[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20131223083903.GA9199@quack.suse.cz>
Date: Mon, 23 Dec 2013 09:39:03 +0100
From: Jan Kara <jack@...e.cz>
To: Zheng Liu <gnehzuil.liu@...il.com>
Cc: linux-ext4@...r.kernel.org, Theodore Ts'o <tytso@....edu>,
Andreas Dilger <adilger.kernel@...ger.ca>,
Zheng Liu <wenqing.lz@...bao.com>
Subject: Re: [RFC PATCH 1/2] ext4: improve extents status tree trace point
On Fri 20-12-13 18:42:44, Zheng Liu wrote:
> From: Zheng Liu <wenqing.lz@...bao.com>
>
> This commit improves the trace point of extents status tree. For
> improving the shrinker, we need to collect more details from trace
> point. First we put more enter/exit pairs in insertion, deletion,
> and caching code path in order to collect the latency of these code
> path. Then we rename trace_ext4_es_shrink_enter in ext4_es_count()
> because it is also used in ext4_es_scan() and we don't identify
> them from the result.
Umm, I think you can use a generic 'function trace' infrastructure to
trace entry & exit into arbitrary functions in kernel. So there shouldn't
be a need to introduce extra entry & exit tracepoints.
Honza
> Cc: "Theodore Ts'o" <tytso@....edu>
> Cc: Andreas Dilger <adilger.kernel@...ger.ca>
> Signed-off-by: Zheng Liu <wenqing.lz@...bao.com>
> ---
> fs/ext4/extents_status.c | 15 ++++++++------
> include/trace/events/ext4.h | 46 ++++++++++++++++++++++++++++++++++++++-----
> 2 files changed, 50 insertions(+), 11 deletions(-)
>
> diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c
> index 3981ff7..e842d74 100644
> --- a/fs/ext4/extents_status.c
> +++ b/fs/ext4/extents_status.c
> @@ -660,7 +660,7 @@ int ext4_es_insert_extent(struct inode *inode, ext4_lblk_t lblk,
> newes.es_len = len;
> ext4_es_store_pblock(&newes, pblk);
> ext4_es_store_status(&newes, status);
> - trace_ext4_es_insert_extent(inode, &newes);
> + trace_ext4_es_insert_extent_enter(inode, &newes);
>
> ext4_es_insert_extent_check(inode, &newes);
>
> @@ -678,6 +678,7 @@ retry:
>
> error:
> write_unlock(&EXT4_I(inode)->i_es_lock);
> + trace_ext4_es_insert_extent_exit(inode, &newes);
>
> ext4_es_print_tree(inode);
>
> @@ -701,7 +702,7 @@ void ext4_es_cache_extent(struct inode *inode, ext4_lblk_t lblk,
> newes.es_len = len;
> ext4_es_store_pblock(&newes, pblk);
> ext4_es_store_status(&newes, status);
> - trace_ext4_es_cache_extent(inode, &newes);
> + trace_ext4_es_cache_extent_enter(inode, &newes);
>
> if (!len)
> return;
> @@ -714,6 +715,7 @@ void ext4_es_cache_extent(struct inode *inode, ext4_lblk_t lblk,
> if (!es || es->es_lblk > end)
> __es_insert_extent(inode, &newes);
> write_unlock(&EXT4_I(inode)->i_es_lock);
> + trace_ext4_es_cache_extent_exit(inode, &newes);
> }
>
> /*
> @@ -887,7 +889,7 @@ int ext4_es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
> ext4_lblk_t end;
> int err = 0;
>
> - trace_ext4_es_remove_extent(inode, lblk, len);
> + trace_ext4_es_remove_extent_enter(inode, lblk, len);
> es_debug("remove [%u/%u) from extent status tree of inode %lu\n",
> lblk, len, inode->i_ino);
>
> @@ -901,6 +903,7 @@ int ext4_es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
> err = __es_remove_extent(inode, lblk, end);
> write_unlock(&EXT4_I(inode)->i_es_lock);
> ext4_es_print_tree(inode);
> + trace_ext4_es_remove_extent_exit(inode, lblk, len);
> return err;
> }
>
> @@ -1017,7 +1020,7 @@ static unsigned long ext4_es_count(struct shrinker *shrink,
>
> sbi = container_of(shrink, struct ext4_sb_info, s_es_shrinker);
> nr = percpu_counter_read_positive(&sbi->s_extent_cache_cnt);
> - trace_ext4_es_shrink_enter(sbi->s_sb, sc->nr_to_scan, nr);
