blkcg: make blkg_[rw]stat_recursive_sum() to be able to index into blkcg_gq

Currently, blkg_[rw]stat_recursive_sum() assume that the target
counter is located in pd (blkg_policy_data); however, some counters
are planned to be moved to blkg (blkcg_gq).

This patch updates blkg_[rw]stat_recursive_sum() to take blkg and
blkg_policy pointers instead of pd.  If policy is NULL, it indexes
into blkg.  If non-NULL, into the blkg's pd of the policy.

The existing usages are updated to maintain the current behaviors.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Tejun Heo 2015-08-18 14:55:23 -07:00 committed by Jens Axboe
parent 24bdb8ef06
commit f12c74cab1
3 changed files with 50 additions and 34 deletions

View File

@ -581,30 +581,39 @@ EXPORT_SYMBOL_GPL(blkg_prfill_rwstat);
/**
* blkg_stat_recursive_sum - collect hierarchical blkg_stat
* @pd: policy private data of interest
* @off: offset to the blkg_stat in @pd
* @blkg: blkg of interest
* @pol: blkcg_policy which contains the blkg_stat
* @off: offset to the blkg_stat in blkg_policy_data or @blkg
*
* Collect the blkg_stat specified by @off from @pd and all its online
* descendants and their aux counts. The caller must be holding the queue
* lock for online tests.
* Collect the blkg_stat 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_stat is at @off bytes into @blkg; otherwise, it is
* at @off bytes into @blkg's blkg_policy_data of the policy.
*/
u64 blkg_stat_recursive_sum(struct blkg_policy_data *pd, int off)
u64 blkg_stat_recursive_sum(struct blkcg_gq *blkg,
struct blkcg_policy *pol, int off)
{
struct blkcg_policy *pol = blkcg_policy[pd->plid];
struct blkcg_gq *pos_blkg;
struct cgroup_subsys_state *pos_css;
u64 sum = 0;
lockdep_assert_held(pd->blkg->q->queue_lock);
lockdep_assert_held(blkg->q->queue_lock);
rcu_read_lock();
blkg_for_each_descendant_pre(pos_blkg, pos_css, pd_to_blkg(pd)) {
struct blkg_policy_data *pos_pd = blkg_to_pd(pos_blkg, pol);
struct blkg_stat *stat = (void *)pos_pd + off;
blkg_for_each_descendant_pre(pos_blkg, pos_css, blkg) {
struct blkg_stat *stat;
if (pos_blkg->online)
sum += blkg_stat_read(stat) +
atomic64_read(&stat->aux_cnt);
if (!pos_blkg->online)
continue;
if (pol)
stat = (void *)blkg_to_pd(pos_blkg, pol) + off;
else
stat = (void *)blkg + off;
sum += blkg_stat_read(stat) + atomic64_read(&stat->aux_cnt);
}
rcu_read_unlock();
@ -614,33 +623,39 @@ EXPORT_SYMBOL_GPL(blkg_stat_recursive_sum);
/**
* blkg_rwstat_recursive_sum - collect hierarchical blkg_rwstat
* @pd: policy private data of interest
* @off: offset to the blkg_stat in @pd
* @blkg: blkg of interest
* @pol: blkcg_policy which contains the blkg_rwstat
* @off: offset to the blkg_rwstat in blkg_policy_data or @blkg
*
* Collect the blkg_rwstat specified by @off from @pd and all its online
* descendants and their aux counts. The caller must be holding the queue
* lock for online tests.
* 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.
*/
struct blkg_rwstat blkg_rwstat_recursive_sum(struct blkg_policy_data *pd,
int off)
struct blkg_rwstat blkg_rwstat_recursive_sum(struct blkcg_gq *blkg,
struct blkcg_policy *pol, int off)
{
struct blkcg_policy *pol = blkcg_policy[pd->plid];
struct blkcg_gq *pos_blkg;
struct cgroup_subsys_state *pos_css;
struct blkg_rwstat sum = { };
int i;
lockdep_assert_held(pd->blkg->q->queue_lock);
lockdep_assert_held(blkg->q->queue_lock);
rcu_read_lock();
blkg_for_each_descendant_pre(pos_blkg, pos_css, pd_to_blkg(pd)) {
struct blkg_policy_data *pos_pd = blkg_to_pd(pos_blkg, pol);
struct blkg_rwstat *rwstat = (void *)pos_pd + off;
struct blkg_rwstat tmp;
blkg_for_each_descendant_pre(pos_blkg, pos_css, blkg) {
struct blkg_rwstat *rwstat, tmp;
if (!pos_blkg->online)
continue;
if (pol)
rwstat = (void *)blkg_to_pd(pos_blkg, pol) + off;
else
rwstat = (void *)pos_blkg + off;
tmp = blkg_rwstat_read(rwstat);
for (i = 0; i < BLKG_RWSTAT_NR; i++)

View File

@ -1886,16 +1886,16 @@ static int cfqg_print_rwstat(struct seq_file *sf, void *v)
static u64 cfqg_prfill_stat_recursive(struct seq_file *sf,
struct blkg_policy_data *pd, int off)
{
u64 sum = blkg_stat_recursive_sum(pd, off);
u64 sum = blkg_stat_recursive_sum(pd_to_blkg(pd),
&blkcg_policy_cfq, off);
return __blkg_prfill_u64(sf, pd, sum);
}
static u64 cfqg_prfill_rwstat_recursive(struct seq_file *sf,
struct blkg_policy_data *pd, int off)
{
struct blkg_rwstat sum = blkg_rwstat_recursive_sum(pd, off);
struct blkg_rwstat sum = blkg_rwstat_recursive_sum(pd_to_blkg(pd),
&blkcg_policy_cfq, off);
return __blkg_prfill_rwstat(sf, pd, &sum);
}

View File

@ -191,9 +191,10 @@ u64 blkg_prfill_stat(struct seq_file *sf, struct blkg_policy_data *pd, int off);
u64 blkg_prfill_rwstat(struct seq_file *sf, struct blkg_policy_data *pd,
int off);
u64 blkg_stat_recursive_sum(struct blkg_policy_data *pd, int off);
struct blkg_rwstat blkg_rwstat_recursive_sum(struct blkg_policy_data *pd,
int off);
u64 blkg_stat_recursive_sum(struct blkcg_gq *blkg,
struct blkcg_policy *pol, int off);
struct blkg_rwstat blkg_rwstat_recursive_sum(struct blkcg_gq *blkg,
struct blkcg_policy *pol, int off);
struct blkg_conf_ctx {
struct gendisk *disk;