[tip: perf/core] perf/x86: Add a macro for RDPMC offset of fixed counters

[tip-bot2 for Kan Liang]

The following commit has been merged into the perf/core branch of tip:

Commit-ID:     0e2e45e2ded4988f5641115fd996c75dc32e4be3
Gitweb:        https://git.kernel.org/tip/0e2e45e2ded4988f5641115fd996c75dc32e4be3
Author:        Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
AuthorDate:    Thu, 23 Jul 2020 10:11:12 -07:00
Committer:     Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Tue, 18 Aug 2020 16:34:36 +02:00

perf/x86: Add a macro for RDPMC offset of fixed counters

The RDPMC base offset of fixed counters is hard-code. Use a meaningful
name to replace the magic number to improve the readability of the code.

Signed-off-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/20200723171117.9918-10-kan.liang@xxxxxxxxxxxxxxx
---
 arch/x86/events/core.c            | 3 ++-
 arch/x86/include/asm/perf_event.h | 3 +++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index 53fcf0a..ebf723f 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -1151,7 +1151,8 @@ static inline void x86_assign_hw_event(struct perf_event *event,
 		hwc->config_base = MSR_ARCH_PERFMON_FIXED_CTR_CTRL;
 		hwc->event_base = MSR_ARCH_PERFMON_FIXED_CTR0 +
 				(idx - INTEL_PMC_IDX_FIXED);
-		hwc->event_base_rdpmc = (idx - INTEL_PMC_IDX_FIXED) | 1<<30;
+		hwc->event_base_rdpmc = (idx - INTEL_PMC_IDX_FIXED) |
+					INTEL_PMC_FIXED_RDPMC_BASE;
 		break;
 
 	default:
diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h
index 000cab7..964ba31 100644
--- a/arch/x86/include/asm/perf_event.h
+++ b/arch/x86/include/asm/perf_event.h
@@ -196,6 +196,9 @@ struct x86_pmu_capability {
  * Fixed-purpose performance events:
  */
 
+/* RDPMC offset for Fixed PMCs */
+#define INTEL_PMC_FIXED_RDPMC_BASE		(1 << 30)
+
 /*
  * All the fixed-mode PMCs are configured via this single MSR:
  */