From 42ed458aa51337357d7632c64aed4528f923e829 Mon Sep 17 00:00:00 2001 From: Stephane Eranian Date: Thu, 7 Dec 2006 02:14:01 +0100 Subject: [PATCH] [PATCH] i386: i386 add X86_FEATURE_PEBS and detection Here is a patch (used by perfmon2) to detect the presence of the Precise Event Based Sampling (PEBS) feature for i386. The patch also adds the cpu_has_pebs macro. - adds X86_FEATURE_PEBS - adds cpu_has_pebs to test for X86_FEATURE_PEBS Signed-off-by: stephane eranian Signed-off-by: Andi Kleen Cc: Andi Kleen Signed-off-by: Andrew Morton --- arch/i386/kernel/cpu/intel.c | 8 +++++++- include/asm-i386/cpufeature.h | 2 ++ 2 files changed, 9 insertions(+), 1 deletion(-) diff --git a/arch/i386/kernel/cpu/intel.c b/arch/i386/kernel/cpu/intel.c index 94a95aa522..798c2f617e 100644 --- a/arch/i386/kernel/cpu/intel.c +++ b/arch/i386/kernel/cpu/intel.c @@ -195,8 +195,14 @@ static void __cpuinit init_intel(struct cpuinfo_x86 *c) if ((c->x86 == 0xf && c->x86_model >= 0x03) || (c->x86 == 0x6 && c->x86_model >= 0x0e)) set_bit(X86_FEATURE_CONSTANT_TSC, c->x86_capability); -} + if (cpu_has_ds) { + unsigned int l1; + rdmsr(MSR_IA32_MISC_ENABLE, l1, l2); + if (!(l1 & (1<<12))) + set_bit(X86_FEATURE_PEBS, c->x86_capability); + } +} static unsigned int __cpuinit intel_size_cache(struct cpuinfo_x86 * c, unsigned int size) { diff --git a/include/asm-i386/cpufeature.h b/include/asm-i386/cpufeature.h index 69ce35049a..231672558c 100644 --- a/include/asm-i386/cpufeature.h +++ b/include/asm-i386/cpufeature.h @@ -73,6 +73,7 @@ #define X86_FEATURE_UP (3*32+ 9) /* smp kernel running on up */ #define X86_FEATURE_FXSAVE_LEAK (3*32+10) /* FXSAVE leaks FOP/FIP/FOP */ #define X86_FEATURE_ARCH_PERFMON (3*32+11) /* Intel Architectural PerfMon */ +#define X86_FEATURE_PEBS (3*32+12) /* Precise-Event Based Sampling */ /* Intel-defined CPU features, CPUID level 0x00000001 (ecx), word 4 */ #define X86_FEATURE_XMM3 (4*32+ 0) /* Streaming SIMD Extensions-3 */ @@ -135,6 +136,7 @@ #define cpu_has_pmm boot_cpu_has(X86_FEATURE_PMM) #define cpu_has_pmm_enabled boot_cpu_has(X86_FEATURE_PMM_EN) #define cpu_has_ds boot_cpu_has(X86_FEATURE_DS) +#define cpu_has_pebs boot_cpu_has(X86_FEATURE_PEBS) #endif /* __ASM_I386_CPUFEATURE_H */ -- 2.39.5