On Fri, Jan 26, 2024 at 05:06:55PM -0500, Kent Overstreet wrote:
> delete bcache's time stats code, convert to newer version from bcachefs.
>
> example output:
>
> root@moria-kvm:/sys/fs/bcache/bdaedb8c-4554-4dd2-87e4-276e51eb47cc# cat internal/btree_sort_times
> count: 6414
> since mount recent
> duration of events
> min: 440 ns
> max: 1102 us
> total: 674 ms
> mean: 105 us 102 us
> stddev: 101 us 88 us
> time between events
> min: 881 ns
> max: 3 s
> mean: 7 ms 6 ms
> stddev: 52 ms 6 ms
>
> Cc: Coly Li <colyli@xxxxxxx>
> Cc: linux-bcache@xxxxxxxxxxxxxxx
> Signed-off-by: Kent Overstreet <kent.overstreet@xxxxxxxxx>
Acked-by: Coly Li <colyli@xxxxxxx>
Thanks.
Coly Li
> ---
> drivers/md/bcache/Kconfig | 1 +
> drivers/md/bcache/bcache.h | 1 +
> drivers/md/bcache/bset.c | 6 +++--
> drivers/md/bcache/bset.h | 1 +
> drivers/md/bcache/btree.c | 6 ++---
> drivers/md/bcache/super.c | 7 +++++
> drivers/md/bcache/sysfs.c | 25 +++++++++---------
> drivers/md/bcache/util.c | 30 ----------------------
> drivers/md/bcache/util.h | 52 +++++---------------------------------
> 9 files changed, 37 insertions(+), 92 deletions(-)
>
> diff --git a/drivers/md/bcache/Kconfig b/drivers/md/bcache/Kconfig
> index b2d10063d35f..7ea057983d3d 100644
> --- a/drivers/md/bcache/Kconfig
> +++ b/drivers/md/bcache/Kconfig
> @@ -5,6 +5,7 @@ config BCACHE
> select BLOCK_HOLDER_DEPRECATED if SYSFS
> select CRC64
> select CLOSURES
> + select TIME_STATS
> help
> Allows a block device to be used as cache for other devices; uses
> a btree for indexing and the layout is optimized for SSDs.
> diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
> index 6ae2329052c9..76e7b494c394 100644
> --- a/drivers/md/bcache/bcache.h
> +++ b/drivers/md/bcache/bcache.h
> @@ -186,6 +186,7 @@
> #include <linux/rbtree.h>
> #include <linux/rwsem.h>
> #include <linux/refcount.h>
> +#include <linux/time_stats.h>
> #include <linux/types.h>
> #include <linux/workqueue.h>
> #include <linux/kthread.h>
> diff --git a/drivers/md/bcache/bset.c b/drivers/md/bcache/bset.c
> index 2bba4d6aaaa2..31c08d4ab83b 100644
> --- a/drivers/md/bcache/bset.c
> +++ b/drivers/md/bcache/bset.c
> @@ -1177,6 +1177,7 @@ struct bkey *bch_btree_iter_next_filter(struct btree_iter *iter,
>
> void bch_bset_sort_state_free(struct bset_sort_state *state)
> {
> + time_stats_exit(&state->time);
> mempool_exit(&state->pool);
> }
>
> @@ -1184,6 +1185,7 @@ int bch_bset_sort_state_init(struct bset_sort_state *state,
> unsigned int page_order)
> {
> spin_lock_init(&state->time.lock);
> + time_stats_init(&state->time);
>
> state->page_order = page_order;
> state->crit_factor = int_sqrt(1 << page_order);
> @@ -1286,7 +1288,7 @@ static void __btree_sort(struct btree_keys *b, struct btree_iter *iter,
> bch_bset_build_written_tree(b);
>
> if (!start)
> - bch_time_stats_update(&state->time, start_time);
> + time_stats_update(&state->time, start_time);
> }
>
> void bch_btree_sort_partial(struct btree_keys *b, unsigned int start,
> @@ -1329,7 +1331,7 @@ void bch_btree_sort_into(struct btree_keys *b, struct btree_keys *new,
>
> btree_mergesort(b, new->set->data, &iter, false, true);
>
> - bch_time_stats_update(&state->time, start_time);
> + time_stats_update(&state->time, start_time);
>
> new->set->size = 0; // XXX: why?
