Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Yangtao Li <frank.li@vivo.com>
To:     jaegeuk@kernel.org, chao@kernel.org
Cc:     linux-f2fs-devel@lists.sourceforge.net,
        linux-kernel@vger.kernel.org, Yangtao Li <frank.li@vivo.com>
Subject: [PATCH 2/2] f2fs: add support for counting the average time of submit discard cmd
Date:   Tue, 29 Nov 2022 12:15:24 +0800
Message-Id: <20221129041524.81235-2-frank.li@vivo.com>
In-Reply-To: <20221129041524.81235-1-frank.li@vivo.com>
References: <20221129041524.81235-1-frank.li@vivo.com>
Content-Transfer-Encoding: 8bit
Content-Type: text/plain
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?EWGhgx80c5pCH7zxTggscB79d6tIX7vkNzBIV/JbKyfc3miFFbEI7F7o0A+P?=
 =?us-ascii?Q?KfgWEzMovnr0hhTqGavwLvea5pMY3WqR4eiyApwMR+krDQKjIiTMqDLH/zFf?=
 =?us-ascii?Q?UMdMBOrdNAj3JswWOAVkoQbzcVxIZZUQ25qvh5GI8J6lXsPMLefX0xTSm+Wa?=
 =?us-ascii?Q?WgdS32aFeqsiP9iY8nd5B9T/k/BxTfNkoYUaqx9Uq7CvKWLEPaeySC8JIgPA?=
 =?us-ascii?Q?VCH3A0VGSwMkGuQBfK4Ahih2ZenJ0hGF1KpWVcKSATV8vPth5Uc9A03lMnVu?=
 =?us-ascii?Q?dn0S4NhMfV3jdO44tBDa8fcgEMgjCUORyaKgrLkcU5X4y2DLTTnkp6CNg9gg?=
 =?us-ascii?Q?vGFm24VOFN0JGvPuWSJwnlWLUtIjNEf/8T47qDP5lnH2qAPO5kGYkOsc7jxG?=
 =?us-ascii?Q?S47DughKrsNkNAvV7h79vxpkWlmhtFEH6sYQFGF8vOPqRUE/20mq8rgdW1Gd?=
 =?us-ascii?Q?Juegzs45LMmr5i0SKwZwKud0kADRKw00aJ/V2keZKzemWkJAapf2o7mc5pct?=
 =?us-ascii?Q?HpcRYt0adcUiuP2udXsb1twDzk5onetPfzMSBcGAcInfSLLP9SmLPj+q7KDL?=
 =?us-ascii?Q?95iKztgP3hD8xR+BEKkbN2JFFrlF8Wi9znKYFLC/ObrrtcVNNNzmc3RfsTlA?=
 =?us-ascii?Q?e5cdS9bOITHblsApk/STqwydn6snIFrps8twTiE9kAUChsxtpmHnMxFVjIpY?=
 =?us-ascii?Q?RhEJVuTklpMJpcWXMkUYL9P3AYcXfhMhE5hYm3/2m1NkrJGOYed44PaP0GhU?=
 =?us-ascii?Q?VTQfJ8Nrf18WdaPaHGkDZbXqoNEZWVHKnCj0fnyTHZbtQMS5jVkD/p0+cgJj?=
 =?us-ascii?Q?qPampw8o7LttrhqzvC2LWX8+RKbCBZonpYswY589AVRa3BPVy/v5S4eLDvqT?=
 =?us-ascii?Q?kjQM2RIF5zzQA1hfd1JiOZA19t2Jvmfzxrs3n1jwEWOJwHRfhPgfZIod8nK8?=
 =?us-ascii?Q?girHY/JcekyiYVFR9JPINHCJF5H2p6qMTByI6QxupbFNlT4f70xNybXSaxlh?=
 =?us-ascii?Q?Tqg84GkbWoYLtLE0Sw5q/xet38soZfs5AIotZNsYxGmJnzoz08mGzZivCUkH?=
 =?us-ascii?Q?m1asLA+UC7EH+73bspx9d3rydOgHDieuTtaxcVMMakG7ArO5s9yJpAr32neJ?=
 =?us-ascii?Q?cCD9crtd/Dc4XmHMai7rPnbSfZTtUlKnP/9tG+1i3Cr17gR5OUT4puKXsoDK?=
 =?us-ascii?Q?zAe90EBYywBf2+SZvME0afI3D19dnsknriQ514+G7Hbl1dkXZfUruiNncPbV?=
 =?us-ascii?Q?mxI5VYnEdtiwj1AO/6QCX/EkWWTESWpLLDUvg55REsH3N07dLN6xfTlMqSsF?=
 =?us-ascii?Q?Ecdx6dCTNZD2PzHA40TzmTwlXagYNV+vJ0pG4RuFACjulc873mgDZEio3z3S?=
 =?us-ascii?Q?57nZvyVz1n5ttVuQ/vLe+1SQ9gdiGiH3bRmtVmLF5kcv5s2QlayDLmS7Jap/?=
 =?us-ascii?Q?FEb7ibzcfFNk+1hOOFCFAso8ktrAXVsszfszDsNpbjPx0f1StILm2bm5zIwL?=
 =?us-ascii?Q?nzzMdnD9nhOg0hxrSsjtKs2GPlrZHvoJOqdkIqkGGf2OCxE/r2CSVLsSWiVD?=
 =?us-ascii?Q?cTa29WaNVKA4zYLA5XK0JmPTVnNZVHanWvhv5/2A?=
X-OriginatorOrg: vivo.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 4c2bfb4e-1bc7-4c11-ba0a-08dad1c05f96
X-MS-Exchange-CrossTenant-AuthSource: SEZPR06MB5269.apcprd06.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 29 Nov 2022 04:15:39.5079
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 923e42dc-48d5-4cbe-b582-1a797a6412ed
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: 2FCirnqLUOFjPlsscw1iVbEI+DitCbU1Vkk424w5uXOXERBr3NwsdmrafhPU5miSnODJ+PwmafTEzof6Gb3NPA==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: TY0PR06MB5657
X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED,
        DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE,
        RCVD_IN_MSPIKE_H2,SPF_HELO_PASS,SPF_PASS autolearn=ham
        autolearn_force=no version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
        lindbergh.monkeyblade.net
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

This patch adds support for counting the average time of submit discard
command, and we can see its value in debugfs.

Signed-off-by: Yangtao Li <frank.li@vivo.com>
---
 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