Date:   Tue, 31 Jan 2023 10:53:48 -0800
From:   Jaegeuk Kim <jaegeuk@kernel.org>
To:     Chao Yu <chao@kernel.org>
Cc:     Yangtao Li <frank.li@vivo.com>,
        linux-f2fs-devel@lists.sourceforge.net,
        linux-kernel@vger.kernel.org, kernel test robot <lkp@intel.com>,
        Dan Carpenter <error27@gmail.com>
Subject: Re: [PATCH v3 2/2] f2fs: use iostat_lat_type directly as a parameter
 in the iostat_update_and_unbind_ctx()
Message-ID: <Y9ljvM5aLxgpK3ZF@google.com>
References: <20230120161656.70308-1-frank.li@vivo.com>
 <20230120161656.70308-2-frank.li@vivo.com>
 <855c7c54-57f6-dcf8-9218-0dba6e216fd4@kernel.org>
MIME-Version: 1.0
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In-Reply-To: <855c7c54-57f6-dcf8-9218-0dba6e216fd4@kernel.org>
Precedence: bulk

On 01/31, Chao Yu wrote:
> On 2023/1/21 0:16, Yangtao Li wrote:
> > Convert to use iostat_lat_type as parameter instead of raw number.
> > BTW, move NUM_PREALLOC_IOSTAT_CTXS to the header file, and rename
> > iotype to page_type to match the definition.
> > 
> > Reported-by: kernel test robot <lkp@intel.com>
> > Reported-by: Dan Carpenter <error27@gmail.com>
> > Signed-off-by: Yangtao Li <frank.li@vivo.com>
> > ---
> > v3:
> > -convert to f2fs_warn()
> >   fs/f2fs/data.c   |  4 ++--
> >   fs/f2fs/iostat.c | 39 ++++++++++++++++-----------------------
> >   fs/f2fs/iostat.h | 19 ++++++++++---------
> >   3 files changed, 28 insertions(+), 34 deletions(-)
> > 
> > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> > index 1645b8a1b904..710d4acde187 100644
> > --- a/fs/f2fs/data.c
> > +++ b/fs/f2fs/data.c
> > @@ -292,7 +292,7 @@ static void f2fs_read_end_io(struct bio *bio)
> >   	struct bio_post_read_ctx *ctx;
> >   	bool intask = in_task();
> > -	iostat_update_and_unbind_ctx(bio, 0);
> > +	iostat_update_and_unbind_ctx(bio, READ_IO);
> >   	ctx = bio->bi_private;
> >   	if (time_to_inject(sbi, FAULT_READ_IO))
> > @@ -330,7 +330,7 @@ static void f2fs_write_end_io(struct bio *bio)
> >   	struct bio_vec *bvec;
> >   	struct bvec_iter_all iter_all;
> > -	iostat_update_and_unbind_ctx(bio, 1);
> > +	iostat_update_and_unbind_ctx(bio, bio->bi_opf & REQ_SYNC ? WRITE_SYNC_IO : WRITE_ASYNC_IO);
> >   	sbi = bio->bi_private;
> >   	if (time_to_inject(sbi, FAULT_WRITE_IO))
> > diff --git a/fs/f2fs/iostat.c b/fs/f2fs/iostat.c
> > index 96637756eae8..c767a2e7d5a9 100644
> > --- a/fs/f2fs/iostat.c
> > +++ b/fs/f2fs/iostat.c
> > @@ -14,7 +14,6 @@
> >   #include "iostat.h"
> >   #include <trace/events/f2fs.h>
> > -#define NUM_PREALLOC_IOSTAT_CTXS	128
> >   static struct kmem_cache *bio_iostat_ctx_cache;
> >   static mempool_t *bio_iostat_ctx_pool;
> > @@ -210,53 +209,47 @@ void f2fs_update_iostat(struct f2fs_sb_info *sbi, struct inode *inode,
> >   }
> >   static inline void __update_iostat_latency(struct bio_iostat_ctx *iostat_ctx,
> > -				int rw, bool is_sync)
> > +				enum iostat_lat_type lat_type)
> >   {
> >   	unsigned long ts_diff;
> > -	unsigned int iotype = iostat_ctx->type;
> > +	unsigned int page_type = iostat_ctx->type;
> >   	struct f2fs_sb_info *sbi = iostat_ctx->sbi;
> >   	struct iostat_lat_info *io_lat = sbi->iostat_io_lat;
> > -	int idx;
> >   	unsigned long flags;
> >   	if (!sbi->iostat_enable)
> >   		return;
> >   	ts_diff = jiffies - iostat_ctx->submit_ts;
> > -	if (iotype == META_FLUSH) {
> > -		iotype = META;
> > -	} else if (iotype >= NR_PAGE_TYPE) {
> > -		f2fs_warn(sbi, "%s: %d over NR_PAGE_TYPE", __func__, iotype);
> > +	if (page_type == META_FLUSH) {
> > +		page_type = META;
