diff options
Diffstat (limited to 'tools/testing/selftests/mm/ksm_functional_tests.c')
-rw-r--r-- | tools/testing/selftests/mm/ksm_functional_tests.c | 137 |
1 files changed, 100 insertions, 37 deletions
diff --git a/tools/testing/selftests/mm/ksm_functional_tests.c b/tools/testing/selftests/mm/ksm_functional_tests.c index d615767e396b..37de82da9be7 100644 --- a/tools/testing/selftests/mm/ksm_functional_tests.c +++ b/tools/testing/selftests/mm/ksm_functional_tests.c @@ -28,6 +28,15 @@ #define MiB (1024 * KiB) #define FORK_EXEC_CHILD_PRG_NAME "ksm_fork_exec_child" +#define MAP_MERGE_FAIL ((void *)-1) +#define MAP_MERGE_SKIP ((void *)-2) + +enum ksm_merge_mode { + KSM_MERGE_PRCTL, + KSM_MERGE_MADVISE, + KSM_MERGE_NONE, /* PRCTL already set */ +}; + static int mem_fd; static int ksm_fd; static int ksm_full_scans_fd; @@ -146,33 +155,34 @@ static int ksm_unmerge(void) return 0; } -static char *mmap_and_merge_range(char val, unsigned long size, int prot, - bool use_prctl) +static char *__mmap_and_merge_range(char val, unsigned long size, int prot, + enum ksm_merge_mode mode) { char *map; + char *err_map = MAP_MERGE_FAIL; int ret; /* Stabilize accounting by disabling KSM completely. */ if (ksm_unmerge()) { - ksft_test_result_fail("Disabling (unmerging) KSM failed\n"); - return MAP_FAILED; + ksft_print_msg("Disabling (unmerging) KSM failed\n"); + return err_map; } if (get_my_merging_pages() > 0) { - ksft_test_result_fail("Still pages merged\n"); - return MAP_FAILED; + ksft_print_msg("Still pages merged\n"); + return err_map; } map = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANON, -1, 0); if (map == MAP_FAILED) { - ksft_test_result_fail("mmap() failed\n"); - return MAP_FAILED; + ksft_print_msg("mmap() failed\n"); + return err_map; } /* Don't use THP. Ignore if THP are not around on a kernel. */ if (madvise(map, size, MADV_NOHUGEPAGE) && errno != EINVAL) { - ksft_test_result_fail("MADV_NOHUGEPAGE failed\n"); + ksft_print_msg("MADV_NOHUGEPAGE failed\n"); goto unmap; } @@ -180,27 +190,36 @@ static char *mmap_and_merge_range(char val, unsigned long size, int prot, memset(map, val, size); if (mprotect(map, size, prot)) { - ksft_test_result_skip("mprotect() failed\n"); + ksft_print_msg("mprotect() failed\n"); + err_map = MAP_MERGE_SKIP; goto unmap; } - if (use_prctl) { + switch (mode) { + case KSM_MERGE_PRCTL: ret = prctl(PR_SET_MEMORY_MERGE, 1, 0, 0, 0); if (ret < 0 && errno == EINVAL) { - ksft_test_result_skip("PR_SET_MEMORY_MERGE not supported\n"); + ksft_print_msg("PR_SET_MEMORY_MERGE not supported\n"); + err_map = MAP_MERGE_SKIP; goto unmap; } else if (ret) { - ksft_test_result_fail("PR_SET_MEMORY_MERGE=1 failed\n"); + ksft_print_msg("PR_SET_MEMORY_MERGE=1 failed\n"); goto unmap; } - } else if (madvise(map, size, MADV_MERGEABLE)) { - ksft_test_result_fail("MADV_MERGEABLE failed\n"); - goto unmap; + break; + case KSM_MERGE_MADVISE: + if (madvise(map, size, MADV_MERGEABLE)) { + ksft_print_msg("MADV_MERGEABLE failed\n"); + goto unmap; + } + break; + case KSM_MERGE_NONE: + break; } /* Run KSM to trigger merging and wait. */ if (ksm_merge()) { - ksft_test_result_fail("Running KSM failed\n"); + ksft_print_msg("Running KSM failed\n"); goto unmap; } @@ -209,14 +228,31 @@ static char *mmap_and_merge_range(char val, unsigned long size, int prot, * accounted differently (depending on kernel support). */ if (val && !get_my_merging_pages()) { - ksft_test_result_fail("No pages got merged\n"); + ksft_print_msg("No pages got merged\n"); goto unmap; } return map; unmap: munmap(map, size); - return MAP_FAILED; + return err_map; +} + +static char *mmap_and_merge_range(char val, unsigned long size, int prot, + enum ksm_merge_mode mode) +{ + char *map; + char *ret = MAP_FAILED; + + map = __mmap_and_merge_range(val, size, prot, mode); + if (map == MAP_MERGE_FAIL) + ksft_test_result_fail("Merging memory failed"); + else if (map == MAP_MERGE_SKIP) + ksft_test_result_skip("Merging memory skipped"); + else + ret = map; + + return ret; } static void test_unmerge(void) @@ -226,7 +262,7 @@ static void test_unmerge(void) ksft_print_msg("[RUN] %s\n", __func__); - map = mmap_and_merge_range(0xcf, size, PROT_READ | PROT_WRITE, false); + map = mmap_and_merge_range(0xcf, size, PROT_READ | PROT_WRITE, KSM_MERGE_MADVISE); if (map == MAP_FAILED) return; @@ -264,7 +300,7 @@ static void test_unmerge_zero_pages(void) } /* Let KSM deduplicate zero pages. */ - map = mmap_and_merge_range(0x00, size, PROT_READ | PROT_WRITE, false); + map = mmap_and_merge_range(0x00, size, PROT_READ | PROT_WRITE, KSM_MERGE_MADVISE); if (map == MAP_FAILED) return; @@ -312,7 +348,7 @@ static void test_unmerge_discarded(void) ksft_print_msg("[RUN] %s\n", __func__); - map = mmap_and_merge_range(0xcf, size, PROT_READ | PROT_WRITE, false); + map = mmap_and_merge_range(0xcf, size, PROT_READ | PROT_WRITE, KSM_MERGE_MADVISE); if (map == MAP_FAILED) return; @@ -344,7 +380,7 @@ static void test_unmerge_uffd_wp(void) ksft_print_msg("[RUN] %s\n", __func__); - map = mmap_and_merge_range(0xcf, size, PROT_READ | PROT_WRITE, false); + map = mmap_and_merge_range(0xcf, size, PROT_READ | PROT_WRITE, KSM_MERGE_MADVISE); if (map == MAP_FAILED) return; @@ -439,6 +475,36 @@ static void test_prctl(void) ksft_test_result_pass("Setting/clearing PR_SET_MEMORY_MERGE works\n"); } +static int test_child_ksm(void) +{ + const unsigned int size = 2 * MiB; + char *map; + + /* Test if KSM is enabled for the process. */ + if (prctl(PR_GET_MEMORY_MERGE, 0, 0, 0, 0) != 1) + return -1; + + /* Test if merge could really happen. */ + map = __mmap_and_merge_range(0xcf, size, PROT_READ | PROT_WRITE, KSM_MERGE_NONE); + if (map == MAP_MERGE_FAIL) + return -2; + else if (map == MAP_MERGE_SKIP) + return -3; + + munmap(map, size); + return 0; +} + +static void test_child_ksm_err(int status) +{ + if (status == -1) + ksft_test_result_fail("unexpected PR_GET_MEMORY_MERGE result in child\n"); + else if (status == -2) + ksft_test_result_fail("Merge in child failed\n"); + else if (status == -3) + ksft_test_result_skip("Merge in child skipped\n"); +} + /* Verify that prctl ksm flag is inherited. */ static void test_prctl_fork(void) { @@ -458,7 +524,7 @@ static void test_prctl_fork(void) child_pid = fork(); if (!child_pid) { - exit(prctl(PR_GET_MEMORY_MERGE, 0, 0, 0, 0)); + exit(test_child_ksm()); } else if (child_pid < 0) { ksft_test_result_fail("fork() failed\n"); return; @@ -467,8 +533,11 @@ static void test_prctl_fork(void) if (waitpid(child_pid, &status, 0) < 0) { ksft_test_result_fail("waitpid() failed\n"); return; - } else if (WEXITSTATUS(status) != 1) { - ksft_test_result_fail("unexpected PR_GET_MEMORY_MERGE result in child\n"); + } + + status = WEXITSTATUS(status); + if (status) { + test_child_ksm_err(status); return; } @@ -480,12 +549,6 @@ static void test_prctl_fork(void) ksft_test_result_pass("PR_SET_MEMORY_MERGE value is inherited\n"); } -static int ksm_fork_exec_child(void) -{ - /* Test if KSM is enabled for the process. */ - return prctl(PR_GET_MEMORY_MERGE, 0, 0, 0, 0) == 1; -} - static void test_prctl_fork_exec(void) { int ret, status; @@ -518,7 +581,7 @@ static void test_prctl_fork_exec(void) if (WIFEXITED(status)) { status = WEXITSTATUS(status); if (status) { - ksft_test_result_fail("KSM not enabled\n"); + test_child_ksm_err(status); return; } } else { @@ -545,7 +608,7 @@ static void test_prctl_unmerge(void) ksft_print_msg("[RUN] %s\n", __func__); - map = mmap_and_merge_range(0xcf, size, PROT_READ | PROT_WRITE, true); + map = mmap_and_merge_range(0xcf, size, PROT_READ | PROT_WRITE, KSM_MERGE_PRCTL); if (map == MAP_FAILED) return; @@ -568,7 +631,7 @@ static void test_prot_none(void) ksft_print_msg("[RUN] %s\n", __func__); - map = mmap_and_merge_range(0x11, size, PROT_NONE, false); + map = mmap_and_merge_range(0x11, size, PROT_NONE, KSM_MERGE_MADVISE); if (map == MAP_FAILED) goto unmap; @@ -599,7 +662,7 @@ int main(int argc, char **argv) int err; if (argc > 1 && !strcmp(argv[1], FORK_EXEC_CHILD_PRG_NAME)) { - exit(ksm_fork_exec_child() == 1 ? 0 : 1); + exit(test_child_ksm()); } #ifdef __NR_userfaultfd @@ -646,5 +709,5 @@ int main(int argc, char **argv) if (err) ksft_exit_fail_msg("%d out of %d tests failed\n", err, ksft_test_num()); - return ksft_exit_pass(); + ksft_exit_pass(); } |