> }
> diff --git a/drivers/md/bcache/bset.h b/drivers/md/bcache/bset.h
> index d795c84246b0..13e524ad7783 100644
> --- a/drivers/md/bcache/bset.h
> +++ b/drivers/md/bcache/bset.h
> @@ -3,6 +3,7 @@
> #define _BCACHE_BSET_H
>
> #include <linux/kernel.h>
> +#include <linux/time_stats.h>
> #include <linux/types.h>
>
> #include "bcache_ondisk.h"
> diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c
> index 196cdacce38f..0ed337c5f0dc 100644
> --- a/drivers/md/bcache/btree.c
> +++ b/drivers/md/bcache/btree.c
> @@ -270,7 +270,7 @@ static void bch_btree_node_read(struct btree *b)
> goto err;
>
> bch_btree_node_read_done(b);
> - bch_time_stats_update(&b->c->btree_read_time, start_time);
> + time_stats_update(&b->c->btree_read_time, start_time);
>
> return;
> err:
> @@ -1852,7 +1852,7 @@ static void bch_btree_gc(struct cache_set *c)
> bch_btree_gc_finish(c);
> wake_up_allocators(c);
>
> - bch_time_stats_update(&c->btree_gc_time, start_time);
> + time_stats_update(&c->btree_gc_time, start_time);
>
> stats.key_bytes *= sizeof(uint64_t);
> stats.data <<= 9;
> @@ -2343,7 +2343,7 @@ static int btree_split(struct btree *b, struct btree_op *op,
> btree_node_free(b);
> rw_unlock(true, n1);
>
> - bch_time_stats_update(&b->c->btree_split_time, start_time);
> + time_stats_update(&b->c->btree_split_time, start_time);
>
> return 0;
> err_free2:
> diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
> index dc3f50f69714..625e4883299c 100644
> --- a/drivers/md/bcache/super.c
> +++ b/drivers/md/bcache/super.c
> @@ -1676,6 +1676,9 @@ static CLOSURE_CALLBACK(cache_set_free)
>
> debugfs_remove(c->debug);
>
> + time_stats_exit(&c->btree_read_time);
> + time_stats_exit(&c->btree_split_time);
> + time_stats_exit(&c->btree_gc_time);
> bch_open_buckets_free(c);
> bch_btree_cache_free(c);
> bch_journal_free(c);
> @@ -1913,6 +1916,10 @@ struct cache_set *bch_cache_set_alloc(struct cache_sb *sb)
> INIT_LIST_HEAD(&c->btree_cache_freed);
> INIT_LIST_HEAD(&c->data_buckets);
>
> + time_stats_init(&c->btree_gc_time);
> + time_stats_init(&c->btree_split_time);
> + time_stats_init(&c->btree_read_time);
> +
> iter_size = ((meta_bucket_pages(sb) * PAGE_SECTORS) / sb->block_size + 1) *
> sizeof(struct btree_iter_set);
>
> diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
> index a438efb66069..01cc5c632f08 100644
> --- a/drivers/md/bcache/sysfs.c
> +++ b/drivers/md/bcache/sysfs.c
> @@ -14,6 +14,7 @@
> #include "features.h"
>
> #include <linux/blkdev.h>
> +#include <linux/seq_buf.h>
> #include <linux/sort.h>
> #include <linux/sched/clock.h>
>
> @@ -79,10 +80,10 @@ read_attribute(active_journal_entries);
> read_attribute(backing_dev_name);
> read_attribute(backing_dev_uuid);
>
> -sysfs_time_stats_attribute(btree_gc, sec, ms);
> -sysfs_time_stats_attribute(btree_split, sec, us);
> -sysfs_time_stats_attribute(btree_sort, ms, us);
> -sysfs_time_stats_attribute(btree_read, ms, us);
> +read_attribute(btree_gc_times);
> +read_attribute(btree_split_times);
> +read_attribute(btree_sort_times);
> +read_attribute(btree_read_times);
>
> read_attribute(btree_nodes);
> read_attribute(btree_used_percent);
> @@ -743,10 +744,10 @@ SHOW(__bch_cache_set)
> sysfs_print(btree_cache_max_chain, bch_cache_max_chain(c));
> sysfs_print(cache_available_percent, 100 - c->gc_stats.in_use);
>
> - sysfs_print_time_stats(&c->btree_gc_time, btree_gc, sec, ms);
> - sysfs_print_time_stats(&c->btree_split_time, btree_split, sec, us);
> - sysfs_print_time_stats(&c->sort.time, btree_sort, ms, us);
> - sysfs_print_time_stats(&c->btree_read_time, btree_read, ms, us);
> + sysfs_print_time_stats(&c->btree_gc_time, btree_gc_times);
> + sysfs_print_time_stats(&c->btree_split_time, btree_split_times);
> + sysfs_print_time_stats(&c->sort.time, btree_sort_times);
> + sysfs_print_time_stats(&c->btree_read_time, btree_read_times);
>
> sysfs_print(btree_used_percent, bch_btree_used(c));
> sysfs_print(btree_nodes, c->gc_stats.nodes);
> @@ -989,10 +990,10 @@ KTYPE(bch_cache_set);
> static struct attribute *bch_cache_set_internal_attrs[] = {
> &sysfs_active_journal_entries,
