PM: sleep: Pause cpuidle later and resume it earlier during system transitions

Commit 8651f97bd951 ("PM / cpuidle: System resume hang fix with cpuidle") that introduced cpuidle pausing during system suspend did that to work around a platform firmware issue causing systems to hang during resume if CPUs were allowed to enter idle states in the system suspend and resume code paths. However, pausing cpuidle before the last phase of suspending devices is the source of an otherwise arbitrary difference between the suspend-to-idle path and other system suspend variants, so it is cleaner to do that later, before taking secondary CPUs offline (it is still safer to take secondary CPUs offline with cpuidle paused, though). Modify the code accordingly, but in order to avoid code duplication, introduce new wrapper functions, pm_sleep_disable_secondary_cpus() and pm_sleep_enable_secondary_cpus(), to combine cpuidle_pause() and cpuidle_resume(), respectively, with the handling of secondary CPUs during system-wide transitions to sleep states.

Rafael J. Wysocki committed 5 years ago

Commit 23f62d71 parent 8d898354 files · +24 −20Browse files

Showing the changes to kernel (3 of 4 files). Show all

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3 files

kernel/power/hibernate.c +7 −5
kernel/power/power.h +14 −0
kernel/power/suspend.c +2 −8

kernel/power/hibernate.c+7−5

@@ -300,7 +300,7 @@ static int create_image(int platform_mode) · 299 unmodified lines
300	300	if (error \|\| hibernation_test(TEST_PLATFORM))
301	301	goto Platform_finish;
302	302
303		− error = suspend_disable_secondary_cpus();
	303	+ error = pm_sleep_disable_secondary_cpus();
304	304	if (error \|\| hibernation_test(TEST_CPUS))
305	305	goto Enable_cpus;
306	306
@@ -342,7 +342,7 @@ static int create_image(int platform_mode) · 35 unmodified lines
342	342	local_irq_enable();
343	343
344	344	Enable_cpus:
345		− suspend_enable_secondary_cpus();
	345	+ pm_sleep_enable_secondary_cpus();
346	346
347	347	/* Allow architectures to do nosmt-specific post-resume dances */
348	348	if (!in_suspend)
@@ -466,6 +466,8 @@ static int resume_target_kernel(bool platform_mode) · 117 unmodified lines
466	466	if (error)
467	467	goto Cleanup;
468	468
	469	+ cpuidle_pause();
	470	+
469	471	error = hibernate_resume_nonboot_cpu_disable();
470	472	if (error)
471	473	goto Enable_cpus;
@@ -509,7 +511,7 @@ static int resume_target_kernel(bool platform_mode) · 37 unmodified lines
509	511	local_irq_enable();
510	512
511	513	Enable_cpus:
512		− suspend_enable_secondary_cpus();
	514	+ pm_sleep_enable_secondary_cpus();
513	515
514	516	Cleanup:
515	517	platform_restore_cleanup(platform_mode);
@@ -587,7 +589,7 @@ int hibernation_platform_enter(void) · 71 unmodified lines
587	589	if (error)
588	590	goto Platform_finish;
589	591
590		− error = suspend_disable_secondary_cpus();
	592	+ error = pm_sleep_disable_secondary_cpus();
591	593	if (error)
592	594	goto Enable_cpus;
593	595
@@ -609,7 +611,7 @@ int hibernation_platform_enter(void) · 15 unmodified lines
609	611	local_irq_enable();
610	612
611	613	Enable_cpus:
612		− suspend_enable_secondary_cpus();
	614	+ pm_sleep_enable_secondary_cpus();
613	615
614	616	Platform_finish:
615	617	hibernation_ops->finish();

kernel/power/power.h+14−0

@@ -4,6 +4,8 @@ · 3 unmodified lines
4	4	#include <linux/utsname.h>
5	5	#include <linux/freezer.h>
6	6	#include <linux/compiler.h>
	7	+#include <linux/cpu.h>
	8	+#include <linux/cpuidle.h>
7	9
8	10	struct swsusp_info {
9	11	struct new_utsname uts;
@@ -310,3 +312,15 @@ extern int pm_wake_lock(const char *buf); · 300 unmodified lines
310	312	extern int pm_wake_unlock(const char *buf);
311	313
312	314	#endif /* !CONFIG_PM_WAKELOCKS */
	315	+
	316	+static inline int pm_sleep_disable_secondary_cpus(void)
	317	+{
	318	+ cpuidle_pause();
	319	+ return suspend_disable_secondary_cpus();
	320	+}
	321	+
	322	+static inline void pm_sleep_enable_secondary_cpus(void)
	323	+{
	324	+ suspend_enable_secondary_cpus();
	325	+ cpuidle_resume();
	326	+}

kernel/power/suspend.c+2−8

@@ -403,9 +403,6 @@ static int suspend_enter(suspend_state_t state, bool *wakeup) · 402 unmodified lines
403	403	if (error)
404	404	goto Devices_early_resume;
405	405
406		− if (state != PM_SUSPEND_TO_IDLE)
407		− cpuidle_pause();
408		−
409	406	error = dpm_suspend_noirq(PMSG_SUSPEND);
410	407	if (error) {
411	408	pr_err("noirq suspend of devices failed\n");
@@ -423,7 +420,7 @@ static int suspend_enter(suspend_state_t state, bool *wakeup) · 11 unmodified lines
423	420	goto Platform_wake;
424	421	}
425	422
426		− error = suspend_disable_secondary_cpus();
	423	+ error = pm_sleep_disable_secondary_cpus();
427	424	if (error \|\| suspend_test(TEST_CPUS))
428	425	goto Enable_cpus;
429	426
@@ -453,16 +450,13 @@ static int suspend_enter(suspend_state_t state, bool *wakeup) · 23 unmodified lines
453	450	BUG_ON(irqs_disabled());
454	451
455	452	Enable_cpus:
456		− suspend_enable_secondary_cpus();
	453	+ pm_sleep_enable_secondary_cpus();
457	454
458	455	Platform_wake:
459	456	platform_resume_noirq(state);
460	457	dpm_resume_noirq(PMSG_RESUME);
461	458
462	459	Platform_early_resume:
463		− if (state != PM_SUSPEND_TO_IDLE)
464		− cpuidle_resume();
465		−
466	460	platform_resume_early(state);
467	461
468	462	Devices_early_resume: