diff options
| -rw-r--r-- | arch/x86/kernel/cpu/perf_event.c | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c index eed3673a8656..224a84f7080c 100644 --- a/arch/x86/kernel/cpu/perf_event.c +++ b/arch/x86/kernel/cpu/perf_event.c @@ -31,6 +31,7 @@ #include <asm/nmi.h> #include <asm/compat.h> #include <asm/smp.h> +#include <asm/alternative.h> #if 0 #undef wrmsrl @@ -363,12 +364,18 @@ again: return new_raw_count; } -/* using X86_FEATURE_PERFCTR_CORE to later implement ALTERNATIVE() here */ static inline int x86_pmu_addr_offset(int index) { - if (boot_cpu_has(X86_FEATURE_PERFCTR_CORE)) - return index << 1; - return index; + int offset; + + /* offset = X86_FEATURE_PERFCTR_CORE ? index << 1 : index */ + alternative_io(ASM_NOP2, + "shll $1, %%eax", + X86_FEATURE_PERFCTR_CORE, + "=a" (offset), + "a" (index)); + + return offset; } static inline unsigned int x86_pmu_config_addr(int index) |