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Diffstat (limited to '')
| -rw-r--r-- | tools/testing/selftests/vm/gup_test.c | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/tools/testing/selftests/vm/gup_test.c b/tools/testing/selftests/vm/gup_test.c new file mode 100644 index 000000000..e43879291 --- /dev/null +++ b/tools/testing/selftests/vm/gup_test.c @@ -0,0 +1,271 @@ +#include <fcntl.h> +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <dirent.h> +#include <sys/ioctl.h> +#include <sys/mman.h> +#include <sys/stat.h> +#include <sys/types.h> +#include <pthread.h> +#include <assert.h> +#include <mm/gup_test.h> +#include "../kselftest.h" + +#include "util.h" + +#define MB (1UL << 20) + +/* Just the flags we need, copied from mm.h: */ +#define FOLL_WRITE 0x01 /* check pte is writable */ +#define FOLL_TOUCH 0x02 /* mark page accessed */ + +#define GUP_TEST_FILE "/sys/kernel/debug/gup_test" + +static unsigned long cmd = GUP_FAST_BENCHMARK; +static int gup_fd, repeats = 1; +static unsigned long size = 128 * MB; +/* Serialize prints */ +static pthread_mutex_t print_mutex = PTHREAD_MUTEX_INITIALIZER; + +static char *cmd_to_str(unsigned long cmd) +{ + switch (cmd) { + case GUP_FAST_BENCHMARK: + return "GUP_FAST_BENCHMARK"; + case PIN_FAST_BENCHMARK: + return "PIN_FAST_BENCHMARK"; + case PIN_LONGTERM_BENCHMARK: + return "PIN_LONGTERM_BENCHMARK"; + case GUP_BASIC_TEST: + return "GUP_BASIC_TEST"; + case PIN_BASIC_TEST: + return "PIN_BASIC_TEST"; + case DUMP_USER_PAGES_TEST: + return "DUMP_USER_PAGES_TEST"; + } + return "Unknown command"; +} + +void *gup_thread(void *data) +{ + struct gup_test gup = *(struct gup_test *)data; + int i; + + /* Only report timing information on the *_BENCHMARK commands: */ + if ((cmd == PIN_FAST_BENCHMARK) || (cmd == GUP_FAST_BENCHMARK) || + (cmd == PIN_LONGTERM_BENCHMARK)) { + for (i = 0; i < repeats; i++) { + gup.size = size; + if (ioctl(gup_fd, cmd, &gup)) + perror("ioctl"), exit(1); + + pthread_mutex_lock(&print_mutex); + printf("%s: Time: get:%lld put:%lld us", + cmd_to_str(cmd), gup.get_delta_usec, + gup.put_delta_usec); + if (gup.size != size) + printf(", truncated (size: %lld)", gup.size); + printf("\n"); + pthread_mutex_unlock(&print_mutex); + } + } else { + gup.size = size; + if (ioctl(gup_fd, cmd, &gup)) { + perror("ioctl"); + exit(1); + } + + pthread_mutex_lock(&print_mutex); + printf("%s: done\n", cmd_to_str(cmd)); + if (gup.size != size) + printf("Truncated (size: %lld)\n", gup.size); + pthread_mutex_unlock(&print_mutex); + } + + return NULL; +} + +int main(int argc, char **argv) +{ + struct gup_test gup = { 0 }; + int filed, i, opt, nr_pages = 1, thp = -1, write = 1, nthreads = 1, ret; + int flags = MAP_PRIVATE, touch = 0; + char *file = "/dev/zero"; + pthread_t *tid; + char *p; + + while ((opt = getopt(argc, argv, "m:r:n:F:f:abcj:tTLUuwWSHpz")) != -1) { + switch (opt) { + case 'a': + cmd = PIN_FAST_BENCHMARK; + break; + case 'b': + cmd = PIN_BASIC_TEST; + break; + case 'L': + cmd = PIN_LONGTERM_BENCHMARK; + break; + case 'c': + cmd = DUMP_USER_PAGES_TEST; + /* + * Dump page 0 (index 1). May be overridden later, by + * user's non-option