diff options
Diffstat (limited to 'affinity_tools/affinity_tools.c')
| -rw-r--r-- | affinity_tools/affinity_tools.c | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/affinity_tools/affinity_tools.c b/affinity_tools/affinity_tools.c new file mode 100644 index 0000000..33d88f5 --- /dev/null +++ b/affinity_tools/affinity_tools.c @@ -0,0 +1,219 @@ +/* + * affinity_tools - hog a cpu(s) a change affinity of a task + * + * Created by: Olivier Cozette, November 2012 + * Copyright: (C) 2012 ARM Limited + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <string.h> +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <stdbool.h> +#include <sys/syscall.h> +#include <stdlib.h> // for NULL +#include <sys/types.h> +#include <sys/mman.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <signal.h> +#include <stdbool.h> + +#define CPU_MAX 32 +int hog_cpu_pid_nb; +int hog_cpu_pids[CPU_MAX]; + +void hog_cpu_kill(int sig) +{ + int i; + for (i = 0; i < hog_cpu_pid_nb; i++) + kill(hog_cpu_pids[i], SIGKILL); + exit(0); +} + +bool setaffinity(int cpu, int pid) +{ + int mask = 1 << cpu; + int res; + res = syscall(__NR_sched_setaffinity, pid, sizeof(mask), &mask); + if (res < 0) + return false; + return true; +} + +bool setmyaffinity(int cpu) +{ + return setaffinity(cpu, 0); +} + +void hog_cpu(int nb, int * cpu) +{ + hog_cpu_pid_nb = 0; + signal(SIGUSR1, hog_cpu_kill); + while (nb > 1) + { + nb--; + hog_cpu_pids[hog_cpu_pid_nb] = fork(); + if (hog_cpu_pids[hog_cpu_pid_nb] == 0) + { + printf("#HOG on cpu %d\n", cpu[nb]); + if (!setmyaffinity(cpu[nb])) + exit(1); + while (1) + ; + } + hog_cpu_pid_nb++; + } + nb--; + if (!setmyaffinity(cpu[nb])) + exit(1); + while (1) + ; + +} + +void task_set(int nb, int * cpu, int pid) +{ + int mask = 0; + int res, err; + printf("# Set affinity of pid %d to cpu", pid); + while (nb > 0) + { + nb--; + mask |= (1 << cpu[nb]); + printf(" %d", cpu[nb]); + } + printf("\n"); + res = syscall(__NR_sched_setaffinity, pid, sizeof(mask), &mask); + if (res < 0) + printf("# Can't set affinity of pid %d to %d\n", pid, mask); +} + + +bool read_midr(int cpu, unsigned int * implementer, unsigned int * part) +{ + FILE * fd; + bool all_processor = false; + int current_processor = -1; + char str[256]; + *implementer = 0; + *part = 0; + if (!setmyaffinity(cpu)) + return false; + fd = fopen("/proc/cpuinfo", "r"); + if (fd == NULL) + return false; + while ((*part == 0) || (*implementer == 0)) + { + char * number; + while (fscanf(fd, "%*[\n]") > 0) + ; + if (fscanf(fd, "%[^\n]", str) < 1) + break; + if (strncmp(str, "processor", strlen("processor")) == 0) + { + all_processor = true; + sscanf(strchr(str, ':') + 2, "%d", ¤t_processor); + } + if ((all_processor) && (cpu != current_processor)) + continue; + if ((strstr(str, "CPU part") == NULL) + && (strstr(str, "CPU implementer") == NULL)) + continue; + number = strchr(str, ':') + 1; + if (number == NULL) + continue; + while (*number == ' ') + number++; + if (strstr(str, "CPU part") != NULL) + sscanf(number, "0x%x", part); + else + sscanf(number, "0x%x", implementer); + } + fclose(fd); + if ((*part == 0) || (*implementer == 0)) + return false; + return true; +} + + +int main(int argc, char **argv) +{ + int nb; + int cpu[CPU_MAX]; + int taskset = false; + const char * cpu_list; + printf("%s Created by: Olivier Cozette, November 2012 Copyright: (C) 2012 ARM Limited\n", argv[0]); + if (argc < 2) + { + printf("Usage:\n"); + printf("\t CPU\t\tWill hog the cpu CPU cpu is a comma separated list\n"); + printf("\t -pc CPU PID\tWill set affinity of PID to CPU is a comma separated list\n"); + printf("\t -part CPU,IMPLEMENTER,PART\tWill exit 0 if the CPU is this one or exit 1 otherwise\n"); + printf("Example: \"%s -part 0,0x41,0xc07\" will exit 0 if the CPU 0 is an A7\n", argv[0]); + printf("Example: \"%s -part 0,0x41,0xc0f\" will exit 0 if the CPU 0 is an A15\n", argv[0]); + printf("\t -showpart\tWill display part for all CPU\n"); + printf("Example: \"%s -showpart\" \n0,0x41,0xc0f,1,0x41,0xc0f,2,0x41,0xc07,3,0x41,0xc07,4.0x41,0xc07\n", argv[0]); + printf("Meaning CPU0,1 are A15 and CPU2,3,4 are A7\n"); + return 0; + } + + cpu_list = argv[1]; + if ((strcmp(argv[1], "-part") == 0) && (argc > 2)) + { + unsigned int cpu, part, implementer; + unsigned int real_part, real_implementer; + if (sscanf(argv[2], "%d,0x%x,0x%x", &cpu, &implementer, &part) < 3) + { + printf("The option \"-part\" need to be followed by \"CPU,IMPLEMENTER,PART\" and it was <%s>\n", argv[2]); + printf("where CPU is an integer and where IMPLEMENTER and PART are in the form 0x[0-9]*\n"); + exit(1); + } + if (!read_midr(cpu, &real_implementer, &real_part)) + exit(1); + if ((real_implementer != implementer) || (real_part != part)) + exit(1); + exit(0); + } + if (strcmp(argv[1], "-showpart") == 0) + { + bool first = true; + unsigned int cpu, part, implementer; + for (cpu = 0; cpu < 31; cpu++) + { + if (!read_midr(cpu, &implementer, &part)) + continue; + if (!first) + printf(","); + first = false; + printf("%d,0x%x,0x%x", cpu, implementer, part); + } + printf("\n"); + exit(0); + } + if (strcmp(argv[1], "-pc") == 0) + { + taskset = true; + if (argc < 4) + { + printf("need to specify CPU list and PID\n"); + return 1; + } + cpu_list = argv[2]; + } + nb = sscanf(cpu_list, "%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d", + &cpu[0], &cpu[1], &cpu[2], &cpu[3], &cpu[4], &cpu[5], &cpu[6], &cpu[7], + &cpu[8], &cpu[9], &cpu[10], &cpu[11], &cpu[12], &cpu[13], &cpu[14], &cpu[15]); + + if (taskset) + task_set(nb, cpu, atol(argv[3])); + else + hog_cpu(nb, cpu); + + return 0; +} |