// SPDX-License-Identifier: GPL-2.0-or-later/* * Context switch microbenchmark. * * Copyright (C) 2015 Anton Blanchard <anton@au.ibm.com>, IBM */ #define _GNU_SOURCE#include <errno.h>#include <sched.h>#include <string.h>#include <stdio.h>#include <unistd.h>#include <stdlib.h>#include <getopt.h>#include <signal.h>#include <assert.h>#include <pthread.h>#include <limits.h>#include <sys/time.h>#include <sys/syscall.h>#include <sys/sysinfo.h>#include <sys/types.h>#include <sys/shm.h>#include <linux/futex.h>#ifdef __powerpc__#include <altivec.h>#endif#include "utils.h" static unsigned int timeout = 30; static int touch_vdso;struct timeval tv; static int touch_fp = 1;double fp; static int touch_vector = 1;vector int a, b, c; #ifdef __powerpc__static int touch_altivec = 1; /* * Note: LTO (Link Time Optimisation) doesn't play well with this function * attribute. Be very careful enabling LTO for this test. */static void __attribute__((__target__("no-vsx"))) altivec_touch_fn(void){ c = a + b;}#endif static void touch(void){ if (touch_vdso) gettimeofday(&tv, NULL); if (touch_fp) fp += 0.1; #ifdef __powerpc__ if (touch_altivec) altivec_touch_fn();#endif if (touch_vector) c = a + b; asm volatile("# %0 %1 %2": : "r"(&tv), "r"(&fp), "r"(&c));} static void start_thread_on(void *(*fn)(void *), void *arg, unsigned long cpu){ int rc; pthread_t tid; cpu_set_t cpuset; pthread_attr_t attr; CPU_ZERO(&cpuset); CPU_SET(cpu, &cpuset); rc = pthread_attr_init(&attr); if (rc) { errno = rc; perror("pthread_attr_init"); exit(1); } rc = pthread_attr_setaffinity_np(&attr, sizeof(cpu_set_t), &cpuset); if (rc) { errno = rc; perror("pthread_attr_setaffinity_np"); exit(1); } rc = pthread_create(&tid, &attr, fn, arg); if (rc) { errno = rc; perror("pthread_create"); exit(1); }} static void start_process_on(void *(*fn)(void *), void *arg, unsigned long cpu){ int pid, ncpus; cpu_set_t *cpuset; size_t size; pid = fork(); if (pid == -1) { perror("fork"); exit(1); } if (pid) return; ncpus = get_nprocs(); size = CPU_ALLOC_SIZE(ncpus); cpuset = CPU_ALLOC(ncpus); if (!cpuset) { perror("malloc"); exit(1); } CPU_ZERO_S(size, cpuset); CPU_SET_S(cpu, size, cpuset); if (sched_setaffinity(0, size, cpuset)) { perror("sched_setaffinity"); CPU_FREE(cpuset); exit(1); } CPU_FREE(cpuset); fn(arg); exit(0);} static unsigned long iterations;static unsigned long iterations_prev; static void sigalrm_handler(int junk){ unsigned long i = iterations; printf("%ld\n", i - iterations_prev); iterations_prev = i; if (--timeout == 0) kill(0, SIGUSR1); alarm(1);} static void sigusr1_handler(int junk){ exit(0);} struct actions { void (*setup)(int, int); void *(*thread1)(void *); void *(*thread2)(void *);}; #define READ 0#define WRITE 1 static int pipe_fd1[2];static int pipe_fd2[2]; static void pipe_setup(int cpu1, int cpu2){ if (pipe(pipe_fd1) || pipe(pipe_fd2)) exit(1);} static void *pipe_thread1(void *arg){ signal(SIGALRM, sigalrm_handler); alarm(1); while (1) { assert(read(pipe_fd1[READ], &c, 1) == 1); touch(); assert(write(pipe_fd2[WRITE], &c, 1) == 1); touch(); iterations += 2; } return NULL;} static void *pipe_thread2(void *arg){ while (1) { assert(write(pipe_fd1[WRITE], &c, 1) == 1); touch(); assert(read(pipe_fd2[READ], &c, 1) == 1); touch(); } return NULL;} static struct actions pipe_actions = { .setup = pipe_setup, .thread1 = pipe_thread1, .thread2 = pipe_thread2,}; static void yield_setup(int cpu1, int cpu2){ if (cpu1 != cpu2) { fprintf(stderr, "Both threads must be on the same CPU for yield test\n"); exit(1); }} static void *yield_thread1(void *arg){ signal(SIGALRM, sigalrm_handler); alarm(1); while (1) { sched_yield(); touch(); iterations += 2; } return NULL;} static void *yield_thread2(void *arg){ while (1) { sched_yield(); touch(); } return NULL;} static struct actions yield_actions = { .setup = yield_setup, .thread1 = yield_thread1, .thread2 = yield_thread2,}; static long sys_futex(void *addr1, int op, int val1, struct timespec *timeout, void *addr2, int val3){ return syscall(SYS_futex, addr1, op, val1, timeout, addr2, val3);} static unsigned long cmpxchg(unsigned long *p, unsigned long expected, unsigned long desired){ unsigned long exp = expected; __atomic_compare_exchange_n(p, &exp, desired, 0, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST); return exp;} static unsigned long xchg(unsigned long *p, unsigned long val){ return __atomic_exchange_n(p, val, __ATOMIC_SEQ_CST);} static int processes; static int mutex_lock(unsigned long *m){ int c; int flags = FUTEX_WAIT; if (!processes) flags |= FUTEX_PRIVATE_FLAG; c = cmpxchg(m, 0, 1); if (!c) return 0; if (c == 1) c = xchg(m, 2); while (c) { sys_futex(m, flags, 2, NULL, NULL, 0); c = xchg(m, 2); } return 0;} static int mutex_unlock(unsigned long *m){ int flags = FUTEX_WAKE; if (!processes) flags |= FUTEX_PRIVATE_FLAG; if (*m == 2) *m = 0; else if (xchg(m, 0) == 1) return 0; sys_futex(m, flags, 1, NULL, NULL, 0); return 0;} static unsigned long *m1, *m2; static void futex_setup(int cpu1, int cpu2){ if (!processes) { static unsigned long _m1, _m2; m1 = &_m1; m2 = &_m2; } else { int shmid; void *shmaddr; shmid = shmget(IPC_PRIVATE, getpagesize(), SHM_R | SHM_W); if (shmid < 0) { perror("shmget"); exit(1); } shmaddr = shmat(shmid, NULL, 0); if (shmaddr == (char *)-1) { perror("shmat"); shmctl(shmid, IPC_RMID, NULL); exit(1); } shmctl(shmid, IPC_RMID, NULL); m1 = shmaddr; m2 = shmaddr + sizeof(*m1); } *m1 = 0; *m2 = 0; mutex_lock(m1); mutex_lock(m2);} static void *futex_thread1(void *arg){ signal(SIGALRM, sigalrm_handler); alarm(1); while (1) { mutex_lock(m2); mutex_unlock(m1); iterations += 2; } return NULL;} static void *futex_thread2(void *arg){ while (1) { mutex_unlock(m2); mutex_lock(m1); } return NULL;} static struct actions futex_actions = { .setup = futex_setup, .thread1 = futex_thread1, .thread2 = futex_thread2,}; static struct option options[] = { { "test", required_argument, 0, 't' }, { "process", no_argument, &processes, 1 }, { "timeout", required_argument, 0, 's' }, { "vdso", no_argument, &touch_vdso, 1 }, { "no-fp", no_argument, &touch_fp, 0 },#ifdef __powerpc__ { "no-altivec", no_argument, &touch_altivec, 0 },#endif { "no-vector", no_argument, &touch_vector, 0 }, { 0, },}; static void usage(void){ fprintf(stderr, "Usage: context_switch2 <options> CPU1 CPU2\n\n"); fprintf(stderr, "\t\t--test=X\tpipe, futex or yield (default)\n"); fprintf(stderr, "\t\t--process\tUse processes (default threads)\n"); fprintf(stderr, "\t\t--timeout=X\tDuration in seconds to run (default 30)\n"); fprintf(stderr, "\t\t--vdso\t\ttouch VDSO\n"); fprintf(stderr, "\t\t--no-fp\t\tDon't touch FP\n");#ifdef __powerpc__ fprintf(stderr, "\t\t--no-altivec\tDon't touch altivec\n");#endif