From: Chris Metcalf <cmetcalf@xxxxxxxxxxxx> Subject: nmi_backtrace: generate one-line reports for idle cpus When doing an nmi backtrace of many cores, most of which are idle, the output is a little overwhelming and very uninformative. Suppress messages for cpus that are idling when they are interrupted and just emit one line, "NMI backtrace for N skipped: idling at pc 0xNNN". We do this by grouping all the cpuidle code together into a new .cpuidle.text section, and then checking the address of the interrupted PC to see if it lies within that section. This commit suitably tags x86 and tile idle routines, and only adds in the minimal framework for other architectures. Link: http://lkml.kernel.org/r/1472487169-14923-5-git-send-email-cmetcalf@xxxxxxxxxxxx Signed-off-by: Chris Metcalf <cmetcalf@xxxxxxxxxxxx> Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Tested-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Tested-by: Daniel Thompson <daniel.thompson@xxxxxxxxxx> [arm] Tested-by: Petr Mladek <pmladek@xxxxxxxx> Cc: Aaron Tomlin <atomlin@xxxxxxxxxx> Cc: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx> Cc: Russell King <linux@xxxxxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/alpha/kernel/vmlinux.lds.S | 1 + arch/arc/kernel/vmlinux.lds.S | 1 + arch/arm/kernel/vmlinux-xip.lds.S | 1 + arch/arm/kernel/vmlinux.lds.S | 1 + arch/arm64/kernel/vmlinux.lds.S | 1 + arch/avr32/kernel/vmlinux.lds.S | 1 + arch/blackfin/kernel/vmlinux.lds.S | 1 + arch/c6x/kernel/vmlinux.lds.S | 1 + arch/cris/kernel/vmlinux.lds.S | 1 + arch/frv/kernel/vmlinux.lds.S | 1 + arch/h8300/kernel/vmlinux.lds.S | 1 + arch/hexagon/kernel/vmlinux.lds.S | 1 + arch/ia64/kernel/vmlinux.lds.S | 1 + arch/m32r/kernel/vmlinux.lds.S | 1 + arch/m68k/kernel/vmlinux-nommu.lds | 1 + arch/m68k/kernel/vmlinux-std.lds | 1 + arch/m68k/kernel/vmlinux-sun3.lds | 1 + arch/metag/kernel/vmlinux.lds.S | 1 + arch/microblaze/kernel/vmlinux.lds.S | 1 + arch/mips/kernel/vmlinux.lds.S | 1 + arch/mn10300/kernel/vmlinux.lds.S | 1 + arch/nios2/kernel/vmlinux.lds.S | 1 + arch/openrisc/kernel/vmlinux.lds.S | 1 + arch/parisc/kernel/vmlinux.lds.S | 1 + arch/powerpc/kernel/vmlinux.lds.S | 1 + arch/s390/kernel/vmlinux.lds.S | 1 + arch/score/kernel/vmlinux.lds.S | 1 + arch/sh/kernel/vmlinux.lds.S | 1 + arch/sparc/kernel/vmlinux.lds.S | 1 + arch/tile/kernel/entry.S | 2 +- arch/tile/kernel/vmlinux.lds.S | 1 + arch/um/kernel/dyn.lds.S | 1 + arch/um/kernel/uml.lds.S | 1 + arch/unicore32/kernel/vmlinux.lds.S | 1 + arch/x86/include/asm/irqflags.h | 12 ++++++++---- arch/x86/kernel/acpi/cstate.c | 2 +- arch/x86/kernel/process.c | 4 ++-- arch/x86/kernel/vmlinux.lds.S | 1 + arch/xtensa/kernel/vmlinux.lds.S | 3 +++ drivers/acpi/processor_idle.c | 5 +++-- drivers/cpuidle/driver.c | 5 +++-- drivers/idle/intel_idle.c | 4 ++-- include/asm-generic/vmlinux.lds.h | 6 ++++++ include/linux/cpu.h | 5 +++++ kernel/sched/idle.c | 13 +++++++++++-- lib/nmi_backtrace.c | 16 +++++++++++----- scripts/mod/modpost.c | 2 +- scripts/recordmcount.c | 1 + scripts/recordmcount.pl | 1 + 49 files changed, 93 insertions(+), 22 deletions(-) diff -puN arch/alpha/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/alpha/kernel/vmlinux.lds.S --- a/arch/alpha/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/alpha/kernel/vmlinux.lds.S @@ -22,6 +22,7 @@ SECTIONS HEAD_TEXT TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT *(.fixup) *(.gnu.warning) diff -puN arch/arc/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/arc/kernel/vmlinux.lds.S --- a/arch/arc/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/arc/kernel/vmlinux.lds.S @@ -89,6 +89,7 @@ SECTIONS _text = .; TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT KPROBES_TEXT *(.fixup) diff -puN arch/arm/kernel/vmlinux-xip.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/arm/kernel/vmlinux-xip.lds.S --- a/arch/arm/kernel/vmlinux-xip.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/arm/kernel/vmlinux-xip.lds.S @@ -98,6 +98,7 @@ SECTIONS IRQENTRY_TEXT TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT KPROBES_TEXT *(.gnu.warning) diff -puN arch/arm/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/arm/kernel/vmlinux.lds.S --- a/arch/arm/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/arm/kernel/vmlinux.lds.S @@ -111,6 +111,7 @@ SECTIONS SOFTIRQENTRY_TEXT TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT HYPERVISOR_TEXT KPROBES_TEXT diff -puN arch/arm64/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/arm64/kernel/vmlinux.lds.S --- a/arch/arm64/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/arm64/kernel/vmlinux.lds.S @@ -122,6 +122,7 @@ SECTIONS ENTRY_TEXT TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT KPROBES_TEXT HYPERVISOR_TEXT diff -puN arch/avr32/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/avr32/kernel/vmlinux.lds.S --- a/arch/avr32/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/avr32/kernel/vmlinux.lds.S @@ -52,6 +52,7 @@ SECTIONS KPROBES_TEXT TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT *(.fixup) *(.gnu.warning) diff -puN arch/blackfin/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/blackfin/kernel/vmlinux.lds.S --- a/arch/blackfin/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/blackfin/kernel/vmlinux.lds.S @@ -33,6 +33,7 @@ SECTIONS #ifndef CONFIG_SCHEDULE_L1 SCHED_TEXT #endif + CPUIDLE_TEXT LOCK_TEXT IRQENTRY_TEXT SOFTIRQENTRY_TEXT diff -puN arch/c6x/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/c6x/kernel/vmlinux.lds.S --- a/arch/c6x/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/c6x/kernel/vmlinux.lds.S @@ -70,6 +70,7 @@ SECTIONS _stext = .; TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT IRQENTRY_TEXT SOFTIRQENTRY_TEXT diff -puN arch/cris/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/cris/kernel/vmlinux.lds.S --- a/arch/cris/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/cris/kernel/vmlinux.lds.S @@ -43,6 +43,7 @@ SECTIONS HEAD_TEXT TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT *(.fixup) *(.text.__*) diff -puN arch/frv/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/frv/kernel/vmlinux.lds.S --- a/arch/frv/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/frv/kernel/vmlinux.lds.S @@ -63,6 +63,7 @@ SECTIONS *(.text..tlbmiss) TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT #ifdef CONFIG_DEBUG_INFO INIT_TEXT diff -puN arch/h8300/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/h8300/kernel/vmlinux.lds.S --- a/arch/h8300/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/h8300/kernel/vmlinux.lds.S @@ -29,6 +29,7 @@ SECTIONS _stext = . ; TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT #if defined(CONFIG_ROMKERNEL) *(.int_redirect) diff -puN arch/hexagon/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/hexagon/kernel/vmlinux.lds.S --- a/arch/hexagon/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/hexagon/kernel/vmlinux.lds.S @@ -50,6 +50,7 @@ SECTIONS _text = .; TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT KPROBES_TEXT *(.fixup) diff -puN arch/ia64/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/ia64/kernel/vmlinux.lds.S --- a/arch/ia64/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/ia64/kernel/vmlinux.lds.S @@ -46,6 +46,7 @@ SECTIONS { __end_ivt_text = .; TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT