1/*
  2 * Stress test for transparent huge pages, memory compaction and migration.
  3 *
  4 * Authors: Konstantin Khlebnikov <koct9i@gmail.com>
  5 *
  6 * This is free and unencumbered software released into the public domain.
  7 */
  8
  9#include <stdlib.h>
 10#include <stdio.h>
 11#include <stdint.h>
 12#include <err.h>
 13#include <time.h>
 14#include <unistd.h>
 15#include <fcntl.h>
 16#include <string.h>
 17#include <sys/mman.h>
 18#include "vm_util.h"
 19#include "../kselftest.h"
 20
 21int backing_fd = -1;
 22int mmap_flags = MAP_ANONYMOUS | MAP_NORESERVE | MAP_PRIVATE;
 23#define PROT_RW (PROT_READ | PROT_WRITE)
 24
 25int main(int argc, char **argv)
 26{
 27	size_t ram, len;
 28	void *ptr, *p;
 29	struct timespec start, a, b;
 30	int i = 0;
 31	char *name = NULL;
 32	double s;
 33	uint8_t *map;
 34	size_t map_len;
 35	int pagemap_fd;
 36	int duration = 0;
 37
 38	ksft_print_header();
 39
 40	ram = sysconf(_SC_PHYS_PAGES);
 41	if (ram > SIZE_MAX / psize() / 4)
 42		ram = SIZE_MAX / 4;
 43	else
 44		ram *= psize();
 45	len = ram;
 46
 47	while (++i < argc) {
 48		if (!strcmp(argv[i], "-h"))
 49			ksft_exit_fail_msg("usage: %s [-f <filename>] [-d <duration>] [size in MiB]\n",
 50					   argv[0]);
 51		else if (!strcmp(argv[i], "-f"))
 52			name = argv[++i];
 53		else if (!strcmp(argv[i], "-d"))
 54			duration = atoi(argv[++i]);
 55		else
 56			len = atoll(argv[i]) << 20;
 57	}
 58
 59	ksft_set_plan(1);
 60
 61	if (name) {
 62		backing_fd = open(name, O_RDWR);
 63		if (backing_fd == -1)
 64			ksft_exit_fail_msg("open %s\n", name);
 65		mmap_flags = MAP_SHARED;
 66	}
 67
 68	warnx("allocate %zd transhuge pages, using %zd MiB virtual memory"
 69	      " and %zd MiB of ram", len >> HPAGE_SHIFT, len >> 20,
 70	      ram >> (20 + HPAGE_SHIFT - pshift() - 1));
 71
 72	pagemap_fd = open("/proc/self/pagemap", O_RDONLY);
 73	if (pagemap_fd < 0)
 74		ksft_exit_fail_msg("open pagemap\n");
 75
 76	len -= len % HPAGE_SIZE;
 77	ptr = mmap(NULL, len + HPAGE_SIZE, PROT_RW, mmap_flags, backing_fd, 0);
 78	if (ptr == MAP_FAILED)
 79		ksft_exit_fail_msg("initial mmap");
 80	ptr += HPAGE_SIZE - (uintptr_t)ptr % HPAGE_SIZE;
 81
 82	if (madvise(ptr, len, MADV_HUGEPAGE))
 83		ksft_exit_fail_msg("MADV_HUGEPAGE");
 84
 85	map_len = ram >> (HPAGE_SHIFT - 1);
 86	map = malloc(map_len);
 87	if (!map)
 88		ksft_exit_fail_msg("map malloc\n");
 89
 90	clock_gettime(CLOCK_MONOTONIC, &start);
 91
 92	while (1) {
 93		int nr_succeed = 0, nr_failed = 0, nr_pages = 0;
 94
 95		memset(map, 0, map_len);
 96
 97		clock_gettime(CLOCK_MONOTONIC, &a);
 98		for (p = ptr; p < ptr + len; p += HPAGE_SIZE) {
 99			int64_t pfn;
100
101			pfn = allocate_transhuge(p, pagemap_fd);
102
103			if (pfn < 0) {
104				nr_failed++;
105			} else {
106				size_t idx = pfn >> (HPAGE_SHIFT - pshift());
107
108				nr_succeed++;
109				if (idx >= map_len) {
110					map = realloc(map, idx + 1);
111					if (!map)
112						ksft_exit_fail_msg("map realloc\n");
113					memset(map + map_len, 0, idx + 1 - map_len);
114					map_len = idx + 1;
115				}
116				if (!map[idx])
117					nr_pages++;
118				map[idx] = 1;
119			}
120
121			/* split transhuge page, keep last page */
122			if (madvise(p, HPAGE_SIZE - psize(), MADV_DONTNEED))
123				ksft_exit_fail_msg("MADV_DONTNEED");
124		}
125		clock_gettime(CLOCK_MONOTONIC, &b);
126		s = b.tv_sec - a.tv_sec + (b.tv_nsec - a.tv_nsec) / 1000000000.;
127
128		ksft_print_msg("%.3f s/loop, %.3f ms/page, %10.3f MiB/s\t"
129			       "%4d succeed, %4d failed, %4d different pages\n",
130			       s, s * 1000 / (len >> HPAGE_SHIFT), len / s / (1 << 20),
131			       nr_succeed, nr_failed, nr_pages);
132
133		if (duration > 0 && b.tv_sec - start.tv_sec >= duration) {
134			ksft_test_result_pass("Completed\n");
135			ksft_finished();
136		}
137	}
138}