[kvm-unit-tests Patch v4 08/17] x86: pmu: Use macro to replace hard-coded branches event index

Dapeng Mi
2024-04-19T03:45:57Z

Currently the branches event index is a hard-coded number. User could
add new events and cause the branches event index changes in the future,
but don't notice the hard-coded event index and forget to update the
event index synchronously, then the issue comes.

Thus, replace the hard-coded index to a macro.

Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
---
x86/pmu.c | 19 ++++++++++++++++++-
1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/x86/pmu.c b/x86/pmu.c
index 43ef7ecbcaea..fd1b22104fc4 100644
--- a/x86/pmu.c
+++ b/x86/pmu.c
@@ -49,6 +49,22 @@ struct pmu_event {
{"fixed 2", MSR_CORE_PERF_FIXED_CTR0 + 2, 0.1*N, 30*N}
};

+/*
+ * Events index in intel_gp_events[], ensure consistent with
+ * intel_gp_events[].
+ */
+enum {
+ INTEL_BRANCHES_IDX = 5,
+};
+
+/*
+ * Events index in amd_gp_events[], ensure consistent with
+ * amd_gp_events[].
+ */
+enum {
+ AMD_BRANCHES_IDX = 2,
+};
+
char *buf;

static struct pmu_event *gp_events;
@@ -481,7 +497,8 @@ static void check_emulated_instr(void)
{
uint64_t status, instr_start, brnch_start;
uint64_t gp_counter_width = (1ull << pmu.gp_counter_width) - 1;
- unsigned int branch_idx = pmu.is_intel ? 5 : 2;
+ unsigned int branch_idx = pmu.is_intel ?
+ INTEL_BRANCHES_IDX : AMD_BRANCHES_IDX;
pmu_counter_t brnch_cnt = {
.ctr = MSR_GP_COUNTERx(0),
/* branch instructions */
--
2.34.1