diff options
| -rw-r--r-- | tools/testing/selftests/vm/Makefile | 4 | ||||
| -rw-r--r-- | tools/testing/selftests/vm/thuge-gen.c | 254 |
2 files changed, 256 insertions, 2 deletions
diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile index b336b24aa6c..7300d0702ef 100644 --- a/tools/testing/selftests/vm/Makefile +++ b/tools/testing/selftests/vm/Makefile @@ -1,9 +1,9 @@ # Makefile for vm selftests CC = $(CROSS_COMPILE)gcc -CFLAGS = -Wall -Wextra +CFLAGS = -Wall -all: hugepage-mmap hugepage-shm map_hugetlb +all: hugepage-mmap hugepage-shm map_hugetlb thuge-gen %: %.c $(CC) $(CFLAGS) -o $@ $^ diff --git a/tools/testing/selftests/vm/thuge-gen.c b/tools/testing/selftests/vm/thuge-gen.c new file mode 100644 index 00000000000..c87957295f7 --- /dev/null +++ b/tools/testing/selftests/vm/thuge-gen.c @@ -0,0 +1,254 @@ +/* Test selecting other page sizes for mmap/shmget. + + Before running this huge pages for each huge page size must have been + reserved. + For large pages beyond MAX_ORDER (like 1GB on x86) boot options must be used. + Also shmmax must be increased. + And you need to run as root to work around some weird permissions in shm. + And nothing using huge pages should run in parallel. + When the program aborts you may need to clean up the shm segments with + ipcrm -m by hand, like this + sudo ipcs | awk '$1 == "0x00000000" {print $2}' | xargs -n1 sudo ipcrm -m + (warning this will remove all if someone else uses them) */ + +#define _GNU_SOURCE 1 +#include <sys/mman.h> +#include <stdlib.h> +#include <stdio.h> +#include <sys/ipc.h> +#include <sys/shm.h> +#include <sys/stat.h> +#include <glob.h> +#include <assert.h> +#include <unistd.h> +#include <stdarg.h> +#include <string.h> + +#define err(x) perror(x), exit(1) + +#define MAP_HUGE_2MB (21 << MAP_HUGE_SHIFT) +#define MAP_HUGE_1GB (30 << MAP_HUGE_SHIFT) +#define MAP_HUGE_SHIFT 26 +#define MAP_HUGE_MASK 0x3f +#define MAP_HUGETLB 0x40000 + +#define SHM_HUGETLB 04000 /* segment will use huge TLB pages */ +#define SHM_HUGE_SHIFT 26 +#define SHM_HUGE_MASK 0x3f +#define SHM_HUGE_2MB (21 << SHM_HUGE_SHIFT) +#define SHM_HUGE_1GB (30 << SHM_HUGE_SHIFT) + +#define NUM_PAGESIZES 5 + +#define NUM_PAGES 4 + +#define Dprintf(fmt...) // printf(fmt) + +unsigned long page_sizes[NUM_PAGESIZES]; +int num_page_sizes; + +int ilog2(unsigned long v) +{ + int l = 0; + while ((1UL << l) < v) + l++; + return l; +} + +void find_pagesizes(void) +{ + glob_t g; + int i; + glob("/sys/kernel/mm/hugepages/hugepages-*kB", 0, NULL, &g); + assert(g.gl_pathc <= NUM_PAGESIZES); + for (i = 0; i < g.gl_pathc; i++) { + sscanf(g.gl_pathv[i], "/sys/kernel/mm/hugepages/hugepages-%lukB", + &page_sizes[i]); + page_sizes[i] <<= 10; + printf("Found %luMB\n", page_sizes[i] >> 20); + } + num_page_sizes = g.gl_pathc; + globfree(&g); +} + +unsigned long default_huge_page_size(void) +{ + unsigned long hps = 0; + char *line = NULL; + size_t linelen = 0; + FILE *f = fopen("/proc/meminfo", "r"); + if (!f) + return 0; + while (getline(&line, &linelen, f) > 0) { + if (sscanf(line, "Hugepagesize: %lu kB", &hps) == 1) { + hps <<= 10; + break; + } + } + free(line); + return hps; +} + +void show(unsigned long ps) +{ + char buf[100]; + if (ps == getpagesize()) + return; + printf("%luMB: ", ps >> 20); + fflush(stdout); + snprintf(buf, sizeof buf, + "cat /sys/kernel/mm/hugepages/hugepages-%lukB/free_hugepages", + ps >> 10); + system(buf); +} + +unsigned long read_sysfs(int warn, char *fmt, ...) +{ + char *line = NULL; + size_t linelen = 0; + char buf[100]; + FILE *f; + va_list ap; + unsigned long val = 0; + + va_start(ap, fmt); + vsnprintf(buf, sizeof buf, fmt, ap); + va_end(ap); + + f = fopen(buf, "r"); + if (!f) { + if (warn) + printf("missing %s\n", buf); + return 0; + } + if (getline(&line, &linelen, f) > 0) { + sscanf(line, "%lu", &val); + } + fclose(f); + free(line); + return val; +} + +unsigned long read_free(unsigned long ps) +{ + return read_sysfs(ps != getpagesize(), + "/sys/kernel/mm/hugepages/hugepages-%lukB/free_hugepages", + ps >> 10); +} + +void test_mmap(unsigned long size, unsigned flags) +{ + char *map; + unsigned long before, after; + int err; + + before = read_free(size); + map = mmap(NULL, size*NUM_PAGES, PROT_READ|PROT_WRITE, + MAP_PRIVATE|MAP_ANONYMOUS|MAP_HUGETLB|flags, 0, 0); + + if (map == (char *)-1) err("mmap"); + memset(map, 0xff, size*NUM_PAGES); + after = read_free(size); + Dprintf("before %lu after %lu diff %ld size %lu\n", + before, after, before - after, size); + assert(size == getpagesize() || (before - after) == NUM_PAGES); + show(size); + err = munmap(map, size); + assert(!err); +} + +void test_shmget(unsigned long size, unsigned flags) +{ + int id; + unsigned long before, after; + int err; + + before = read_free(size); + id = shmget(IPC_PRIVATE, size * NUM_PAGES, IPC_CREAT|0600|flags); + if (id < 0) err("shmget"); + + struct shm_info i; + if (shmctl(id, SHM_INFO, (void *)&i) < 0) err("shmctl"); + Dprintf("alloc %lu res %lu\n", i.shm_tot, i.shm_rss); + + + Dprintf("id %d\n", id); + char *map = shmat(id, NULL, 0600); + if (map == (char*)-1) err("shmat"); + + shmctl(id, IPC_RMID, NULL); + + memset(map, 0xff, size*NUM_PAGES); + after = read_free(size); + + Dprintf("before %lu after %lu diff %ld size %lu\n", + before, after, before - after, size); + assert(size == getpagesize() || (before - after) == NUM_PAGES); + show(size); + err = shmdt(map); + assert(!err); +} + +void sanity_checks(void) +{ + int i; + unsigned long largest = getpagesize(); + + for (i = 0; i < num_page_sizes; i++) { + if (page_sizes[i] > largest) + largest = page_sizes[i]; + + if (read_free(page_sizes[i]) < NUM_PAGES) { + printf("Not enough huge pages for page size %lu MB, need %u\n", + page_sizes[i] >> 20, + NUM_PAGES); + exit(0); + } + } + + if (read_sysfs(0, "/proc/sys/kernel/shmmax") < NUM_PAGES * largest) { + printf("Please do echo %lu > /proc/sys/kernel/shmmax", largest * NUM_PAGES); + exit(0); + } + +#if defined(__x86_64__) + if (largest != 1U<<30) { + printf("No GB pages available on x86-64\n" + "Please boot with hugepagesz=1G hugepages=%d\n", NUM_PAGES); + exit(0); + } +#endif +} + +int main(void) +{ + int i; + unsigned default_hps = default_huge_page_size(); + + find_pagesizes(); + + sanity_checks(); + + for (i = 0; i < num_page_sizes; i++) { + unsigned long ps = page_sizes[i]; + int arg = ilog2(ps) << MAP_HUGE_SHIFT; + printf("Testing %luMB mmap with shift %x\n", ps >> 20, arg); + test_mmap(ps, MAP_HUGETLB | arg); + } + printf("Testing default huge mmap\n"); + test_mmap(default_hps, SHM_HUGETLB); + + puts("Testing non-huge shmget"); + test_shmget(getpagesize(), 0); + + for (i = 0; i < num_page_sizes; i++) { + unsigned long ps = page_sizes[i]; + int arg = ilog2(ps) << SHM_HUGE_SHIFT; + printf("Testing %luMB shmget with shift %x\n", ps >> 20, arg); + test_shmget(ps, SHM_HUGETLB | arg); + } + puts("default huge shmget"); + test_shmget(default_hps, SHM_HUGETLB); + + return 0; +} |