Added a new command 'mthp_khugepaged' for mTHP collapse, along with the '-c' parameter to specify the collapse order. Additionally, added mTHP collapse test cases for 'collapse_full', 'collapse_empty', and 'collapse_single_mthp' for both anonymous pages and shmem. All khugepaged test cases passed.
Signed-off-by: Baolin Wang <[email protected]> --- tools/testing/selftests/mm/khugepaged.c | 135 +++++++++++++++++++--- tools/testing/selftests/mm/run_vmtests.sh | 4 + 2 files changed, 120 insertions(+), 19 deletions(-) diff --git a/tools/testing/selftests/mm/khugepaged.c b/tools/testing/selftests/mm/khugepaged.c index f69be6be0ecd..8975be5b7b2f 100644 --- a/tools/testing/selftests/mm/khugepaged.c +++ b/tools/testing/selftests/mm/khugepaged.c @@ -26,9 +26,11 @@ #define BASE_ADDR ((void *)(1UL << 30)) static unsigned long hpage_pmd_size; +static int hpage_pmd_order; static unsigned long page_size; static int hpage_pmd_nr; static int anon_order; +static int collapse_order; #define PID_SMAPS "/proc/self/smaps" #define TEST_FILE "collapse_test_file" @@ -69,6 +71,7 @@ struct collapse_context { }; static struct collapse_context *khugepaged_context; +static struct collapse_context *mthp_khugepaged_context; static struct collapse_context *madvise_context; struct file_info { @@ -554,25 +557,25 @@ static void madvise_collapse(const char *msg, char *p, int nr_hpages, } #define TICK 500000 -static bool wait_for_scan(const char *msg, char *p, int nr_hpages, - struct mem_ops *ops) +static bool wait_for_scan(const char *msg, char *p, unsigned long size, + int nr_hpages, int collap_order, struct mem_ops *ops) { - unsigned long size = nr_hpages * hpage_pmd_size; + unsigned long hpage_size = page_size << collap_order; int full_scans; int timeout = 6; /* 3 seconds */ /* Sanity check */ - if (!ops->check_huge(p, size, 0, hpage_pmd_size)) + if (!ops->check_huge(p, size, 0, hpage_size)) ksft_exit_fail_msg("Unexpected huge page\n"); - madvise(p, nr_hpages * hpage_pmd_size, MADV_HUGEPAGE); + madvise(p, size, MADV_HUGEPAGE); /* Wait until the second full_scan completed */ full_scans = thp_read_num("khugepaged/full_scans") + 2; ksft_print_msg("%s...", msg); while (timeout--) { - if (ops->check_huge(p, size, nr_hpages, hpage_pmd_size)) + if (ops->check_huge(p, size, nr_hpages, hpage_size)) break; if (thp_read_num("khugepaged/full_scans") >= full_scans) break; @@ -595,7 +598,7 @@ static void khugepaged_collapse(const char *msg, char *p, int nr_hpages, if (!is_tmpfs(ops) && ops == &__read_write_file_write_ops) expect = false; - if (wait_for_scan(msg, p, nr_hpages, ops)) { + if (wait_for_scan(msg, p, size, nr_hpages, hpage_pmd_order, ops)) { if (expect) fail("Timeout"); else @@ -617,12 +620,65 @@ static void khugepaged_collapse(const char *msg, char *p, int nr_hpages, fail("Fail"); } +static void mthp_khugepaged_collapse(const char *msg, char *p, int nr_hpages, + struct mem_ops *ops, bool expect) +{ + unsigned long hpage_size = page_size << collapse_order; + struct thp_settings settings = *thp_current_settings(); + /* mTHP collpase only allocates PMD sized memory */ + unsigned long size = hpage_pmd_size; + + /* Set mTHP setting for mTHP collapse */ + if (ops == &__anon_ops) { + settings.thp_enabled = THP_NEVER; + settings.hugepages[collapse_order].enabled = THP_ALWAYS; + } else if (ops == &__shmem_ops) { + settings.shmem_enabled = SHMEM_NEVER; + settings.shmem_hugepages[collapse_order].enabled = SHMEM_ALWAYS; + } + + thp_push_settings(&settings); + + if (wait_for_scan(msg, p, size, nr_hpages, collapse_order, ops)) { + if (expect) + fail("Timeout"); + else + success("OK"); + + /* Restore THP settings for mTHP collapse. */ + thp_pop_settings(); + return; + } + + /* + * For file and shmem memory, khugepaged only retracts pte entries after + * putting the new hugepage in the page cache. The hugepage must be + * subsequently refaulted to install the pmd mapping for the mm. + */ + if (ops != &__anon_ops) + ops->fault(p, 0, nr_hpages * hpage_size); + + if (ops->check_huge(p, size, expect ? nr_hpages : 0, hpage_size)) + success("OK"); + else + fail("Fail"); + + /* Restore THP settings for mTHP collapse. */ + thp_pop_settings(); +} + static struct collapse_context __khugepaged_context = { .collapse = &khugepaged_collapse, .enforce_pte_scan_limits = true, .name = "khugepaged", }; +static struct collapse_context __mthp_khugepaged_context = { + .collapse = &mthp_khugepaged_collapse, + .enforce_pte_scan_limits = true, + .name = "mthp_khugepaged", +}; + static struct collapse_context __madvise_context = { .collapse = &madvise_collapse, .enforce_pte_scan_limits = false, @@ -661,10 +717,17 @@ static void alloc_at_fault(void) static void collapse_full(struct collapse_context *c, struct mem_ops *ops) { void *p; - int nr_hpages = 4; + int nr_pmds = 4, nr_hpages = 4; unsigned long size = nr_hpages * hpage_pmd_size; - p = ops->setup_area(nr_hpages); + /* Only try 1 PMD sized range for mTHP collapse. */ + if (c == &__mthp_khugepaged_context) { + nr_pmds = 1; + nr_hpages = 1 << (hpage_pmd_order - collapse_order); + size = hpage_pmd_size; + } + + p = ops->setup_area(nr_pmds); ops->fault(p, 0, size); c->collapse("Collapse multiple fully populated PTE table", p, nr_hpages, ops, true); @@ -676,10 +739,31 @@ static void collapse_full(struct collapse_context *c, struct mem_ops *ops) static void collapse_empty(struct collapse_context *c, struct mem_ops *ops) { + int nr_hpages = 1; + void *p; + + if (c == &__mthp_khugepaged_context) + nr_hpages = 1 << (hpage_pmd_order - collapse_order); + + p = ops->setup_area(1); + c->collapse("Do not collapse empty PTE table", p, nr_hpages, ops, false); + ops->cleanup_area(p, hpage_pmd_size); + ksft_test_result_report(exit_status, "%s\n", __func__); +} + +static void collapse_single_mthp(struct collapse_context *c, struct mem_ops *ops) +{ + unsigned long hpage_size = page_size << collapse_order; void *p; p = ops->setup_area(1); - c->collapse("Do not collapse empty PTE table", p, 1, ops, false); + /* + * Only fault collapse_order sized ranges, and only check 1 + * collapse_order sized huge page. + */ + ops->fault(p, 0, hpage_size); + c->collapse("Collapse PTE table with half PTE entries present", + p, 1, ops, true); ops->cleanup_area(p, hpage_pmd_size); ksft_test_result_report(exit_status, "%s\n", __func__); } @@ -1081,8 +1165,8 @@ static void madvise_retracted_page_tables(struct collapse_context *c, ops->fault(p, 0, size); /* Let khugepaged collapse and leave pmd cleared */ - if (wait_for_scan("Collapse and leave PMD cleared", p, nr_hpages, - ops)) { + if (wait_for_scan("Collapse and leave PMD cleared", p, size, nr_hpages, + hpage_pmd_order, ops)) { fail("Timeout"); return; } @@ -1098,7 +1182,7 @@ static void usage(void) { fprintf(stderr, "\nUsage: ./khugepaged [OPTIONS] <test type> [dir]\n\n"); fprintf(stderr, "\t<test type>\t: <context>:<mem_type>\n"); - fprintf(stderr, "\t<context>\t: [all|khugepaged|madvise]\n"); + fprintf(stderr, "\t<context>\t: [all|khugepaged|mthp_khugepaged|madvise]\n"); fprintf(stderr, "\t<mem_type>\t: [all|anon|file|shmem]\n"); fprintf(stderr, "\n\t\"file,all\" mem_type requires [dir] argument\n"); fprintf(stderr, "\n\t\"file,all\" mem_type requires a file system\n"); @@ -1109,6 +1193,7 @@ static void usage(void) fprintf(stderr, "\t\t-h: This help message.\n"); fprintf(stderr, "\t\t-s: mTHP size, expressed as page order.