> > +	} else if (page_type >= NR_PAGE_TYPE) {
> > +		f2fs_warn(sbi, "%s: %d over NR_PAGE_TYPE", __func__, page_type);
> >   		return;
> >   	}
> > -	if (rw == 0) {
> > -		idx = READ_IO;
> > -	} else {
> > -		if (is_sync)
> > -			idx = WRITE_SYNC_IO;
> > -		else
> > -			idx = WRITE_ASYNC_IO;
> > +	if (lat_type >= MAX_IO_TYPE) {
> > +		f2fs_warn(sbi, "%s: %d over MAX_IO_TYPE", __func__, lat_type);
> > +		return;
> >   	}
> >   	spin_lock_irqsave(&sbi->iostat_lat_lock, flags);
> > -	io_lat->sum_lat[idx][iotype] += ts_diff;
> > -	io_lat->bio_cnt[idx][iotype]++;
> > -	if (ts_diff > io_lat->peak_lat[idx][iotype])
> > -		io_lat->peak_lat[idx][iotype] = ts_diff;
> > +	io_lat->sum_lat[lat_type][page_type] += ts_diff;
> > +	io_lat->bio_cnt[lat_type][page_type]++;
> > +	if (ts_diff > io_lat->peak_lat[lat_type][page_type])
> > +		io_lat->peak_lat[lat_type][page_type] = ts_diff;
> >   	spin_unlock_irqrestore(&sbi->iostat_lat_lock, flags);
> >   }
> > -void iostat_update_and_unbind_ctx(struct bio *bio, int rw)
> > +void iostat_update_and_unbind_ctx(struct bio *bio, enum iostat_lat_type lat_type)
> >   {
> >   	struct bio_iostat_ctx *iostat_ctx = bio->bi_private;
> > -	bool is_sync = bio->bi_opf & REQ_SYNC;
> > -	if (rw == 0)
> > +	if (lat_type == READ_IO)
> >   		bio->bi_private = iostat_ctx->post_read_ctx;
> >   	else
> >   		bio->bi_private = iostat_ctx->sbi;
> > -	__update_iostat_latency(iostat_ctx, rw, is_sync);
> > +	__update_iostat_latency(iostat_ctx, lat_type);
> >   	mempool_free(iostat_ctx, bio_iostat_ctx_pool);
> >   }
> > diff --git a/fs/f2fs/iostat.h b/fs/f2fs/iostat.h
> > index 2c048307b6e0..1f827a2fe6b2 100644
> > --- a/fs/f2fs/iostat.h
> > +++ b/fs/f2fs/iostat.h
> > @@ -8,20 +8,21 @@
> >   struct bio_post_read_ctx;
> > +enum iostat_lat_type {
> > +	READ_IO = 0,
> > +	WRITE_SYNC_IO,
> > +	WRITE_ASYNC_IO,
> > +	MAX_IO_TYPE,
> > +};
> 
> How about adjusting iostat_lat[{0,1,2}] to iostat_lat[{READ_IO,WRITE_SYNC_IO,WRITE_ASYNC_IO}]
> in tracepoint function.
> 
> 	TP_fast_assign(
> 		__entry->dev		= sbi->sb->s_dev;
> 		__entry->d_rd_peak	= iostat_lat[0][DATA].peak_lat;
> 		__entry->d_rd_avg	= iostat_lat[0][DATA].avg_lat;
> 		__entry->d_rd_cnt	= iostat_lat[0][DATA].cnt;
> 		__entry->n_rd_peak	= iostat_lat[0][NODE].peak_lat;
> 		__entry->n_rd_avg	= iostat_lat[0][NODE].avg_lat;
> 		__entry->n_rd_cnt	= iostat_lat[0][NODE].cnt;
> 		__entry->m_rd_peak	= iostat_lat[0][META].peak_lat;
> 		__entry->m_rd_avg	= iostat_lat[0][META].avg_lat;
> 		__entry->m_rd_cnt	= iostat_lat[0][META].cnt;
> 		__entry->d_wr_s_peak	= iostat_lat[1][DATA].peak_lat;
> 		__entry->d_wr_s_avg	= iostat_lat[1][DATA].avg_lat;
> 		__entry->d_wr_s_cnt	= iostat_lat[1][DATA].cnt;
> 		__entry->n_wr_s_peak	= iostat_lat[1][NODE].peak_lat;
> 		__entry->n_wr_s_avg	= iostat_lat[1][NODE].avg_lat;
> 		__entry->n_wr_s_cnt	= iostat_lat[1][NODE].cnt;
> 		__entry->m_wr_s_peak	= iostat_lat[1][META].peak_lat;
> 		__entry->m_wr_s_avg	= iostat_lat[1][META].avg_lat;
> 		__entry->m_wr_s_cnt	= iostat_lat[1][META].cnt;
> 		__entry->d_wr_as_peak	= iostat_lat[2][DATA].peak_lat;
> 		__entry->d_wr_as_avg	= iostat_lat[2][DATA].avg_lat;
> 		__entry->d_wr_as_cnt	= iostat_lat[2][DATA].cnt;
> 		__entry->n_wr_as_peak	= iostat_lat[2][NODE].peak_lat;
> 		__entry->n_wr_as_avg	= iostat_lat[2][NODE].avg_lat;
> 		__entry->n_wr_as_cnt	= iostat_lat[2][NODE].cnt;
> 		__entry->m_wr_as_peak	= iostat_lat[2][META].peak_lat;
> 		__entry->m_wr_as_avg	= iostat_lat[2][META].avg_lat;
> 		__entry->m_wr_as_cnt	= iostat_lat[2][META].cnt;
> 	),

