[PATCH 3/3] tools/power turbostat: allow turbostat to work when aperf is not available

[David Arcari <darcari@redhat.com>]

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@redhat.com>
Cc: Len Brown <lenb@kernel.org>
Cc: linux-kernel@vger.kernel.org
---
 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