linux/drivers/md/bcache/sysfs.c
Coly Li 9aaf516546 bcache: make cutoff_writeback and cutoff_writeback_sync tunable
Currently the cutoff writeback and cutoff writeback sync thresholds are
defined by CUTOFF_WRITEBACK (40) and CUTOFF_WRITEBACK_SYNC (70) as
static values. Most of time these they work fine, but when people want
to do research on bcache writeback mode performance tuning, there is no
chance to modify the soft and hard cutoff writeback values.

This patch introduces two module parameters bch_cutoff_writeback_sync
and bch_cutoff_writeback which permit people to tune the values when
loading bcache.ko. If they are not specified by module loading, current
values CUTOFF_WRITEBACK_SYNC and CUTOFF_WRITEBACK will be used as
default and nothing changes.

When people want to tune this two values,
- cutoff_writeback can be set in range [1, 70]
- cutoff_writeback_sync can be set in range [1, 90]
- cutoff_writeback always <= cutoff_writeback_sync

The default values are strongly recommended to most of users for most of
workloads. Anyway, if people wants to take their own risk to do research
on new writeback cutoff tuning for their own workload, now they can make
it.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-13 08:15:54 -07:00

1065 lines
26 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* bcache sysfs interfaces
*
* Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
* Copyright 2012 Google, Inc.
*/
#include "bcache.h"
#include "sysfs.h"
#include "btree.h"
#include "request.h"
#include "writeback.h"
#include <linux/blkdev.h>
#include <linux/sort.h>
#include <linux/sched/clock.h>
/* Default is 0 ("writethrough") */
static const char * const bch_cache_modes[] = {
"writethrough",
"writeback",
"writearound",
"none",
NULL
};
/* Default is 0 ("auto") */
static const char * const bch_stop_on_failure_modes[] = {
"auto",
"always",
NULL
};
static const char * const cache_replacement_policies[] = {
"lru",
"fifo",
"random",
NULL
};
static const char * const error_actions[] = {
"unregister",
"panic",
NULL
};
write_attribute(attach);
write_attribute(detach);
write_attribute(unregister);
write_attribute(stop);
write_attribute(clear_stats);
write_attribute(trigger_gc);
write_attribute(prune_cache);
write_attribute(flash_vol_create);
read_attribute(bucket_size);
read_attribute(block_size);
read_attribute(nbuckets);
read_attribute(tree_depth);
read_attribute(root_usage_percent);
read_attribute(priority_stats);
read_attribute(btree_cache_size);
read_attribute(btree_cache_max_chain);
read_attribute(cache_available_percent);
read_attribute(written);
read_attribute(btree_written);
read_attribute(metadata_written);
read_attribute(active_journal_entries);
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_nodes);
read_attribute(btree_used_percent);
read_attribute(average_key_size);
read_attribute(dirty_data);
read_attribute(bset_tree_stats);
read_attribute(state);
read_attribute(cache_read_races);
read_attribute(reclaim);
read_attribute(flush_write);
read_attribute(retry_flush_write);
read_attribute(writeback_keys_done);
read_attribute(writeback_keys_failed);
read_attribute(io_errors);
read_attribute(congested);
read_attribute(cutoff_writeback);
read_attribute(cutoff_writeback_sync);
rw_attribute(congested_read_threshold_us);
rw_attribute(congested_write_threshold_us);
rw_attribute(sequential_cutoff);
rw_attribute(data_csum);
rw_attribute(cache_mode);
rw_attribute(stop_when_cache_set_failed);
rw_attribute(writeback_metadata);
rw_attribute(writeback_running);
rw_attribute(writeback_percent);
rw_attribute(writeback_delay);
rw_attribute(writeback_rate);
