[v1.05] Add --measure-max-freq (available on x86 and ARM)

src/arm/midr.c

@@ -15,6 +15,7 @@
 
 #include "../common/global.h"
 #include "../common/soc.h"
+#include "../common/args.h"
 #include "udev.h"
 #include "midr.h"
 #include "uarch.h"
@@ -44,7 +45,8 @@ struct frequency* get_frequency_info(uint32_t core) {
   freq->base = UNKNOWN_DATA;
   freq->max = get_max_freq_from_file(core);
   #ifdef __linux__
-    if (freq->max == UNKNOWN_DATA) {
+    if (freq->max == UNKNOWN_DATA || measure_max_frequency_flag()) {
+      if (freq->max == UNKNOWN_DATA)
         printWarn("Unable to find max frequency from udev, measuring CPU frequency");
       freq->max = measure_max_frequency(core);
       freq->measured = true;

src/common/args.c

@@ -28,6 +28,7 @@ struct args_struct {
   bool help_flag;
   bool raw_flag;
   bool accurate_pp;
+  bool measure_max_frequency_flag;
   bool full_cpu_name_flag;
   bool logo_long;
   bool logo_short;
@@ -50,6 +51,7 @@ const char args_chr[] = {
   /* [ARG_LOGO_INTEL_NEW]   = */ 3,
   /* [ARG_LOGO_INTEL_OLD]   = */ 4,
   /* [ARG_ACCURATE_PP]      = */ 5,
+  /* [ARG_MEASURE_MAX_FREQ] = */ 6,
   /* [ARG_DEBUG]            = */ 'd',
   /* [ARG_VERBOSE]          = */ 'v',
   /* [ARG_VERSION]          = */ 'V',
@@ -66,6 +68,7 @@ const char *args_str[] = {
   /* [ARG_LOGO_INTEL_NEW]   = */ "logo-intel-new",
   /* [ARG_LOGO_INTEL_OLD]   = */ "logo-intel-old",
   /* [ARG_ACCURATE_PP]      = */ "accurate-pp",
+  /* [ARG_MEASURE_MAX_FREQ] = */ "measure-max-freq",
   /* [ARG_DEBUG]            = */ "debug",
   /* [ARG_VERBOSE]          = */ "verbose",
   /* [ARG_VERSION]          = */ "version",
@@ -101,6 +104,10 @@ bool accurate_pp(void) {
   return args.accurate_pp;
 }
 
+bool measure_max_frequency_flag(void) {
+  return args.measure_max_frequency_flag;
+}
+
 bool show_full_cpu_name(void) {
   return args.full_cpu_name_flag;
 }
@@ -222,12 +229,20 @@ char* build_short_options(void) {
   memset(str, 0, sizeof(char) * (len*2 + 1));
 
 #ifdef ARCH_X86
-  sprintf(str, "%c:%c:%c%c%c%c%c%c%c%c%c%c%c",
+  sprintf(str, "%c:%c:%c%c%c%c%c%c%c%c%c%c%c%c",
   c[ARG_STYLE], c[ARG_COLOR], c[ARG_HELP],
   c[ARG_RAW], c[ARG_FULLCPUNAME],
   c[ARG_LOGO_SHORT], c[ARG_LOGO_LONG],
   c[ARG_LOGO_INTEL_NEW], c[ARG_LOGO_INTEL_OLD],
-  c[ARG_ACCURATE_PP], c[ARG_DEBUG], c[ARG_VERBOSE],
+  c[ARG_ACCURATE_PP], c[ARG_MEASURE_MAX_FREQ],
+  c[ARG_DEBUG], c[ARG_VERBOSE],
+  c[ARG_VERSION]);
+#elif ARCH_ARM
+  sprintf(str, "%c:%c:%c%c%c%c%c%c%c",
+  c[ARG_STYLE], c[ARG_COLOR], c[ARG_HELP],
+  c[ARG_LOGO_SHORT], c[ARG_LOGO_LONG],
+  c[ARG_MEASURE_MAX_FREQ],
+  c[ARG_DEBUG], c[ARG_VERBOSE],
   c[ARG_VERSION]);
 #else
   sprintf(str, "%c:%c:%c%c%c%c%c%c",
@@ -270,8 +285,11 @@ bool parse_args(int argc, char* argv[]) {
     {args_str[ARG_LOGO_INTEL_NEW],   no_argument,       0, args_chr[ARG_LOGO_INTEL_NEW]   },
     {args_str[ARG_LOGO_INTEL_OLD],   no_argument,       0, args_chr[ARG_LOGO_INTEL_OLD]   },
     {args_str[ARG_ACCURATE_PP],      no_argument,       0, args_chr[ARG_ACCURATE_PP]      },
+    {args_str[ARG_MEASURE_MAX_FREQ], no_argument,       0, args_chr[ARG_MEASURE_MAX_FREQ] },
     {args_str[ARG_FULLCPUNAME],      no_argument,       0, args_chr[ARG_FULLCPUNAME]      },
     {args_str[ARG_RAW],              no_argument,       0, args_chr[ARG_RAW]              },
+#elif ARCH_ARM
+    {args_str[ARG_MEASURE_MAX_FREQ], no_argument,       0, args_chr[ARG_MEASURE_MAX_FREQ] },
 #endif
     {args_str[ARG_LOGO_SHORT],       no_argument,       0, args_chr[ARG_LOGO_SHORT]       },
     {args_str[ARG_LOGO_LONG],        no_argument,       0, args_chr[ARG_LOGO_LONG]        },
@@ -313,6 +331,9 @@ bool parse_args(int argc, char* argv[]) {
     else if(opt == args_chr[ARG_ACCURATE_PP]) {
        args.accurate_pp = true;
     }
+    else if(opt == args_chr[ARG_MEASURE_MAX_FREQ]) {
+       args.measure_max_frequency_flag = true;
+    }
     else if(opt == args_chr[ARG_FULLCPUNAME]) {
        args.full_cpu_name_flag = true;
     }

