diff mbox series

[RFC,9/9] cpuidle: Use local_clock_noinstr()

Message ID	20230508213147.990013706@infradead.org
State	New
Headers	Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Message-ID: <20230508213147.990013706@infradead.org> User-Agent: quilt/0.66 Date: Mon, 08 May 2023 23:20:00 +0200 From: Peter Zijlstra <peterz@infradead.org> To: bigeasy@linutronix.de Cc: mark.rutland@arm.com, maz@kernel.org, catalin.marinas@arm.com, will@kernel.org, chenhuacai@kernel.org, kernel@xen0n.name, hca@linux.ibm.com, gor@linux.ibm.com, agordeev@linux.ibm.com, borntraeger@linux.ibm.com, svens@linux.ibm.com, pbonzini@redhat.com, wanpengli@tencent.com, vkuznets@redhat.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, jgross@suse.com, boris.ostrovsky@oracle.com, daniel.lezcano@linaro.org, kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, rafael@kernel.org, peterz@infradead.org, longman@redhat.com, boqun.feng@gmail.com, pmladek@suse.com, senozhatsky@chromium.org, rostedt@goodmis.org, john.ogness@linutronix.de, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com, jstultz@google.com, sboyd@kernel.org, linux-kernel@vger.kernel.org, loongarch@lists.linux.dev, linux-s390@vger.kernel.org, kvm@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-pm@vger.kernel.org Subject: [RFC][PATCH 9/9] cpuidle: Use local_clock_noinstr() References: <20230508211951.901961964@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Precedence: bulk
Series	local_clock() vs noinstr \| [RFC,0/9] local_clock() vs noinstr [RFC,1/9] seqlock/latch: Provide raw_read_seqcount_latch_retry() [RFC,2/9] time/sched_clock: Provide sched_clock_noinstr() [RFC,3/9] arm64/io: Always inline all of __raw_{read,write}[bwlq]() [RFC,4/9] arm64/arch_timer: Provide noinstr sched_clock_read() functions [RFC,5/9] loongarch: Provide noinstr sched_clock_read() [RFC,6/9] s390/time: Provide sched_clock_noinstr() [RFC,7/9] x86/tsc: Provide sched_clock_noinstr() [RFC,8/9] sched/clock: Provide local_clock_noinstr() [RFC,9/9] cpuidle: Use local_clock_noinstr()

Commit Message

Peter Zijlstra May 8, 2023, 9:20 p.m. UTC

  With the introduction of local_clock_noinstr(), local_clock() itself
is no longer marked noinstr, use the correct function.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
 drivers/cpuidle/cpuidle.c    |    8 ++++----
 drivers/cpuidle/poll_state.c |    4 ++--
 2 files changed, 6 insertions(+), 6 deletions(-)

Comments

Rafael J. Wysocki May 9, 2023, 4:18 p.m. UTC | #1

On Mon, May 8, 2023 at 11:34 PM Peter Zijlstra <peterz@infradead.org> wrote:
>
> With the introduction of local_clock_noinstr(), local_clock() itself
> is no longer marked noinstr, use the correct function.
>
> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> ---
>  drivers/cpuidle/cpuidle.c    |    8 ++++----
>  drivers/cpuidle/poll_state.c |    4 ++--
>  2 files changed, 6 insertions(+), 6 deletions(-)
>
> --- a/drivers/cpuidle/cpuidle.c
> +++ b/drivers/cpuidle/cpuidle.c
> @@ -145,7 +145,7 @@ static noinstr void enter_s2idle_proper(
>
>         instrumentation_begin();
>
> -       time_start = ns_to_ktime(local_clock());
> +       time_start = ns_to_ktime(local_clock_noinstr());
>
>         tick_freeze();
>         /*
> @@ -169,7 +169,7 @@ static noinstr void enter_s2idle_proper(
>         tick_unfreeze();
>         start_critical_timings();
>
> -       time_end = ns_to_ktime(local_clock());
> +       time_end = ns_to_ktime(local_clock_noinstr());
>
>         dev->states_usage[index].s2idle_time += ktime_us_delta(time_end, time_start);
>         dev->states_usage[index].s2idle_usage++;
> @@ -243,7 +243,7 @@ noinstr int cpuidle_enter_state(struct c
>         sched_idle_set_state(target_state);
>
>         trace_cpu_idle(index, dev->cpu);
> -       time_start = ns_to_ktime(local_clock());
> +       time_start = ns_to_ktime(local_clock_noinstr());
>
>         stop_critical_timings();
>         if (!(target_state->flags & CPUIDLE_FLAG_RCU_IDLE)) {
> @@ -276,7 +276,7 @@ noinstr int cpuidle_enter_state(struct c
>         start_critical_timings();
>
>         sched_clock_idle_wakeup_event();
> -       time_end = ns_to_ktime(local_clock());
> +       time_end = ns_to_ktime(local_clock_noinstr());
>         trace_cpu_idle(PWR_EVENT_EXIT, dev->cpu);
>
>         /* The cpu is no longer idle or about to enter idle. */
> --- a/drivers/cpuidle/poll_state.c
> +++ b/drivers/cpuidle/poll_state.c
> @@ -15,7 +15,7 @@ static int __cpuidle poll_idle(struct cp
>  {
>         u64 time_start;
>
> -       time_start = local_clock();
> +       time_start = local_clock_noinstr();
>
>         dev->poll_time_limit = false;
>
> @@ -32,7 +32,7 @@ static int __cpuidle poll_idle(struct cp
>                                 continue;
>
>                         loop_count = 0;
> -                       if (local_clock() - time_start > limit) {
> +                       if (local_clock_noinstr() - time_start > limit) {
>                                 dev->poll_time_limit = true;
>                                 break;
>                         }
>

