[v1.03][PPC] Read frequency from cpuinfo if the default method fails

src/ppc/ppc.c

@@ -146,6 +146,12 @@ struct frequency* get_frequency_info(void) {
   freq->max = get_max_freq_from_file(0);
   freq->base = get_min_freq_from_file(0);
 
+  if(freq->max == UNKNOWN_DATA) {
+    // If we are unable to find it in the
+    // standard path, try /proc/cpuinfo
+    freq->max = get_frequency_from_cpuinfo();
+  }
+
   return freq;
 }
 

src/ppc/udev.c

@@ -6,6 +6,7 @@
 
 #define _PATH_TOPO_CORE_ID         "topology/core_id"
 #define _PATH_TOPO_PACKAGE_ID      "topology/physical_package_id"
+#define CPUINFO_FREQUENCY_STR      "clock\t\t: "
 
 bool fill_array_from_sys(int *core_ids, int total_cores, char* SYS_PATH) {
   int filelen;
@@ -57,3 +58,33 @@ bool fill_package_ids_from_sys(int* package_ids, int total_cores) {
   }
   return false;
 }
+
+long get_frequency_from_cpuinfo(void) {
+  char* freq_str = get_field_from_cpuinfo(CPUINFO_FREQUENCY_STR);
+  if(freq_str == NULL) {
+    return UNKNOWN_DATA;
+  }
+  else {
+    // freq_str should be in the form XXXX.YYYYYYMHz
+    char* dot = strstr(freq_str, ".");
+    freq_str[dot-freq_str] = '\0';
+
+    char* end;
+    errno = 0;
+    long ret = strtol(freq_str, &end, 10);
+    if(errno != 0) {
+      printBug("strtol: %s", strerror(errno));
+      free(freq_str);
+      return UNKNOWN_DATA;
+    }
+
+    // We consider it an error if frequency is
+    // greater than 10 GHz or less than 100 MHz
+    if(ret > 10000 || ret <  100) {
+      printBug("Invalid data was read from file '%s': %ld\n", CPUINFO_FREQUENCY_STR, ret);
+      return UNKNOWN_DATA;
+    }
+
+    return ret;
+  }
+}

src/ppc/udev.h

@@ -11,5 +11,6 @@
 bool fill_core_ids_from_sys(int *core_ids, int total_cores);
 bool fill_package_ids_from_sys(int* package_ids, int total_cores);
 int get_num_sockets_package_cpus(struct topology* topo);
+long get_frequency_from_cpuinfo(void);
 
 #endif