diff options
| author | Stephane Eranian <eranian@hpl.hp.com> | 2006-12-07 02:14:11 +0100 |
|---|---|---|
| committer | Andi Kleen <andi@basil.nowhere.org> | 2006-12-07 02:14:11 +0100 |
| commit | 538f188e03c821c93b355c9fc346806cdd34e286 (patch) | |
| tree | 4fa4a37d35444a51a30722a2af8f8f57ea11449d | |
| parent | ee58fad51a2a767cb2567706ace967705233d881 (diff) | |
[PATCH] i386: i386 add Intel BTS cpufeature bit and detection (take 2)
Here is a small patch for i386 which adds a cpufeature flag and
detection code for Intel's Branch Trace Store (BTS) feature. This
feature can be found on Intel P4 and Core 2 processors among others.
It can also be used by perfmon.
changelog:
- add CPU_FEATURE_BTS
- add Branch Trace Store detection
signed-off-by: stephane eranian <eranian@hpl.hp.com>
Signed-off-by: Andi Kleen <ak@suse.de>
| -rw-r--r-- | arch/i386/kernel/cpu/intel.c | 2 | ||||
| -rw-r--r-- | include/asm-i386/cpufeature.h | 2 |
2 files changed, 4 insertions, 0 deletions
diff --git a/arch/i386/kernel/cpu/intel.c b/arch/i386/kernel/cpu/intel.c index 3ae795e9056..56fe2658495 100644 --- a/arch/i386/kernel/cpu/intel.c +++ b/arch/i386/kernel/cpu/intel.c @@ -199,6 +199,8 @@ static void __cpuinit init_intel(struct cpuinfo_x86 *c) if (cpu_has_ds) { unsigned int l1; rdmsr(MSR_IA32_MISC_ENABLE, l1, l2); + if (!(l1 & (1<<11))) + set_bit(X86_FEATURE_BTS, c->x86_capability); if (!(l1 & (1<<12))) set_bit(X86_FEATURE_PEBS, c->x86_capability); } diff --git a/include/asm-i386/cpufeature.h b/include/asm-i386/cpufeature.h index 4c83e059228..3f92b94e0d7 100644 --- a/include/asm-i386/cpufeature.h +++ b/include/asm-i386/cpufeature.h @@ -74,6 +74,7 @@ #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 */ +#define X86_FEATURE_BTS (3*32+13) /* Branch Trace Store */ /* Intel-defined CPU features, CPUID level 0x00000001 (ecx), word 4 */ #define X86_FEATURE_XMM3 (4*32+ 0) /* Streaming SIMD Extensions-3 */ @@ -138,6 +139,7 @@ #define cpu_has_ds boot_cpu_has(X86_FEATURE_DS) #define cpu_has_pebs boot_cpu_has(X86_FEATURE_PEBS) #define cpu_has_clflush boot_cpu_has(X86_FEATURE_CLFLSH) +#define cpu_has_bts boot_cpu_has(X86_FEATURE_BTS) #endif /* __ASM_I386_CPUFEATURE_H */ |