *wait_list = (dpolicy->type == DPOLICY_FSTRIM) ? > > > > > > > &(dcc->fstrim_list) : &(dcc->wait_list); > > > > > > > - int flag = dpolicy->sync ? REQ_SYNC : 0; > > > > > > > + int flag; > > > > > > > block_t lstart, start, len, total_len; > > > > > > > int err = 0; > > > > > > > > > > > > > > + flag = dpolicy->sync ? REQ_SYNC : 0; > > > > > > > + flag |= dpolicy->type == DPOLICY_UMOUNT ? REQ_NOWAIT : 0; > > > > > > > + > > > > > > > if (dc->state != D_PREP) > > > > > > > return 0; > > > > > > > > > > > > > > @@ -1192,10 +1198,6 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > > > > > > > dc->bio_ref++; > > > > > > > spin_unlock_irqrestore(&dc->lock, flags); > > > > > > > > > > > > > > - atomic_inc(&dcc->queued_discard); > > > > > > > - dc->queued++; > > > > > > > - list_move_tail(&dc->list, wait_list); > > > > > > > - > > > > > > > /* sanity check on discard range */ > > > > > > > __check_sit_bitmap(sbi, lstart, lstart + len); > > > > > > > > > > > > > > @@ -1203,6 +1205,29 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > > > > > > > bio->bi_end_io = f2fs_submit_discard_endio; > > > > > > > bio->bi_opf |= flag; > > > > > > > submit_bio(bio); > > > > > > > + if (flag & REQ_NOWAIT) { > > > > > > > + if (dc->error == -EAGAIN) { > > > > > > > + spin_lock_irqsave(&dc->lock, flags); > > > > > > > + dc->len -= len; > > > > > > > + if (!dc->len) { > > > > > > > + dc->len = total_len; > > > > > > > + dc->state = D_PREP; > > > > > > > + reinit_completion(&dc->wait); > > > > > > > + } else { > > > > > > > + dcc->undiscard_blks -= total_len; > > > > > > > + if (dc->state == D_PARTIAL) > > > > > > > + dc->state = D_SUBMIT; > > > > > > > + } > > > > > > > + err = dc->error; > > > > > > > + dc->error = 0; > > > > > > > + spin_unlock_irqrestore(&dc->lock, flags); > > > > > > > + break; > > > > > > > + } > > > > > > > + } > > > > > > > + > > > > > > > + atomic_inc(&dcc->queued_discard); > > > > > > > + dc->queued++; > > > > > > > + list_move_tail(&dc->list, wait_list); > > > > > > > > > > > > > > atomic_inc(&dcc->issued_discard); > > > > > > > > > > > > > > @@ -1214,8 +1239,9 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > > > > > > > len = total_len; > > > > > > > } > > > > > > > > > > > > > > - if (!err && len) > > > > > > > - __update_discard_tree_range(sbi, bdev, lstart, start, len); > > > > > > > + if ((!err || err == -EAGAIN) && total_len && dc->start != start) > > > > > > > + __update_discard_tree_range(sbi, bdev, lstart, start, > > > > > > > + total_len); > > > > > > > return err; > > > > > > > } > > > > > > > > > > > > > > @@ -1470,12 +1496,15 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > > > > > > struct list_head *pend_list; > > > > > > > struct discard_cmd *dc, *tmp; > > > > > > > struct blk_plug plug; > > > > > > > - int i, issued = 0; > > > > > > > + int i, err, issued = 0; > > > > > > > bool io_interrupted = false; > > > > > > > + bool retry; > > > > > > > > > > > > > > if (dpolicy->timeout != 0) > > > > > > > f2fs_update_time(sbi, dpolicy->timeout); > > > > > > > > > > > > > > +retry: > > > > > > > + retry = false; > > > > > > > for (i = MAX_PLIST_NUM - 1; i >= 0; i--) { > > > > > > > if (dpolicy->timeout != 0 && > > > > > > > f2fs_time_over(sbi, dpolicy->timeout)) > > > > > > > @@ -1509,7 +1538,12 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > > > > > > break; > > > > > > > } > > > > > > > > > > > > > > - __submit_discard_cmd(sbi, dpolicy, dc, &issued); > > > > > > > + err = __submit_discard_cmd(sbi, dpolicy, dc, &issued); > > > > > > > + if (err == -EAGAIN) { > > > > > > > + congestion_wait(BLK_RW_ASYNC, > > > > > > > + DEFAULT_IO_TIMEOUT); > > > > > > > + retry = true; > > > > > > > + } > > > > > > > > > > > > > > if (issued >= dpolicy->max_requests) > > > > > > > break; > > > > > > > @@ -1522,6 +1556,9 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > > > > > > break; > > > > > > > } > > > > > > > > > > > > > > + if (retry) > > > > > > > + goto retry; > > > > > > > + > > > > > > > if (!issued && io_interrupted) > > > > > > > issued = -1; > > > > > > > > > > > > > > -- > > > > > > > Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc. > > > > > > > Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project. > > > > > > > > > > -- > > > > > -- > > > > > Sent by a consultant of the Qualcomm Innovation Center, Inc. > > > > > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum. > > > > > > -- > > > -- > > > Sent by a consultant of the Qualcomm Innovation Center, Inc. > > > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum. > > -- > -- > Sent by a consultant of the Qualcomm Innovation Center, Inc. > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum. _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [f2fs-dev] [PATCH v3] f2fs: fix long latency due to discard during umount 2020-04-13 16:52 ` Jaegeuk Kim @ 2020-04-14 17:45 ` Jaegeuk Kim 0 siblings, 0 replies; 7+ messages in thread From: Jaegeuk Kim @ 2020-04-14 17:45 UTC (permalink / raw) To: Sahitya Tummala; +Cc: linux-kernel, linux-f2fs-devel Hi Sahitya, Could you please post the revised patch? Thanks, On 04/13, Jaegeuk Kim wrote: > On 04/09, Sahitya Tummala wrote: > > On Wed, Apr 08, 2020 at 07:29:28PM -0700, Jaegeuk Kim wrote: > > > On 04/08, Sahitya Tummala wrote: > > > > Hi Jaegeuk, > > > > > > > > On Fri, Apr 03, 2020 at 10:19:43AM -0700, Jaegeuk Kim wrote: > > > > > On 04/01, Sahitya Tummala wrote: > > > > > > Hi Jaegeuk, > > > > > > > > > > > > On Tue, Mar 31, 2020 at 11:46:55AM -0700, Jaegeuk Kim wrote: > > > > > > > On 03/30, Sahitya Tummala wrote: > > > > > > > > F2FS already has a default timeout of 5 secs for discards that > > > > > > > > can be issued during umount, but it can take more than the 5 sec > > > > > > > > timeout if the underlying UFS device queue is already full and there > > > > > > > > are no more available free tags to be used. In that case, submit_bio() > > > > > > > > will wait for the already queued discard requests to complete to get > > > > > > > > a free tag, which can potentially take way more than 5 sec. > > > > > > > > > > > > > > > > Fix this by submitting the discard requests with REQ_NOWAIT > > > > > > > > flags during umount. This will return -EAGAIN for UFS queue/tag full > > > > > > > > scenario without waiting in the context of submit_bio(). The FS can > > > > > > > > then handle these requests by retrying again within the stipulated > > > > > > > > discard timeout period to avoid long latencies. > > > > > > > > > > > > > > Sorry, Sahitya, but, do we really need to do like this? How about just > > > > > > > controlling # of outstanding discarding bios in __issue_discard_cmd()? > > > > > > > > > > > > Do you mean something like this? > > > > > > > > > > > > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > > > > > > index 1a62b27..860dd43 100644 > > > > > > --- a/fs/f2fs/segment.c > > > > > > +++ b/fs/f2fs/segment.c > > > > > > @@ -1099,7 +1099,7 @@ static void __init_discard_policy(struct f2fs_sb_info *sbi, > > > > > > } else