fprintf(stderr, "\t\t--no-vector\tDon't touch vector\n");} int main(int argc, char *argv[]){ signed char c; struct actions *actions = &yield_actions; int cpu1; int cpu2; static void (*start_fn)(void *(*fn)(void *), void *arg, unsigned long cpu); while (1) { int option_index = 0; c = getopt_long(argc, argv, "", options, &option_index); if (c == -1) break; switch (c) { case 0: if (options[option_index].flag != 0) break; usage(); exit(1); break; case 't': if (!strcmp(optarg, "pipe")) { actions = &pipe_actions; } else if (!strcmp(optarg, "yield")) { actions = &yield_actions; } else if (!strcmp(optarg, "futex")) { actions = &futex_actions; } else { usage(); exit(1); } break; case 's': timeout = atoi(optarg); break; default: usage(); exit(1); } } if (processes) start_fn = start_process_on; else start_fn = start_thread_on; if (((argc - optind) != 2)) { cpu1 = cpu2 = pick_online_cpu(); } else { cpu1 = atoi(argv[optind++]); cpu2 = atoi(argv[optind++]); } printf("Using %s with ", processes ? "processes" : "threads"); if (actions == &pipe_actions) printf("pipe"); else if (actions == &yield_actions) printf("yield"); else printf("futex"); if (!have_hwcap(PPC_FEATURE_HAS_ALTIVEC)) touch_altivec = 0; if (!have_hwcap(PPC_FEATURE_HAS_VSX)) touch_vector = 0; printf(" on cpus %d/%d touching FP:%s altivec:%s vector:%s vdso:%s\n", cpu1, cpu2, touch_fp ? "yes" : "no", touch_altivec ? "yes" : "no", touch_vector ? "yes" : "no", touch_vdso ? "yes" : "no"); /* Create a new process group so we can signal everyone for exit */ setpgid(getpid(), getpid()); signal(SIGUSR1, sigusr1_handler); actions->setup(cpu1, cpu2); Lines 1–500 of 508. Load more
// SPDX-License-Identifier: GPL-2.0-or-later /* * Context switch microbenchmark. * * Copyright (C) 2015 Anton Blanchard <anton@au.ibm.com>, IBM */ #define _GNU_SOURCE #include <errno.h> #include <sched.h> #include <string.h> #include <stdio.h> #include <unistd.h> #include <stdlib.h> #include <getopt.h> #include <signal.h> #include <assert.h> #include <pthread.h> #include <limits.h> #include <sys/time.h> #include <sys/syscall.h> #include <sys/sysinfo.h> #include <sys/types.h> #include <sys/shm.h> #include <linux/futex.h> #ifdef __powerpc__ #include <altivec.h> #endif #include "utils.h" static unsigned int timeout = 30; static int touch_vdso; struct timeval tv; static int touch_fp = 1; double fp; static int touch_vector = 1; vector int a, b, c; #ifdef __powerpc__ static int touch_altivec = 1; /* * Note: LTO (Link Time Optimisation) doesn't play well with this function * attribute. Be very careful enabling LTO for this test. */ static void __attribute__((__target__("no-vsx"))) altivec_touch_fn(void) { c = a + b; } #endif static void touch(void) { if (touch_vdso) gettimeofday(&tv, NULL); if (touch_fp) fp += 0.1; #ifdef __powerpc__ if (touch_altivec) altivec_touch_fn(); #endif if (touch_vector) c = a + b; asm volatile("# %0 %1 %2": : "r"(&tv), "r"(&fp), "r"(&c)); } static void start_thread_on(void *(*fn)(void *), void *arg, unsigned long cpu) { int rc; pthread_t tid; cpu_set_t cpuset; pthread_attr_t attr; CPU_ZERO(&cpuset); CPU_SET(cpu, &cpuset); rc = pthread_attr_init(&attr); if (rc) { errno = rc; perror("pthread_attr_init"); exit(1); } rc = pthread_attr_setaffinity_np(&attr, sizeof(cpu_set_t), &cpuset); if (rc) { errno = rc; perror("pthread_attr_setaffinity_np"); exit(1); } rc = pthread_create(&tid, &attr, fn, arg); if (rc) { errno = rc; perror("pthread_create"); exit(1); } } static void start_process_on(void *(*fn)(void *), void *arg, unsigned long cpu) { int pid, ncpus; cpu_set_t *cpuset; size_t size; pid = fork(); if (pid == -1) { perror("fork"); exit(1); } if (pid) return; ncpus = get_nprocs(); size = CPU_ALLOC_SIZE(ncpus); cpuset = CPU_ALLOC(ncpus); if (!cpuset) { perror("malloc"); exit(1); } CPU_ZERO_S(size, cpuset); CPU_SET_S(cpu, size, cpuset); if (sched_setaffinity(0, size, cpuset)) { perror("sched_setaffinity"); CPU_FREE(cpuset); exit(1); } CPU_FREE(cpuset); fn(arg); exit(0); } static unsigned long iterations; static unsigned long iterations_prev; static void sigalrm_handler(int junk) { unsigned long i = iterations; printf("%ld\n", i - iterations_prev); iterations_prev = i; if (--timeout == 0) kill(0, SIGUSR1); alarm(1); } static void sigusr1_handler(int junk) { exit(0); } struct actions { void (*setup)(int, int); void *(*thread1)(void *); void *(*thread2)(void *); }; #define READ 0 #define WRITE 1 static int pipe_fd1[2]; static int pipe_fd2[2]; static void pipe_setup(int cpu1, int cpu2) { if (pipe(pipe_fd1) || pipe(pipe_fd2)) exit(1); } static void *pipe_thread1(void *arg) { signal(SIGALRM, sigalrm_handler); alarm(1); while (1) { assert(read(pipe_fd1[READ], &c, 1) == 1); touch(); assert(write(pipe_fd2[WRITE], &c, 1) == 1); touch(); iterations += 2; } return NULL; } static void *pipe_thread2(void *arg) { while (1) { assert(write(pipe_fd1[WRITE], &c, 1) == 1); touch(); assert(read(pipe_fd2[READ], &c, 1) == 1); touch(); } return NULL; } static struct actions pipe_actions = { .setup = pipe_setup, .thread1 = pipe_thread1, .thread2 = pipe_thread2, }; static void yield_setup(int cpu1, int cpu2) { if (cpu1 != cpu2) { fprintf(stderr, "Both threads must be on the same CPU for yield test\n"); exit(1); } } static void *yield_thread1(void *arg) { signal(SIGALRM, sigalrm_handler); alarm(1); while (1) { sched_yield(); touch(); iterations += 2; } return NULL; } static void *yield_thread2(void *arg) { while (1) { sched_yield(); touch(); } return NULL; } static struct actions yield_actions = { .setup = yield_setup, .thread1 = yield_thread1, .thread2 = yield_thread2, }; static long sys_futex(void *addr1, int op, int val1, struct timespec *timeout, void *addr2, int val3) { return syscall(SYS_futex, addr1, op, val1, timeout, addr2, val3); } static unsigned long cmpxchg(unsigned long *p, unsigned long expected, unsigned long desired) { unsigned long exp = expected; __atomic_compare_exchange_n(p, &exp, desired, 0, __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST); return exp; } static unsigned long xchg(unsigned long *p, unsigned long val) { return __atomic_exchange_n(p, val, __ATOMIC_SEQ_CST); } static int processes; static int mutex_lock(unsigned long *m) { int c; int flags = FUTEX_WAIT; if (!processes) flags |= FUTEX_PRIVATE_FLAG; c = cmpxchg(m, 0, 1); if (!c) return 0; if (c == 1) c = xchg(m, 2); while (c) { sys_futex(m, flags, 2, NULL, NULL, 0); c = xchg(m, 2); } return 0; } static int mutex_unlock(unsigned long *m) { int flags = FUTEX_WAKE; if (!processes) flags |= FUTEX_PRIVATE_FLAG; if (*m == 2) *m = 0; else if (xchg(m, 0) == 1) return 0; sys_futex(m, flags, 1, NULL, NULL, 0); return 0; } static unsigned long *m1, *m2; static void futex_setup(int