> + trace_ext4_es_shrink_count(sbi->s_sb, sc->nr_to_scan, nr);
> return nr;
> }
>
> @@ -1030,14 +1033,14 @@ static unsigned long ext4_es_scan(struct shrinker *shrink,
> int ret, nr_shrunk;
>
> ret = percpu_counter_read_positive(&sbi->s_extent_cache_cnt);
> - trace_ext4_es_shrink_enter(sbi->s_sb, nr_to_scan, ret);
> + trace_ext4_es_shrink_scan_enter(sbi->s_sb, nr_to_scan, ret);
>
> if (!nr_to_scan)
> return ret;
>
> nr_shrunk = __ext4_es_shrink(sbi, nr_to_scan, NULL);
>
> - trace_ext4_es_shrink_exit(sbi->s_sb, nr_shrunk, ret);
> + trace_ext4_es_shrink_scan_exit(sbi->s_sb, nr_shrunk, ret);
> return nr_shrunk;
> }
>
> diff --git a/include/trace/events/ext4.h b/include/trace/events/ext4.h
> index 197d312..8b3ff82 100644
> --- a/include/trace/events/ext4.h
> +++ b/include/trace/events/ext4.h
> @@ -2221,19 +2221,31 @@ DECLARE_EVENT_CLASS(ext4__es_extent,
> __entry->pblk, show_extent_status(__entry->status))
> );
>
> -DEFINE_EVENT(ext4__es_extent, ext4_es_insert_extent,
> +DEFINE_EVENT(ext4__es_extent, ext4_es_insert_extent_enter,
> TP_PROTO(struct inode *inode, struct extent_status *es),
>
> TP_ARGS(inode, es)
> );
>
> -DEFINE_EVENT(ext4__es_extent, ext4_es_cache_extent,
> +DEFINE_EVENT(ext4__es_extent, ext4_es_insert_extent_exit,
> TP_PROTO(struct inode *inode, struct extent_status *es),
>
> TP_ARGS(inode, es)
> );
>
> -TRACE_EVENT(ext4_es_remove_extent,
> +DEFINE_EVENT(ext4__es_extent, ext4_es_cache_extent_enter,
> + TP_PROTO(struct inode *inode, struct extent_status *es),
> +
> + TP_ARGS(inode, es)
> +);
> +
> +DEFINE_EVENT(ext4__es_extent, ext4_es_cache_extent_exit,
> + TP_PROTO(struct inode *inode, struct extent_status *es),
> +
> + TP_ARGS(inode, es)
> +);
> +
> +DECLARE_EVENT_CLASS(ext4__es_remove_extent,
> TP_PROTO(struct inode *inode, ext4_lblk_t lblk, ext4_lblk_t len),
>
> TP_ARGS(inode, lblk, len),
> @@ -2258,6 +2270,18 @@ TRACE_EVENT(ext4_es_remove_extent,
> __entry->lblk, __entry->len)
> );
>
> +DEFINE_EVENT(ext4__es_remove_extent, ext4_es_remove_extent_enter,
> + TP_PROTO(struct inode *inode, ext4_lblk_t lblk, ext4_lblk_t len),
> +
> + TP_ARGS(inode, lblk, len)
> +);
> +
> +DEFINE_EVENT(ext4__es_remove_extent, ext4_es_remove_extent_exit,
> + TP_PROTO(struct inode *inode, ext4_lblk_t lblk, ext4_lblk_t len),
> +
> + TP_ARGS(inode, lblk, len)
> +);
> +
> TRACE_EVENT(ext4_es_find_delayed_extent_range_enter,
> TP_PROTO(struct inode *inode, ext4_lblk_t lblk),
>
> @@ -2366,7 +2390,7 @@ TRACE_EVENT(ext4_es_lookup_extent_exit,
> show_extent_status(__entry->found ? __entry->status : 0))
> );
>
> -TRACE_EVENT(ext4_es_shrink_enter,
> +DECLARE_EVENT_CLASS(ext4__es_shrink_enter,
> TP_PROTO(struct super_block *sb, int nr_to_scan, int cache_cnt),
>
> TP_ARGS(sb, nr_to_scan, cache_cnt),
> @@ -2388,7 +2412,19 @@ TRACE_EVENT(ext4_es_shrink_enter,
> __entry->nr_to_scan, __entry->cache_cnt)
> );
>
> -TRACE_EVENT(ext4_es_shrink_exit,
> +DEFINE_EVENT(ext4__es_shrink_enter, ext4_es_shrink_count,
> + TP_PROTO(struct super_block *sb, int nr_to_scan, int cache_cnt),
> +
> + TP_ARGS(sb, nr_to_scan, cache_cnt)
> +);
> +
> +DEFINE_EVENT(ext4__es_shrink_enter, ext4_es_shrink_scan_enter,
> + TP_PROTO(struct super_block *sb, int nr_to_scan, int cache_cnt),
> +
> + TP_ARGS(sb, nr_to_scan, cache_cnt)
> +);
> +
> +TRACE_EVENT(ext4_es_shrink_scan_exit,
> TP_PROTO(struct super_block *sb, int shrunk_nr, int cache_cnt),
>
> TP_ARGS(sb, shrunk_nr, cache_cnt),
> --
> 1.7.9.7
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
Jan Kara <jack@...e.cz>
SUSE Labs, CR
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists