PSI offers 2 mechanisms to get information about a specific resource
pressure. One is reading from /proc/pressure/<resource>, which gives
average pressures aggregated every 2s. The other is creating a pollable
fd for a specific resource and cgroup.
The trigger creation requires CAP_SYS_RESOURCE, and gives the
possibility to pick specific time window and threshold, spawing an RT
thread to aggregate the data.
Systemd would like to provide containers the option to monitor pressure
on their own cgroup and sub-cgroups. For example, if systemd launches a
container that itself then launches services, the container should have
the ability to poll() for pressure in individual services. But neither
the container nor the services are privileged.
The series is implemented in 4 steps in order to reduce the noise of
the change.
V4:
- fixed psi_open leftover usage in IRQ accounting (patch 4/4)
V3:
- restored renaming patch (#2 of 4) as suggested in review
- rebased #3 and #4 on the renaming commit
V2:
- removed renaming patch (previous 2/4) and applied suggested solution
- changed update_triggers side effect removal as suggested in review
- rebased core patch on other V2 changes
Domenico Cerasuolo (4):
sched/psi: rearrange polling code in preparation
sched/psi: rename existing poll members in preparation
sched/psi: extract update_triggers side effect
sched/psi: allow unprivileged polling of N*2s period
Documentation/accounting/psi.rst | 4 +
include/linux/psi.h | 2 +-
include/linux/psi_types.h | 43 +--
kernel/cgroup/cgroup.c | 2 +-
kernel/sched/psi.c | 434 +++++++++++++++++--------------
5 files changed, 263 insertions(+), 222 deletions(-)
--
2.34.1
Renaming in PSI implementation to make a clear distinction between
privileged and unprivileged triggers code to be implemented in the
next patch.
Suggested-by: Johannes Weiner <[email protected]>
Signed-off-by: Domenico Cerasuolo <[email protected]>
---
include/linux/psi_types.h | 36 ++++-----
kernel/sched/psi.c | 163 +++++++++++++++++++-------------------
2 files changed, 100 insertions(+), 99 deletions(-)
diff --git a/include/linux/psi_types.h b/include/linux/psi_types.h
index 1e0a0d7ace3a..1819afa8b198 100644
--- a/include/linux/psi_types.h
+++ b/include/linux/psi_types.h
@@ -175,26 +175,26 @@ struct psi_group {
u64 total[NR_PSI_AGGREGATORS][NR_PSI_STATES - 1];
unsigned long avg[NR_PSI_STATES - 1][3];
- /* Monitor work control */
- struct task_struct __rcu *poll_task;
- struct timer_list poll_timer;
- wait_queue_head_t poll_wait;
- atomic_t poll_wakeup;
- atomic_t poll_scheduled;
+ /* Monitor RT polling work control */
+ struct task_struct __rcu *rtpoll_task;
+ struct timer_list rtpoll_timer;
+ wait_queue_head_t rtpoll_wait;
+ atomic_t rtpoll_wakeup;
+ atomic_t rtpoll_scheduled;
/* Protects data used by the monitor */
- struct mutex trigger_lock;
-
- /* Configured polling triggers */
- struct list_head triggers;
- u32 nr_triggers[NR_PSI_STATES - 1];
- u32 poll_states;
- u64 poll_min_period;
-
- /* Total stall times at the start of monitor activation */
- u64 polling_total[NR_PSI_STATES - 1];
- u64 polling_next_update;
- u64 polling_until;
+ struct mutex rtpoll_trigger_lock;
+
+ /* Configured RT polling triggers */
+ struct list_head rtpoll_triggers;
+ u32 rtpoll_nr_triggers[NR_PSI_STATES - 1];
+ u32 rtpoll_states;
+ u64 rtpoll_min_period;
+
+ /* Total stall times at the start of RT polling monitor activation */
+ u64 rtpoll_total[NR_PSI_STATES - 1];
+ u64 rtpoll_next_update;
+ u64 rtpoll_until;
};
#else /* CONFIG_PSI */
diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c
index fe9269f1d2a4..a3d0b5cf797a 100644
--- a/kernel/sched/psi.c
+++ b/kernel/sched/psi.c
@@ -189,14 +189,14 @@ static void group_init(struct psi_group *group)
INIT_DELAYED_WORK(&group->avgs_work, psi_avgs_work);
mutex_init(&group->avgs_lock);
/* Init trigger-related members */
- atomic_set(&group->poll_scheduled, 0);
- mutex_init(&group->trigger_lock);
- INIT_LIST_HEAD(&group->triggers);
- group->poll_min_period = U32_MAX;
- group->polling_next_update = ULLONG_MAX;
- init_waitqueue_head(&group->poll_wait);
- timer_setup(&group->poll_timer, poll_timer_fn, 0);
- rcu_assign_pointer(group->poll_task, NULL);
+ atomic_set(&group->rtpoll_scheduled, 0);
+ mutex_init(&group->rtpoll_trigger_lock);
+ INIT_LIST_HEAD(&group->rtpoll_triggers);
+ group->rtpoll_min_period = U32_MAX;
+ group->rtpoll_next_update = ULLONG_MAX;
+ init_waitqueue_head(&group->rtpoll_wait);
+ timer_setup(&group->rtpoll_timer, poll_timer_fn, 0);
+ rcu_assign_pointer(group->rtpoll_task, NULL);
}
void __init psi_init(void)
@@ -440,11 +440,11 @@ static u64 update_triggers(struct psi_group *group, u64 now)
* On subsequent updates, calculate growth deltas and let
* watchers know when their specified thresholds are exceeded.
*/
- list_for_each_entry(t, &group->triggers, node) {
+ list_for_each_entry(t, &group->rtpoll_triggers, node) {
u64 growth;
bool new_stall;
- new_stall = group->polling_total[t->state] != total[t->state];
+ new_stall = group->rtpoll_total[t->state] != total[t->state];
/* Check for stall activity or a previous threshold breach */
if (!new_stall && !t->pending_event)
@@ -486,10 +486,10 @@ static u64 update_triggers(struct psi_group *group, u64 now)
}
if (update_total)
- memcpy(group->polling_total, total,
- sizeof(group->polling_total));
+ memcpy(group->rtpoll_total, total,
+ sizeof(group->rtpoll_total));
- return now + group->poll_min_period;
+ return now + group->rtpoll_min_period;
}
static u64 update_averages(struct psi_group *group, u64 now)
@@ -582,53 +582,53 @@ static void init_triggers(struct psi_group *group, u64 now)
{
struct psi_trigger *t;
- list_for_each_entry(t, &group->triggers, node)
+ list_for_each_entry(t, &group->rtpoll_triggers, node)
window_reset(&t->win, now,
group->total[PSI_POLL][t->state], 0);
- memcpy(group->polling_total, group->total[PSI_POLL],
- sizeof(group->polling_total));
- group->polling_next_update = now + group->poll_min_period;
+ memcpy(group->rtpoll_total, group->total[PSI_POLL],
+ sizeof(group->rtpoll_total));
+ group->rtpoll_next_update = now + group->rtpoll_min_period;
}
/* Schedule polling if it's not already scheduled or forced. */
-static void psi_schedule_poll_work(struct psi_group *group, unsigned long delay,
+static void psi_schedule_rtpoll_work(struct psi_group *group, unsigned long delay,
bool force)
{
struct task_struct *task;
/*
* atomic_xchg should be called even when !force to provide a
- * full memory barrier (see the comment inside psi_poll_work).
+ * full memory barrier (see the comment inside psi_rtpoll_work).
*/
- if (atomic_xchg(&group->poll_scheduled, 1) && !force)
+ if (atomic_xchg(&group->rtpoll_scheduled, 1) && !force)
return;
rcu_read_lock();
- task = rcu_dereference(group->poll_task);
+ task = rcu_dereference(group->rtpoll_task);
/*
* kworker might be NULL in case psi_trigger_destroy races with
* psi_task_change (hotpath) which can't use locks
*/
if (likely(task))
- mod_timer(&group->poll_timer, jiffies + delay);
+ mod_timer(&group->rtpoll_timer, jiffies + delay);
else
- atomic_set(&group->poll_scheduled, 0);
+ atomic_set(&group->rtpoll_scheduled, 0);
rcu_read_unlock();
}
-static void psi_poll_work(struct psi_group *group)
+static void psi_rtpoll_work(struct psi_group *group)
{
bool force_reschedule = false;
u32 changed_states;
u64 now;
- mutex_lock(&group->trigger_lock);
+ mutex_lock(&group->rtpoll_trigger_lock);
now = sched_clock();
- if (now > group->polling_until) {
+ if (now > group->rtpoll_until) {
/*
* We are either about to start or might stop polling if no
* state change was recorded. Resetting poll_scheduled leaves
@@ -638,7 +638,7 @@ static void psi_poll_work(struct psi_group *group)
* should be negligible and polling_next_update still keeps
* updates correctly on schedule.
