The following commit has been merged into the sched/core branch of tip: Commit-ID: e4df1511e1f4bcaa0d590aa7bbffe8bbbd6dfb49 Gitweb: https://git.kernel.org/tip/e4df1511e1f4bcaa0d590aa7bbffe8bbbd6dfb49 Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx> AuthorDate: Thu, 12 Jan 2023 20:43:41 +01:00 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitterDate: Fri, 13 Jan 2023 11:48:16 +01:00 cpuidle, sched: Remove instrumentation from TIF_{POLLING_NRFLAG,NEED_RESCHED} objtool pointed out that various idle-TIF management methods have instrumentation: vmlinux.o: warning: objtool: mwait_idle+0x5: call to current_set_polling_and_test() leaves .noinstr.text section vmlinux.o: warning: objtool: acpi_processor_ffh_cstate_enter+0xc5: call to current_set_polling_and_test() leaves .noinstr.text section vmlinux.o: warning: objtool: cpu_idle_poll.isra.0+0x73: call to test_ti_thread_flag() leaves .noinstr.text section vmlinux.o: warning: objtool: intel_idle+0xbc: call to current_set_polling_and_test() leaves .noinstr.text section vmlinux.o: warning: objtool: intel_idle_irq+0xea: call to current_set_polling_and_test() leaves .noinstr.text section vmlinux.o: warning: objtool: intel_idle_s2idle+0xb4: call to current_set_polling_and_test() leaves .noinstr.text section vmlinux.o: warning: objtool: intel_idle+0xa6: call to current_clr_polling() leaves .noinstr.text section vmlinux.o: warning: objtool: intel_idle_irq+0xbf: call to current_clr_polling() leaves .noinstr.text section vmlinux.o: warning: objtool: intel_idle_s2idle+0xa1: call to current_clr_polling() leaves .noinstr.text section vmlinux.o: warning: objtool: mwait_idle+0xe: call to __current_set_polling() leaves .noinstr.text section vmlinux.o: warning: objtool: acpi_processor_ffh_cstate_enter+0xc5: call to __current_set_polling() leaves .noinstr.text section vmlinux.o: warning: objtool: cpu_idle_poll.isra.0+0x73: call to test_ti_thread_flag() leaves .noinstr.text section vmlinux.o: warning: objtool: intel_idle+0xbc: call to __current_set_polling() leaves .noinstr.text section vmlinux.o: warning: objtool: intel_idle_irq+0xea: call to __current_set_polling() leaves .noinstr.text section vmlinux.o: warning: objtool: intel_idle_s2idle+0xb4: call to __current_set_polling() leaves .noinstr.text section vmlinux.o: warning: objtool: cpu_idle_poll.isra.0+0x73: call to test_ti_thread_flag() leaves .noinstr.text section vmlinux.o: warning: objtool: intel_idle_s2idle+0x73: call to test_ti_thread_flag.constprop.0() leaves .noinstr.text section vmlinux.o: warning: objtool: intel_idle_irq+0x91: call to test_ti_thread_flag.constprop.0() leaves .noinstr.text section vmlinux.o: warning: objtool: intel_idle+0x78: call to test_ti_thread_flag.constprop.0() leaves .noinstr.text section vmlinux.o: warning: objtool: acpi_safe_halt+0xf: call to test_ti_thread_flag.constprop.0() leaves .noinstr.text section Remove the instrumentation, because these methods are used in low-level cpuidle code moving between states, that should not be instrumented. Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> Tested-by: Tony Lindgren <tony@xxxxxxxxxxx> Tested-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Acked-by: Frederic Weisbecker <frederic@xxxxxxxxxx> Link: https://lore.kernel.org/r/20230112195540.988741683@xxxxxxxxxxxxx --- include/linux/sched/idle.h | 40 +++++++++++++++++++++++++++--------- include/linux/thread_info.h | 18 +++++++++++++++- 2 files changed, 47 insertions(+), 11 deletions(-) diff --git a/include/linux/sched/idle.h b/include/linux/sched/idle.h index d73d314..478084f 100644 --- a/include/linux/sched/idle.h +++ b/include/linux/sched/idle.h @@ -23,12 +23,37 @@ static inline void wake_up_if_idle(int cpu) { } */ #ifdef TIF_POLLING_NRFLAG -static inline void __current_set_polling(void) +#ifdef _ASM_GENERIC_BITOPS_INSTRUMENTED_ATOMIC_H + +static __always_inline void __current_set_polling(void) { - set_thread_flag(TIF_POLLING_NRFLAG); + arch_set_bit(TIF_POLLING_NRFLAG, + (unsigned long *)(¤t_thread_info()->flags)); } -static inline bool __must_check current_set_polling_and_test(void) +static __always_inline void __current_clr_polling(void) +{ + arch_clear_bit(TIF_POLLING_NRFLAG, + (unsigned long *)(¤t_thread_info()->flags)); +} + +#else + +static __always_inline void __current_set_polling(void) +{ + set_bit(TIF_POLLING_NRFLAG, + (unsigned long *)(¤t_thread_info()->flags)); +} + +static __always_inline void __current_clr_polling(void) +{ + clear_bit(TIF_POLLING_NRFLAG, + (unsigned long *)(¤t_thread_info()->flags)); +} + +#endif /* _ASM_GENERIC_BITOPS_INSTRUMENTED_ATOMIC_H */ + +static __always_inline bool __must_check current_set_polling_and_test(void) { __current_set_polling(); @@ -41,12 +66,7 @@ static inline bool __must_check current_set_polling_and_test(void) return unlikely(tif_need_resched()); } -static inline void __current_clr_polling(void) -{ - clear_thread_flag(TIF_POLLING_NRFLAG); -} - -static inline bool __must_check current_clr_polling_and_test(void) +static __always_inline bool __must_check current_clr_polling_and_test(void) { __current_clr_polling(); @@ -73,7 +93,7 @@ static inline bool __must_check current_clr_polling_and_test(void) } #endif -static inline void current_clr_polling(void) +static __always_inline void current_clr_polling(void) { __current_clr_polling(); diff --git a/include/linux/thread_info.h b/include/linux/thread_info.h index 9f392ec..c026468 100644 --- a/include/linux/thread_info.h +++ b/include/linux/thread_info.h @@ -177,7 +177,23 @@ static __always_inline unsigned long read_ti_thread_flags(struct thread_info *ti clear_ti_thread_flag(task_thread_info(t), TIF_##fl) #endif /* !CONFIG_GENERIC_ENTRY */ -#define tif_need_resched() test_thread_flag(TIF_NEED_RESCHED) +#ifdef _ASM_GENERIC_BITOPS_INSTRUMENTED_NON_ATOMIC_H + +static __always_inline bool tif_need_resched(void) +{ + return arch_test_bit(TIF_NEED_RESCHED, + (unsigned long *)(¤t_thread_info()->flags)); +} + +#else + +static __always_inline bool tif_need_resched(void) +{ + return test_bit(TIF_NEED_RESCHED, + (unsigned long *)(¤t_thread_info()->flags)); +} + +#endif /* _ASM_GENERIC_BITOPS_INSTRUMENTED_NON_ATOMIC_H */ #ifndef CONFIG_HAVE_ARCH_WITHIN_STACK_FRAMES static inline int arch_within_stack_frames(const void * const stack,
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