Commit f688b599 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'pm-6.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm 

Pull power management fixes from Rafael Wysocki:
 "These fix the cpupower utility installation, fix up the recently added
  Rust abstractions for cpufreq and OPP, restore the x86 update
  eliminating mwait_play_dead_cpuid_hint() that has been reverted during
  the 6.16 merge window along with preventing the failure caused by it
  from happening, and clean up mwait_idle_with_hints() usage in
  intel_idle:

   - Implement CpuId Rust abstraction and use it to fix doctest failure
     related to the recently introduced cpumask abstraction (Viresh
     Kumar)

   - Do minor cleanups in the `# Safety` sections for cpufreq
     abstractions added recently (Viresh Kumar)

   - Unbreak cpupower systemd service units installation on some systems
     by adding a unitdir variable for specifying the location to install
     them (Francesco Poli)

   - Eliminate mwait_play_dead_cpuid_hint() again after reverting its
     elimination during the 6.16 merge window due to a problem with
     handling "dead" SMT siblings, but this time prevent leaving them in
     C1 after initialization by taking them online and back offline when
     a proper cpuidle driver for the platform has been registered
     (Rafael Wysocki)

   - Update data types of variables passed as arguments to
     mwait_idle_with_hints() to match the function definition after
     recent changes (Uros Bizjak)"

* tag 'pm-6.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  rust: cpu: Add CpuId::current() to retrieve current CPU ID
  rust: Use CpuId in place of raw CPU numbers
  rust: cpu: Introduce CpuId abstraction
  intel_idle: Update arguments of mwait_idle_with_hints()
  cpufreq: Convert `/// SAFETY` lines to `# Safety` sections
  cpupower: split unitdir from libdir in Makefile
  Reapply "x86/smp: Eliminate mwait_play_dead_cpuid_hint()"
  ACPI: processor: Rescan "dead" SMT siblings during initialization
  intel_idle: Rescan "dead" SMT siblings during initialization
  x86/smp: PM/hibernate: Split arch_resume_nosmt()
  intel_idle: Use subsys_initcall_sync() for initialization
parents 02adc149 dd358185

MAINTAINERS

+1 −0
Original line number Diff line number Diff line
@@ -6255,6 +6255,7 @@ F: include/linux/cpuhotplug.h 
F:	include/linux/smpboot.h

F:	kernel/cpu.c

F:	kernel/smpboot.*

F:	rust/helper/cpu.c

F:	rust/kernel/cpu.rs









CPU IDLE TIME MANAGEMENT FRAMEWORK
































arch/x86/kernel/smp.c



+24
−0






























Original line number
Diff line number
Diff line







@@ -299,3 +299,27 @@ struct smp_ops smp_ops = {







	.send_call_func_single_ipi = native_send_call_func_single_ipi,









};









EXPORT_SYMBOL_GPL(smp_ops);



















int arch_cpu_rescan_dead_smt_siblings(void)









{









	enum cpuhp_smt_control old = cpu_smt_control;









	int ret;



















	/*









	 * If SMT has been disabled and SMT siblings are in HLT, bring them back









	 * online and offline them again so that they end up in MWAIT proper.









	 *









	 * Called with hotplug enabled.









	 */









	if (old != CPU_SMT_DISABLED && old != CPU_SMT_FORCE_DISABLED)









		return 0;



















	ret = cpuhp_smt_enable();









	if (ret)









		return ret;



















	ret = cpuhp_smt_disable(old);



















	return ret;









}









EXPORT_SYMBOL_GPL(arch_cpu_rescan_dead_smt_siblings);
























arch/x86/kernel/smpboot.c



+7
−47






























Original line number
Diff line number
Diff line







@@ -1244,6 +1244,10 @@ void play_dead_common(void)







	local_irq_disable();









}



















/*









 * We need to flush the caches before going to sleep, lest we have









 * dirty data in our caches when we come back up.









 */









void __noreturn mwait_play_dead(unsigned int eax_hint)









{









	struct mwait_cpu_dead *md = this_cpu_ptr(&mwait_cpu_dead);








@@ -1289,50 +1293,6 @@ void __noreturn mwait_play_dead(unsigned int eax_hint)







	}









}



















/*









 * We need to flush the caches before going to sleep, lest we have









 * dirty data in our caches when we come back up.









 */









static inline void mwait_play_dead_cpuid_hint(void)









{









	unsigned int eax, ebx, ecx, edx;









	unsigned int highest_cstate = 0;









	unsigned int highest_subcstate = 0;









	int i;



















	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD ||









	    boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)









		return;









	if (!this_cpu_has(X86_FEATURE_MWAIT))









		return;









	if (!this_cpu_has(X86_FEATURE_CLFLUSH))









		return;



















	eax = CPUID_LEAF_MWAIT;









	ecx = 0;









	native_cpuid(&eax, &ebx, &ecx, &edx);



















	/*









	 * eax will be 0 if EDX enumeration is not valid.









	 * Initialized below to cstate, sub_cstate value when EDX is valid.









	 */









	if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED)) {









		eax = 0;









	} else {









		edx >>= MWAIT_SUBSTATE_SIZE;









		for (i = 0; i < 7 && edx; i++, edx >>= MWAIT_SUBSTATE_SIZE) {









			if (edx & MWAIT_SUBSTATE_MASK) {









				highest_cstate = i;









				highest_subcstate = edx & MWAIT_SUBSTATE_MASK;









			}









		}









		eax = (highest_cstate << MWAIT_SUBSTATE_SIZE) |









			(highest_subcstate - 1);









	}



















	mwait_play_dead(eax);









}



















/*









 * Kick all "offline" CPUs out of mwait on kexec(). See comment in









 * mwait_play_dead().








@@ -1383,8 +1343,8 @@ void native_play_dead(void)







	play_dead_common();









	tboot_shutdown(TB_SHUTDOWN_WFS);



















	mwait_play_dead_cpuid_hint();









	if (cpuidle_play_dead())









	/* Below returns only on error. */









	cpuidle_play_dead();









	hlt_play_dead();









}










































arch/x86/power/hibernate.c



+6
−13






























Original line number
Diff line number
Diff line







@@ -192,7 +192,8 @@ int relocate_restore_code(void)

















int arch_resume_nosmt(void)









{









	int ret = 0;









	int ret;



















	/*









	 * We reached this while coming out of hibernation. This means









	 * that SMT siblings are sleeping in hlt, as mwait is not safe








@@ -206,18 +207,10 @@ int arch_resume_nosmt(void)







	 * Called with hotplug disabled.









	 */









	cpu_hotplug_enable();









	if (cpu_smt_control == CPU_SMT_DISABLED ||









			cpu_smt_control == CPU_SMT_FORCE_DISABLED) {









		enum cpuhp_smt_control old = cpu_smt_control;



















		ret = cpuhp_smt_enable();









		if (ret)









			goto out;









		ret = cpuhp_smt_disable(old);









		if (ret)









			goto out;









	}









out:









	ret = arch_cpu_rescan_dead_smt_siblings();



















	cpu_hotplug_disable();



















	return ret;









}
























drivers/acpi/internal.h



+6
−0






























Original line number
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Diff line







@@ -175,6 +175,12 @@ bool processor_physically_present(acpi_handle handle);







static inline void acpi_early_processor_control_setup(void) {}









#endif



















#ifdef CONFIG_ACPI_PROCESSOR_CSTATE









void acpi_idle_rescan_dead_smt_siblings(void);









#else









static inline void acpi_idle_rescan_dead_smt_siblings(void) {}









#endif



















/* --------------------------------------------------------------------------









                                  Embedded Controller









   -------------------------------------------------------------------------- */