*/
- atomic_set(&group->poll_scheduled, 0);
+ atomic_set(&group->rtpoll_scheduled, 0);
/*
* A task change can race with the poll worker that is supposed to
* report on it. To avoid missing events, ensure ordering between
@@ -667,9 +667,9 @@ static void psi_poll_work(struct psi_group *group)
collect_percpu_times(group, PSI_POLL, &changed_states);
- if (changed_states & group->poll_states) {
+ if (changed_states & group->rtpoll_states) {
/* Initialize trigger windows when entering polling mode */
- if (now > group->polling_until)
+ if (now > group->rtpoll_until)
init_triggers(group, now);
/*
@@ -677,50 +677,50 @@ static void psi_poll_work(struct psi_group *group)
* minimum tracking window as long as monitor states are
* changing.
*/
- group->polling_until = now +
- group->poll_min_period * UPDATES_PER_WINDOW;
+ group->rtpoll_until = now +
+ group->rtpoll_min_period * UPDATES_PER_WINDOW;
}
- if (now > group->polling_until) {
- group->polling_next_update = ULLONG_MAX;
+ if (now > group->rtpoll_until) {
+ group->rtpoll_next_update = ULLONG_MAX;
goto out;
}
- if (now >= group->polling_next_update)
- group->polling_next_update = update_triggers(group, now);
+ if (now >= group->rtpoll_next_update)
+ group->rtpoll_next_update = update_triggers(group, now);
- psi_schedule_poll_work(group,
- nsecs_to_jiffies(group->polling_next_update - now) + 1,
+ psi_schedule_rtpoll_work(group,
+ nsecs_to_jiffies(group->rtpoll_next_update - now) + 1,
force_reschedule);
out:
- mutex_unlock(&group->trigger_lock);
+ mutex_unlock(&group->rtpoll_trigger_lock);
}
-static int psi_poll_worker(void *data)
+static int psi_rtpoll_worker(void *data)
{
struct psi_group *group = (struct psi_group *)data;
sched_set_fifo_low(current);
while (true) {
- wait_event_interruptible(group->poll_wait,
- atomic_cmpxchg(&group->poll_wakeup, 1, 0) ||
+ wait_event_interruptible(group->rtpoll_wait,
+ atomic_cmpxchg(&group->rtpoll_wakeup, 1, 0) ||
kthread_should_stop());
if (kthread_should_stop())
break;
- psi_poll_work(group);
+ psi_rtpoll_work(group);
}
return 0;
}
static void poll_timer_fn(struct timer_list *t)
{
- struct psi_group *group = from_timer(group, t, poll_timer);
+ struct psi_group *group = from_timer(group, t, rtpoll_timer);
- atomic_set(&group->poll_wakeup, 1);
- wake_up_interruptible(&group->poll_wait);
+ atomic_set(&group->rtpoll_wakeup, 1);
+ wake_up_interruptible(&group->rtpoll_wait);
}
static void record_times(struct psi_group_cpu *groupc, u64 now)
@@ -851,8 +851,8 @@ static void psi_group_change(struct psi_group *group, int cpu,
write_seqcount_end(&groupc->seq);
- if (state_mask & group->poll_states)
- psi_schedule_poll_work(group, 1, false);
+ if (state_mask & group->rtpoll_states)
+ psi_schedule_rtpoll_work(group, 1, false);
if (wake_clock && !delayed_work_pending(&group->avgs_work))
schedule_delayed_work(&group->avgs_work, PSI_FREQ);
@@ -1005,8 +1005,8 @@ void psi_account_irqtime(struct task_struct *task, u32 delta)
write_seqcount_end(&groupc->seq);
- if (group->poll_states & (1 << PSI_IRQ_FULL))
- psi_schedule_poll_work(group, 1, false);
+ if (group->rtpoll_states & (1 << PSI_IRQ_FULL))
+ psi_schedule_rtpoll_work(group, 1, false);
} while ((group = group->parent));
}
#endif
@@ -1101,7 +1101,7 @@ void psi_cgroup_free(struct cgroup *cgroup)
cancel_delayed_work_sync(&cgroup->psi->avgs_work);