rw_attribute(writeback_rate_update_seconds);
rw_attribute(writeback_rate_i_term_inverse);
rw_attribute(writeback_rate_p_term_inverse);
rw_attribute(writeback_rate_minimum);
read_attribute(writeback_rate_debug);
read_attribute(stripe_size);
read_attribute(partial_stripes_expensive);
rw_attribute(synchronous);
rw_attribute(journal_delay_ms);
rw_attribute(io_disable);
rw_attribute(discard);
rw_attribute(running);
rw_attribute(label);
rw_attribute(readahead);
rw_attribute(errors);
rw_attribute(io_error_limit);
rw_attribute(io_error_halflife);
rw_attribute(verify);
rw_attribute(bypass_torture_test);
rw_attribute(key_merging_disabled);
rw_attribute(gc_always_rewrite);
rw_attribute(expensive_debug_checks);
rw_attribute(cache_replacement_policy);
rw_attribute(btree_shrinker_disabled);
rw_attribute(copy_gc_enabled);
rw_attribute(gc_after_writeback);
rw_attribute(size);
static ssize_t bch_snprint_string_list(char *buf,
size_t size,
const char * const list[],
size_t selected)
{
char *out = buf;
size_t i;
for (i = 0; list[i]; i++)
out += snprintf(out, buf + size - out,
i == selected ? "[%s] " : "%s ", list[i]);
out[-1] = '\n';
return out - buf;
}
SHOW(__bch_cached_dev)
{
struct cached_dev *dc = container_of(kobj, struct cached_dev,
disk.kobj);
char const *states[] = { "no cache", "clean", "dirty", "inconsistent" };
int wb = dc->writeback_running;
#define var(stat) (dc->stat)
if (attr == &sysfs_cache_mode)
return bch_snprint_string_list(buf, PAGE_SIZE,
bch_cache_modes,
BDEV_CACHE_MODE(&dc->sb));
if (attr == &sysfs_stop_when_cache_set_failed)
return bch_snprint_string_list(buf, PAGE_SIZE,
bch_stop_on_failure_modes,
dc->stop_when_cache_set_failed);
sysfs_printf(data_csum, "%i", dc->disk.data_csum);
var_printf(verify, "%i");
var_printf(bypass_torture_test, "%i");
var_printf(writeback_metadata, "%i");
var_printf(writeback_running, "%i");
var_print(writeback_delay);
var_print(writeback_percent);
sysfs_hprint(writeback_rate,
wb ? atomic_long_read(&dc->writeback_rate.rate) << 9 : 0);
sysfs_hprint(io_errors, atomic_read(&dc->io_errors));
sysfs_printf(io_error_limit, "%i", dc->error_limit);
sysfs_printf(io_disable, "%i", dc->io_disable);
var_print(writeback_rate_update_seconds);
var_print(writeback_rate_i_term_inverse);
var_print(writeback_rate_p_term_inverse);
var_print(writeback_rate_minimum);
if (attr == &sysfs_writeback_rate_debug) {
char rate[20];
char dirty[20];
char target[20];
char proportional[20];
char integral[20];
char change[20];
s64 next_io;
/*
* Except for dirty and target, other values should
* be 0 if writeback is not running.
*/
bch_hprint(rate,
wb ? atomic_long_read(&dc->writeback_rate.rate) << 9
: 0);
bch_hprint(dirty, bcache_dev_sectors_dirty(&dc->disk) << 9);
bch_hprint(target, dc->writeback_rate_target << 9);
bch_hprint(proportional,
wb ? dc->writeback_rate_proportional << 9 : 0);
bch_hprint(integral,
wb ? dc->writeback_rate_integral_scaled << 9 : 0);
bch_hprint(change, wb ? dc->writeback_rate_change << 9 : 0);
next_io = wb ? div64_s64(dc->writeback_rate.next-local_clock(),
NSEC_PER_MSEC) : 0;
return sprintf(buf,
"rate:\t\t%s/sec\n"
"dirty:\t\t%s\n"
"target:\t\t%s\n"
"proportional:\t%s\n"
"integral:\t%s\n"
"change:\t\t%s/sec\n"
"next io:\t%llims\n",
rate, dirty, target, proportional,
integral, change, next_io);
}
sysfs_hprint(dirty_data,
bcache_dev_sectors_dirty(&dc->disk) << 9);
sysfs_hprint(stripe_size, ((uint64_t)dc->disk.stripe_size) << 9);
var_printf(partial_stripes_expensive, "%u");
var_hprint(sequential_cutoff);
var_hprint(readahead);
sysfs_print(running, atomic_read(&dc->running));
sysfs_print(state, states[BDEV_STATE(&dc->sb)]);