The above LGTM, but the teo governors uses local_clock() too.  Should
it use the _noinstr() version?

Peter Zijlstra May 9, 2023, 7:02 p.m. UTC | #2

On Tue, May 09, 2023 at 06:18:08PM +0200, Rafael J. Wysocki wrote:
> On Mon, May 8, 2023 at 11:34 PM Peter Zijlstra <peterz@infradead.org> wrote:
> > --- a/drivers/cpuidle/poll_state.c
> > +++ b/drivers/cpuidle/poll_state.c
> > @@ -15,7 +15,7 @@ static int __cpuidle poll_idle(struct cp
> >  {
> >         u64 time_start;
> >
> > -       time_start = local_clock();
> > +       time_start = local_clock_noinstr();
> >
> >         dev->poll_time_limit = false;
> >
> > @@ -32,7 +32,7 @@ static int __cpuidle poll_idle(struct cp
> >                                 continue;
> >
> >                         loop_count = 0;
> > -                       if (local_clock() - time_start > limit) {
> > +                       if (local_clock_noinstr() - time_start > limit) {
> >                                 dev->poll_time_limit = true;
> >                                 break;
> >                         }
> >
> 
> The above LGTM, but the teo governors uses local_clock() too.  Should
> it use the _noinstr() version?

Only the callsites from noinstr or __cpuidle functions, IIRC the
governors are neither and should be OK.

diff mbox series

Patch

--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -145,7 +145,7 @@  static noinstr void enter_s2idle_proper(
 
 	instrumentation_begin();
 
-	time_start = ns_to_ktime(local_clock());
+	time_start = ns_to_ktime(local_clock_noinstr());
 
 	tick_freeze();
 	/*
@@ -169,7 +169,7 @@  static noinstr void enter_s2idle_proper(
 	tick_unfreeze();
 	start_critical_timings();
 
-	time_end = ns_to_ktime(local_clock());
+	time_end = ns_to_ktime(local_clock_noinstr());
 
 	dev->states_usage[index].s2idle_time += ktime_us_delta(time_end, time_start);
 	dev->states_usage[index].s2idle_usage++;
@@ -243,7 +243,7 @@  noinstr int cpuidle_enter_state(struct c
 	sched_idle_set_state(target_state);
 
 	trace_cpu_idle(index, dev->cpu);
-	time_start = ns_to_ktime(local_clock());
+	time_start = ns_to_ktime(local_clock_noinstr());
 
 	stop_critical_timings();
 	if (!(target_state->flags & CPUIDLE_FLAG_RCU_IDLE)) {
@@ -276,7 +276,7 @@  noinstr int cpuidle_enter_state(struct c
 	start_critical_timings();
 
 	sched_clock_idle_wakeup_event();
-	time_end = ns_to_ktime(local_clock());
+	time_end = ns_to_ktime(local_clock_noinstr());
 	trace_cpu_idle(PWR_EVENT_EXIT, dev->cpu);
 
 	/* The cpu is no longer idle or about to enter idle. */
--- a/drivers/cpuidle/poll_state.c
+++ b/drivers/cpuidle/poll_state.c
@@ -15,7 +15,7 @@  static int __cpuidle poll_idle(struct cp
 {
 	u64 time_start;
 
-	time_start = local_clock();
+	time_start = local_clock_noinstr();
 
 	dev->poll_time_limit = false;
 
@@ -32,7 +32,7 @@  static int __cpuidle poll_idle(struct cp
 				continue;
 
 			loop_count = 0;
-			if (local_clock() - time_start > limit) {
+			if (local_clock_noinstr() - time_start > limit) {
 				dev->poll_time_limit = true;
 				break;
 			}