redis_study/src/setcpuaffinity.c
2020-09-05 12:01:22 +08:00

149 lines
3.8 KiB
C

/* ==========================================================================
* setcpuaffinity.c - Linux/BSD setcpuaffinity.
* --------------------------------------------------------------------------
* Copyright (C) 2020 zhenwei pi
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to permit
* persons to whom the Software is furnished to do so, subject to the
* following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
* NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
* USE OR OTHER DEALINGS IN THE SOFTWARE.
* ==========================================================================
*/
#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#ifdef __linux__
#include <sched.h>
#endif
#ifdef __FreeBSD__
#include <sys/param.h>
#include <sys/cpuset.h>
#endif
#ifdef __NetBSD__
#include <pthread.h>
#include <sched.h>
#endif
#include "config.h"
#ifdef USE_SETCPUAFFINITY
static const char *next_token(const char *q, int sep) {
if (q)
q = strchr(q, sep);
if (q)
q++;
return q;
}
static int next_num(const char *str, char **end, int *result) {
if (!str || *str == '\0' || !isdigit(*str))
return -1;
*result = strtoul(str, end, 10);
if (str == *end)
return -1;
return 0;
}
/* set current thread cpu affinity to cpu list, this function works like
* taskset command (actually cpulist parsing logic reference to util-linux).
* example of this function: "0,2,3", "0,2-3", "0-20:2". */
void setcpuaffinity(const char *cpulist) {
const char *p, *q;
char *end = NULL;
#ifdef __linux__
cpu_set_t cpuset;
#endif
#ifdef __FreeBSD__
cpuset_t cpuset;
#endif
#ifdef __NetBSD__
cpuset_t *cpuset;
#endif
if (!cpulist)
return;
#ifndef __NetBSD__
CPU_ZERO(&cpuset);
#else
cpuset = cpuset_create();
#endif
q = cpulist;
while (p = q, q = next_token(q, ','), p) {
int a, b, s;
const char *c1, *c2;
if (next_num(p, &end, &a) != 0)
return;
b = a;
s = 1;
p = end;
c1 = next_token(p, '-');
c2 = next_token(p, ',');
if (c1 != NULL && (c2 == NULL || c1 < c2)) {
if (next_num(c1, &end, &b) != 0)
return;
c1 = end && *end ? next_token(end, ':') : NULL;
if (c1 != NULL && (c2 == NULL || c1 < c2)) {
if (next_num(c1, &end, &s) != 0)
return;
if (s == 0)
return;
}
}
if ((a > b))
return;
while (a <= b) {
#ifndef __NetBSD__
CPU_SET(a, &cpuset);
#else
cpuset_set(a, cpuset);
#endif
a += s;
}
}
if (end && *end)
return;
#ifdef __linux__
sched_setaffinity(0, sizeof(cpuset), &cpuset);
#endif
#ifdef __FreeBSD__
cpuset_setaffinity(CPU_LEVEL_WHICH, CPU_WHICH_TID, -1, sizeof(cpuset), &cpuset);
#endif
#ifdef __NetBSD__
pthread_setaffinity_np(pthread_self(), cpuset_size(cpuset), cpuset);
cpuset_destroy(cpuset);
#endif
}
#endif /* USE_SETCPUAFFINITY */