arguments. + * + * .which_pages is zero-based, so that zero can mean "do + * nothing". + */ + gup.which_pages[0] = 1; + break; + case 'p': + /* works only with DUMP_USER_PAGES_TEST */ + gup.test_flags |= GUP_TEST_FLAG_DUMP_PAGES_USE_PIN; + break; + case 'F': + /* strtol, so you can pass flags in hex form */ + gup.gup_flags = strtol(optarg, 0, 0); + break; + case 'j': + nthreads = atoi(optarg); + break; + case 'm': + size = atoi(optarg) * MB; + break; + case 'r': + repeats = atoi(optarg); + break; + case 'n': + nr_pages = atoi(optarg); + break; + case 't': + thp = 1; + break; + case 'T': + thp = 0; + break; + case 'U': + cmd = GUP_BASIC_TEST; + break; + case 'u': + cmd = GUP_FAST_BENCHMARK; + break; + case 'w': + write = 1; + break; + case 'W': + write = 0; + break; + case 'f': + file = optarg; + break; + case 'S': + flags &= ~MAP_PRIVATE; + flags |= MAP_SHARED; + break; + case 'H': + flags |= (MAP_HUGETLB | MAP_ANONYMOUS); + break; + case 'z': + /* fault pages in gup, do not fault in userland */ + touch = 1; + break; + default: + return -1; + } + } + + if (optind < argc) { + int extra_arg_count = 0; + /* + * For example: + * + * ./gup_test -c 0 1 0x1001 + * + * ...to dump pages 0, 1, and 4097 + */ + + while ((optind < argc) && + (extra_arg_count < GUP_TEST_MAX_PAGES_TO_DUMP)) { + /* + * Do the 1-based indexing here, so that the user can + * use normal 0-based indexing on the command line. + */ + long page_index = strtol(argv[optind], 0, 0) + 1; + + gup.which_pages[extra_arg_count] = page_index; + extra_arg_count++; + optind++; + } + } + + filed = open(file, O_RDWR|O_CREAT); + if (filed < 0) { + perror("open"); + exit(filed); + } + + gup.nr_pages_per_call = nr_pages; + if (write) + gup.gup_flags |= FOLL_WRITE; + + gup_fd = open(GUP_TEST_FILE, O_RDWR); + if (gup_fd == -1) { + switch (errno) { + case EACCES: + if (getuid()) + printf("Please run this test as root\n"); + break; + case ENOENT: + if (opendir("/sys/kernel/debug") == NULL) { + printf("mount debugfs at /sys/kernel/debug\n"); + break; + } + printf("check if CONFIG_GUP_TEST is enabled in kernel config\n"); + break; + default: + perror("failed to open " GUP_TEST_FILE); + break; + } + exit(KSFT_SKIP); + } + + p = mmap(NULL, size, PROT_READ | PROT_WRITE, flags, filed, 0); + if (p == MAP_FAILED) { + perror("mmap"); + exit(1); + } + gup.addr = (unsigned long)p; + + if (thp == 1) + madvise(p, size, MADV_HUGEPAGE); + else if (thp == 0) + madvise(p, size, MADV_NOHUGEPAGE); + + /* + * FOLL_TOUCH, in gup_test, is used as an either/or case: either + * fault pages in from the kernel via FOLL_TOUCH, or fault them + * in here, from user space. This allows comparison of performance + * between those two cases. + */ + if (touch) { + gup.gup_flags |= FOLL_TOUCH; + } else { + for (; (unsigned long)p < gup.addr + size; p += PAGE_SIZE) + p[0] = 0; + } + + tid = malloc(sizeof(pthread_t) * nthreads); + assert(tid); + for (i = 0; i < nthreads; i++) { + ret = pthread_create(&tid[i], NULL, gup_thread, &gup); + assert(ret == 0); + } + for (i = 0; i < nthreads; i++) { + ret = pthread_join(tid[i], NULL); + assert(ret == 0); + } + free(tid); + + return 0; +} |