if (attr == &sysfs_label) {
memcpy(buf, dc->sb.label, SB_LABEL_SIZE);
buf[SB_LABEL_SIZE + 1] = '\0';
strcat(buf, "\n");
return strlen(buf);
}
#undef var
return 0;
}
SHOW_LOCKED(bch_cached_dev)
STORE(__cached_dev)
{
struct cached_dev *dc = container_of(kobj, struct cached_dev,
disk.kobj);
ssize_t v;
struct cache_set *c;
struct kobj_uevent_env *env;
#define d_strtoul(var) sysfs_strtoul(var, dc->var)
#define d_strtoul_nonzero(var) sysfs_strtoul_clamp(var, dc->var, 1, INT_MAX)
#define d_strtoi_h(var) sysfs_hatoi(var, dc->var)
sysfs_strtoul(data_csum, dc->disk.data_csum);
d_strtoul(verify);
d_strtoul(bypass_torture_test);
d_strtoul(writeback_metadata);
d_strtoul(writeback_running);
d_strtoul(writeback_delay);
sysfs_strtoul_clamp(writeback_percent, dc->writeback_percent, 0, 40);
if (attr == &sysfs_writeback_rate) {
ssize_t ret;
long int v = atomic_long_read(&dc->writeback_rate.rate);
ret = strtoul_safe_clamp(buf, v, 1, INT_MAX);
if (!ret) {
atomic_long_set(&dc->writeback_rate.rate, v);
ret = size;
}
return ret;
}
sysfs_strtoul_clamp(writeback_rate_update_seconds,
dc->writeback_rate_update_seconds,
1, WRITEBACK_RATE_UPDATE_SECS_MAX);
d_strtoul(writeback_rate_i_term_inverse);
d_strtoul_nonzero(writeback_rate_p_term_inverse);
d_strtoul_nonzero(writeback_rate_minimum);
sysfs_strtoul_clamp(io_error_limit, dc->error_limit, 0, INT_MAX);
if (attr == &sysfs_io_disable) {
int v = strtoul_or_return(buf);
dc->io_disable = v ? 1 : 0;
}
d_strtoi_h(sequential_cutoff);
d_strtoi_h(readahead);
if (attr == &sysfs_clear_stats)
bch_cache_accounting_clear(&dc->accounting);
if (attr == &sysfs_running &&
strtoul_or_return(buf))
bch_cached_dev_run(dc);
if (attr == &sysfs_cache_mode) {
v = __sysfs_match_string(bch_cache_modes, -1, buf);
if (v < 0)
return v;
if ((unsigned int) v != BDEV_CACHE_MODE(&dc->sb)) {
SET_BDEV_CACHE_MODE(&dc->sb, v);
bch_write_bdev_super(dc, NULL);
}
}
if (attr == &sysfs_stop_when_cache_set_failed) {
v = __sysfs_match_string(bch_stop_on_failure_modes, -1, buf);
if (v < 0)
return v;
dc->stop_when_cache_set_failed = v;
}
if (attr == &sysfs_label) {
if (size > SB_LABEL_SIZE)
return -EINVAL;
memcpy(dc->sb.label, buf, size);
if (size < SB_LABEL_SIZE)
dc->sb.label[size] = '\0';
if (size && dc->sb.label[size - 1] == '\n')
dc->sb.label[size - 1] = '\0';
bch_write_bdev_super(dc, NULL);
if (dc->disk.c) {
memcpy(dc->disk.c->uuids[dc->disk.id].label,
buf, SB_LABEL_SIZE);
bch_uuid_write(dc->disk.c);
}
env = kzalloc(sizeof(struct kobj_uevent_env), GFP_KERNEL);
if (!env)
return -ENOMEM;
add_uevent_var(env, "DRIVER=bcache");
add_uevent_var(env, "CACHED_UUID=%pU", dc->sb.uuid),
add_uevent_var(env, "CACHED_LABEL=%s", buf);
kobject_uevent_env(&disk_to_dev(dc->disk.disk)->kobj,
KOBJ_CHANGE,
env->envp);
kfree(env);
}
if (attr == &sysfs_attach) {
uint8_t set_uuid[16];
if (bch_parse_uuid(buf, set_uuid) < 16)
return -EINVAL;
v = -ENOENT;
list_for_each_entry(c, &bch_cache_sets, list) {
v = bch_cached_dev_attach(dc, c, set_uuid);
if (!v)
return size;
}
if (v == -ENOENT)
pr_err("Can't attach %s: cache set not found", buf);
return v;
}
if (attr == &sysfs_detach && dc->disk.c)
bch_cached_dev_detach(dc);
if (attr == &sysfs_stop)
bcache_device_stop(&dc->disk);
return size;
}
STORE(bch_cached_dev)
{
struct cached_dev *dc = container_of(kobj, struct cached_dev,
disk.kobj);
mutex_lock(&bch_register_lock);
size = __cached_dev_store(kobj, attr, buf, size);
if (attr == &sysfs_writeback_running) {
/* dc->writeback_running changed in __cached_dev_store() */
if (IS_ERR_OR_NULL(dc->writeback_thread)) {
/*
* reject setting it to 1 via sysfs if writeback
* kthread is not created yet.