>
> - sysfs_time_stats_attribute_list(btree_gc, sec, ms)
> - sysfs_time_stats_attribute_list(btree_split, sec, us)
> - sysfs_time_stats_attribute_list(btree_sort, ms, us)
> - sysfs_time_stats_attribute_list(btree_read, ms, us)
> + &sysfs_btree_gc_times,
> + &sysfs_btree_split_times,
> + &sysfs_btree_sort_times,
> + &sysfs_btree_read_times,
>
> &sysfs_btree_nodes,
> &sysfs_btree_used_percent,
> diff --git a/drivers/md/bcache/util.c b/drivers/md/bcache/util.c
> index ae380bc3992e..95282bf0f9a7 100644
> --- a/drivers/md/bcache/util.c
> +++ b/drivers/md/bcache/util.c
> @@ -160,36 +160,6 @@ int bch_parse_uuid(const char *s, char *uuid)
> return i;
> }
>
> -void bch_time_stats_update(struct time_stats *stats, uint64_t start_time)
> -{
> - uint64_t now, duration, last;
> -
> - spin_lock(&stats->lock);
> -
> - now = local_clock();
> - duration = time_after64(now, start_time)
> - ? now - start_time : 0;
> - last = time_after64(now, stats->last)
> - ? now - stats->last : 0;
> -
> - stats->max_duration = max(stats->max_duration, duration);
> -
> - if (stats->last) {
> - ewma_add(stats->average_duration, duration, 8, 8);
> -
> - if (stats->average_frequency)
> - ewma_add(stats->average_frequency, last, 8, 8);
> - else
> - stats->average_frequency = last << 8;
> - } else {
> - stats->average_duration = duration << 8;
> - }
> -
> - stats->last = now ?: 1;
> -
> - spin_unlock(&stats->lock);
> -}
> -
> /**
> * bch_next_delay() - update ratelimiting statistics and calculate next delay
> * @d: the struct bch_ratelimit to update
> diff --git a/drivers/md/bcache/util.h b/drivers/md/bcache/util.h
> index f61ab1bada6c..6fcb9db4f50d 100644
> --- a/drivers/md/bcache/util.h
> +++ b/drivers/md/bcache/util.h
> @@ -344,20 +344,6 @@ ssize_t bch_hprint(char *buf, int64_t v);
> bool bch_is_zero(const char *p, size_t n);
> int bch_parse_uuid(const char *s, char *uuid);
>
> -struct time_stats {
> - spinlock_t lock;
> - /*
> - * all fields are in nanoseconds, averages are ewmas stored left shifted
> - * by 8
> - */
> - uint64_t max_duration;
> - uint64_t average_duration;
> - uint64_t average_frequency;
> - uint64_t last;
> -};
> -
> -void bch_time_stats_update(struct time_stats *stats, uint64_t time);
> -
> static inline unsigned int local_clock_us(void)
> {
> return local_clock() >> 10;
> @@ -372,40 +358,16 @@ static inline unsigned int local_clock_us(void)
> sysfs_print(name ## _ ## stat ## _ ## units, \
> div_u64((stats)->stat >> 8, NSEC_PER_ ## units))
>
> -#define sysfs_print_time_stats(stats, name, \
> - frequency_units, \
> - duration_units) \
> +#define sysfs_print_time_stats(stats, name) \
> do { \
> - __print_time_stat(stats, name, \
> - average_frequency, frequency_units); \
> - __print_time_stat(stats, name, \
> - average_duration, duration_units); \
> - sysfs_print(name ## _ ##max_duration ## _ ## duration_units, \
> - div_u64((stats)->max_duration, \
> - NSEC_PER_ ## duration_units)); \
> - \
> - sysfs_print(name ## _last_ ## frequency_units, (stats)->last \
> - ? div_s64(local_clock() - (stats)->last, \
> - NSEC_PER_ ## frequency_units) \
> - : -1LL); \
> + if (attr == &sysfs_##name) { \
> + struct seq_buf seq; \
> + seq_buf_init(&seq, buf, PAGE_SIZE); \
> + time_stats_to_seq_buf(&seq, stats); \
> + return seq.len; \
> + } \
> } while (0)
>
> -#define sysfs_time_stats_attribute(name, \
> - frequency_units, \
> - duration_units) \
> -read_attribute(name ## _average_frequency_ ## frequency_units); \
> -read_attribute(name ## _average_duration_ ## duration_units); \
> -read_attribute(name ## _max_duration_ ## duration_units); \
> -read_attribute(name ## _last_ ## frequency_units)
> -
> -#define sysfs_time_stats_attribute_list(name, \
> - frequency_units, \
> - duration_units) \
> -&sysfs_ ## name ## _average_frequency_ ## frequency_units, \
> -&sysfs_ ## name ## _average_duration_ ## duration_units, \
> -&sysfs_ ## name ## _max_duration_ ## duration_units, \
> -&sysfs_ ## name ## _last_ ## frequency_units,
> -
> #define ewma_add(ewma, val, weight, factor) \
> ({ \
> (ewma) *= (weight) - 1; \
> --
> 2.43.0
>
