From 8f61aa325fab3a40b7c847bd35601ad99d7959c9 Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Thu, 25 Apr 2013 19:28:27 +0000 Subject: [PATCH] powerpc/perf: Add support for SIER On power8 we have a new SIER (Sampled Instruction Event Register), which captures information about instructions when we have random sampling enabled. Add support for loading the SIER into pt_regs, overloading regs->dar. Also set the new NO_SIPR flag in regs->result if we don't have SIPR. Update regs_sihv/sipr() to look for SIPR/SIHV in SIER. Signed-off-by: Michael Ellerman Acked-by: Paul Mackerras Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/perf_event_server.h | 1 + arch/powerpc/include/asm/reg.h | 5 +++++ arch/powerpc/perf/core-book3s.c | 19 +++++++++++++++++++ 3 files changed, 25 insertions(+) diff --git a/arch/powerpc/include/asm/perf_event_server.h b/arch/powerpc/include/asm/perf_event_server.h index 7074aeccb9f9..57b42da03b62 100644 --- a/arch/powerpc/include/asm/perf_event_server.h +++ b/arch/powerpc/include/asm/perf_event_server.h @@ -53,6 +53,7 @@ struct power_pmu { #define PPMU_NO_CONT_SAMPLING 0x00000008 /* no continuous sampling */ #define PPMU_SIAR_VALID 0x00000010 /* Processor has SIAR Valid bit */ #define PPMU_HAS_SSLOT 0x00000020 /* Has sampled slot in MMCRA */ +#define PPMU_HAS_SIER 0x00000040 /* Has SIER */ /* * Values for flags to get_alternatives() diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h index 5735ebbd5888..5c6fbe2c5ce6 100644 --- a/arch/powerpc/include/asm/reg.h +++ b/arch/powerpc/include/asm/reg.h @@ -671,6 +671,11 @@ #define SPRN_PMC8 794 #define SPRN_SIAR 780 #define SPRN_SDAR 781 +#define SPRN_SIER 784 +#define SIER_SIPR 0x2000000 /* Sampled MSR_PR */ +#define SIER_SIHV 0x1000000 /* Sampled MSR_HV */ +#define SIER_SIAR_VALID 0x0400000 /* SIAR contents valid */ +#define SIER_SDAR_VALID 0x0200000 /* SDAR contents valid */ #define SPRN_PA6T_MMCR0 795 #define PA6T_MMCR0_EN0 0x0000000000000001UL diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c index 1c13c3d899a6..4ac6e64a52ce 100644 --- a/arch/powerpc/perf/core-book3s.c +++ b/arch/powerpc/perf/core-book3s.c @@ -140,6 +140,9 @@ static bool regs_sihv(struct pt_regs *regs) { unsigned long sihv = MMCRA_SIHV; + if (ppmu->flags & PPMU_HAS_SIER) + return !!(regs->dar & SIER_SIHV); + if (ppmu->flags & PPMU_ALT_SIPR) sihv = POWER6_MMCRA_SIHV; @@ -150,6 +153,9 @@ static bool regs_sipr(struct pt_regs *regs) { unsigned long sipr = MMCRA_SIPR; + if (ppmu->flags & PPMU_HAS_SIER) + return !!(regs->dar & SIER_SIPR); + if (ppmu->flags & PPMU_ALT_SIPR) sipr = POWER6_MMCRA_SIPR; @@ -203,6 +209,7 @@ static inline u32 perf_get_misc_flags(struct pt_regs *regs) /* * Overload regs->dsisr to store MMCRA so we only need to read it once * on each interrupt. + * Overload regs->dar to store SIER if we have it. * Overload regs->result to specify whether we should use the MSR (result * is zero) or the SIAR (result is non zero). */ @@ -218,6 +225,18 @@ static inline void perf_read_regs(struct pt_regs *regs) if (ppmu->flags & PPMU_NO_SIPR) regs->result |= 2; + /* + * On power8 if we're in random sampling mode, the SIER is updated. + * If we're in continuous sampling mode, we don't have SIPR. + */ + if (ppmu->flags & PPMU_HAS_SIER) { + if (marked) + regs->dar = mfspr(SPRN_SIER); + else + regs->result |= 2; + } + + /* * If this isn't a PMU exception (eg a software event) the SIAR is * not valid. Use pt_regs. -- 2.39.2