*/
if (dc->writeback_running) {
dc->writeback_running = false;
pr_err("%s: failed to run non-existent writeback thread",
dc->disk.disk->disk_name);
}
} else
/*
* writeback kthread will check if dc->writeback_running
* is true or false.
*/
bch_writeback_queue(dc);
}
if (attr == &sysfs_writeback_percent)
if (!test_and_set_bit(BCACHE_DEV_WB_RUNNING, &dc->disk.flags))
schedule_delayed_work(&dc->writeback_rate_update,
dc->writeback_rate_update_seconds * HZ);
mutex_unlock(&bch_register_lock);
return size;
}
static struct attribute *bch_cached_dev_files[] = {
&sysfs_attach,
&sysfs_detach,
&sysfs_stop,
#if 0
&sysfs_data_csum,
#endif
&sysfs_cache_mode,
&sysfs_stop_when_cache_set_failed,
&sysfs_writeback_metadata,
&sysfs_writeback_running,
&sysfs_writeback_delay,
&sysfs_writeback_percent,
&sysfs_writeback_rate,
&sysfs_writeback_rate_update_seconds,
&sysfs_writeback_rate_i_term_inverse,
&sysfs_writeback_rate_p_term_inverse,
&sysfs_writeback_rate_minimum,
&sysfs_writeback_rate_debug,
&sysfs_errors,
&sysfs_io_error_limit,
&sysfs_io_disable,
&sysfs_dirty_data,
&sysfs_stripe_size,
&sysfs_partial_stripes_expensive,
&sysfs_sequential_cutoff,
&sysfs_clear_stats,
&sysfs_running,
&sysfs_state,
&sysfs_label,
&sysfs_readahead,
#ifdef CONFIG_BCACHE_DEBUG
&sysfs_verify,
&sysfs_bypass_torture_test,
#endif
NULL
};
KTYPE(bch_cached_dev);
SHOW(bch_flash_dev)
{
struct bcache_device *d = container_of(kobj, struct bcache_device,
kobj);
struct uuid_entry *u = &d->c->uuids[d->id];
sysfs_printf(data_csum, "%i", d->data_csum);
sysfs_hprint(size, u->sectors << 9);
if (attr == &sysfs_label) {
memcpy(buf, u->label, SB_LABEL_SIZE);
buf[SB_LABEL_SIZE + 1] = '\0';
strcat(buf, "\n");
return strlen(buf);
}
return 0;
}
STORE(__bch_flash_dev)
{
struct bcache_device *d = container_of(kobj, struct bcache_device,
kobj);
struct uuid_entry *u = &d->c->uuids[d->id];
sysfs_strtoul(data_csum, d->data_csum);
if (attr == &sysfs_size) {
uint64_t v;
strtoi_h_or_return(buf, v);
u->sectors = v >> 9;
bch_uuid_write(d->c);
set_capacity(d->disk, u->sectors);
}
if (attr == &sysfs_label) {
memcpy(u->label, buf, SB_LABEL_SIZE);
bch_uuid_write(d->c);
}
if (attr == &sysfs_unregister) {
set_bit(BCACHE_DEV_DETACHING, &d->flags);
bcache_device_stop(d);
}
return size;
}
STORE_LOCKED(bch_flash_dev)
static struct attribute *bch_flash_dev_files[] = {
&sysfs_unregister,
#if 0
&sysfs_data_csum,
#endif
&sysfs_label,
&sysfs_size,
NULL
};
KTYPE(bch_flash_dev);
struct bset_stats_op {
struct btree_op op;
size_t nodes;
struct bset_stats stats;
};
static int bch_btree_bset_stats(struct btree_op *b_op, struct btree *b)
{
struct bset_stats_op *op = container_of(b_op, struct bset_stats_op, op);
op->nodes++;
bch_btree_keys_stats(&b->keys, &op->stats);
return MAP_CONTINUE;
}
static int bch_bset_print_stats(struct cache_set *c, char *buf)
{
struct bset_stats_op op;
int ret;
memset(&op, 0, sizeof(op));
bch_btree_op_init(&op.op, -1);
ret = bch_btree_map_nodes(&op.op, c, &ZERO_KEY, bch_btree_bset_stats);
if (ret < 0)
return ret;
return snprintf(buf, PAGE_SIZE,
"btree nodes: %zu\n"
