tools/power turbostat: Harden probe_intel_uncore_frequency()

If sysfs directory "intel_uncore_frequency/cluster00/" exists,
then use uncore cluster code (now its own routine).

The previous check for
"intel_uncore_frequency/package_00_die_00/current_freq_khz",
could be unreliable in the face of sparse die id's.

Signed-off-by: Len Brown <[email protected]>

tools/power/x86/turbostat/turbostat.c

@@ -5294,16 +5294,13 @@ static void dump_sysfs_file(char *path)
  fprintf(outf, "%s: %s", strrchr(path, '/') + 1, cpuidle_buf);
 }
 
-static void probe_intel_uncore_frequency(void)
+static void probe_intel_uncore_frequency_legacy(void)
 {
  int i, j;
  char path[256];
 
- if (!genuine_intel)
- return;
-
  if (access("/sys/devices/system/cpu/intel_uncore_frequency/package_00_die_00/current_freq_khz", R_OK))
- goto probe_cluster;
+ return;
 
  BIC_PRESENT(BIC_UNCORE_MHZ);
 
@@ -5335,9 +5332,13 @@ static void probe_intel_uncore_frequency(void)
  fprintf(outf, " %d MHz\n", k / 1000);
  }
  }
- return;
+}
+
+static void probe_intel_uncore_frequency_cluster(void)
+{
+ int i;
+ char path[256];
 
-probe_cluster:
  if (access("/sys/devices/system/cpu/intel_uncore_frequency/uncore00/current_freq_khz", R_OK))
  return;
 
@@ -5351,6 +5352,7 @@ static void probe_intel_uncore_frequency(void)
 
  sprintf(path_base, "/sys/devices/system/cpu/intel_uncore_frequency/uncore%02d", i);
 
+ /* uncore## start at 00 and skip no numbers, so stop upon first missing */
  if (access(path_base, R_OK))
  break;
 
@@ -5382,6 +5384,17 @@ static void probe_intel_uncore_frequency(void)
  }
 }
 
+static void probe_intel_uncore_frequency(void)
+{
+ if (!genuine_intel)
+ return;
+
+ if (access("/sys/devices/system/cpu/intel_uncore_frequency/uncore00", R_OK) == 0)
+ probe_intel_uncore_frequency_cluster();
+ else
+ probe_intel_uncore_frequency_legacy();
+}
+
 static void probe_graphics(void)
 {
  /* Xe graphics sysfs knobs */