do_run_with_thp() prepares (PMD-sized) THP memory into different states before running tests. With the introduction of small-sized THP, we would like to reuse this logic to also test those smaller THP sizes. So let's add a size parameter which tells the function what size THP it should operate on. A separate commit will utilize this change to add new tests for small-sized THP, where available. Signed-off-by: Ryan Roberts <ryan.roberts@xxxxxxx> --- tools/testing/selftests/mm/cow.c | 146 +++++++++++++++++-------------- 1 file changed, 79 insertions(+), 67 deletions(-) diff --git a/tools/testing/selftests/mm/cow.c b/tools/testing/selftests/mm/cow.c index 7324ce5363c0..d03c453cfd5c 100644 --- a/tools/testing/selftests/mm/cow.c +++ b/tools/testing/selftests/mm/cow.c @@ -32,7 +32,7 @@ static size_t pagesize; static int pagemap_fd; -static size_t thpsize; +static size_t pmdsize; static int nr_hugetlbsizes; static size_t hugetlbsizes[10]; static int gup_fd; @@ -734,14 +734,14 @@ enum thp_run { THP_RUN_PARTIAL_SHARED, }; -static void do_run_with_thp(test_fn fn, enum thp_run thp_run) +static void do_run_with_thp(test_fn fn, enum thp_run thp_run, size_t size) { char *mem, *mmap_mem, *tmp, *mremap_mem = MAP_FAILED; - size_t size, mmap_size, mremap_size; + size_t mmap_size, mremap_size; int ret; - /* For alignment purposes, we need twice the thp size. */ - mmap_size = 2 * thpsize; + /* For alignment purposes, we need twice the requested size. */ + mmap_size = 2 * size; mmap_mem = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); if (mmap_mem == MAP_FAILED) { @@ -749,36 +749,40 @@ static void do_run_with_thp(test_fn fn, enum thp_run thp_run) return; } - /* We need a THP-aligned memory area. */ - mem = (char *)(((uintptr_t)mmap_mem + thpsize) & ~(thpsize - 1)); + /* We need to naturally align the memory area. */ + mem = (char *)(((uintptr_t)mmap_mem + size) & ~(size - 1)); - ret = madvise(mem, thpsize, MADV_HUGEPAGE); + ret = madvise(mem, size, MADV_HUGEPAGE); if (ret) { ksft_test_result_fail("MADV_HUGEPAGE failed\n"); goto munmap; } /* - * Try to populate a THP. Touch the first sub-page and test if we get - * another sub-page populated automatically. + * Try to populate a THP. Touch the first sub-page and test if + * we get the last sub-page populated automatically. */ mem[0] = 0; - if (!pagemap_is_populated(pagemap_fd, mem + pagesize)) { + if (!pagemap_is_populated(pagemap_fd, mem + size - pagesize)) { ksft_test_result_skip("Did not get a THP populated\n"); goto munmap; } - memset(mem, 0, thpsize); + memset(mem, 0, size); - size = thpsize; switch (thp_run) { case THP_RUN_PMD: case THP_RUN_PMD_SWAPOUT: + if (size != pmdsize) { + ksft_test_result_fail("test bug: can't PMD-map size\n"); + goto munmap; + } break; case THP_RUN_PTE: case THP_RUN_PTE_SWAPOUT: /* * Trigger PTE-mapping the THP by temporarily mapping a single - * subpage R/O. + * subpage R/O. This is a noop if the THP is not pmdsize (and + * therefore already PTE-mapped). */ ret = mprotect(mem + pagesize, pagesize, PROT_READ); if (ret) { @@ -797,7 +801,7 @@ static void do_run_with_thp(test_fn fn, enum thp_run thp_run) * Discard all but a single subpage of that PTE-mapped THP. What * remains is a single PTE mapping a single subpage. */ - ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DONTNEED); + ret = madvise(mem + pagesize, size - pagesize, MADV_DONTNEED); if (ret) { ksft_test_result_fail("MADV_DONTNEED failed\n"); goto munmap; @@ -809,7 +813,7 @@ static void do_run_with_thp(test_fn fn, enum thp_run thp_run) * Remap half of the THP. We need some new memory location * for that. */ - mremap_size = thpsize / 2; + mremap_size = size / 2; mremap_mem = mmap(NULL, mremap_size, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); if (mem == MAP_FAILED) { @@ -830,7 +834,7 @@ static void do_run_with_thp(test_fn fn, enum thp_run thp_run) * child. This will result in some parts of the THP never * have been shared. */ - ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DONTFORK); + ret = madvise(mem + pagesize, size - pagesize, MADV_DONTFORK); if (ret) { ksft_test_result_fail("MADV_DONTFORK