Yangtao,

Could you please send another patch to address the Choa's suggestion?

Thanks,

> 
> Thanks,
> 
> > +
> >   #ifdef CONFIG_F2FS_IOSTAT
> > +#define NUM_PREALLOC_IOSTAT_CTXS	128
> >   #define DEFAULT_IOSTAT_PERIOD_MS	3000
> >   #define MIN_IOSTAT_PERIOD_MS		100
> >   /* maximum period of iostat tracing is 1 day */
> >   #define MAX_IOSTAT_PERIOD_MS		8640000
> > -enum {
> > -	READ_IO,
> > -	WRITE_SYNC_IO,
> > -	WRITE_ASYNC_IO,
> > -	MAX_IO_TYPE,
> > -};
> > -
> >   struct iostat_lat_info {
> >   	unsigned long sum_lat[MAX_IO_TYPE][NR_PAGE_TYPE];	/* sum of io latencies */
> >   	unsigned long peak_lat[MAX_IO_TYPE][NR_PAGE_TYPE];	/* peak io latency */
> > @@ -57,7 +58,7 @@ static inline struct bio_post_read_ctx *get_post_read_ctx(struct bio *bio)
> >   	return iostat_ctx->post_read_ctx;
> >   }
> > -extern void iostat_update_and_unbind_ctx(struct bio *bio, int rw);
> > +extern void iostat_update_and_unbind_ctx(struct bio *bio, enum iostat_lat_type type);
> >   extern void iostat_alloc_and_bind_ctx(struct f2fs_sb_info *sbi,
> >   		struct bio *bio, struct bio_post_read_ctx *ctx);
> >   extern int f2fs_init_iostat_processing(void);
> > @@ -67,7 +68,7 @@ extern void f2fs_destroy_iostat(struct f2fs_sb_info *sbi);
> >   #else
> >   static inline void f2fs_update_iostat(struct f2fs_sb_info *sbi, struct inode *inode,
> >   		enum iostat_type type, unsigned long long io_bytes) {}
> > -static inline void iostat_update_and_unbind_ctx(struct bio *bio, int rw) {}
> > +static inline void iostat_update_and_unbind_ctx(struct bio *bio, enum iostat_lat_type type) {}
> >   static inline void iostat_alloc_and_bind_ctx(struct f2fs_sb_info *sbi,
> >   		struct bio *bio, struct bio_post_read_ctx *ctx) {}
> >   static inline void iostat_update_submit_ctx(struct bio *bio,