KPROBES_TEXT *(.gnu.linkonce.t*) diff -puN arch/m32r/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/m32r/kernel/vmlinux.lds.S --- a/arch/m32r/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/m32r/kernel/vmlinux.lds.S @@ -31,6 +31,7 @@ SECTIONS HEAD_TEXT TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT *(.fixup) *(.gnu.warning) diff -puN arch/m68k/kernel/vmlinux-nommu.lds~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/m68k/kernel/vmlinux-nommu.lds --- a/arch/m68k/kernel/vmlinux-nommu.lds~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/m68k/kernel/vmlinux-nommu.lds @@ -45,6 +45,7 @@ SECTIONS { HEAD_TEXT TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT *(.fixup) . = ALIGN(16); diff -puN arch/m68k/kernel/vmlinux-std.lds~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/m68k/kernel/vmlinux-std.lds --- a/arch/m68k/kernel/vmlinux-std.lds~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/m68k/kernel/vmlinux-std.lds @@ -16,6 +16,7 @@ SECTIONS HEAD_TEXT TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT *(.fixup) *(.gnu.warning) diff -puN arch/m68k/kernel/vmlinux-sun3.lds~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/m68k/kernel/vmlinux-sun3.lds --- a/arch/m68k/kernel/vmlinux-sun3.lds~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/m68k/kernel/vmlinux-sun3.lds @@ -16,6 +16,7 @@ SECTIONS HEAD_TEXT TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT *(.fixup) *(.gnu.warning) diff -puN arch/metag/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/metag/kernel/vmlinux.lds.S --- a/arch/metag/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/metag/kernel/vmlinux.lds.S @@ -21,6 +21,7 @@ SECTIONS .text : { TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT KPROBES_TEXT IRQENTRY_TEXT diff -puN arch/microblaze/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/microblaze/kernel/vmlinux.lds.S --- a/arch/microblaze/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/microblaze/kernel/vmlinux.lds.S @@ -33,6 +33,7 @@ SECTIONS { EXIT_TEXT EXIT_CALL SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT KPROBES_TEXT IRQENTRY_TEXT diff -puN arch/mips/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/mips/kernel/vmlinux.lds.S --- a/arch/mips/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/mips/kernel/vmlinux.lds.S @@ -55,6 +55,7 @@ SECTIONS .text : { TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT KPROBES_TEXT IRQENTRY_TEXT diff -puN arch/mn10300/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/mn10300/kernel/vmlinux.lds.S --- a/arch/mn10300/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/mn10300/kernel/vmlinux.lds.S @@ -30,6 +30,7 @@ SECTIONS HEAD_TEXT TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT KPROBES_TEXT *(.fixup) diff -puN arch/nios2/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/nios2/kernel/vmlinux.lds.S --- a/arch/nios2/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/nios2/kernel/vmlinux.lds.S @@ -37,6 +37,7 @@ SECTIONS .text : { TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT IRQENTRY_TEXT SOFTIRQENTRY_TEXT diff -puN arch/openrisc/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/openrisc/kernel/vmlinux.lds.S --- a/arch/openrisc/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/openrisc/kernel/vmlinux.lds.S @@ -47,6 +47,7 @@ SECTIONS _stext = .; TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT KPROBES_TEXT IRQENTRY_TEXT diff -puN arch/parisc/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/parisc/kernel/vmlinux.lds.S --- a/arch/parisc/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/parisc/kernel/vmlinux.lds.S @@ -69,6 +69,7 @@ SECTIONS .text ALIGN(PAGE_SIZE) : { TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT KPROBES_TEXT IRQENTRY_TEXT diff -puN arch/powerpc/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/powerpc/kernel/vmlinux.lds.S --- a/arch/powerpc/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/powerpc/kernel/vmlinux.lds.S @@ -52,6 +52,7 @@ SECTIONS /* careful! __ftr_alt_* sections need to be close to .text */ *(.text .fixup __ftr_alt_* .ref.text) SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT KPROBES_TEXT IRQENTRY_TEXT diff -puN arch/s390/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/s390/kernel/vmlinux.lds.S --- a/arch/s390/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/s390/kernel/vmlinux.lds.S @@ -35,6 +35,7 @@ SECTIONS HEAD_TEXT TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT KPROBES_TEXT IRQENTRY_TEXT diff -puN arch/score/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/score/kernel/vmlinux.lds.S --- a/arch/score/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/score/kernel/vmlinux.lds.S @@ -40,6 +40,7 @@ SECTIONS _text = .; /* Text and read-only data */ TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT KPROBES_TEXT *(.text.*) diff -puN arch/sh/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/sh/kernel/vmlinux.lds.S --- a/arch/sh/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/sh/kernel/vmlinux.lds.S @@ -36,6 +36,7 @@ SECTIONS TEXT_TEXT EXTRA_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT KPROBES_TEXT IRQENTRY_TEXT diff -puN arch/sparc/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/sparc/kernel/vmlinux.lds.S --- a/arch/sparc/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/sparc/kernel/vmlinux.lds.S @@ -49,6 +49,7 @@ SECTIONS HEAD_TEXT TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT KPROBES_TEXT IRQENTRY_TEXT diff -puN arch/tile/kernel/entry.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/tile/kernel/entry.S --- a/arch/tile/kernel/entry.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/tile/kernel/entry.S @@ -50,7 +50,7 @@ STD_ENTRY(smp_nap) * When interrupted at _cpu_idle_nap, we bump the PC forward 8, and * as a result return to the function that called _cpu_idle(). */ -STD_ENTRY(_cpu_idle) +STD_ENTRY_SECTION(_cpu_idle, .cpuidle.text) movei r1, 1 IRQ_ENABLE_LOAD(r2, r3) mtspr INTERRUPT_CRITICAL_SECTION, r1 diff -puN arch/tile/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/tile/kernel/vmlinux.lds.S --- a/arch/tile/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/tile/kernel/vmlinux.lds.S @@ -42,6 +42,7 @@ SECTIONS .text : AT (ADDR(.text) - LOAD_OFFSET) { HEAD_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT KPROBES_TEXT IRQENTRY_TEXT diff -puN arch/um/kernel/dyn.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/um/kernel/dyn.lds.S --- a/arch/um/kernel/dyn.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/um/kernel/dyn.lds.S @@ -68,6 +68,7 @@ SECTIONS _stext = .; TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT *(.fixup) *(.stub .text.* .gnu.linkonce.t.*) diff -puN arch/um/kernel/uml.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/um/kernel/uml.lds.S --- a/arch/um/kernel/uml.