\n"); fprintf(stderr, "\t\t Defaults to 0. Use this size for anon or shmem allocations.\n"); + fprintf(stderr, "\t\t-c: collapse order for mTHP collapse, expressed as page order.\n"); exit(1); } @@ -1118,11 +1203,14 @@ static void parse_test_type(int argc, char **argv) char *buf; const char *token; - while ((opt = getopt(argc, argv, "s:h")) != -1) { + while ((opt = getopt(argc, argv, "s:c:h")) != -1) { switch (opt) { case 's': anon_order = atoi(optarg); break; + case 'c': + collapse_order = atoi(optarg); + break; case 'h': default: usage(); @@ -1148,6 +1236,10 @@ static void parse_test_type(int argc, char **argv) madvise_context = &__madvise_context; } else if (!strcmp(token, "khugepaged")) { khugepaged_context = &__khugepaged_context; + } else if (!strcmp(token, "mthp_khugepaged")) { + mthp_khugepaged_context = &__mthp_khugepaged_context; + if (collapse_order == 0 || collapse_order >= hpage_pmd_order) + usage(); } else if (!strcmp(token, "madvise")) { madvise_context = &__madvise_context; } else { @@ -1213,7 +1305,6 @@ static int nr_test_cases; int main(int argc, char **argv) { - int hpage_pmd_order; struct thp_settings default_settings = { .thp_enabled = THP_MADVISE, .thp_defrag = THP_DEFRAG_ALWAYS, @@ -1239,10 +1330,6 @@ int main(int argc, char **argv) if (!thp_is_enabled()) ksft_exit_skip("Transparent Hugepages not available\n"); - parse_test_type(argc, argv); - - setbuf(stdout, NULL); - page_size = getpagesize(); hpage_pmd_size = read_pmd_pagesize(); if (!hpage_pmd_size) @@ -1250,6 +1337,10 @@ int main(int argc, char **argv) hpage_pmd_nr = hpage_pmd_size / page_size; hpage_pmd_order = __builtin_ctz(hpage_pmd_nr); + parse_test_type(argc, argv); + + setbuf(stdout, NULL); + default_settings.khugepaged.max_ptes_none = hpage_pmd_nr - 1; default_settings.khugepaged.max_ptes_swap = hpage_pmd_nr / 8; default_settings.khugepaged.max_ptes_shared = hpage_pmd_nr / 2; @@ -1267,6 +1358,8 @@ int main(int argc, char **argv) TEST(collapse_full, khugepaged_context, read_write_file_read_ops); TEST(collapse_full, khugepaged_context, read_write_file_write_ops); TEST(collapse_full, khugepaged_context, shmem_ops); + TEST(collapse_full, mthp_khugepaged_context, anon_ops); + TEST(collapse_full, mthp_khugepaged_context, shmem_ops); TEST(collapse_full, madvise_context, anon_ops); TEST(collapse_full, madvise_context, read_only_file_ops); TEST(collapse_full, madvise_context, read_write_file_read_ops); @@ -1274,8 +1367,12 @@ int main(int argc, char **argv) TEST(collapse_full, madvise_context, shmem_ops); TEST(collapse_empty, khugepaged_context, anon_ops); + TEST(collapse_empty, mthp_khugepaged_context, anon_ops); TEST(collapse_empty, madvise_context, anon_ops); + TEST(collapse_single_mthp, mthp_khugepaged_context, anon_ops); + TEST(collapse_single_mthp, mthp_khugepaged_context, shmem_ops); + TEST(collapse_single_pte_entry, khugepaged_context, anon_ops); TEST(collapse_single_pte_entry, khugepaged_context, read_only_file_ops); TEST(collapse_single_pte_entry, khugepaged_context, read_write_file_read_ops); diff --git a/tools/testing/selftests/mm/run_vmtests.sh b/tools/testing/selftests/mm/run_vmtests.sh index 8c296dedf047..c0f4f3e5f1f1 100755 --- a/tools/testing/selftests/mm/run_vmtests.sh +++ b/tools/testing/selftests/mm/run_vmtests.sh @@ -411,6 +411,10 @@ CATEGORY="thp" run_test ./khugepaged all:shmem CATEGORY="thp" run_test ./khugepaged -s 4 all:shmem +CATEGORY="thp" run_test ./khugepaged -c 4 mthp_khugepaged:anon + +CATEGORY="thp" run_test ./khugepaged -c 4 mthp_khugepaged:shmem + # Try to create XFS if not provided if [ -z "${SPLIT_HUGE_PAGE_TEST_XFS_PATH}" ]; then if test_selected "thp"; then -- 2.47.3
