cpuset/cpuset.c

148 linhas
2.7 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/stat.h>
#define CPUSET(x) "/sys/fs/cgroup/cpuset/"x
#define ACTION_ENABLE 1
#define ACTION_DISABLE 2
char *readLine(FILE *fp, char *buffer) {
int ch;
int i = 0;
size_t buff_len = 0;
buffer = malloc(buff_len + 1);
if(!buffer) {
return NULL;
}
while((ch = fgetc(fp)) != '\n' && ch != EOF) {
buff_len++;
void *tmp = realloc(buffer, buff_len + 1);
if(tmp == NULL) {
free(buffer);
return NULL;
}
buffer = tmp;
buffer[i] = (char) ch;
i++;
}
buffer[i] = '\0';
if(ch == EOF && (i == 0 || ferror(fp))) {
free(buffer);
return NULL;
}
return buffer;
}
int moveTasks(char *src, char *dst) {
FILE *fd1, *fd2;
char *pid;
fd1 = fopen(src, "rb");
if(fd1 == NULL) {
return 255;
}
while((pid = readLine(fd1, 0)) != NULL) {
if(strtol(pid, (char **)NULL, 10) != getppid()) {
fd2 = fopen(dst, "wb");
if(fd2 == NULL) {
return 255;
}
fprintf(fd2, "%s\n", pid);
fclose(fd2);
free(pid);
}
}
fclose(fd1);
return 0;
}
int setGroup(char *dest, char *data) {
FILE *fd;
fd = fopen(dest, "wb");
if(fd == NULL) {
return 255;
}
fprintf(fd, "%s", data);
fclose(fd);
return 0;
}
int disableGroup() {
struct stat sb = {0};
printf("Disabling CGROUPS ... ");
if(stat(CPUSET("host"), &sb) == 0) {
if(moveTasks(CPUSET("host/tasks"), CPUSET("tasks")) != 0) {
return 255;
}
rmdir(CPUSET("host"));
printf("OK!\n");
} else {
printf("SKIPPED!\n");
}
return 0;
}
int enableGroup(char *cpu, char *mem) {
struct stat sb = {0};
printf("Enabling CGROUPS ... ");
if(stat(CPUSET("host"), &sb) == -1) {
mkdir(CPUSET("host"), 0755);
}
if(setGroup(CPUSET("host/cpuset.cpus"), cpu) != 0) {
printf("FAIL!\n");
return 255;
}
if(setGroup(CPUSET("host/cpuset.mems"), mem) != 0) {
printf("FAIL!\n");
return 255;
}
if(moveTasks(CPUSET("tasks"), CPUSET("host/tasks")) != 0) {
printf("FAIL!\n");
return 255;
}
printf("OK!\n");
return 0;
}
int main(int argc, char *argv[]) {
int opt;
int action = 0;
char *cpu = {0};
char *mem = {0};
while((opt = getopt(argc, argv, ":edc:m:")) != -1) {
switch(opt) {
case 'e':
action = ACTION_ENABLE;
break;
case 'd':
action = ACTION_DISABLE;
break;
case 'c':
cpu = optarg;
break;
case 'm':
mem = optarg;
break;
case ':':
printf("Option needs a value!\n");
return 1;
default:
printf("Invalid option: -%c!\n", optopt);
return 1;
}
}
if(action == ACTION_ENABLE) {
if(!cpu || !mem) {
printf("No CPU or memory pinning specified!\n");
return 1;
}
return enableGroup(cpu, mem);
} else if(action == ACTION_DISABLE) {
return disableGroup();
} else {
printf("No action specified!\n");
}
return 0;
}