| Message ID | 20240730125346.1580150-6-usamaarif642@gmail.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm: split underutilized THPs | expand |
On Tue, 2024-07-30 at 13:46 +0100, Usama Arif wrote: > From: Alexander Zhu <alexlzhu@fb.com> > > Self tests to verify the RssAnon value to make sure zero > pages are not remapped except in the case of userfaultfd. > Also includes a self test for the userfaultfd use case. > > Signed-off-by: Alexander Zhu <alexlzhu@fb.com> > Signed-off-by: Usama Arif <usamaarif642@gmail.com> Acked-by: Rik van Riel <riel@surriel.com>
Hi Usama,
kernel test robot noticed the following build warnings:
[auto build test WARNING on akpm-mm/mm-everything]
url: https://github.com/intel-lab-lkp/linux/commits/Usama-Arif/Revert-memcg-remove-mem_cgroup_uncharge_list/20240730-223949
base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link: https://lore.kernel.org/r/20240730125346.1580150-6-usamaarif642%40gmail.com
patch subject: [PATCH 5/6] mm: add selftests to split_huge_page() to verify unmap/zap of zero pages
:::::: branch date: 32 hours ago
:::::: commit date: 32 hours ago
compiler: gcc-13 (Ubuntu 13.2.0-4ubuntu3) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240801/202408010618.lgnamdZd-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/r/202408010618.lgnamdZd-lkp@intel.com/
All warnings (new ones prefixed by >>):
vm_util.c: In function 'rss_anon':
>> vm_util.c:188:41: warning: format '%ld' expects argument of type 'long int *', but argument 3 has type 'uint64_t *' {aka 'long long unsigned int *'} [-Wformat=]
188 | if (sscanf(buffer, "RssAnon:%10ld kB", &rss_anon) != 1)
| ~~~~^ ~~~~~~~~~
| | |
| | uint64_t * {aka long long unsigned int *}
| long int *
| %10lld
vim +188 tools/testing/selftests/mm/vm_util.c
642bc52aed9c99 tools/testing/selftests/vm/vm_util.c Muhammad Usama Anjum 2022-04-28 174
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 175 uint64_t rss_anon(void)
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 176 {
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 177 uint64_t rss_anon = 0;
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 178 FILE *fp;
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 179 char buffer[MAX_LINE_LENGTH];
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 180
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 181 fp = fopen(STATUS_FILE_PATH, "r");
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 182 if (!fp)
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 183 ksft_exit_fail_msg("%s: Failed to open file %s\n", __func__, STATUS_FILE_PATH);
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 184
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 185 if (!check_for_pattern(fp, "RssAnon:", buffer, sizeof(buffer)))
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 186 goto err_out;
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 187
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 @188 if (sscanf(buffer, "RssAnon:%10ld kB", &rss_anon) != 1)
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 189 ksft_exit_fail_msg("Reading status error\n");
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 190
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 191 err_out:
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 192 fclose(fp);
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 193 return rss_anon;
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 194 }
15bd39f288be91 tools/testing/selftests/mm/vm_util.c Alexander Zhu 2024-07-30 195
diff --git a/tools/testing/selftests/mm/split_huge_page_test.c b/tools/testing/selftests/mm/split_huge_page_test.c index e5e8dafc9d94..da271ad6ff11 100644 --- a/tools/testing/selftests/mm/split_huge_page_test.c +++ b/tools/testing/selftests/mm/split_huge_page_test.c @@ -17,6 +17,8 @@ #include <malloc.h> #include <stdbool.h> #include <time.h> +#include <sys/syscall.h> +#include <linux/userfaultfd.h> #include "vm_util.h" #include "../kselftest.h" @@ -84,6 +86,115 @@ static void write_debugfs(const char *fmt, ...) write_file(SPLIT_DEBUGFS, input, ret + 1); } +static char *allocate_zero_filled_hugepage(size_t len) +{ + char *result; + size_t i; + + result = memalign(pmd_pagesize, len); + if (!result) { + printf("Fail to allocate memory\n"); + exit(EXIT_FAILURE); + } + + madvise(result, len, MADV_HUGEPAGE); + + for (i = 0; i < len; i++) + result[i] = (char)0; + + return