"written sets: %zu\n"
"unwritten sets: %zu\n"
"written key bytes: %zu\n"
"unwritten key bytes: %zu\n"
"floats: %zu\n"
"failed: %zu\n",
op.nodes,
op.stats.sets_written, op.stats.sets_unwritten,
op.stats.bytes_written, op.stats.bytes_unwritten,
op.stats.floats, op.stats.failed);
}
static unsigned int bch_root_usage(struct cache_set *c)
{
unsigned int bytes = 0;
struct bkey *k;
struct btree *b;
struct btree_iter iter;
goto lock_root;
do {
rw_unlock(false, b);
lock_root:
b = c->root;
rw_lock(false, b, b->level);
} while (b != c->root);
for_each_key_filter(&b->keys, k, &iter, bch_ptr_bad)
bytes += bkey_bytes(k);
rw_unlock(false, b);
return (bytes * 100) / btree_bytes(c);
}
static size_t bch_cache_size(struct cache_set *c)
{
size_t ret = 0;
struct btree *b;
mutex_lock(&c->bucket_lock);
list_for_each_entry(b, &c->btree_cache, list)
ret += 1 << (b->keys.page_order + PAGE_SHIFT);
mutex_unlock(&c->bucket_lock);
return ret;
}
static unsigned int bch_cache_max_chain(struct cache_set *c)
{
unsigned int ret = 0;
struct hlist_head *h;
mutex_lock(&c->bucket_lock);
for (h = c->bucket_hash;
h < c->bucket_hash + (1 << BUCKET_HASH_BITS);
h++) {
unsigned int i = 0;
struct hlist_node *p;
hlist_for_each(p, h)
i++;
ret = max(ret, i);
}
mutex_unlock(&c->bucket_lock);
return ret;
}
static unsigned int bch_btree_used(struct cache_set *c)
{
return div64_u64(c->gc_stats.key_bytes * 100,
(c->gc_stats.nodes ?: 1) * btree_bytes(c));
}
static unsigned int bch_average_key_size(struct cache_set *c)
{
return c->gc_stats.nkeys
? div64_u64(c->gc_stats.data, c->gc_stats.nkeys)
: 0;
}
SHOW(__bch_cache_set)
{
struct cache_set *c = container_of(kobj, struct cache_set, kobj);
sysfs_print(synchronous, CACHE_SYNC(&c->sb));
sysfs_print(journal_delay_ms, c->journal_delay_ms);
sysfs_hprint(bucket_size, bucket_bytes(c));
sysfs_hprint(block_size, block_bytes(c));
sysfs_print(tree_depth, c->root->level);
sysfs_print(root_usage_percent, bch_root_usage(c));
sysfs_hprint(btree_cache_size, bch_cache_size(c));
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(btree_used_percent, bch_btree_used(c));
sysfs_print(btree_nodes, c->gc_stats.nodes);
sysfs_hprint(average_key_size, bch_average_key_size(c));
sysfs_print(cache_read_races,
atomic_long_read(&c->cache_read_races));
sysfs_print(reclaim,
atomic_long_read(&c->reclaim));
sysfs_print(flush_write,
atomic_long_read(&c->flush_write));
sysfs_print(retry_flush_write,
atomic_long_read(&c->retry_flush_write));
sysfs_print(writeback_keys_done,
atomic_long_read(&c->writeback_keys_done));
sysfs_print(writeback_keys_failed,
atomic_long_read(&c->writeback_keys_failed));
if (attr == &sysfs_errors)
return bch_snprint_string_list(buf, PAGE_SIZE, error_actions,
c->on_error);
/* See count_io_errors for why 88 */
sysfs_print(io_error_halflife, c->error_decay * 88);
sysfs_print(io_error_limit, c->error_limit);
sysfs_hprint(congested,
((uint64_t) bch_get_congested(c)) << 9);
sysfs_print(congested_read_threshold_us,
c->congested_read_threshold_us);
sysfs_print(congested_write_threshold_us,
c->congested_write_threshold_us);
