diff options
| -rw-r--r-- | arch/xtensa/Kconfig | 16 | ||||
| -rw-r--r-- | arch/xtensa/include/asm/processor.h | 12 | ||||
| -rw-r--r-- | arch/xtensa/kernel/traps.c | 27 |
3 files changed, 48 insertions, 7 deletions
diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig index 82044f732323..128e63d3a632 100644 --- a/arch/xtensa/Kconfig +++ b/arch/xtensa/Kconfig @@ -139,6 +139,22 @@ config XTENSA_VARIANT_HAVE_PERF_EVENTS If unsure, say N. +config XTENSA_FAKE_NMI + bool "Treat PMM IRQ as NMI" + depends on XTENSA_VARIANT_HAVE_PERF_EVENTS + default n + help + If PMM IRQ is the only IRQ at EXCM level it is safe to + treat it as NMI, which improves accuracy of profiling. + + If there are other interrupts at or above PMM IRQ priority level + but not above the EXCM level, PMM IRQ still may be treated as NMI, + but only if these IRQs are not used. There will be a build warning + saying that this is not safe, and a bugcheck if one of these IRQs + actually fire. + + If unsure, say N. + config XTENSA_UNALIGNED_USER bool "Unaligned memory access in use space" help diff --git a/arch/xtensa/include/asm/processor.h b/arch/xtensa/include/asm/processor.h index 83e2e4bc01ba..744ecf0dc3a4 100644 --- a/arch/xtensa/include/asm/processor.h +++ b/arch/xtensa/include/asm/processor.h @@ -78,22 +78,20 @@ #define XTENSA_INTLEVEL_MASK(level) _XTENSA_INTLEVEL_MASK(level) #define _XTENSA_INTLEVEL_MASK(level) (XCHAL_INTLEVEL##level##_MASK) -#define IS_POW2(v) (((v) & ((v) - 1)) == 0) +#define XTENSA_INTLEVEL_ANDBELOW_MASK(l) _XTENSA_INTLEVEL_ANDBELOW_MASK(l) +#define _XTENSA_INTLEVEL_ANDBELOW_MASK(l) (XCHAL_INTLEVEL##l##_ANDBELOW_MASK) #define PROFILING_INTLEVEL XTENSA_INT_LEVEL(XCHAL_PROFILING_INTERRUPT) /* LOCKLEVEL defines the interrupt level that masks all * general-purpose interrupts. */ -#if defined(CONFIG_XTENSA_VARIANT_HAVE_PERF_EVENTS) && \ - defined(XCHAL_PROFILING_INTERRUPT) && \ - PROFILING_INTLEVEL == XCHAL_EXCM_LEVEL && \ - XCHAL_EXCM_LEVEL > 1 && \ - IS_POW2(XTENSA_INTLEVEL_MASK(PROFILING_INTLEVEL)) -#define LOCKLEVEL (XCHAL_EXCM_LEVEL - 1) +#if defined(CONFIG_XTENSA_FAKE_NMI) && defined(XCHAL_PROFILING_INTERRUPT) +#define LOCKLEVEL (PROFILING_INTLEVEL - 1) #else #define LOCKLEVEL XCHAL_EXCM_LEVEL #endif + #define TOPLEVEL XCHAL_EXCM_LEVEL #define XTENSA_FAKE_NMI (LOCKLEVEL < TOPLEVEL) diff --git a/arch/xtensa/kernel/traps.c b/arch/xtensa/kernel/traps.c index 42d441f7898b..be0cae8082c7 100644 --- a/arch/xtensa/kernel/traps.c +++ b/arch/xtensa/kernel/traps.c @@ -205,6 +205,32 @@ extern void do_IRQ(int, struct pt_regs *); #if XTENSA_FAKE_NMI +#define IS_POW2(v) (((v) & ((v) - 1)) == 0) + +#if !(PROFILING_INTLEVEL == XCHAL_EXCM_LEVEL && \ + IS_POW2(XTENSA_INTLEVEL_MASK(PROFILING_INTLEVEL))) +#warning "Fake NMI is requested for PMM, but there are other IRQs at or above its level." +#warning "Fake NMI will be used, but there will be a bugcheck if one of those IRQs fire." + +static inline void check_valid_nmi(void) +{ + unsigned intread = get_sr(interrupt); + unsigned intenable = get_sr(intenable); + + BUG_ON(intread & intenable & + ~(XTENSA_INTLEVEL_ANDBELOW_MASK(PROFILING_INTLEVEL) ^ + XTENSA_INTLEVEL_MASK(PROFILING_INTLEVEL) ^ + BIT(XCHAL_PROFILING_INTERRUPT))); +} + +#else + +static inline void check_valid_nmi(void) +{ +} + +#endif + irqreturn_t xtensa_pmu_irq_handler(int irq, void *dev_id); DEFINE_PER_CPU(unsigned long, nmi_count); @@ -219,6 +245,7 @@ void do_nmi(struct pt_regs *regs) old_regs = set_irq_regs(regs); nmi_enter(); ++*this_cpu_ptr(&nmi_count); + check_valid_nmi(); xtensa_pmu_irq_handler(0, NULL); nmi_exit(); set_irq_regs(old_regs); |