tools/power turbostat: Avoid probing the same perf counters
For the RAPL package energy status counter, Intel and AMD share the same
perf_subsys and perf_name, but with different MSR addresses.
Both rapl_counter_arch_infos[0] and rapl_counter_arch_infos[1] are
introduced to describe this counter for different Vendors.
As a result, the perf counter is probed twice, and causes a failure in
in get_rapl_counters() because expected_read_size and actual_read_size
don't match.
Fix the problem by skipping the already probed counter.
Note, this is not a perfect fix. For example, if different
vendors/platforms use the same MSR value for different purpose, the code
can be fooled when it probes a rapl_counter_arch_infos[] entry that does
not belong to the running Vendor/Platform.
In a long run, better to put rapl_counter_arch_infos[] into the
platform_features so that this becomes Vendor/Platform specific.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
index 6f91ec3..8deb6a2 100644
--- a/tools/power/x86/turbostat/turbostat.c
+++ b/tools/power/x86/turbostat/turbostat.c
@@ -7991,6 +7991,21 @@ void rapl_perf_init(void)
struct rapl_counter_info_t *rci = &rapl_counter_info_perdomain[next_domain];
+ /*
+ * rapl_counter_arch_infos[] can have multiple entries describing the same
+ * counter, due to the difference from different platforms/Vendors.
+ * E.g. rapl_counter_arch_infos[0] and rapl_counter_arch_infos[1] share the
+ * same perf_subsys and perf_name, but with different MSR address.
+ * rapl_counter_arch_infos[0] is for Intel and rapl_counter_arch_infos[1]
+ * is for AMD.
+ * In this case, it is possible that multiple rapl_counter_arch_infos[]
+ * entries are probed just because their perf/msr is duplicate and valid.
+ *
+ * Thus need a check to avoid re-probe the same counters.
+ */
+ if (rci->source[cai->rci_index] != COUNTER_SOURCE_NONE)
+ break;
+
/* Use perf API for this counter */
if (add_rapl_perf_counter(cpu, rci, cai, &scale, &unit) != -1) {
rci->source[cai->rci_index] = COUNTER_SOURCE_PERF;