result; +} + +static void verify_rss_anon_split_huge_page_all_zeroes(char *one_page, int nr_hpages, size_t len) +{ + uint64_t rss_anon_before, rss_anon_after; + size_t i; + + if (!check_huge_anon(one_page, 4, pmd_pagesize)) { + printf("No THP is allocated\n"); + exit(EXIT_FAILURE); + } + + rss_anon_before = rss_anon(); + if (!rss_anon_before) { + printf("No RssAnon is allocated before split\n"); + exit(EXIT_FAILURE); + } + + /* split all THPs */ + write_debugfs(PID_FMT, getpid(), (uint64_t)one_page, + (uint64_t)one_page + len, 0); + + for (i = 0; i < len; i++) + if (one_page[i] != (char)0) { + printf("%ld byte corrupted\n", i); + exit(EXIT_FAILURE); + } + + if (!check_huge_anon(one_page, 0, pmd_pagesize)) { + printf("Still AnonHugePages not split\n"); + exit(EXIT_FAILURE); + } + + rss_anon_after = rss_anon(); + if (rss_anon_after >= rss_anon_before) { + printf("Incorrect RssAnon value. Before: %ld After: %ld\n", + rss_anon_before, rss_anon_after); + exit(EXIT_FAILURE); + } +} + +void split_pmd_zero_pages(void) +{ + char *one_page; + int nr_hpages = 4; + size_t len = nr_hpages * pmd_pagesize; + + one_page = allocate_zero_filled_hugepage(len); + verify_rss_anon_split_huge_page_all_zeroes(one_page, nr_hpages, len); + printf("Split zero filled huge pages successful\n"); + free(one_page); +} + +void split_pmd_zero_pages_uffd(void) +{ + char *one_page; + int nr_hpages = 4; + size_t len = nr_hpages * pmd_pagesize; + long uffd; /* userfaultfd file descriptor */ + struct uffdio_api uffdio_api; + struct uffdio_register uffdio_register; + + /* Create and enable userfaultfd object. */ + + uffd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK); + if (uffd == -1) { + perror("userfaultfd"); + exit(1); + } + + uffdio_api.api = UFFD_API; + uffdio_api.features = 0; + if (ioctl(uffd, UFFDIO_API, &uffdio_api) == -1) { + perror("ioctl-UFFDIO_API"); + exit(1); + } + + one_page = allocate_zero_filled_hugepage(len); + + uffdio_register.range.start = (unsigned long)one_page; + uffdio_register.range.len = len; + uffdio_register.mode = UFFDIO_REGISTER_MODE_WP; + if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register) == -1) { + perror("ioctl-UFFDIO_REGISTER"); + exit(1); + } + + verify_rss_anon_split_huge_page_all_zeroes(one_page, nr_hpages, len); + printf("Split zero filled huge pages with uffd successful\n"); + free(one_page); +} + void split_pmd_thp(void) { char *one_page; @@ -431,6 +542,8 @@ int main(int argc, char **argv) fd_size = 2 * pmd_pagesize; + split_pmd_zero_pages(); + split_pmd_zero_pages_uffd(); split_pmd_thp(); split_pte_mapped_thp(); split_file_backed_thp(); diff --git a/tools/testing/selftests/mm/vm_util.c b/tools/testing/selftests/mm/vm_util.c index 5a62530da3b5..7b7e763ba8e3 100644 --- a/tools/testing/selftests/mm/vm_util.c +++ b/tools/testing/selftests/mm/vm_util.c @@ -12,6 +12,7 @@ #define PMD_SIZE_FILE_PATH "/sys/kernel/mm/transparent_hugepage/hpage_pmd_size" #define SMAP_FILE_PATH "/proc/self/smaps" +#define STATUS_FILE_PATH "/proc/self/status" #define MAX_LINE_LENGTH 500 unsigned int __page_size; @@ -171,6 +172,27 @@ uint64_t read_pmd_pagesize(void) return strtoul(buf, NULL, 10); } +uint64_t rss_anon(void) +{ + uint64_t rss_anon = 0; + FILE *fp; + char buffer[MAX_LINE_LENGTH]; + + fp = fopen(STATUS_FILE_PATH, "r"); + if (!fp) + ksft_exit_fail_msg("%s: Failed to open file %s\n", __func__, STATUS_FILE_PATH); + + if (!check_for_pattern(fp, "RssAnon:", buffer, sizeof(buffer))) + goto err_out; + + if (sscanf(buffer, "RssAnon:%10ld kB", &rss_anon) != 1) + ksft_exit_fail_msg("Reading status error\n"); + +err_out: + fclose(fp); + return rss_anon; +} + bool __check_huge(void *addr, char *pattern, int nr_hpages, uint64_t hpage_size) { diff --git a/tools/testing/selftests/mm/vm_util.h b/tools/testing/selftests/mm/vm_util.h index 9007c420d52c..71b75429f4a5 100644 --- a/tools/testing/selftests/mm/vm_util.h +++ b/tools/testing/selftests/mm/vm_util.h @@ -39,6 +39,7 @@ unsigned long pagemap_get_pfn(int fd, char *start); void clear_softdirty(void); bool check_for_pattern(FILE *fp, const char *pattern, char *buf, size_t len); uint64_t read_pmd_pagesize(void); +uint64_t rss_anon(void); bool check_huge_anon(void *addr, int nr_hpages, uint64_t hpage_size); bool check_huge_file(void *addr, int nr_hpages, uint64_t hpage_size); bool check_huge_shmem(void *addr, int nr_hpages, uint64_t hpage_size);