sysfs_print(cutoff_writeback, bch_cutoff_writeback);
sysfs_print(cutoff_writeback_sync, bch_cutoff_writeback_sync);
sysfs_print(active_journal_entries, fifo_used(&c->journal.pin));
sysfs_printf(verify, "%i", c->verify);
sysfs_printf(key_merging_disabled, "%i", c->key_merging_disabled);
sysfs_printf(expensive_debug_checks,
"%i", c->expensive_debug_checks);
sysfs_printf(gc_always_rewrite, "%i", c->gc_always_rewrite);
sysfs_printf(btree_shrinker_disabled, "%i", c->shrinker_disabled);
sysfs_printf(copy_gc_enabled, "%i", c->copy_gc_enabled);
sysfs_printf(gc_after_writeback, "%i", c->gc_after_writeback);
sysfs_printf(io_disable, "%i",
test_bit(CACHE_SET_IO_DISABLE, &c->flags));
if (attr == &sysfs_bset_tree_stats)
return bch_bset_print_stats(c, buf);
return 0;
}
SHOW_LOCKED(bch_cache_set)
STORE(__bch_cache_set)
{
struct cache_set *c = container_of(kobj, struct cache_set, kobj);
ssize_t v;
if (attr == &sysfs_unregister)
bch_cache_set_unregister(c);
if (attr == &sysfs_stop)
bch_cache_set_stop(c);
if (attr == &sysfs_synchronous) {
bool sync = strtoul_or_return(buf);
if (sync != CACHE_SYNC(&c->sb)) {
SET_CACHE_SYNC(&c->sb, sync);
bcache_write_super(c);
}
}
if (attr == &sysfs_flash_vol_create) {
int r;
uint64_t v;
strtoi_h_or_return(buf, v);
r = bch_flash_dev_create(c, v);
if (r)
return r;
}
if (attr == &sysfs_clear_stats) {
atomic_long_set(&c->writeback_keys_done, 0);
atomic_long_set(&c->writeback_keys_failed, 0);
memset(&c->gc_stats, 0, sizeof(struct gc_stat));
bch_cache_accounting_clear(&c->accounting);
}
if (attr == &sysfs_trigger_gc)
force_wake_up_gc(c);
if (attr == &sysfs_prune_cache) {
struct shrink_control sc;
sc.gfp_mask = GFP_KERNEL;
sc.nr_to_scan = strtoul_or_return(buf);
c->shrink.scan_objects(&c->shrink, &sc);
}
sysfs_strtoul(congested_read_threshold_us,
c->congested_read_threshold_us);
sysfs_strtoul(congested_write_threshold_us,
c->congested_write_threshold_us);
if (attr == &sysfs_errors) {
v = __sysfs_match_string(error_actions, -1, buf);
if (v < 0)
return v;
c->on_error = v;
}
if (attr == &sysfs_io_error_limit)
c->error_limit = strtoul_or_return(buf);
/* See count_io_errors() for why 88 */
if (attr == &sysfs_io_error_halflife)
c->error_decay = strtoul_or_return(buf) / 88;
if (attr == &sysfs_io_disable) {
v = strtoul_or_return(buf);
if (v) {
if (test_and_set_bit(CACHE_SET_IO_DISABLE,
&c->flags))
pr_warn("CACHE_SET_IO_DISABLE already set");
} else {
if (!test_and_clear_bit(CACHE_SET_IO_DISABLE,
&c->flags))
pr_warn("CACHE_SET_IO_DISABLE already cleared");
}
}
sysfs_strtoul(journal_delay_ms, c->journal_delay_ms);
sysfs_strtoul(verify, c->verify);
sysfs_strtoul(key_merging_disabled, c->key_merging_disabled);
sysfs_strtoul(expensive_debug_checks, c->expensive_debug_checks);
sysfs_strtoul(gc_always_rewrite, c->gc_always_rewrite);
sysfs_strtoul(btree_shrinker_disabled, c->shrinker_disabled);
sysfs_strtoul(copy_gc_enabled, c->copy_gc_enabled);
/*
* write gc_after_writeback here may overwrite an already set
* BCH_DO_AUTO_GC, it doesn't matter because this flag will be
* set in next chance.