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/um/kernel/uml.lds.S @@ -28,6 +28,7 @@ SECTIONS _stext = .; TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT *(.fixup) /* .gnu.warning sections are handled specially by elf32.em. */ diff -puN arch/unicore32/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/unicore32/kernel/vmlinux.lds.S --- a/arch/unicore32/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/unicore32/kernel/vmlinux.lds.S @@ -37,6 +37,7 @@ SECTIONS .text : { /* Real text segment */ TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT *(.fixup) diff -puN arch/x86/include/asm/irqflags.h~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/x86/include/asm/irqflags.h --- a/arch/x86/include/asm/irqflags.h~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/x86/include/asm/irqflags.h @@ -4,6 +4,10 @@ #include <asm/processor-flags.h> #ifndef __ASSEMBLY__ + +/* Provide __cpuidle; we can't safely include <linux/cpu.h> */ +#define __cpuidle __attribute__((__section__(".cpuidle.text"))) + /* * Interrupt control: */ @@ -44,12 +48,12 @@ static inline void native_irq_enable(voi asm volatile("sti": : :"memory"); } -static inline void native_safe_halt(void) +static inline __cpuidle void native_safe_halt(void) { asm volatile("sti; hlt": : :"memory"); } -static inline void native_halt(void) +static inline __cpuidle void native_halt(void) { asm volatile("hlt": : :"memory"); } @@ -86,7 +90,7 @@ static inline notrace void arch_local_ir * Used in the idle loop; sti takes one instruction cycle * to complete: */ -static inline void arch_safe_halt(void) +static inline __cpuidle void arch_safe_halt(void) { native_safe_halt(); } @@ -95,7 +99,7 @@ static inline void arch_safe_halt(void) * Used when interrupts are already enabled or to * shutdown the processor: */ -static inline void halt(void) +static inline __cpuidle void halt(void) { native_halt(); } diff -puN arch/x86/kernel/acpi/cstate.c~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/x86/kernel/acpi/cstate.c --- a/arch/x86/kernel/acpi/cstate.c~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/x86/kernel/acpi/cstate.c @@ -152,7 +152,7 @@ int acpi_processor_ffh_cstate_probe(unsi } EXPORT_SYMBOL_GPL(acpi_processor_ffh_cstate_probe); -void acpi_processor_ffh_cstate_enter(struct acpi_processor_cx *cx) +void __cpuidle acpi_processor_ffh_cstate_enter(struct acpi_processor_cx *cx) { unsigned int cpu = smp_processor_id(); struct cstate_entry *percpu_entry; diff -puN arch/x86/kernel/process.c~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/x86/kernel/process.c --- a/arch/x86/kernel/process.c~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/x86/kernel/process.c @@ -302,7 +302,7 @@ void arch_cpu_idle(void) /* * We use this if we don't have any better idle routine.. */ -void default_idle(void) +void __cpuidle default_idle(void) { trace_cpu_idle_rcuidle(1, smp_processor_id()); safe_halt(); @@ -417,7 +417,7 @@ static int prefer_mwait_c1_over_halt(con * with interrupts enabled and no flags, which is backwards compatible with the * original MWAIT implementation. */ -static void mwait_idle(void) +static __cpuidle void mwait_idle(void) { if (!current_set_polling_and_test()) { trace_cpu_idle_rcuidle(1, smp_processor_id()); diff -puN arch/x86/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/x86/kernel/vmlinux.lds.S --- a/arch/x86/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/x86/kernel/vmlinux.lds.S @@ -97,6 +97,7 @@ SECTIONS _stext = .; TEXT_TEXT SCHED_TEXT + CPUIDLE_TEXT LOCK_TEXT KPROBES_TEXT ENTRY_TEXT diff -puN arch/xtensa/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus arch/xtensa/kernel/vmlinux.lds.S --- a/arch/xtensa/kernel/vmlinux.lds.S~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/arch/xtensa/kernel/vmlinux.lds.S @@ -89,6 +89,9 @@ SECTIONS VMLINUX_SYMBOL(__sched_text_start) = .; *(.sched.literal .sched.text) VMLINUX_SYMBOL(__sched_text_end) = .; + VMLINUX_SYMBOL(__cpuidle_text_start) = .; + *(.cpuidle.literal .cpuidle.text) + VMLINUX_SYMBOL(__cpuidle_text_end) = .; VMLINUX_SYMBOL(__lock_text_start) = .; *(.spinlock.literal .spinlock.text) VMLINUX_SYMBOL(__lock_text_end) = .; diff -puN drivers/acpi/processor_idle.c~nmi_backtrace-generate-one-line-reports-for-idle-cpus drivers/acpi/processor_idle.c --- a/drivers/acpi/processor_idle.c~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/drivers/acpi/processor_idle.c @@ -31,6 +31,7 @@ #include <linux/sched.h> /* need_resched() */ #include <linux/tick.h> #include <linux/cpuidle.h> +#include <linux/cpu.h> #include <acpi/processor.h> /* @@ -115,7 +116,7 @@ static const struct dmi_system_id proces * Callers should disable interrupts before the call and enable * interrupts after return. */ -static void acpi_safe_halt(void) +static void __cpuidle acpi_safe_halt(void) { if (!tif_need_resched()) { safe_halt(); @@ -645,7 +646,7 @@ static int acpi_idle_bm_check(void) * * Caller disables interrupt before call and enables interrupt after return. */ -static void acpi_idle_do_entry(struct acpi_processor_cx *cx) +static void __cpuidle acpi_idle_do_entry(struct acpi_processor_cx *cx) { if (cx->entry_method == ACPI_CSTATE_FFH) { /* Call into architectural FFH based C-state */ diff -puN drivers/cpuidle/driver.c~nmi_backtrace-generate-one-line-reports-for-idle-cpus drivers/cpuidle/driver.c --- a/drivers/cpuidle/driver.c~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/drivers/cpuidle/driver.c @@ -14,6 +14,7 @@ #include <linux/cpuidle.h> #include <linux/cpumask.h> #include <linux/tick.h> +#include <linux/cpu.h> #include "cpuidle.h" @@ -178,8 +179,8 @@ static void __cpuidle_driver_init(struct } #ifdef CONFIG_ARCH_HAS_CPU_RELAX -static int poll_idle(struct cpuidle_device *dev, - struct cpuidle_driver *drv, int index) +static int __cpuidle poll_idle(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) { local_irq_enable(); if (!current_set_polling_and_test()) { diff -puN drivers/idle/intel_idle.c~nmi_backtrace-generate-one-line-reports-for-idle-cpus drivers/idle/intel_idle.c --- a/drivers/idle/intel_idle.c~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/drivers/idle/intel_idle.c @@ -863,8 +863,8 @@ static struct cpuidle_state dnv_cstates[ * * Must be called under local_irq_disable(). */ -static int intel_idle(struct cpuidle_device *dev, - struct cpuidle_driver *drv, int index) +static __cpuidle int intel_idle(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) { unsigned long ecx = 1; /* break on interrupt flag */ struct cpuidle_state *state = &drv->states[index]; diff -puN include/asm-generic/vmlinux.lds.h~nmi_backtrace-generate-one-line-reports-for-idle-cpus include/asm-generic/vmlinux.lds.h --- a/include/asm-generic/vmlinux.lds.h~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/include/asm-generic/vmlinux.lds.h @@ -454,6 +454,12 @@ *(.spinlock.text) \ VMLINUX_SYMBOL(__lock_text_end) = .; +#define CPUIDLE_TEXT \ + ALIGN_FUNCTION(); \ + VMLINUX_SYMBOL(__cpuidle_text_start) = .; \ + *(.cpuidle.text) \ + VMLINUX_SYMBOL(__cpuidle_text_end) = .; + #define KPROBES_TEXT \ ALIGN_FUNCTION(); \ VMLINUX_SYMBOL(__kprobes_text_start) = .; \ diff -puN include/linux/cpu.h~nmi_backtrace-generate-one-line-reports-for-idle-cpus include/linux/cpu.h --- a/include/linux/cpu.h~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/include/linux/cpu.h @@ -231,6 +231,11 @@ void cpu_startup_entry(enum cpuhp_state void cpu_idle_poll_ctrl(bool enable); +/* Attach to any functions which should be considered cpuidle. */ +#define __cpuidle __attribute__((__section__(".cpuidle.text"))) + +bool cpu_in_idle(unsigned long pc); + void arch_cpu_idle(void); void arch_cpu_idle_prepare(void); void arch_cpu_idle_enter(void); diff -puN kernel/sched/idle.c~nmi_backtrace-generate-one-line-reports-for-idle-cpus