From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 09CF1C4332F for ; Fri, 9 Dec 2022 20:00:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229938AbiLIUAC (ORCPT ); Fri, 9 Dec 2022 15:00:02 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48432 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229847AbiLIT76 (ORCPT ); Fri, 9 Dec 2022 14:59:58 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 24FD113F7F for ; Fri, 9 Dec 2022 11:59:56 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 2E2CDB82905 for ; Fri, 9 Dec 2022 19:59:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B98C2C433D2; Fri, 9 Dec 2022 19:59:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1670615993; bh=APLv10D7XtvFX9HKL9kA1ew1UoIKNDoxYrNVlNz/a9E=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=HU7eLdrCjm/yeqpgdeUBFy6gC10h2B/Nk4VFkmYHJoom8T6VJ7ne1nWPzWrL9KoQq qWTU6/56nCoP8fdgUMvaDe8N9mzqTL45k7ffuIuXDv5efg/VCpY6VquAUWGZZI5CM6 2qYrtbMQwJ/+dgEptJbHJ2K0eYbcW8IIAsk/ItkfPqXJy+b9639gy7leS8Z0Za1QRw UJblWdPiYHz7gP0MgxBJ74cYb77hJHUF+/nV4B1TMqBxctp9pIvBZhiOIVxYy8PWGA t+6G7ueb/h2LMXZ1dZGUEO5HCBBgWLYAZ/ZU7xZmhVr8opcWGugXZ18c0FVLVhEwU6 TWzZpoQx0+WcQ== Date: Fri, 9 Dec 2022 11:59:52 -0800 From: Jaegeuk Kim To: Yangtao Li Cc: chao@kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] f2fs: add support for counting the average time of submit discard cmd Message-ID: References: <20221129041524.81235-1-frank.li@vivo.com> <20221129041524.81235-2-frank.li@vivo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221129041524.81235-2-frank.li@vivo.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/29, Yangtao Li wrote: > This patch adds support for counting the average time of submit discard > command, and we can see its value in debugfs. What about peak latencies as well? > > Signed-off-by: Yangtao Li > --- > fs/f2fs/debug.c | 7 +++++-- > fs/f2fs/f2fs.h | 5 +++++ > fs/f2fs/segment.c | 18 ++++++++++++++++-- > 3 files changed, 26 insertions(+), 4 deletions(-) > > diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c > index 733b1bd37404..eed3edfc5faf 100644 > --- a/fs/f2fs/debug.c > +++ b/fs/f2fs/debug.c > @@ -109,6 +109,9 @@ static void update_general_status(struct f2fs_sb_info *sbi) > llist_empty(&SM_I(sbi)->fcc_info->issue_list); > } > if (SM_I(sbi)->dcc_info) { > + struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info; > + > + si->discard_avg = dcc->discard_time_avg; > si->nr_discarded = > atomic_read(&SM_I(sbi)->dcc_info->issued_discard); > si->nr_discarding = > @@ -510,8 +513,8 @@ static int stat_show(struct seq_file *s, void *v) > si->nr_wb_cp_data, si->nr_wb_data, > si->nr_flushing, si->nr_flushed, > si->flush_list_empty); > - seq_printf(s, "Discard: (%4d %4d)) cmd: %4d undiscard:%4u\n", > - si->nr_discarding, si->nr_discarded, > + seq_printf(s, "Discard: (%4d %4d, avg:%4lldns)) cmd: %4d undiscard:%4u\n", > + si->nr_discarding, si->nr_discarded, ktime_to_us(si->discard_avg), > si->nr_discard_cmd, si->undiscard_blks); > seq_printf(s, " - atomic IO: %4d (Max. %4d)\n", > si->aw_cnt, si->max_aw_cnt); > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > index eb8c27c4e5fc..5a99759d10ac 100644 > --- a/fs/f2fs/f2fs.h > +++ b/fs/f2fs/f2fs.h > @@ -370,6 +370,8 @@ struct discard_cmd { > int error; /* bio error */ > spinlock_t lock; /* for state/bio_ref updating */ > unsigned short bio_ref; /* bio reference count */ > + struct discard_cmd_control *dcc; /* global discard cmd control */ > + ktime_t submit_start; /* submit start time */ > }; > > enum { > @@ -414,6 +416,8 @@ struct discard_cmd_control { > unsigned int max_ordered_discard; /* maximum discard granularity issued by lba order */ > unsigned int undiscard_blks; /* # of undiscard blocks */ > unsigned int next_pos; /* next discard position */ > + spinlock_t discard_time_lock; /* for discard time statistics */ > + ktime_t discard_time_avg; /* issued discard cmd avg time */ > atomic_t issued_discard; /* # of issued discard */ > atomic_t queued_discard; /* # of queued discard */ > atomic_t discard_cmd_cnt; /* # of cached cmd count */ > @@ -3882,6 +3886,7 @@ struct f2fs_stat_info { > int nr_dio_read, nr_dio_write; > unsigned int io_skip_bggc, other_skip_bggc; > int nr_flushing, nr_flushed, flush_list_empty; > + ktime_t discard_avg; > int nr_discarding, nr_discarded; > int nr_discard_cmd; > unsigned int undiscard_blks; > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > index 9486ca49ecb1..bc96b1afb308 100644 > --- a/fs/f2fs/segment.c > +++ b/fs/f2fs/segment.c > @@ -931,6 +931,7 @@ static struct discard_cmd *__create_discard_cmd(struct f2fs_sb_info *sbi, > list_add_tail(&dc->list, pend_list); > spin_lock_init(&dc->lock); > dc->bio_ref = 0; > + dc->dcc = dcc; > atomic_inc(&dcc->discard_cmd_cnt); > dcc->undiscard_blks += len; > > @@ -1000,9 +1001,13 @@ static void __remove_discard_cmd(struct f2fs_sb_info *sbi, > static void f2fs_submit_discard_endio(struct bio *bio) > { > struct discard_cmd *dc = (struct discard_cmd *)bio->bi_private; > + struct discard_cmd_control *dcc = dc->dcc; > unsigned long flags; > + ktime_t submit_time; > + int nr_discarded; > > spin_lock_irqsave(&dc->lock, flags); > + submit_time = ktime_sub(ktime_get(), dc->submit_start); > if (!dc->error) > dc->error = blk_status_to_errno(bio->bi_status); > dc->bio_ref--; > @@ -1012,6 +1017,14 @@ static void f2fs_submit_discard_endio(struct bio *bio) > } > spin_unlock_irqrestore(&dc->lock, flags); > bio_put(bio); > + > + spin_lock_irqsave(&dcc->discard_time_lock, flags); > + nr_discarded = atomic_read(&dcc->issued_discard); > + dcc->discard_time_avg = div_u64(ktime_add(nr_discarded * dcc->discard_time_avg, > + submit_time), > + nr_discarded + 1); > + atomic_inc(&dcc->issued_discard); > + spin_unlock_irqrestore(&dcc->discard_time_lock, flags); > } > > static void __check_sit_bitmap(struct f2fs_sb_info *sbi, > @@ -1160,6 +1173,7 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > * right away > */ > spin_lock_irqsave(&dc->lock, flags); > + dc->submit_start = ktime_get(); > if (last) > dc->state = D_SUBMIT; > else > @@ -1179,8 +1193,6 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi, > bio->bi_opf |= flag; > submit_bio(bio); > > - atomic_inc(&dcc->issued_discard); > - > f2fs_update_iostat(sbi, NULL, FS_DISCARD, 1); > > lstart += len; > @@ -2070,9 +2082,11 @@ static int create_discard_cmd_control(struct f2fs_sb_info *sbi) > INIT_LIST_HEAD(&dcc->wait_list); > INIT_LIST_HEAD(&dcc->fstrim_list); > mutex_init(&dcc->cmd_lock); > + spin_lock_init(&dcc->discard_time_lock); > atomic_set(&dcc->issued_discard, 0); > atomic_set(&dcc->queued_discard, 0); > atomic_set(&dcc->discard_cmd_cnt, 0); > + dcc->discard_time_avg = 0; > dcc->nr_discards = 0; > dcc->max_discards = MAIN_SEGS(sbi) << sbi->log_blocks_per_seg; > dcc->max_discard_request = DEF_MAX_DISCARD_REQUEST; > -- > 2.25.1