failed\n"); goto munmap; @@ -844,7 +848,7 @@ static void do_run_with_thp(test_fn fn, enum thp_run thp_run) } wait(&ret); /* Allow for sharing all pages again. */ - ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DOFORK); + ret = madvise(mem + pagesize, size - pagesize, MADV_DOFORK); if (ret) { ksft_test_result_fail("MADV_DOFORK failed\n"); goto munmap; @@ -875,52 +879,60 @@ static void do_run_with_thp(test_fn fn, enum thp_run thp_run) munmap(mremap_mem, mremap_size); } -static void run_with_thp(test_fn fn, const char *desc) +static void run_with_thp(test_fn fn, const char *desc, size_t size) { - ksft_print_msg("[RUN] %s ... with THP\n", desc); - do_run_with_thp(fn, THP_RUN_PMD); + ksft_print_msg("[RUN] %s ... with THP (%zu kB)\n", + desc, size / 1024); + do_run_with_thp(fn, THP_RUN_PMD, size); } -static void run_with_thp_swap(test_fn fn, const char *desc) +static void run_with_thp_swap(test_fn fn, const char *desc, size_t size) { - ksft_print_msg("[RUN] %s ... with swapped-out THP\n", desc); - do_run_with_thp(fn, THP_RUN_PMD_SWAPOUT); + ksft_print_msg("[RUN] %s ... with swapped-out THP (%zu kB)\n", + desc, size / 1024); + do_run_with_thp(fn, THP_RUN_PMD_SWAPOUT, size); } -static void run_with_pte_mapped_thp(test_fn fn, const char *desc) +static void run_with_pte_mapped_thp(test_fn fn, const char *desc, size_t size) { - ksft_print_msg("[RUN] %s ... with PTE-mapped THP\n", desc); - do_run_with_thp(fn, THP_RUN_PTE); + ksft_print_msg("[RUN] %s ... with PTE-mapped THP (%zu kB)\n", + desc, size / 1024); + do_run_with_thp(fn, THP_RUN_PTE, size); } -static void run_with_pte_mapped_thp_swap(test_fn fn, const char *desc) +static void run_with_pte_mapped_thp_swap(test_fn fn, const char *desc, size_t size) { - ksft_print_msg("[RUN] %s ... with swapped-out, PTE-mapped THP\n", desc); - do_run_with_thp(fn, THP_RUN_PTE_SWAPOUT); + ksft_print_msg("[RUN] %s ... with swapped-out, PTE-mapped THP (%zu kB)\n", + desc, size / 1024); + do_run_with_thp(fn, THP_RUN_PTE_SWAPOUT, size); } -static void run_with_single_pte_of_thp(test_fn fn, const char *desc) +static void run_with_single_pte_of_thp(test_fn fn, const char *desc, size_t size) { - ksft_print_msg("[RUN] %s ... with single PTE of THP\n", desc); - do_run_with_thp(fn, THP_RUN_SINGLE_PTE); + ksft_print_msg("[RUN] %s ... with single PTE of THP (%zu kB)\n", + desc, size / 1024); + do_run_with_thp(fn, THP_RUN_SINGLE_PTE, size); } -static void run_with_single_pte_of_thp_swap(test_fn fn, const char *desc) +static void run_with_single_pte_of_thp_swap(test_fn fn, const char *desc, size_t size) { - ksft_print_msg("[RUN] %s ... with single PTE of swapped-out THP\n", desc); - do_run_with_thp(fn, THP_RUN_SINGLE_PTE_SWAPOUT); + ksft_print_msg("[RUN] %s ... with single PTE of swapped-out THP (%zu kB)\n", + desc, size / 1024); + do_run_with_thp(fn, THP_RUN_SINGLE_PTE_SWAPOUT, size); } -static void run_with_partial_mremap_thp(test_fn fn, const char *desc) +static void run_with_partial_mremap_thp(test_fn fn, const char *desc, size_t size) { - ksft_print_msg("[RUN] %s ... with partially mremap()'ed THP\n", desc); - do_run_with_thp(fn, THP_RUN_PARTIAL_MREMAP); + ksft_print_msg("[RUN] %s ... with partially mremap()'ed THP (%zu kB)\n", + desc, size / 1024); + do_run_with_thp(fn, THP_RUN_PARTIAL_MREMAP, size); } -static void run_with_partial_shared_thp(test_fn fn, const char *desc) +static void run_with_partial_shared_thp(test_fn fn, const char *desc, size_t size) { - ksft_print_msg("[RUN] %s ... with partially shared THP\n", desc); - do_run_with_thp(fn, THP_RUN_PARTIAL_SHARED); + ksft_print_msg("[RUN] %s ... with partially shared THP (%zu kB)\n", + desc, size / 1024); + do_run_with_thp(fn, THP_RUN_PARTIAL_SHARED, size); } static void run_with_hugetlb(test_fn fn, const char *desc, size_t hugetlbsize) @@ -1091,15 +1103,15 @@ static void run_anon_test_case(struct test_case const *test_case) run_with_base_page(test_case->fn, test_case->desc); run_with_base_page_swap(test_case->fn, test_case->desc); - if (thpsize) { - run_with_thp(test_case->fn, test_case->desc); - run_with_thp_swap(test_case->fn, test_case->desc); - run_with_pte_mapped_thp(test_case->fn, test_case->desc); - run_with_pte_mapped_thp_swap(test_case->fn, test_case->desc); - run_with_single_pte_of_thp(test_case->fn, test_case->desc); - run_with_single_pte_of_thp_swap(test_case->fn, test_case->desc); - run_with_partial_mremap_thp(test_case->fn, test_case->desc); - run_with_partial_shared_thp(test_case->fn, test_case->desc); + if (pmdsize) { + run_with_thp(test_case->fn, test_case->desc, pmdsize); + run_with_thp_swap(test_case->fn, test_case->desc, pmdsize); + run_with_pte_mapped_thp(test_case->fn, test_case->desc, pmdsize); + run_with_pte_mapped_thp_swap(test_case->fn, test_case->desc, pmdsize); + run_with_single_pte_of_thp(test_case->fn, test_case->desc, pmdsize); + run_with_single_pte_of_thp_swap(test_case->fn, test_case->desc, pmdsize); + run_with_partial_mremap_thp(test_case->fn, test_case->desc, pmdsize); + run_with_partial_shared_thp(test_case->fn, test_case->desc, pmdsize); } for (i = 0; i < nr_hugetlbsizes; i++) run_with_hugetlb(test_case->fn, test_case->desc, @@ -1120,7 +1132,7 @@ static int tests_per_anon_test_case(void) { int tests = 2 + nr_hugetlbsizes; - if (thpsize) + if (pmdsize) tests += 8; return tests; } @@ -1329,7 +1341,7 @@ static void run_anon_thp_test_cases(void) { int i; - if (!thpsize) + if (!pmdsize) return; ksft_print_msg("[INFO] Anonymous THP tests\n"); @@ -1338,13 +1350,13 @@ static void run_anon_thp_test_cases(void) struct test_case const *test_case = &anon_thp_test_cases[i]; ksft_print_msg("[RUN] %s\n", test_case->desc); - do_run_with_thp(test_case->fn, THP_RUN_PMD); + do_run_with_thp(test_case->fn, THP_RUN_PMD, pmdsize); } } static int tests_per_anon_thp_test_case(void) { - return thpsize ? 1 : 0; + return pmdsize ? 1 : 0; } typedef void (*non_anon_test_fn)(char *mem, const char *smem, size_t size); @@ -1419,7 +1431,7 @@ static void run_with_huge_zeropage(non_anon_test_fn fn, const char *desc) } /* For alignment purposes, we need twice the thp size. */ - mmap_size = 2 * thpsize; + mmap_size = 2 * pmdsize; mmap_mem = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); if (mmap_mem == MAP_FAILED) { @@ -1434,11 +1446,11 @@ static void run_with_huge_zeropage(non_anon_test_fn fn, const char *desc) } /* We need a THP-aligned memory area. */ - mem = (char *)(((uintptr_t)mmap_mem + thpsize) & ~(thpsize - 1)); - smem = (char *)(((uintptr_t)mmap_smem + thpsize) & ~(thpsize - 1)); + mem = (char *)(((uintptr_t)mmap_mem + pmdsize) & ~(pmdsize - 1)); + smem = (char *)(((uintptr_t)mmap_smem + pmdsize) & ~(pmdsize - 1)); - ret = madvise(mem, thpsize, MADV_HUGEPAGE); - ret |= madvise(smem, thpsize, MADV_HUGEPAGE); + ret = madvise(mem, pmdsize, MADV_HUGEPAGE); + ret |= madvise(smem, pmdsize, MADV_HUGEPAGE); if (ret) { ksft_test_result_fail("MADV_HUGEPAGE failed\n"); goto munmap; @@ -1457,7 +1469,7 @@ static void run_with_huge_zeropage(non_anon_test_fn fn, const char *desc) goto munmap; } - fn(mem, smem, thpsize); + fn(mem, smem, pmdsize); munmap: munmap(mmap_mem, mmap_size); if (mmap_smem != MAP_FAILED) @@ -1650,7 +1662,7 @@ static void run_non_anon_test_case(struct non_anon_test_case const *test_case) run_with_zeropage(test_case->fn, test_case->desc); run_with_memfd(test_case->fn, test_case->desc); run_with_tmpfile(test_case->fn, test_case->desc); - if (thpsize) + if (pmdsize) run_with_huge_zeropage(test_case->fn, test_case->desc); for (i = 0; i < nr_hugetlbsizes; i++) run_with_memfd_hugetlb(test_case->fn, test_case->desc, @@ -1671,7 +1683,7 @@ static int tests_per_non_anon_test_case(void) { int tests = 3 + nr_hugetlbsizes; - if (thpsize) + if (pmdsize) tests += 1; return tests; } @@ -1681,10 +1693,10 @@ int main(int argc, char **argv) int err; pagesize = getpagesize(); - thpsize = read_pmd_pagesize(); - if (thpsize) - ksft_print_msg("[INFO] detected THP size: %zu KiB\n", - thpsize / 1024); + pmdsize = read_pmd_pagesize(); + if (pmdsize) + ksft_print_msg("[INFO] detected PMD-mapped THP size: %zu KiB\n", + pmdsize / 1024); nr_hugetlbsizes = detect_hugetlb_page_sizes(hugetlbsizes, ARRAY_SIZE(hugetlbsizes)); detect_huge_zeropage(); -- 2.25.1