diff options
Diffstat (limited to 'tools/testing/selftests/mm/vm_util.c')
-rw-r--r-- | tools/testing/selftests/mm/vm_util.c | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/tools/testing/selftests/mm/vm_util.c b/tools/testing/selftests/mm/vm_util.c new file mode 100644 index 0000000000..558c9cd890 --- /dev/null +++ b/tools/testing/selftests/mm/vm_util.c @@ -0,0 +1,271 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <string.h> +#include <fcntl.h> +#include <dirent.h> +#include <sys/ioctl.h> +#include <linux/userfaultfd.h> +#include <sys/syscall.h> +#include <unistd.h> +#include "../kselftest.h" +#include "vm_util.h" + +#define PMD_SIZE_FILE_PATH "/sys/kernel/mm/transparent_hugepage/hpage_pmd_size" +#define SMAP_FILE_PATH "/proc/self/smaps" +#define MAX_LINE_LENGTH 500 + +unsigned int __page_size; +unsigned int __page_shift; + +uint64_t pagemap_get_entry(int fd, char *start) +{ + const unsigned long pfn = (unsigned long)start / getpagesize(); + uint64_t entry; + int ret; + + ret = pread(fd, &entry, sizeof(entry), pfn * sizeof(entry)); + if (ret != sizeof(entry)) + ksft_exit_fail_msg("reading pagemap failed\n"); + return entry; +} + +bool pagemap_is_softdirty(int fd, char *start) +{ + return pagemap_get_entry(fd, start) & PM_SOFT_DIRTY; +} + +bool pagemap_is_swapped(int fd, char *start) +{ + return pagemap_get_entry(fd, start) & PM_SWAP; +} + +bool pagemap_is_populated(int fd, char *start) +{ + return pagemap_get_entry(fd, start) & (PM_PRESENT | PM_SWAP); +} + +unsigned long pagemap_get_pfn(int fd, char *start) +{ + uint64_t entry = pagemap_get_entry(fd, start); + + /* If present (63th bit), PFN is at bit 0 -- 54. */ + if (entry & PM_PRESENT) + return entry & 0x007fffffffffffffull; + return -1ul; +} + +void clear_softdirty(void) +{ + int ret; + const char *ctrl = "4"; + int fd = open("/proc/self/clear_refs", O_WRONLY); + + if (fd < 0) + ksft_exit_fail_msg("opening clear_refs failed\n"); + ret = write(fd, ctrl, strlen(ctrl)); + close(fd); + if (ret != strlen(ctrl)) + ksft_exit_fail_msg("writing clear_refs failed\n"); +} + +bool check_for_pattern(FILE *fp, const char *pattern, char *buf, size_t len) +{ + while (fgets(buf, len, fp)) { + if (!strncmp(buf, pattern, strlen(pattern))) + return true; + } + return false; +} + +uint64_t read_pmd_pagesize(void) +{ + int fd; + char buf[20]; + ssize_t num_read; + + fd = open(PMD_SIZE_FILE_PATH, O_RDONLY); + if (fd == -1) + return 0; + + num_read = read(fd, buf, 19); + if (num_read < 1) { + close(fd); + return 0; + } + buf[num_read] = '\0'; + close(fd); + + return strtoul(buf, NULL, 10); +} + +bool __check_huge(void *addr, char *pattern, int nr_hpages, + uint64_t hpage_size) +{ + uint64_t thp = -1; + int ret; + FILE *fp; + char buffer[MAX_LINE_LENGTH]; + char addr_pattern[MAX_LINE_LENGTH]; + + ret = snprintf(addr_pattern, MAX_LINE_LENGTH, "%08lx-", + (unsigned long) addr); + if (ret >= MAX_LINE_LENGTH) + ksft_exit_fail_msg("%s: Pattern is too long\n", __func__); + + fp = fopen(SMAP_FILE_PATH, "r"); + if (!fp) + ksft_exit_fail_msg("%s: Failed to open file %s\n", __func__, SMAP_FILE_PATH); + + if (!check_for_pattern(fp, addr_pattern, buffer, sizeof(buffer))) + goto err_out; + + /* + * Fetch the pattern in the same block and check the number of + * hugepages. + */ + if (!check_for_pattern(fp, pattern, buffer, sizeof(buffer))) + goto err_out; + + snprintf(addr_pattern, MAX_LINE_LENGTH, "%s%%9ld kB", pattern); + + if (sscanf(buffer, addr_pattern, &thp) != 1) + ksft_exit_fail_msg("Reading smap error\n"); + +err_out: + fclose(fp); + return thp == (nr_hpages * (hpage_size >> 10)); +} + +bool check_huge_anon(void *addr, int nr_hpages, uint64_t hpage_size) +{ + return __check_huge(addr, "AnonHugePages: ", nr_hpages, hpage_size); +} + +bool check_huge_file(void *addr, int nr_hpages, uint64_t hpage_size) +{ + return __check_huge(addr, "FilePmdMapped:", nr_hpages, hpage_size); +} + +bool check_huge_shmem(void *addr, int nr_hpages, uint64_t hpage_size) +{ + return __check_huge(addr, "ShmemPmdMapped:", nr_hpages, hpage_size); +} + +int64_t allocate_transhuge(void *ptr, int pagemap_fd) +{ + uint64_t ent[2]; + + /* drop pmd */ + if (mmap(ptr, HPAGE_SIZE, PROT_READ | PROT_WRITE, + MAP_FIXED | MAP_ANONYMOUS | + MAP_NORESERVE | MAP_PRIVATE, -1, 0) != ptr) + errx(2, "mmap transhuge"); + + if (madvise(ptr, HPAGE_SIZE, MADV_HUGEPAGE)) + err(2, "MADV_HUGEPAGE"); + + /* allocate transparent huge page */ + *(volatile void **)ptr = ptr; + + if (pread(pagemap_fd, ent, sizeof(ent), + (uintptr_t)ptr >> (pshift() - 3)) != sizeof(ent)) + err(2, "read pagemap"); + + if (PAGEMAP_PRESENT(ent[0]) && PAGEMAP_PRESENT(ent[1]) && + PAGEMAP_PFN(ent[0]) + 1 == PAGEMAP_PFN(ent[1]) && + !(PAGEMAP_PFN(ent[0]) & ((1 << (HPAGE_SHIFT - pshift())) - 1))) + return PAGEMAP_PFN(ent[0]); + + return -1; +} + +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); + fclose(f); + return hps; +} + +int detect_hugetlb_page_sizes(size_t sizes[], int max) +{ + DIR *dir = opendir("/sys/kernel/mm/hugepages/"); + int count = 0; + + if (!dir) + return 0; + + while (count < max) { + struct dirent *entry = readdir(dir); + size_t kb; + + if (!entry) + break; + if (entry->d_type != DT_DIR) + continue; + if (sscanf(entry->d_name, "hugepages-%zukB", &kb) != 1) + continue; + sizes[count++] = kb * 1024; + ksft_print_msg("[INFO] detected hugetlb page size: %zu KiB\n", + kb); + } + closedir(dir); + return count; +} + +/* If `ioctls' non-NULL, the allowed ioctls will be returned into the var */ +int uffd_register_with_ioctls(int uffd, void *addr, uint64_t len, + bool miss, bool wp, bool minor, uint64_t *ioctls) +{ + struct uffdio_register uffdio_register = { 0 }; + uint64_t mode = 0; + int ret = 0; + + if (miss) + mode |= UFFDIO_REGISTER_MODE_MISSING; + if (wp) + mode |= UFFDIO_REGISTER_MODE_WP; + if (minor) + mode |= UFFDIO_REGISTER_MODE_MINOR; + + uffdio_register.range.start = (unsigned long)addr; + uffdio_register.range.len = len; + uffdio_register.mode = mode; + + if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register) == -1) + ret = -errno; + else if (ioctls) + *ioctls = uffdio_register.ioctls; + + return ret; +} + +int uffd_register(int uffd, void *addr, uint64_t len, + bool miss, bool wp, bool minor) +{ + return uffd_register_with_ioctls(uffd, addr, len, + miss, wp, minor, NULL); +} + +int uffd_unregister(int uffd, void *addr, uint64_t len) +{ + struct uffdio_range range = { .start = (uintptr_t)addr, .len = len }; + int ret = 0; + + if (ioctl(uffd, UFFDIO_UNREGISTER, &range) == -1) + ret = -errno; + + return ret; +} |