summaryrefslogtreecommitdiffstats
path: root/tools/testing/selftests/vm/gup_test.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--tools/testing/selftests/vm/gup_test.c271
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;
+}