*/
sysfs_strtoul_clamp(gc_after_writeback, c->gc_after_writeback, 0, 1);
return size;
}
STORE_LOCKED(bch_cache_set)
SHOW(bch_cache_set_internal)
{
struct cache_set *c = container_of(kobj, struct cache_set, internal);
return bch_cache_set_show(&c->kobj, attr, buf);
}
STORE(bch_cache_set_internal)
{
struct cache_set *c = container_of(kobj, struct cache_set, internal);
return bch_cache_set_store(&c->kobj, attr, buf, size);
}
static void bch_cache_set_internal_release(struct kobject *k)
{
}
static struct attribute *bch_cache_set_files[] = {
&sysfs_unregister,
&sysfs_stop,
&sysfs_synchronous,
&sysfs_journal_delay_ms,
&sysfs_flash_vol_create,
&sysfs_bucket_size,
&sysfs_block_size,
&sysfs_tree_depth,
&sysfs_root_usage_percent,
&sysfs_btree_cache_size,
&sysfs_cache_available_percent,
&sysfs_average_key_size,
&sysfs_errors,
&sysfs_io_error_limit,
&sysfs_io_error_halflife,
&sysfs_congested,
&sysfs_congested_read_threshold_us,
&sysfs_congested_write_threshold_us,
&sysfs_clear_stats,
NULL
};
KTYPE(bch_cache_set);
static struct attribute *bch_cache_set_internal_files[] = {
&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_nodes,
&sysfs_btree_used_percent,
&sysfs_btree_cache_max_chain,
&sysfs_bset_tree_stats,
&sysfs_cache_read_races,
&sysfs_reclaim,
&sysfs_flush_write,
&sysfs_retry_flush_write,
&sysfs_writeback_keys_done,
&sysfs_writeback_keys_failed,
&sysfs_trigger_gc,
&sysfs_prune_cache,
#ifdef CONFIG_BCACHE_DEBUG
&sysfs_verify,
&sysfs_key_merging_disabled,
&sysfs_expensive_debug_checks,
#endif
&sysfs_gc_always_rewrite,
&sysfs_btree_shrinker_disabled,
&sysfs_copy_gc_enabled,
&sysfs_gc_after_writeback,
&sysfs_io_disable,
&sysfs_cutoff_writeback,
&sysfs_cutoff_writeback_sync,
NULL
};
KTYPE(bch_cache_set_internal);
static int __bch_cache_cmp(const void *l, const void *r)
{
return *((uint16_t *)r) - *((uint16_t *)l);
}
SHOW(__bch_cache)
{
struct cache *ca = container_of(kobj, struct cache, kobj);
sysfs_hprint(bucket_size, bucket_bytes(ca));
sysfs_hprint(block_size, block_bytes(ca));
sysfs_print(nbuckets, ca->sb.nbuckets);
sysfs_print(discard, ca->discard);
sysfs_hprint(written, atomic_long_read(&ca->sectors_written) << 9);
sysfs_hprint(btree_written,
atomic_long_read(&ca->btree_sectors_written) << 9);
sysfs_hprint(metadata_written,
(atomic_long_read(&ca->meta_sectors_written) +
atomic_long_read(&ca->btree_sectors_written)) << 9);
sysfs_print(io_errors,
atomic_read(&ca->io_errors) >> IO_ERROR_SHIFT);
if (attr == &sysfs_cache_replacement_policy)
return bch_snprint_string_list(buf, PAGE_SIZE,
cache_replacement_policies,
CACHE_REPLACEMENT(&ca->sb));
if (attr == &sysfs_priority_stats) {
struct bucket *b;
size_t n = ca->sb.nbuckets, i;
size_t unused = 0, available = 0, dirty = 0, meta = 0;
