The patch titled
Subject: psi: rename psi fields in preparation for psi trigger addition
has been added to the -mm tree. Its filename is
psi-rename-psi-fields-in-preparation-for-psi-trigger-addition.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/psi-rename-psi-fields-in-preparation-for-psi-trigger-addition.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/psi-rename-psi-fields-in-preparation-for-psi-trigger-addition.patch
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------------------------------------------------------
From: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Subject: psi: rename psi fields in preparation for psi trigger addition
Renaming psi_group structure member fields used for calculating psi totals
and averages for clear distinction between them and trigger-related fields
that will be added next.
Link: http://lkml.kernel.org/r/20190124211518.244221-5-surenb@xxxxxxxxxx
Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Cc: Dennis Zhou <dennis@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Jens Axboe <axboe@xxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Li Zefan <lizefan@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/psi_types.h | 15 ++++++++-------
kernel/sched/psi.c | 26 ++++++++++++++------------
2 files changed, 22 insertions(+), 19 deletions(-)
--- a/include/linux/psi_types.h~psi-rename-psi-fields-in-preparation-for-psi-trigger-addition
+++ a/include/linux/psi_types.h
@@ -69,20 +69,21 @@ struct psi_group_cpu {
};
struct psi_group {
- /* Protects data updated during an aggregation */
- struct mutex stat_lock;
+ /* Protects data used by the aggregator */
+ struct mutex update_lock;
/* Per-cpu task state & time tracking */
struct psi_group_cpu __percpu *pcpu;
- /* Periodic aggregation state */
- u64 total_prev[NR_PSI_STATES - 1];
- u64 last_update;
- u64 next_update;
struct delayed_work clock_work;
- /* Total stall times and sampled pressure averages */
+ /* Total stall times observed */
u64 total[NR_PSI_STATES - 1];
+
+ /* Running pressure averages */
+ u64 avg_total[NR_PSI_STATES - 1];
+ u64 avg_last_update;
+ u64 avg_next_update;
unsigned long avg[NR_PSI_STATES - 1][3];
};
--- a/kernel/sched/psi.c~psi-rename-psi-fields-in-preparation-for-psi-trigger-addition
+++ a/kernel/sched/psi.c
@@ -172,9 +172,9 @@ static void group_init(struct psi_group
for_each_possible_cpu(cpu)
seqcount_init(&per_cpu_ptr(group->pcpu, cpu)->seq);
- group->next_update = sched_clock() + psi_period;
+ group->avg_next_update = sched_clock() + psi_period;
INIT_DELAYED_WORK(&group->clock_work, psi_update_work);
- mutex_init(&group->stat_lock);
+ mutex_init(&group->update_lock);
}
void __init psi_init(void)
@@ -277,7 +277,7 @@ static bool update_stats(struct psi_grou
int cpu;
int s;
- mutex_lock(&group->stat_lock);
+ mutex_lock(&group->update_lock);
/*
* Collect the per-cpu time buckets and average them into a
@@ -318,7 +318,7 @@ static bool update_stats(struct psi_grou
/* avgX= */
now = sched_clock();
- expires = group->next_update;
+ expires = group->avg_next_update;
if (now < expires)
goto out;
if (now - expires > psi_period)
@@ -331,14 +331,14 @@ static bool update_stats(struct psi_grou
* But the deltas we sample out of the per-cpu buckets above
* are based on the actual time elapsing between clock ticks.
*/
- group->next_update = expires + ((1 + missed_periods) * psi_period);
- period = now - (group->last_update + (missed_periods * psi_period));
- group->last_update = now;
+ group->avg_next_update = expires + ((1 + missed_periods) * psi_period);
+ period = now - (group->avg_last_update + (missed_periods * psi_period));
+ group->avg_last_update = now;
for (s = 0; s < NR_PSI_STATES - 1; s++) {
u32 sample;
- sample = group->total[s] - group->total_prev[s];
+ sample = group->total[s] - group->avg_total[s];
/*
* Due to the lockless sampling of the time buckets,
* recorded time deltas can slip into the next period,
@@ -358,11 +358,11 @@ static bool update_stats(struct psi_grou
*/
if (sample > period)
sample = period;
- group->total_prev[s] += sample;
+ group->avg_total[s] += sample;
calc_avgs(group->avg[s], missed_periods, sample, period);
}
out:
- mutex_unlock(&group->stat_lock);
+ mutex_unlock(&group->update_lock);
return nonidle_total;
}
@@ -390,8 +390,10 @@ static void psi_update_work(struct work_
u64 now;
now = sched_clock();
- if (group->next_update > now)
- delay = nsecs_to_jiffies(group->next_update - now) + 1;
+ if (group->avg_next_update > now) {
+ delay = nsecs_to_jiffies(
+ group->avg_next_update - now) + 1;
+ }
schedule_delayed_work(dwork, delay);
}
}
_
Patches currently in -mm which might be from surenb@xxxxxxxxxx are
psi-introduce-state_mask-to-represent-stalled-psi-states.patch
psi-rename-psi-fields-in-preparation-for-psi-trigger-addition.patch
psi-introduce-psi-monitor.patch
