diff options
Diffstat (limited to 'tools/testing/selftests')
-rw-r--r-- | tools/testing/selftests/vm/khugepaged.c | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/tools/testing/selftests/vm/khugepaged.c b/tools/testing/selftests/vm/khugepaged.c index ef67a8a3d784..51b89cedd09d 100644 --- a/tools/testing/selftests/vm/khugepaged.c +++ b/tools/testing/selftests/vm/khugepaged.c @@ -78,6 +78,7 @@ struct khugepaged_settings { unsigned int scan_sleep_millisecs; unsigned int max_ptes_none; unsigned int max_ptes_swap; + unsigned int max_ptes_shared; unsigned long pages_to_scan; }; @@ -277,6 +278,7 @@ static void write_settings(struct settings *settings) khugepaged->scan_sleep_millisecs); write_num("khugepaged/max_ptes_none", khugepaged->max_ptes_none); write_num("khugepaged/max_ptes_swap", khugepaged->max_ptes_swap); + write_num("khugepaged/max_ptes_shared", khugepaged->max_ptes_shared); write_num("khugepaged/pages_to_scan", khugepaged->pages_to_scan); } @@ -313,6 +315,7 @@ static void save_settings(void) read_num("khugepaged/scan_sleep_millisecs"), .max_ptes_none = read_num("khugepaged/max_ptes_none"), .max_ptes_swap = read_num("khugepaged/max_ptes_swap"), + .max_ptes_shared = read_num("khugepaged/max_ptes_shared"), .pages_to_scan = read_num("khugepaged/pages_to_scan"), }; success("OK"); @@ -896,12 +899,90 @@ static void collapse_fork_compound(void) fail("Fail"); fill_memory(p, 0, page_size); + write_num("khugepaged/max_ptes_shared", hpage_pmd_nr - 1); if (wait_for_scan("Collapse PTE table full of compound pages in child", p)) fail("Timeout"); else if (check_huge(p)) success("OK"); else fail("Fail"); + write_num("khugepaged/max_ptes_shared", + default_settings.khugepaged.max_ptes_shared); + + validate_memory(p, 0, hpage_pmd_size); + munmap(p, hpage_pmd_size); + exit(exit_status); + } + + wait(&wstatus); + exit_status += WEXITSTATUS(wstatus); + + printf("Check if parent still has huge page..."); + if (check_huge(p)) + success("OK"); + else + fail("Fail"); + validate_memory(p, 0, hpage_pmd_size); + munmap(p, hpage_pmd_size); +} + +static void collapse_max_ptes_shared() +{ + int max_ptes_shared = read_num("khugepaged/max_ptes_shared"); + int wstatus; + void *p; + + p = alloc_mapping(); + + printf("Allocate huge page..."); + madvise(p, hpage_pmd_size, MADV_HUGEPAGE); + fill_memory(p, 0, hpage_pmd_size); + if (check_huge(p)) + success("OK"); + else + fail("Fail"); + + printf("Share huge page over fork()..."); + if (!fork()) { + /* Do not touch settings on child exit */ + skip_settings_restore = true; + exit_status = 0; + + if (check_huge(p)) + success("OK"); + else + fail("Fail"); + + printf("Trigger CoW on page %d of %d...", + hpage_pmd_nr - max_ptes_shared - 1, hpage_pmd_nr); + fill_memory(p, 0, (hpage_pmd_nr - max_ptes_shared - 1) * page_size); + if (!check_huge(p)) + success("OK"); + else + fail("Fail"); + + if (wait_for_scan("Do not collapse with max_ptes_shared exceeded", p)) + fail("Timeout"); + else if (!check_huge(p)) + success("OK"); + else + fail("Fail"); + + printf("Trigger CoW on page %d of %d...", + hpage_pmd_nr - max_ptes_shared, hpage_pmd_nr); + fill_memory(p, 0, (hpage_pmd_nr - max_ptes_shared) * page_size); + if (!check_huge(p)) + success("OK"); + else + fail("Fail"); + + + if (wait_for_scan("Collapse with max_ptes_shared PTEs shared", p)) + fail("Timeout"); + else if (check_huge(p)) + success("OK"); + else + fail("Fail"); validate_memory(p, 0, hpage_pmd_size); munmap(p, hpage_pmd_size); @@ -930,6 +1011,7 @@ int main(void) 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; default_settings.khugepaged.pages_to_scan = hpage_pmd_nr * 8; save_settings(); @@ -947,6 +1029,7 @@ int main(void) collapse_compound_extreme(); collapse_fork(); collapse_fork_compound(); + collapse_max_ptes_shared(); restore_settings(0); } |