[PATCH 3/3] tools/power turbostat: allow turbostat to work when aperf is not available
From: David Arcari
Date: Tue Nov 18 2025 - 11:04:33 EST
Currently when aperf is not available the function has_amperf() still
returns true. The end result is that the program gets an error in
delta_thread() which causes turbostat to restart. We can avoid this
by not setting msr_counter_arch_infos[MSR_ARCH_INFO_APERF_INDEX].present
when aperf is not available allowing turbostat to execute normally.
Signed-off-by: David Arcari <darcari@xxxxxxxxxx>
Cc: Len Brown <lenb@xxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
tools/power/x86/turbostat/turbostat.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
index 5567b9ecd516..b3f1e4ae5813 100644
--- a/tools/power/x86/turbostat/turbostat.c
+++ b/tools/power/x86/turbostat/turbostat.c
@@ -8592,6 +8592,10 @@ void msr_perf_init_(void)
continue;
if (cai->needed) {
+ /* check to see if APERF is available */
+ if (cidx == MSR_ARCH_INFO_APERF_INDEX && !has_aperf)
+ continue;
+
/* Use perf API for this counter */
if (add_msr_perf_counter(cpu, cci, cai) != -1) {
cci->source[cai->rci_index] = COUNTER_SOURCE_PERF;
--
2.51.0