uint64_t sum = 0;
/* Compute 31 quantiles */
uint16_t q[31], *p, *cached;
ssize_t ret;
cached = p = vmalloc(array_size(sizeof(uint16_t),
ca->sb.nbuckets));
if (!p)
return -ENOMEM;
mutex_lock(&ca->set->bucket_lock);
for_each_bucket(b, ca) {
if (!GC_SECTORS_USED(b))
unused++;
if (GC_MARK(b) == GC_MARK_RECLAIMABLE)
available++;
if (GC_MARK(b) == GC_MARK_DIRTY)
dirty++;
if (GC_MARK(b) == GC_MARK_METADATA)
meta++;
}
for (i = ca->sb.first_bucket; i < n; i++)
p[i] = ca->buckets[i].prio;
mutex_unlock(&ca->set->bucket_lock);
sort(p, n, sizeof(uint16_t), __bch_cache_cmp, NULL);
while (n &&
!cached[n - 1])
--n;
unused = ca->sb.nbuckets - n;
while (cached < p + n &&
*cached == BTREE_PRIO)
cached++, n--;
for (i = 0; i < n; i++)
sum += INITIAL_PRIO - cached[i];
if (n)
do_div(sum, n);
for (i = 0; i < ARRAY_SIZE(q); i++)
q[i] = INITIAL_PRIO - cached[n * (i + 1) /
(ARRAY_SIZE(q) + 1)];
vfree(p);
ret = scnprintf(buf, PAGE_SIZE,
"Unused: %zu%%\n"
"Clean: %zu%%\n"
"Dirty: %zu%%\n"
"Metadata: %zu%%\n"
"Average: %llu\n"
"Sectors per Q: %zu\n"
"Quantiles: [",
unused * 100 / (size_t) ca->sb.nbuckets,
available * 100 / (size_t) ca->sb.nbuckets,
dirty * 100 / (size_t) ca->sb.nbuckets,
meta * 100 / (size_t) ca->sb.nbuckets, sum,
n * ca->sb.bucket_size / (ARRAY_SIZE(q) + 1));
for (i = 0; i < ARRAY_SIZE(q); i++)
ret += scnprintf(buf + ret, PAGE_SIZE - ret,
"%u ", q[i]);
ret--;
ret += scnprintf(buf + ret, PAGE_SIZE - ret, "]\n");
return ret;
}
return 0;
}
SHOW_LOCKED(bch_cache)
STORE(__bch_cache)
{
struct cache *ca = container_of(kobj, struct cache, kobj);
ssize_t v;
if (attr == &sysfs_discard) {
bool v = strtoul_or_return(buf);
if (blk_queue_discard(bdev_get_queue(ca->bdev)))
ca->discard = v;
if (v != CACHE_DISCARD(&ca->sb)) {
SET_CACHE_DISCARD(&ca->sb, v);
bcache_write_super(ca->set);
}
}
if (attr == &sysfs_cache_replacement_policy) {
v = __sysfs_match_string(cache_replacement_policies, -1, buf);
if (v < 0)
return v;
if ((unsigned int) v != CACHE_REPLACEMENT(&ca->sb)) {
mutex_lock(&ca->set->bucket_lock);
SET_CACHE_REPLACEMENT(&ca->sb, v);
mutex_unlock(&ca->set->bucket_lock);
bcache_write_super(ca->set);
}
}
if (attr == &sysfs_clear_stats) {
atomic_long_set(&ca->sectors_written, 0);
atomic_long_set(&ca->btree_sectors_written, 0);
atomic_long_set(&ca->meta_sectors_written, 0);
atomic_set(&ca->io_count, 0);
atomic_set(&ca->io_errors, 0);
}
return size;
}
STORE_LOCKED(bch_cache)
static struct attribute *bch_cache_files[] = {
&sysfs_bucket_size,
&sysfs_block_size,
&sysfs_nbuckets,
&sysfs_priority_stats,
&sysfs_discard,
&sysfs_written,
&sysfs_btree_written,
&sysfs_metadata_written,
&sysfs_io_errors,
&sysfs_clear_stats,
&sysfs_cache_replacement_policy,
NULL
};
KTYPE(bch_cache);