mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-25 21:24:08 +08:00
4f44657d74
The current blkio.throttle.io_service_bytes_recursive doesn't
work correctly.
As an example, for the following blkcg hierarchy:
(Made 1GB READ in test1, 512MB READ in test2)
test
/ \
test1 test2
$ head -n 1 test/test1/blkio.throttle.io_service_bytes_recursive
8:0 Read 1073684480
$ head -n 1 test/test2/blkio.throttle.io_service_bytes_recursive
8:0 Read 537448448
$ head -n 1 test/blkio.throttle.io_service_bytes_recursive
8:0 Read 537448448
Clearly, above data of "test" reflects "test2" not "test1"+"test2".
Do the correct summary in blkg_rwstat_recursive_sum().
Signed-off-by: Xunlei Pang <xlpang@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
131 lines
3.4 KiB
C
131 lines
3.4 KiB
C
/* SPDX-License-Identifier: GPL-2.0
|
|
*
|
|
* Legacy blkg rwstat helpers enabled by CONFIG_BLK_CGROUP_RWSTAT.
|
|
* Do not use in new code.
|
|
*/
|
|
#include "blk-cgroup-rwstat.h"
|
|
|
|
int blkg_rwstat_init(struct blkg_rwstat *rwstat, gfp_t gfp)
|
|
{
|
|
int i, ret;
|
|
|
|
for (i = 0; i < BLKG_RWSTAT_NR; i++) {
|
|
ret = percpu_counter_init(&rwstat->cpu_cnt[i], 0, gfp);
|
|
if (ret) {
|
|
while (--i >= 0)
|
|
percpu_counter_destroy(&rwstat->cpu_cnt[i]);
|
|
return ret;
|
|
}
|
|
atomic64_set(&rwstat->aux_cnt[i], 0);
|
|
}
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(blkg_rwstat_init);
|
|
|
|
void blkg_rwstat_exit(struct blkg_rwstat *rwstat)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < BLKG_RWSTAT_NR; i++)
|
|
percpu_counter_destroy(&rwstat->cpu_cnt[i]);
|
|
}
|
|
EXPORT_SYMBOL_GPL(blkg_rwstat_exit);
|
|
|
|
/**
|
|
* __blkg_prfill_rwstat - prfill helper for a blkg_rwstat
|
|
* @sf: seq_file to print to
|
|
* @pd: policy private data of interest
|
|
* @rwstat: rwstat to print
|
|
*
|
|
* Print @rwstat to @sf for the device assocaited with @pd.
|
|
*/
|
|
u64 __blkg_prfill_rwstat(struct seq_file *sf, struct blkg_policy_data *pd,
|
|
const struct blkg_rwstat_sample *rwstat)
|
|
{
|
|
static const char *rwstr[] = {
|
|
[BLKG_RWSTAT_READ] = "Read",
|
|
[BLKG_RWSTAT_WRITE] = "Write",
|
|
[BLKG_RWSTAT_SYNC] = "Sync",
|
|
[BLKG_RWSTAT_ASYNC] = "Async",
|
|
[BLKG_RWSTAT_DISCARD] = "Discard",
|
|
};
|
|
const char *dname = blkg_dev_name(pd->blkg);
|
|
u64 v;
|
|
int i;
|
|
|
|
if (!dname)
|
|
return 0;
|
|
|
|
for (i = 0; i < BLKG_RWSTAT_NR; i++)
|
|
seq_printf(sf, "%s %s %llu\n", dname, rwstr[i],
|
|
rwstat->cnt[i]);
|
|
|
|
v = rwstat->cnt[BLKG_RWSTAT_READ] +
|
|
rwstat->cnt[BLKG_RWSTAT_WRITE] +
|
|
rwstat->cnt[BLKG_RWSTAT_DISCARD];
|
|
seq_printf(sf, "%s Total %llu\n", dname, v);
|
|
return v;
|
|
}
|
|
EXPORT_SYMBOL_GPL(__blkg_prfill_rwstat);
|
|
|
|
/**
|
|
* blkg_prfill_rwstat - prfill callback for blkg_rwstat
|
|
* @sf: seq_file to print to
|
|
* @pd: policy private data of interest
|
|
* @off: offset to the blkg_rwstat in @pd
|
|
*
|
|
* prfill callback for printing a blkg_rwstat.
|
|
*/
|
|
u64 blkg_prfill_rwstat(struct seq_file *sf, struct blkg_policy_data *pd,
|
|
int off)
|
|
{
|
|
struct blkg_rwstat_sample rwstat = { };
|
|
|
|
blkg_rwstat_read((void *)pd + off, &rwstat);
|
|
return __blkg_prfill_rwstat(sf, pd, &rwstat);
|
|
}
|
|
EXPORT_SYMBOL_GPL(blkg_prfill_rwstat);
|
|
|
|
/**
|
|
* blkg_rwstat_recursive_sum - collect hierarchical blkg_rwstat
|
|
* @blkg: blkg of interest
|
|
* @pol: blkcg_policy which contains the blkg_rwstat
|
|
* @off: offset to the blkg_rwstat in blkg_policy_data or @blkg
|
|
* @sum: blkg_rwstat_sample structure containing the results
|
|
*
|
|
* Collect the blkg_rwstat specified by @blkg, @pol and @off and all its
|
|
* online descendants and their aux counts. The caller must be holding the
|
|
* queue lock for online tests.
|
|
*
|
|
* If @pol is NULL, blkg_rwstat is at @off bytes into @blkg; otherwise, it
|
|
* is at @off bytes into @blkg's blkg_policy_data of the policy.
|
|
*/
|
|
void blkg_rwstat_recursive_sum(struct blkcg_gq *blkg, struct blkcg_policy *pol,
|
|
int off, struct blkg_rwstat_sample *sum)
|
|
{
|
|
struct blkcg_gq *pos_blkg;
|
|
struct cgroup_subsys_state *pos_css;
|
|
unsigned int i;
|
|
|
|
lockdep_assert_held(&blkg->q->queue_lock);
|
|
|
|
memset(sum, 0, sizeof(*sum));
|
|
rcu_read_lock();
|
|
blkg_for_each_descendant_pre(pos_blkg, pos_css, blkg) {
|
|
struct blkg_rwstat *rwstat;
|
|
|
|
if (!pos_blkg->online)
|
|
continue;
|
|
|
|
if (pol)
|
|
rwstat = (void *)blkg_to_pd(pos_blkg, pol) + off;
|
|
else
|
|
rwstat = (void *)pos_blkg + off;
|
|
|
|
for (i = 0; i < BLKG_RWSTAT_NR; i++)
|
|
sum->cnt[i] += blkg_rwstat_read_counter(rwstat, i);
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
EXPORT_SYMBOL_GPL(blkg_rwstat_recursive_sum);
|