if (discard_type == DPOLICY_FSTRIM) { > > > > > > dpolicy->io_aware = false; > > > > > > } else if (discard_type == DPOLICY_UMOUNT) { > > > > > > - dpolicy->max_requests = UINT_MAX; > > > > > > + dpolicy->max_requests = 30; > > > > > > > > > > Can we use max queue depth of the block device? > > > > > > > > I think it should be limited to 8 or 16 as Chao suggested, so that we can have > > > > better control on the given timeout value? Thoughts? > > > > > > Where is 8 or 16 coming from? What about SSD? Sorry, it's unclear to me. > > > > With this patch we now wait for a batch of discard requests in __issue_discard_cmd() > > with a upper timeout of 5 sec. So, I thought that having a smaller batch of > > discard requests would help us to avoid queuing more requests and end up waiting > > for more time in __wait_all_discard_cmd(). Today we have DEF_MAX_DISCARD_REQUEST > > as 8 for default max discard requests. If it too less, may be for umount > > we can use 16 instead. But the idea is to avoid more wait time. > > Ok, then, it seems we can just remove this line to use dpolicy->max_requests, > and retry issuing all the discard commands like below. Later, I thnk it'd be > fine to tune the max_requests based on bd_queue->queue_depth. > > > > > If you would like to propose to use max queue depth, we can get it from bdev as > > sbi->sb->s_bdev->bd_queue->queue_depth. Is it okay to use it in our FS? or you > > think it should be hardcoded to 32 (as most UFS/eMMC devices will have this as > > its queue depth)? Please let me know. > > > > Thanks, > > > > > > > > > > > > > Thanks, > > > > > > > > > > > > > > > dpolicy->io_aware = false; > > > > > > /* we need to issue all to keep CP_TRIMMED_FLAG */ > > > > > > dpolicy->granularity = 1; > > > > > > @@ -1470,12 +1470,14 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > > > > > struct list_head *pend_list; > > > > > > struct discard_cmd *dc, *tmp; > > > > > > struct blk_plug plug; > > > > > > - int i, issued = 0; > > > > > > + int i, issued; > > > > > > bool io_interrupted = false; > > > > > > > > > > > > if (dpolicy->timeout != 0) > > > > > > f2fs_update_time(sbi, dpolicy->timeout); > > > > > > > > > > > > +retry: > > > > > > + issued = 0; > > > > > > for (i = MAX_PLIST_NUM - 1; i >= 0; i--) { > > > > > > if (dpolicy->timeout != 0 && > > > > > > f2fs_time_over(sbi, dpolicy->timeout)) > > > > > > @@ -1522,6 +1524,11 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > > > > > break; > > > > > > } > > > > > > > > > > > > + if (dpolicy->type == DPOLICY_UMOUNT && issued) { > > > > > > + __wait_all_discard_cmd(sbi, dpolicy); > > > > > > + goto retry; > > > > > > + } > > > > > > + > > > > > > if (!issued && io_interrupted) > > > > > > issued = -1; > > > > > > > > > > > > Thanks, > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Signed-off-by: Sahitya Tummala <stummala@codeaurora.org> > > > > > > > > --- > > > > > > > > v3: > > > > > > > > -Handle the regression reported by Chao with v2. > > > > > > > > -simplify the logic to split the dc with multiple bios incase any bio returns > > > > > > > > EAGAIN and retry those new dc within 5 sec timeout. > > > > > > > > > > > > > > > > fs/f2fs/segment.c | 65 +++++++++++++++++++++++++++++++++++++++++++------------ > > > > > > > > 1 file changed, 51 insertions(+), 14 deletions(-) > > > > > > > > > > > > > > > > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > > > > > > > > index fb3e531..55d18c7 100644 > > > > > > > > --- a/fs/f2fs/segment.c > > > > > > > > +++ b/fs/f2fs/segment.c > > > > > > > > @@ -1029,13 +1029,16 @@ static void f2fs_submit_discard_endio(struct bio *bio) > > > > > > > > struct discard_cmd *dc = (struct discard_cmd *)bio->bi_private; > > > > > > > > unsigned long flags; > > > > > > > > > > > > > > > > - dc->error = blk_status_to_errno(bio->bi_status); > > > > > > > > - > > > > > > > > spin_lock_irqsave(&dc->lock, flags); > > > > > > > > + if (!dc->error) > > > > > > > > + dc->error = blk_status_to_errno(bio->bi_status); > > > > > > > > + > > > > > > > > dc->bio_ref--; > > > > > > > > - if (!dc->bio_ref && dc->state == D_SUBMIT) { > > > > > > > > - dc->state = D_DONE; > > > > > > > > - complete_all(&dc->wait); > > > > > > > > + if (!dc->bio_ref) { > > > > > > > > + if (dc->error || dc->state == D_SUBMIT) { > > > > > > > > + dc->state = D_DONE; > > > > > > > > + complete_all(&dc->wait); > > > > > > > > + } > > > > > > > > } > > > > > > > > spin_unlock_irqrestore(&dc->lock, flags); > > > > > > > > bio_put(bio); > > > > > > > > @@ -1124,10 +1127,13 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > > > > > > > > struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info; > > > > > > > > struct list_head *wait_list = (dpolicy->type == DPOLICY_FSTRIM) ? > > > > > > > > &(dcc->fstrim_list) : &(dcc->wait_list); > > > > > > > > - int flag = dpolicy->sync ? REQ_SYNC : 0; > > > > > > > > + int flag; > > > > > > > > block_t lstart, start, len, total_len; > > > > > > > > int err = 0; > > > > > > > > > > > > > > > > + flag = dpolicy->sync ? REQ_SYNC : 0; > > > > > > > > + flag |= dpolicy->type == DPOLICY_UMOUNT ? REQ_NOWAIT : 0; > > > > > > > > + > > > > > > > > if (dc->state != D_PREP) > > > > > > > > return 0; > > > > > > > > > > > > > > > > @@ -1192,10 +1198,6 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > > > > > > > > dc->bio_ref++; > > > > > > > > spin_unlock_irqrestore(&dc->lock, flags); > > > > > > > > > > > > > > > > - atomic_inc(&dcc->queued_discard); > > > > > > > > - dc->queued++; > > > > > > > > - list_move_tail(&dc->list, wait_list); > > > > > > > > - > > > > > > > > /* sanity check on discard range */ > > > > > > > > __check_sit_bitmap(sbi, lstart, lstart + len); > > > > > > > > > > > > > > > > @@ -1203,6 +1205,29 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > > > > > > > > bio->bi_end_io = f2fs_submit_discard_endio; > > > > > > > > bio->bi_opf |= flag; > > > > > > > > submit_bio(bio); > > > > > > > > + if (flag & REQ_NOWAIT) { > > > > > > > > + if (dc->error == -EAGAIN) { > > > > > > > > + spin_lock_irqsave(&dc->lock, flags); > > > > > > > > + dc->len -= len; > > > > > > > > + if (!dc->len) { > > > > > > > > + dc->len = total_len; > > > > > > > > + dc->state = D_PREP; > > > > > > > > + reinit_completion(&dc->wait); > > > > > > > > + } else { > > > > > > > > + dcc->undiscard_blks -= total_len; > > > > > > > > + if (dc->state == D_PARTIAL) > > > > > > > > + dc->state = D_SUBMIT; > > > > > > > > + } > > > > > > > > + err = dc->error; > > > > > > > > + dc->error = 0; > > > > > > > > + spin_unlock_irqrestore(&dc->lock, flags); > > > > > > > > + break; > > > > > > > > + } > > > > > > > > + } > > > > > > > > + > > > > > > > > + atomic_inc(&dcc->queued_discard); > > > > > > > > + dc->queued++; > > > > > > > > + list_move_tail(&dc->list, wait_list); > > > > > > > > > > > > > > > > atomic_inc(&dcc->issued_discard); > > > > > > > > > > > > > > > > @@ -1214,8 +1239,9 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > > > > > > > > len = total_len; > > > > > > > > } > > > > > > > > > > > > > > > > - if (!err && len) > > > > > > > > - __update_discard_tree_range(sbi, bdev, lstart, start, len); > > > > > > > > + if ((!err || err == -EAGAIN) && total_len && dc->start != start) > > > > > > > > + __update_discard_tree_range(sbi, bdev, lstart, start, > > > > > > > > + total_len); > > > > > > > > return err; > > > > > > > > } > > > > > > > > > > > > > > > > @@ -1470,12 +1496,15 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > > > > > > > struct list_head *pend_list; > > > > > > > > struct discard_cmd *dc, *tmp; > > > > > > > > struct blk_plug plug; > > > > > > > > - int i, issued = 0; > > > > > > > > + int i, err, issued = 0; > > > > > > > > bool io_interrupted = false; > > > > > > > > + bool retry; > > > > > > > > > > > > > > > > if (dpolicy->timeout != 0) > > > > > > > > f2fs_update_time(sbi, dpolicy->timeout); > > > > > > > > > > > > > > > > +retry: > > > > > > > > + retry = false; > > > > > > > > for (i = MAX_PLIST_NUM - 1; i >= 0; i--) { > > > > > > > > if (dpolicy->timeout != 0 && > > > > > > > > f2fs_time_over(sbi, dpolicy->timeout)) > > > > > > > > @@ -1509,7 +1538,12 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > > > > > > > break; > > > > > > > > } > > > > > > > > > > > > > > > > - __submit_discard_cmd(sbi, dpolicy, dc, &issued); > > > > > > > > + err = __submit_discard_cmd(sbi, dpolicy, dc, &issued); > > > > > > > > + if (err == -EAGAIN) { > > > > > > > > + congestion_wait(BLK_RW_ASYNC, > > > > > > > > + DEFAULT_IO_TIMEOUT); > > > > > > > > + retry = true; > > > > > > > > + } > > > > > > > > > > > > > > > > if (issued >= dpolicy->max_requests) > > > > > > > > break; > > > > > > > > @@ -1522,6 +1556,9 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, > > > > > > > > break; > > > > > > > > } > > > > > > > > > > > > > > > > + if (retry) > > > > > > > > + goto retry; > > > > > > > > + > > > > > > > > if (!issued && io_interrupted) > > > > > > > > issued = -1; > > > > > > > > > > > > > > > > -- > > > > > > > > Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc. > > > > > > > > Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project. > > > > > > > > > > > > -- > > > > > > -- > > > > > > Sent by a consultant of the Qualcomm Innovation Center, Inc. > > > > > > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum. > > > > > > > > -- > > > > -- > > > > Sent by a consultant of the Qualcomm Innovation Center, Inc. > > > > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum. > > > > -- > > -- > > Sent by a consultant of the Qualcomm Innovation Center, Inc. > > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum. > > > _______________________________________________ > Linux-f2fs-devel mailing list > Linux-f2fs-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel ^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2020-04-14 17:46 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
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[not found] <1585550730-1858-1-git-send-email-stummala@codeaurora.org>
2020-03-31 18:46 ` [f2fs-dev] [PATCH v3] f2fs: fix long latency due to discard during umount Jaegeuk Kim
2020-04-01 9:22 ` Sahitya Tummala
2020-04-02 9:32 ` Chao Yu
2020-04-03 17:19 ` Jaegeuk Kim
[not found] ` <20200408090024.GC20234@codeaurora.org>
2020-04-09 2:29 ` Jaegeuk Kim
[not found] ` <20200409114756.GD20234@codeaurora.org>
2020-04-13 16:52 ` Jaegeuk Kim
2020-04-14 17:45 ` Jaegeuk Kim
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