kernel/sched/idle.c --- a/kernel/sched/idle.c~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/kernel/sched/idle.c @@ -16,6 +16,9 @@ #include "sched.h" +/* Linker adds these: start and end of __cpuidle functions */ +extern char __cpuidle_text_start[], __cpuidle_text_end[]; + /** * sched_idle_set_state - Record idle state for the current CPU. * @idle_state: State to record. @@ -53,7 +56,7 @@ static int __init cpu_idle_nopoll_setup( __setup("hlt", cpu_idle_nopoll_setup); #endif -static inline int cpu_idle_poll(void) +static noinline int __cpuidle cpu_idle_poll(void) { rcu_idle_enter(); trace_cpu_idle_rcuidle(0, smp_processor_id()); @@ -84,7 +87,7 @@ void __weak arch_cpu_idle(void) * * To use when the cpuidle framework cannot be used. */ -void default_idle_call(void) +void __cpuidle default_idle_call(void) { if (current_clr_polling_and_test()) { local_irq_enable(); @@ -271,6 +274,12 @@ static void cpu_idle_loop(void) } } +bool cpu_in_idle(unsigned long pc) +{ + return pc >= (unsigned long)__cpuidle_text_start && + pc < (unsigned long)__cpuidle_text_end; +} + void cpu_startup_entry(enum cpuhp_state state) { /* diff -puN lib/nmi_backtrace.c~nmi_backtrace-generate-one-line-reports-for-idle-cpus lib/nmi_backtrace.c --- a/lib/nmi_backtrace.c~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/lib/nmi_backtrace.c @@ -16,6 +16,7 @@ #include <linux/delay.h> #include <linux/kprobes.h> #include <linux/nmi.h> +#include <linux/cpu.h> #ifdef arch_trigger_cpumask_backtrace /* For reliability, we're prepared to waste bits here. */ @@ -87,11 +88,16 @@ bool nmi_cpu_backtrace(struct pt_regs *r int cpu = smp_processor_id(); if (cpumask_test_cpu(cpu, to_cpumask(backtrace_mask))) { - pr_warn("NMI backtrace for cpu %d\n", cpu); - if (regs) - show_regs(regs); - else - dump_stack(); + if (regs && cpu_in_idle(instruction_pointer(regs))) { + pr_warn("NMI backtrace for cpu %d skipped: idling at pc %#lx\n", + cpu, instruction_pointer(regs)); + } else { + pr_warn("NMI backtrace for cpu %d\n", cpu); + if (regs) + show_regs(regs); + else + dump_stack(); + } cpumask_clear_cpu(cpu, to_cpumask(backtrace_mask)); return true; } diff -puN scripts/mod/modpost.c~nmi_backtrace-generate-one-line-reports-for-idle-cpus scripts/mod/modpost.c --- a/scripts/mod/modpost.c~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/scripts/mod/modpost.c @@ -888,7 +888,7 @@ static void check_section(const char *mo #define DATA_SECTIONS ".data", ".data.rel" #define TEXT_SECTIONS ".text", ".text.unlikely", ".sched.text", \ - ".kprobes.text" + ".kprobes.text", ".cpuidle.text" #define OTHER_TEXT_SECTIONS ".ref.text", ".head.text", ".spinlock.text", \ ".fixup", ".entry.text", ".exception.text", ".text.*", \ ".coldtext" diff -puN scripts/recordmcount.c~nmi_backtrace-generate-one-line-reports-for-idle-cpus scripts/recordmcount.c --- a/scripts/recordmcount.c~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/scripts/recordmcount.c @@ -365,6 +365,7 @@ is_mcounted_section_name(char const *con strcmp(".irqentry.text", txtname) == 0 || strcmp(".softirqentry.text", txtname) == 0 || strcmp(".kprobes.text", txtname) == 0 || + strcmp(".cpuidle.text", txtname) == 0 || strcmp(".text.unlikely", txtname) == 0; } diff -puN scripts/recordmcount.pl~nmi_backtrace-generate-one-line-reports-for-idle-cpus scripts/recordmcount.pl --- a/scripts/recordmcount.pl~nmi_backtrace-generate-one-line-reports-for-idle-cpus +++ a/scripts/recordmcount.pl @@ -136,6 +136,7 @@ my %text_sections = ( ".irqentry.text" => 1, ".softirqentry.text" => 1, ".kprobes.text" => 1, + ".cpuidle.text" => 1, ".text.unlikely" => 1, ); _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
