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#include "getfreq.h"
#include "getcore.h"
#include "common.h"
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define MAX_CORES 1000
#define MAX_FREQS 50
#define FREQ_LENGTH 14
static char freqs[MAX_CORES][MAX_FREQS][FREQ_LENGTH];
static int total_freqs; /* Number of freqs for core 0 */
/***********************************************************************
* Initialise surrounding variables, get available freqs etc
**********************************************************************/
void gf_init()
{
char freq_string[4096]; /* POSIX suggested line length. Source of error for CPUs with a huge number of freqs */
char *next_token = NULL;
unsigned int i = 0;
memset(freqs, '\0', sizeof(freqs));
for (i = 0; i < gc_number() && i < MAX_CORES; i++)
{
memset(freq_string, '\0', sizeof(freq_string) );
/* Get available governor freqs. If no governor, try next cpu */
if (gf_available(i, freq_string, sizeof(freq_string) ) == -1)
continue;
*strchrnul(freq_string, '\n') = '\0';
/* freq_string is a space separated list of freqs.
* Use strtok to find each */
next_token = strtok(freq_string, " \n");
total_freqs = 0;
do
{
strncpy(freqs[i][total_freqs], next_token, FREQ_LENGTH);
total_freqs++;
} while ((next_token = strtok(NULL, " ")) != NULL);
}
/* Hit the limit of storage of cores' frequencies */
if (i == MAX_CORES)
info("Unable to add more than %d cores\n", MAX_CORES);
}
/***********************************************************************
* Return current frequency for core
**********************************************************************/
int gf_current(int core)
{
FILE* fd = NULL;
char buff[4096];
char path[1024];
int freq = 0;
snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_cur_freq", core);
if (!(fd = fopen(path, "r")))
return -1;
fgets(buff, 13, fd); /* FIXME magic */
freq = atoi(buff);
fclose(fd);
return freq;
}
/***********************************************************************
* Populate `out` with available frequencies for core
**********************************************************************/
int gf_available(int core, char* out, int size)
{
FILE* fd = NULL;
char path[1024];
snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_available_frequencies", core);
if (!(fd = fopen(path, "r")))
return -1;
fgets(out, size, fd);
fclose(fd);
return 0;
}
/***********************************************************************
* Populate `out` with a formatted, units-added freq label for `freq`
**********************************************************************/
void gf_get_frequency_label(char *buffer, size_t max_size, int freq)
{
if (freq >= 1000000000) /* This, ladies and gentlement, is future-proofing */
snprintf(buffer, max_size, "%.2f THz", (double)freq/1000000000 );
else if (freq >= 1000000)
snprintf(buffer, max_size, "%.2f GHz", (double)freq/1000000 );
else if (freq >= 1000)
snprintf(buffer, max_size, "%.2f MHz", (double)freq/1000 );
else
snprintf(buffer, max_size, "%.2f KHz", (double)freq);
}
/***********************************************************************
* Return freq value at index for core, as a string
**********************************************************************/
char* gf_freqa(int core, int index)
{
return freqs[core][index];
}
/***********************************************************************
* Return freq value at index for core, as an int
**********************************************************************/
int gf_freqi(int core, int index)
{
return atoi(gf_freqa(core, index));
}
/***********************************************************************
* Return total number of frequencies
**********************************************************************/
unsigned int gf_number()
{
return total_freqs;
}
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