src/common/args.h

@@ -29,6 +29,7 @@ enum {
   ARG_LOGO_INTEL_NEW,
   ARG_LOGO_INTEL_OLD,
   ARG_ACCURATE_PP,
+  ARG_MEASURE_MAX_FREQ,
   ARG_DEBUG,
   ARG_VERBOSE,
   ARG_VERSION
@@ -43,6 +44,7 @@ int max_arg_str_length(void);
 bool parse_args(int argc, char* argv[]);
 bool show_help(void);
 bool accurate_pp(void);
+bool measure_max_frequency_flag(void);
 bool show_full_cpu_name(void);
 bool show_logo_long(void);
 bool show_logo_short(void);

src/common/main.c

@@ -30,11 +30,17 @@ void print_help(char *argv[]) {
 #ifdef ARCH_X86
 #ifdef __linux__
   printf("      --%s %*s Compute the peak performance accurately (measure the CPU frequency instead of using the maximum)\n", t[ARG_ACCURATE_PP], (int) (max_len-strlen(t[ARG_ACCURATE_PP])), "");
-#endif
+  printf("      --%s %*s Measure the max CPU frequency instead of reading it\n", t[ARG_MEASURE_MAX_FREQ], (int) (max_len-strlen(t[ARG_MEASURE_MAX_FREQ])), "");
+#endif // __linux__
   printf("      --%s %*s Show the old Intel logo\n", t[ARG_LOGO_INTEL_OLD], (int) (max_len-strlen(t[ARG_LOGO_INTEL_OLD])), "");
   printf("      --%s %*s Show the new Intel logo\n", t[ARG_LOGO_INTEL_NEW], (int) (max_len-strlen(t[ARG_LOGO_INTEL_NEW])), "");
   printf("  -%c, --%s %*s Show the full CPU name (do not abbreviate it)\n", c[ARG_FULLCPUNAME], t[ARG_FULLCPUNAME], (int) (max_len-strlen(t[ARG_FULLCPUNAME])), "");
   printf("  -%c, --%s %*s Print raw cpuid data (debug purposes)\n", c[ARG_RAW], t[ARG_RAW], (int) (max_len-strlen(t[ARG_RAW])), "");
+#endif // ARCH_X86
+#ifdef ARCH_ARM
+#ifdef __linux__
+  printf("      --%s %*s Measure the max CPU frequency instead of reading it\n", t[ARG_MEASURE_MAX_FREQ], (int) (max_len-strlen(t[ARG_MEASURE_MAX_FREQ])), "");
+#endif
 #endif
   printf("  -%c, --%s %*s Print this help and exit\n", c[ARG_HELP], t[ARG_HELP], (int) (max_len-strlen(t[ARG_HELP])), "");
   printf("  -%c, --%s %*s Print cpufetch version and exit\n", c[ARG_VERSION], t[ARG_VERSION], (int) (max_len-strlen(t[ARG_VERSION])), "");
@@ -80,6 +86,11 @@ void print_help(char *argv[]) {
   printf("    --accurate-pp option, which will measure the AVX frequency and show a more precise estimation\n");
   printf("    (this option is only available in x86 architectures).\n");
   printf("    To precisely measure peak performance, see: https://github.com/Dr-Noob/peakperf\n");
+  printf("\n");
+  printf("    Both --accurate-pp and --measure-max-freq measure the actual frequency of the CPU. However,\n");
+  printf("    they differ slightly. The former measures the max frequency while running vectorized SSE/AVX\n");
+  printf("    instructions and it is thus x86 only, whereas the latter simply measures the max clock cycle\n");
+  printf("    and is architecture independent.\n");
 }
 
 int main(int argc, char* argv[]) {

src/x86/cpuid.c

@@ -973,7 +973,8 @@ struct frequency* get_frequency_info(struct cpuInfo* cpu) {
   }
 
   #ifdef __linux__
-    if (freq->max == UNKNOWN_DATA) {
+    if (freq->max == UNKNOWN_DATA || measure_max_frequency_flag()) {
+      if (freq->max == UNKNOWN_DATA)
         printWarn("All previous methods failed, measuring CPU frequency");
       // TODO: Support hybrid architectures
       freq->max = measure_max_frequency(0);