free_percpu(cgroup->psi->pcpu);
/* All triggers must be removed by now */
- WARN_ONCE(cgroup->psi->poll_states, "psi: trigger leak\n");
+ WARN_ONCE(cgroup->psi->rtpoll_states, "psi: trigger leak\n");
kfree(cgroup->psi);
}
@@ -1302,29 +1302,29 @@ struct psi_trigger *psi_trigger_create(struct psi_group *group,
init_waitqueue_head(&t->event_wait);
t->pending_event = false;
- mutex_lock(&group->trigger_lock);
+ mutex_lock(&group->rtpoll_trigger_lock);
- if (!rcu_access_pointer(group->poll_task)) {
+ if (!rcu_access_pointer(group->rtpoll_task)) {
struct task_struct *task;
- task = kthread_create(psi_poll_worker, group, "psimon");
+ task = kthread_create(psi_rtpoll_worker, group, "psimon");
if (IS_ERR(task)) {
kfree(t);
- mutex_unlock(&group->trigger_lock);
+ mutex_unlock(&group->rtpoll_trigger_lock);
return ERR_CAST(task);
}
- atomic_set(&group->poll_wakeup, 0);
+ atomic_set(&group->rtpoll_wakeup, 0);
wake_up_process(task);
- rcu_assign_pointer(group->poll_task, task);
+ rcu_assign_pointer(group->rtpoll_task, task);
}
- list_add(&t->node, &group->triggers);
- group->poll_min_period = min(group->poll_min_period,
+ list_add(&t->node, &group->rtpoll_triggers);
+ group->rtpoll_min_period = min(group->rtpoll_min_period,
div_u64(t->win.size, UPDATES_PER_WINDOW));
- group->nr_triggers[t->state]++;
- group->poll_states |= (1 << t->state);
+ group->rtpoll_nr_triggers[t->state]++;
+ group->rtpoll_states |= (1 << t->state);
- mutex_unlock(&group->trigger_lock);
+ mutex_unlock(&group->rtpoll_trigger_lock);
return t;
}
@@ -1349,51 +1349,52 @@ void psi_trigger_destroy(struct psi_trigger *t)
*/
wake_up_pollfree(&t->event_wait);
- mutex_lock(&group->trigger_lock);
+ mutex_lock(&group->rtpoll_trigger_lock);
if (!list_empty(&t->node)) {
struct psi_trigger *tmp;
u64 period = ULLONG_MAX;
list_del(&t->node);
- group->nr_triggers[t->state]--;
- if (!group->nr_triggers[t->state])
- group->poll_states &= ~(1 << t->state);
+ group->rtpoll_nr_triggers[t->state]--;
+ if (!group->rtpoll_nr_triggers[t->state])
+ group->rtpoll_states &= ~(1 << t->state);
/* reset min update period for the remaining triggers */
- list_for_each_entry(tmp, &group->triggers, node)
+ list_for_each_entry(tmp, &group->rtpoll_triggers, node)
period = min(period, div_u64(tmp->win.size,
UPDATES_PER_WINDOW));
- group->poll_min_period = period;
- /* Destroy poll_task when the last trigger is destroyed */
- if (group->poll_states == 0) {
- group->polling_until = 0;
+ group->rtpoll_min_period = period;
+ /* Destroy rtpoll_task when the last trigger is destroyed */
+ if (group->rtpoll_states == 0) {
+ group->rtpoll_until = 0;
task_to_destroy = rcu_dereference_protected(
- group->poll_task,
- lockdep_is_held(&group->trigger_lock));
- rcu_assign_pointer(group->poll_task, NULL);
- del_timer(&group->poll_timer);
+ group->rtpoll_task,
+ lockdep_is_held(&group->rtpoll_trigger_lock));
+ rcu_assign_pointer(group->rtpoll_task, NULL);
+ del_timer(&group->rtpoll_timer);
}
}
- mutex_unlock(&group->trigger_lock);
+ mutex_unlock(&group->rtpoll_trigger_lock);
/*
- * Wait for psi_schedule_poll_work RCU to complete its read-side
+ * Wait for psi_schedule_rtpoll_work RCU to complete its read-side
* critical section before destroying the trigger and optionally the
- * poll_task.
+ * rtpoll_task.
