This is required in order to allow more significant differences between NMI type interrupt handlers and regular asynchronous handlers.
Signed-off-by: Nicholas Piggin <npig...@gmail.com> --- arch/powerpc/kernel/traps.c | 31 +++++++++++++++++++++++++++- arch/powerpc/perf/core-book3s.c | 35 ++------------------------------ arch/powerpc/perf/core-fsl-emb.c | 25 ----------------------- 3 files changed, 32 insertions(+), 59 deletions(-) diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 902fcbd1a778..7dda72eb97cc 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -1919,11 +1919,40 @@ void vsx_unavailable_tm(struct pt_regs *regs) } #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */ -void performance_monitor_exception(struct pt_regs *regs) +static void performance_monitor_exception_nmi(struct pt_regs *regs) +{ + nmi_enter(); + + __this_cpu_inc(irq_stat.pmu_irqs); + + perf_irq(regs); + + nmi_exit(); +} + +static void performance_monitor_exception_async(struct pt_regs *regs) { + irq_enter(); + __this_cpu_inc(irq_stat.pmu_irqs); perf_irq(regs); + + irq_exit(); +} + +void performance_monitor_exception(struct pt_regs *regs) +{ + /* + * On 64-bit, if perf interrupts hit in a local_irq_disable + * (soft-masked) region, we consider them as NMIs. This is required to + * prevent hash faults on user addresses when reading callchains (and + * looks better from an irq tracing perspective). + */ + if (IS_ENABLED(CONFIG_PPC64) && unlikely(arch_irq_disabled_regs(regs))) + performance_monitor_exception_nmi(regs); + else + performance_monitor_exception_async(regs); } #ifdef CONFIG_PPC_ADV_DEBUG_REGS diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c index 08643cba1494..9fd8cae09218 100644 --- a/arch/powerpc/perf/core-book3s.c +++ b/arch/powerpc/perf/core-book3s.c @@ -109,10 +109,6 @@ static inline void perf_read_regs(struct pt_regs *regs) { regs->result = 0; } -static inline int perf_intr_is_nmi(struct pt_regs *regs) -{ - return 0; -} static inline int siar_valid(struct pt_regs *regs) { @@ -328,15 +324,6 @@ static inline void perf_read_regs(struct pt_regs *regs) regs->result = use_siar; } -/* - * If interrupts were soft-disabled when a PMU interrupt occurs, treat - * it as an NMI. - */ -static inline int perf_intr_is_nmi(struct pt_regs *regs) -{ - return (regs->softe & IRQS_DISABLED); -} - /* * On processors like P7+ that have the SIAR-Valid bit, marked instructions * must be sampled only if the SIAR-valid bit is set. @@ -2224,7 +2211,6 @@ static void __perf_event_interrupt(struct pt_regs *regs) struct perf_event *event; unsigned long val[8]; int found, active; - int nmi; if (cpuhw->n_limited) freeze_limited_counters(cpuhw, mfspr(SPRN_PMC5), @@ -2232,18 +2218,6 @@ static void __perf_event_interrupt(struct pt_regs *regs) perf_read_regs(regs); - /* - * If perf interrupts hit in a local_irq_disable (soft-masked) region, - * we consider them as NMIs. This is required to prevent hash faults on - * user addresses when reading callchains. See the NMI test in - * do_hash_page. - */ - nmi = perf_intr_is_nmi(regs); - if (nmi) - nmi_enter(); - else - irq_enter(); - /* Read all the PMCs since we'll need them a bunch of times */ for (i = 0; i < ppmu->n_counter; ++i) val[i] = read_pmc(i + 1); @@ -2289,8 +2263,8 @@ static void __perf_event_interrupt(struct pt_regs *regs) } } } - if (!found && !nmi && printk_ratelimit()) - printk(KERN_WARNING "Can't find PMC that caused IRQ\n"); + if (unlikely(!found) && !arch_irq_disabled_regs(regs)) + printk_ratelimited(KERN_WARNING "Can't find PMC that caused IRQ\n"); /* * Reset MMCR0 to its normal value. This will set PMXE and @@ -2300,11 +2274,6 @@ static void __perf_event_interrupt(struct pt_regs *regs) * we get back out of this interrupt. */ write_mmcr0(cpuhw, cpuhw->mmcr.mmcr0); - - if (nmi) - nmi_exit(); - else - irq_exit(); } static void perf_event_interrupt(struct pt_regs *regs) diff --git a/arch/powerpc/perf/core-fsl-emb.c b/arch/powerpc/perf/core-fsl-emb.c index e0e7e276bfd2..ee721f420a7b 100644 --- a/arch/powerpc/perf/core-fsl-emb.c +++ b/arch/powerpc/perf/core-fsl-emb.c @@ -31,19 +31,6 @@ static atomic_t num_events; /* Used to avoid races in calling reserve/release_pmc_hardware */ static DEFINE_MUTEX(pmc_reserve_mutex); -/* - * If interrupts were soft-disabled when a PMU interrupt occurs, treat - * it as an NMI. - */ -static inline int perf_intr_is_nmi(struct pt_regs *regs) -{ -#ifdef __powerpc64__ - return (regs->softe & IRQS_DISABLED); -#else - return 0; -#endif -} - static void perf_event_interrupt(struct pt_regs *regs); /* @@ -659,13 +646,6 @@ static void perf_event_interrupt(struct pt_regs *regs) struct perf_event *event; unsigned long val; int found = 0; - int nmi; - - nmi = perf_intr_is_nmi(regs); - if (nmi) - nmi_enter(); - else - irq_enter(); for (i = 0; i < ppmu->n_counter; ++i) { event = cpuhw->event[i]; @@ -690,11 +670,6 @@ static void perf_event_interrupt(struct pt_regs *regs) mtmsr(mfmsr() | MSR_PMM); mtpmr(PMRN_PMGC0, PMGC0_PMIE | PMGC0_FCECE); isync(); - - if (nmi) - nmi_exit(); - else - irq_exit(); } void hw_perf_event_setup(int cpu) -- 2.23.0