cpu1, int cpu2) { if (!processes) { static unsigned long _m1, _m2; m1 = &_m1; m2 = &_m2; } else { int shmid; void *shmaddr; shmid = shmget(IPC_PRIVATE, getpagesize(), SHM_R | SHM_W); if (shmid < 0) { perror("shmget"); exit(1); } shmaddr = shmat(shmid, NULL, 0); if (shmaddr == (char *)-1) { perror("shmat"); shmctl(shmid, IPC_RMID, NULL); exit(1); } shmctl(shmid, IPC_RMID, NULL); m1 = shmaddr; m2 = shmaddr + sizeof(*m1); } *m1 = 0; *m2 = 0; mutex_lock(m1); mutex_lock(m2); } static void *futex_thread1(void *arg) { signal(SIGALRM, sigalrm_handler); alarm(1); while (1) { mutex_lock(m2); mutex_unlock(m1); iterations += 2; } return NULL; } static void *futex_thread2(void *arg) { while (1) { mutex_unlock(m2); mutex_lock(m1); } return NULL; } static struct actions futex_actions = { .setup = futex_setup, .thread1 = futex_thread1, .thread2 = futex_thread2, }; static struct option options[] = { { "test", required_argument, 0, 't' }, { "process", no_argument, &processes, 1 }, { "timeout", required_argument, 0, 's' }, { "vdso", no_argument, &touch_vdso, 1 }, { "no-fp", no_argument, &touch_fp, 0 }, #ifdef __powerpc__ { "no-altivec", no_argument, &touch_altivec, 0 }, #endif { "no-vector", no_argument, &touch_vector, 0 }, { 0, }, }; static void usage(void) { fprintf(stderr, "Usage: context_switch2 <options> CPU1 CPU2\n\n"); fprintf(stderr, "\t\t--test=X\tpipe, futex or yield (default)\n"); fprintf(stderr, "\t\t--process\tUse processes (default threads)\n"); fprintf(stderr, "\t\t--timeout=X\tDuration in seconds to run (default 30)\n"); fprintf(stderr, "\t\t--vdso\t\ttouch VDSO\n"); fprintf(stderr, "\t\t--no-fp\t\tDon't touch FP\n"); #ifdef __powerpc__ fprintf(stderr, "\t\t--no-altivec\tDon't touch altivec\n"); #endif fprintf(stderr, "\t\t--no-vector\tDon't touch vector\n"); } int main(int argc, char *argv[]) { signed char c; struct actions *actions = &yield_actions; int cpu1; int cpu2; static void (*start_fn)(void *(*fn)(void *), void *arg, unsigned long cpu); while (1) { int option_index = 0; c = getopt_long(argc, argv, "", options, &option_index); if (c == -1) break; switch (c) { case 0: if (options[option_index].flag != 0) break; usage(); exit(1); break; case 't': if (!strcmp(optarg, "pipe")) { actions = &pipe_actions; } else if (!strcmp(optarg, "yield")) { actions = &yield_actions; } else if (!strcmp(optarg, "futex")) { actions = &futex_actions; } else { usage(); exit(1); } break; case 's': timeout = atoi(optarg); break; default: usage(); exit(1); } } if (processes) start_fn = start_process_on; else start_fn = start_thread_on; if (((argc - optind) != 2)) { cpu1 = cpu2 = pick_online_cpu(); } else { cpu1 = atoi(argv[optind++]); cpu2 = atoi(argv[optind++]); } printf("Using %s with ", processes ? "processes" : "threads"); if (actions == &pipe_actions) printf("pipe"); else if (actions == &yield_actions) printf("yield"); else printf("futex"); if (!have_hwcap(PPC_FEATURE_HAS_ALTIVEC)) touch_altivec = 0; if (!have_hwcap(PPC_FEATURE_HAS_VSX)) touch_vector = 0; printf(" on cpus %d/%d touching FP:%s altivec:%s vector:%s vdso:%s\n", cpu1, cpu2, touch_fp ? "yes" : "no", touch_altivec ? "yes" : "no", touch_vector ? "yes" : "no", touch_vdso ? "yes" : "no"); /* Create a new process group so we can signal everyone for exit */ setpgid(getpid(), getpid()); signal(SIGUSR1, sigusr1_handler); actions->setup(cpu1, cpu2);