*/
synchronize_rcu();
/*
- * Stop kthread 'psimon' after releasing trigger_lock to prevent a
- * deadlock while waiting for psi_poll_work to acquire trigger_lock
+ * Stop kthread 'psimon' after releasing rtpoll_trigger_lock to prevent
+ * a deadlock while waiting for psi_rtpoll_work to acquire
+ * rtpoll_trigger_lock
*/
if (task_to_destroy) {
/*
* After the RCU grace period has expired, the worker
- * can no longer be found through group->poll_task.
+ * can no longer be found through group->rtpoll_task.
*/
kthread_stop(task_to_destroy);
- atomic_set(&group->poll_scheduled, 0);
+ atomic_set(&group->rtpoll_scheduled, 0);
}
kfree(t);
}
--
2.34.1
Move a few functions up in the file to avoid forward declaration needed
in the patch implementing unprivileged PSI triggers.
Suggested-by: Johannes Weiner <[email protected]>
Signed-off-by: Domenico Cerasuolo <[email protected]>
---
kernel/sched/psi.c | 196 ++++++++++++++++++++++-----------------------
1 file changed, 98 insertions(+), 98 deletions(-)
diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c
index 02e011cabe91..fe9269f1d2a4 100644
--- a/kernel/sched/psi.c
+++ b/kernel/sched/psi.c
@@ -384,92 +384,6 @@ static void collect_percpu_times(struct psi_group *group,
*pchanged_states = changed_states;
}
-static u64 update_averages(struct psi_group *group, u64 now)
-{
- unsigned long missed_periods = 0;
- u64 expires, period;
- u64 avg_next_update;
- int s;
-
- /* avgX= */
- expires = group->avg_next_update;
- if (now - expires >= psi_period)
- missed_periods = div_u64(now - expires, psi_period);
-
- /*
- * The periodic clock tick can get delayed for various
- * reasons, especially on loaded systems. To avoid clock
- * drift, we schedule the clock in fixed psi_period intervals.
- * But the deltas we sample out of the per-cpu buckets above
- * are based on the actual time elapsing between clock ticks.
- */
- 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[PSI_AVGS][s] - group->avg_total[s];
- /*
- * Due to the lockless sampling of the time buckets,
- * recorded time deltas can slip into the next period,
- * which under full pressure can result in samples in
- * excess of the period length.
- *
- * We don't want to report non-sensical pressures in
- * excess of 100%, nor do we want to drop such events
- * on the floor. Instead we punt any overage into the
- * future until pressure subsides. By doing this we
- * don't underreport the occurring pressure curve, we
- * just report it delayed by one period length.
- *
- * The error isn't cumulative. As soon as another
- * delta slips from a period P to P+1, by definition
- * it frees up its time T in P.
- */
- if (sample > period)
- sample = period;
- group->avg_total[s] += sample;
- calc_avgs(group->avg[s], missed_periods, sample, period);
- }
-
- return avg_next_update;
-}
-
-static void psi_avgs_work(struct work_struct *work)
-{
- struct delayed_work *dwork;
- struct psi_group *group;
- u32 changed_states;
- u64 now;
-
- dwork = to_delayed_work(work);
- group = container_of(dwork, struct psi_group, avgs_work);
-
- mutex_lock(&group->avgs_lock);
-
- now = sched_clock();
-
- collect_percpu_times(group, PSI_AVGS, &changed_states);
- /*
- * If there is task activity, periodically fold the per-cpu
- * times and feed samples into the running averages. If things
- * are idle and there is no data to process, stop the clock.
- * Once restarted, we'll catch up the running averages in one
- * go - see calc_avgs() and missed_periods.
- */
- if (now >= group->avg_next_update)
- group->avg_next_update = update_averages(group, now);
-
- if (changed_states & PSI_STATE_RESCHEDULE) {
- schedule_delayed_work(dwork, nsecs_to_jiffies(
- group->avg_next_update - now) + 1);
- }
-
- mutex_unlock(&group->avgs_lock);
-}
-
/* Trigger tracking window manipulations */
static void window_reset(struct psi_window *win, u64 now, u64 value,
u64 prev_growth)
@@ -516,18 +430,6 @@ static u64 window_update(struct psi_window *win, u64 now, u64 value)
return growth;
}
-static void init_triggers(struct psi_group *group, u64 now)
-{
- struct psi_trigger *t;
-
- list_for_each_entry(t, &group->triggers, node)
- window_reset(&t->win, now,
- group->total[PSI_POLL][t->state], 0);
- memcpy(group->polling_total, group->total[PSI_POLL],
- sizeof(group->polling_total));
- group->polling_next_update = now + group->poll_min_period;
-}
-
static u64 update_triggers(struct psi_group *group, u64 now)
{
struct psi_trigger *t;
@@ -590,6 +492,104 @@ static u64 update_triggers(struct psi_group *group, u64 now)
return now + group->poll_min_period;
}
+static u64 update_averages(struct psi_group *group, u64 now)
+{
+ unsigned long missed_periods = 0;
+ u64 expires, period;
+ u64 avg_next_update;
+ int s;
+
+ /* avgX= */
+ expires = group->avg_next_update;
+ if (now - expires >= psi_period)
+ missed_periods = div_u64(now - expires, psi_period);
+
+ /*
+ * The periodic clock tick can get delayed for various
+ * reasons, especially on loaded systems. To avoid clock
+ * drift, we schedule the clock in fixed psi_period intervals.
