numam-dpdk/lib/power/power_common.c
Bruce Richardson 99a2dd955f lib: remove librte_ prefix from directory names
There is no reason for the DPDK libraries to all have 'librte_' prefix on
the directory names. This prefix makes the directory names longer and also
makes it awkward to add features referring to individual libraries in the
build - should the lib names be specified with or without the prefix.
Therefore, we can just remove the library prefix and use the library's
unique name as the directory name, i.e. 'eal' rather than 'librte_eal'

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
2021-04-21 14:04:09 +02:00

61 lines
1.4 KiB
C

/* SPDX-License-Identifier: BSD-3-Clause
* Copyright(c) 2020 Intel Corporation
*/
#include <limits.h>
#include <stdio.h>
#include <string.h>
#include "power_common.h"
#define POWER_SYSFILE_SCALING_DRIVER \
"/sys/devices/system/cpu/cpu%u/cpufreq/scaling_driver"
int
cpufreq_check_scaling_driver(const char *driver_name)
{
unsigned int lcore_id = 0; /* always check core 0 */
char fullpath[PATH_MAX];
char readbuf[PATH_MAX];
size_t end_idx;
char *s;
FILE *f;
/*
* Check if scaling driver matches what we expect.
*/
snprintf(fullpath, sizeof(fullpath), POWER_SYSFILE_SCALING_DRIVER,
lcore_id);
f = fopen(fullpath, "r");
/* if there's no driver at all, bail out */
if (f == NULL)
return 0;
s = fgets(readbuf, sizeof(readbuf), f);
/* don't need it any more */
fclose(f);
/* if we can't read it, consider unsupported */
if (s == NULL)
return 0;
/* when read from sysfs, driver name has an extra newline at the end */
end_idx = strnlen(readbuf, sizeof(readbuf));
if (end_idx > 0 && readbuf[end_idx - 1] == '\n') {
end_idx--;
readbuf[end_idx] = '\0';
}
/* does the driver name match? */
if (strncmp(readbuf, driver_name, sizeof(readbuf)) != 0)
return 0;
/*
* We might have a situation where the driver is supported, but we don't
* have permissions to do frequency scaling. This error should not be
* handled here, so consider the system to support scaling for now.
*/
return 1;
}