Add a boolean return to arch_trigger_cpumask_backtrace() to support a use-case where a particular architecture detects at runtime if it supports NMI backtrace or it would like to fallback to default implementation using SMP cross-calls.
Currently such an architecture example is arm64 supporting pseudo NMIs feature which is only available on platforms which have support for GICv3 or later version. Signed-off-by: Sumit Garg <sumit.g...@linaro.org> --- arch/arm/include/asm/irq.h | 2 +- arch/arm/kernel/smp.c | 3 ++- arch/mips/include/asm/irq.h | 2 +- arch/mips/kernel/process.c | 3 ++- arch/powerpc/include/asm/nmi.h | 2 +- arch/powerpc/kernel/stacktrace.c | 3 ++- arch/sparc/include/asm/irq_64.h | 2 +- arch/sparc/kernel/process_64.c | 4 +++- arch/x86/include/asm/irq.h | 2 +- arch/x86/kernel/apic/hw_nmi.c | 3 ++- include/linux/nmi.h | 12 ++++-------- 11 files changed, 20 insertions(+), 18 deletions(-) diff --git a/arch/arm/include/asm/irq.h b/arch/arm/include/asm/irq.h index 46d4114..54b0180 100644 --- a/arch/arm/include/asm/irq.h +++ b/arch/arm/include/asm/irq.h @@ -31,7 +31,7 @@ void handle_IRQ(unsigned int, struct pt_regs *); void init_IRQ(void); #ifdef CONFIG_SMP -extern void arch_trigger_cpumask_backtrace(const cpumask_t *mask, +extern bool arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self); #define arch_trigger_cpumask_backtrace arch_trigger_cpumask_backtrace #endif diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 48099c6e..bb20a43 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -856,7 +856,8 @@ static void raise_nmi(cpumask_t *mask) __ipi_send_mask(ipi_desc[IPI_CPU_BACKTRACE], mask); } -void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self) +bool arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self) { nmi_trigger_cpumask_backtrace(mask, exclude_self, raise_nmi); + return true; } diff --git a/arch/mips/include/asm/irq.h b/arch/mips/include/asm/irq.h index c5d3517..34f3b42 100644 --- a/arch/mips/include/asm/irq.h +++ b/arch/mips/include/asm/irq.h @@ -78,7 +78,7 @@ extern int cp0_fdc_irq; extern int get_c0_fdc_int(void); -void arch_trigger_cpumask_backtrace(const struct cpumask *mask, +bool arch_trigger_cpumask_backtrace(const struct cpumask *mask, bool exclude_self); #define arch_trigger_cpumask_backtrace arch_trigger_cpumask_backtrace diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c index 75ebd8d..d19e672 100644 --- a/arch/mips/kernel/process.c +++ b/arch/mips/kernel/process.c @@ -735,9 +735,10 @@ static void raise_backtrace(cpumask_t *mask) } } -void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self) +bool arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self) { nmi_trigger_cpumask_backtrace(mask, exclude_self, raise_backtrace); + return true; } int mips_get_process_fp_mode(struct task_struct *task) diff --git a/arch/powerpc/include/asm/nmi.h b/arch/powerpc/include/asm/nmi.h index 84b4cfe..a5eb3e2 100644 --- a/arch/powerpc/include/asm/nmi.h +++ b/arch/powerpc/include/asm/nmi.h @@ -9,7 +9,7 @@ static inline void arch_touch_nmi_watchdog(void) {} #endif #if defined(CONFIG_NMI_IPI) && defined(CONFIG_STACKTRACE) -extern void arch_trigger_cpumask_backtrace(const cpumask_t *mask, +extern bool arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self); #define arch_trigger_cpumask_backtrace arch_trigger_cpumask_backtrace #endif diff --git a/arch/powerpc/kernel/stacktrace.c b/arch/powerpc/kernel/stacktrace.c index b644065..22b112a 100644 --- a/arch/powerpc/kernel/stacktrace.c +++ b/arch/powerpc/kernel/stacktrace.c @@ -264,8 +264,9 @@ static void raise_backtrace_ipi(cpumask_t *mask) } } -void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self) +bool arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self) { nmi_trigger_cpumask_backtrace(mask, exclude_self, raise_backtrace_ipi); + return true; } #endif /* defined(CONFIG_PPC_BOOK3S_64) && defined(CONFIG_NMI_IPI) */ diff --git a/arch/sparc/include/asm/irq_64.h b/arch/sparc/include/asm/irq_64.h index 4d748e9..35c01ff 100644 --- a/arch/sparc/include/asm/irq_64.h +++ b/arch/sparc/include/asm/irq_64.h @@ -87,7 +87,7 @@ static inline unsigned long get_softint(void) return retval; } -void arch_trigger_cpumask_backtrace(const struct cpumask *mask, +bool arch_trigger_cpumask_backtrace(const struct cpumask *mask, bool exclude_self); #define arch_trigger_cpumask_backtrace arch_trigger_cpumask_backtrace diff --git a/arch/sparc/kernel/process_64.c b/arch/sparc/kernel/process_64.c index a75093b..9182001 100644 --- a/arch/sparc/kernel/process_64.c +++ b/arch/sparc/kernel/process_64.c @@ -248,7 +248,7 @@ static void __global_reg_poll(struct global_reg_snapshot *gp) } } -void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self) +bool arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self) { struct thread_info *tp = current_thread_info(); struct pt_regs *regs = get_irq_regs(); @@ -303,6 +303,8 @@ void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self) memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot)); spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags); + + return true; } #ifdef CONFIG_MAGIC_SYSRQ diff --git a/arch/x86/include/asm/irq.h b/arch/x86/include/asm/irq.h index 528c8a7..b7668e0 100644 --- a/arch/x86/include/asm/irq.h +++ b/arch/x86/include/asm/irq.h @@ -47,7 +47,7 @@ extern void init_ISA_irqs(void); extern void __init init_IRQ(void); #ifdef CONFIG_X86_LOCAL_APIC -void arch_trigger_cpumask_backtrace(const struct cpumask *mask, +bool arch_trigger_cpumask_backtrace(const struct cpumask *mask, bool exclude_self); #define arch_trigger_cpumask_backtrace arch_trigger_cpumask_backtrace diff --git a/arch/x86/kernel/apic/hw_nmi.c b/arch/x86/kernel/apic/hw_nmi.c index 34a992e..e7dcd28 100644 --- a/arch/x86/kernel/apic/hw_nmi.c +++ b/arch/x86/kernel/apic/hw_nmi.c @@ -34,10 +34,11 @@ static void nmi_raise_cpu_backtrace(cpumask_t *mask) apic->send_IPI_mask(mask, NMI_VECTOR); } -void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self) +bool arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self) { nmi_trigger_cpumask_backtrace(mask, exclude_self, nmi_raise_cpu_backtrace); + return true; } static int nmi_cpu_backtrace_handler(unsigned int cmd, struct pt_regs *regs) diff --git a/include/linux/nmi.h b/include/linux/nmi.h index 750c7f3..cedbfc1 100644 --- a/include/linux/nmi.h +++ b/include/linux/nmi.h @@ -143,26 +143,22 @@ static inline void touch_nmi_watchdog(void) #ifdef arch_trigger_cpumask_backtrace static inline bool trigger_all_cpu_backtrace(void) { - arch_trigger_cpumask_backtrace(cpu_online_mask, false); - return true; + return arch_trigger_cpumask_backtrace(cpu_online_mask, false); } static inline bool trigger_allbutself_cpu_backtrace(void) { - arch_trigger_cpumask_backtrace(cpu_online_mask, true); - return true; + return arch_trigger_cpumask_backtrace(cpu_online_mask, true); } static inline bool trigger_cpumask_backtrace(struct cpumask *mask) { - arch_trigger_cpumask_backtrace(mask, false); - return true; + return arch_trigger_cpumask_backtrace(mask, false); } static inline bool trigger_single_cpu_backtrace(int cpu) { - arch_trigger_cpumask_backtrace(cpumask_of(cpu), false); - return true; + return arch_trigger_cpumask_backtrace(cpumask_of(cpu), false); } /* generic implementation */ -- 2.7.4 _______________________________________________ Kgdb-bugreport mailing list Kgdb-bugreport@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kgdb-bugreport