+ * But the deltas we sample out of the per-cpu buckets above
+ * are based on the actual time elapsing between clock ticks.
+ */
+ 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[PSI_AVGS][s] - group->avg_total[s];
+ /*
+ * Due to the lockless sampling of the time buckets,
+ * recorded time deltas can slip into the next period,
+ * which under full pressure can result in samples in
+ * excess of the period length.
+ *
+ * We don't want to report non-sensical pressures in
+ * excess of 100%, nor do we want to drop such events
+ * on the floor. Instead we punt any overage into the
+ * future until pressure subsides. By doing this we
+ * don't underreport the occurring pressure curve, we
+ * just report it delayed by one period length.
+ *
+ * The error isn't cumulative. As soon as another
+ * delta slips from a period P to P+1, by definition
+ * it frees up its time T in P.
+ */
+ if (sample > period)
+ sample = period;
+ group->avg_total[s] += sample;
+ calc_avgs(group->avg[s], missed_periods, sample, period);
+ }
+
+ return avg_next_update;
+}
+
+static void psi_avgs_work(struct work_struct *work)
+{
+ struct delayed_work *dwork;
+ struct psi_group *group;
+ u32 changed_states;
+ u64 now;
+
+ dwork = to_delayed_work(work);
+ group = container_of(dwork, struct psi_group, avgs_work);
+
+ mutex_lock(&group->avgs_lock);
+
+ now = sched_clock();
+
+ collect_percpu_times(group, PSI_AVGS, &changed_states);
+ /*
+ * If there is task activity, periodically fold the per-cpu
+ * times and feed samples into the running averages. If things
+ * are idle and there is no data to process, stop the clock.
+ * Once restarted, we'll catch up the running averages in one
+ * go - see calc_avgs() and missed_periods.
+ */
+ if (now >= group->avg_next_update)
+ group->avg_next_update = update_averages(group, now);
+
+ if (changed_states & PSI_STATE_RESCHEDULE) {
+ schedule_delayed_work(dwork, nsecs_to_jiffies(
+ group->avg_next_update - now) + 1);
+ }
+
+ mutex_unlock(&group->avgs_lock);
+}
+
+static void init_triggers(struct psi_group *group, u64 now)
+{
+ struct psi_trigger *t;
+
+ list_for_each_entry(t, &group->triggers, node)
+ window_reset(&t->win, now,
+ group->total[PSI_POLL][t->state], 0);
+ memcpy(group->polling_total, group->total[PSI_POLL],
+ sizeof(group->polling_total));
+ group->polling_next_update = now + group->poll_min_period;
+}
+
/* Schedule polling if it's not already scheduled or forced. */
static void psi_schedule_poll_work(struct psi_group *group, unsigned long delay,
bool force)
--
2.34.1
On Wed, Mar 29, 2023 at 05:33:24PM +0200, Domenico Cerasuolo wrote:
> Move a few functions up in the file to avoid forward declaration needed
> in the patch implementing unprivileged PSI triggers.
>
> Suggested-by: Johannes Weiner <[email protected]>
> Signed-off-by: Domenico Cerasuolo <[email protected]>
Acked-by: Johannes Weiner <[email protected]>
On Wed, Mar 29, 2023 at 05:33:25PM +0200, Domenico Cerasuolo wrote:
> Renaming in PSI implementation to make a clear distinction between
> privileged and unprivileged triggers code to be implemented in the
> next patch.
>
> Suggested-by: Johannes Weiner <[email protected]>
> Signed-off-by: Domenico Cerasuolo <[email protected]>
Acked-by: Johannes Weiner <[email protected]>