gup_test.c currently serves two distinct purposes: microbenchmarking (GUP_FAST_BENCHMARK, PIN_FAST_BENCHMARK, PIN_LONGTERM_BENCHMARK) and functional correctness testing (GUP_BASIC_TEST, PIN_BASIC_TEST, DUMP_USER_PAGES_TEST). Mixing these in a single binary means functional tests cannot be run or reported individually and run_vmtests.sh must invoke the binary multiple times with different flag combinations to cover all configurations.
This patch series separates the two concerns: tools/mm/gup_bench for benchmarking and tools/testing/selftests/mm/gup_test for functional testing. To avoid duplicating HugeTLB and related file helpers, the series first moves the common helper code to tools/lib/mm/ so it can be shared by both selftests and tools/mm. Patch 1 adds tools/lib/mm/file_utils.[ch], moving read_file(), write_file(), read_num() and write_num() out of vm_util.c into a shared helper without a kselftest dependency. It also adds tools/lib/mm/ to the MEMORY MANAGEMENT - MISC entry in MAINTAINERS. Patch 2 moves hugepage_settings.[ch] from selftests/mm to tools/lib/mm/, updates the selftests/mm users to include it from there and removes the remaining kselftest dependency from the implementation while dropping non-fatal hugetlb informational prints from the shared helper. Patch 3 adds tools/mm/gup_bench.c, a standalone microbenchmark for GUP_FAST, PIN_FAST and PIN_LONGTERM via the CONFIG_GUP_TEST debugfs interface. It runs the same matrix of configurations as the old run_gup_matrix() shell function (all three commands, read/write, private/shared, four page counts, THP on/off, hugetlb), but as a standalone C program under tools/mm using the shared tools/lib/mm helpers. Patch 4 rewrites gup_test.c as a kselftest harness-based selftest. It covers all five GUP kernel functions (get_user_pages, get_user_pages_fast, pin_user_pages, pin_user_pages_fast, pin_user_pages with FOLL_LONGTERM) plus DUMP_USER_PAGES_TEST, across 12 mapping configurations (THP on, THP off and hugetlb, each across private/shared and read/write variants) and four batch sizes (1, 512, 123, all pages). It also preserves the old sparse dump coverage for pages 0, 19 and 0x1000. Results are reported as standard TAP output with no command-line arguments required. --- These patches apply on top of mm/mm-new. Changes in v3: - Address v2 feedback from Sashiko - Add shared file_utils helpers under tools/lib/mm - Move hugepage_settings out of selftests and into tools/lib/mm - Convert gup_bench to use the shared tools/lib/mm helpers - Guard against invalid thread counts in gup_bench - Handle thread-array allocation failure cleanly in gup_bench - Restore hugetlb settings on setup failure in gup_test - Add sparse DUMP_USER_PAGES_TEST coverage for pages 0, 19 and 0x1000 in gup_test Changes in v2: - Address v1 feedback from Sashiko - Add fast and longterm GUP/PUP coverage - Sweep nr_pages_per_call over 1, 512, 123 and all pages - Call madvise(MADV_NOHUGEPAGE) in non-THP variants - Use 256 MB for hugetlb fixtures - Use hugetlb_restore_settings() in FIXTURE_TEARDOWN instead of atexit() - Add TH_LOG to report nr_pages_per_call for each iteration - Update Documentation/core-api/pin_user_pages.rst unit testing section Previous versions: v2: https://lore.kernel.org/all/[email protected]/ v1: https://lore.kernel.org/all/[email protected]/ --- Sarthak Sharma (4): tools/lib/mm: add shared file helpers tools/lib/mm: move hugepage_settings out of selftests tools/mm: add a standalone GUP microbenchmark selftests/mm: rewrite gup_test as a standalone harness-based selftest Documentation/core-api/pin_user_pages.rst | 12 +- MAINTAINERS | 2 + tools/lib/mm/file_utils.c | 83 +++ tools/lib/mm/file_utils.h | 12 + .../selftests => lib}/mm/hugepage_settings.c | 14 +- .../selftests => lib}/mm/hugepage_settings.h | 0 tools/mm/.gitignore | 2 + tools/mm/Makefile | 10 +- tools/mm/gup_bench.c | 390 ++++++++++++ tools/testing/selftests/mm/Makefile | 8 +- tools/testing/selftests/mm/compaction_test.c | 2 +- tools/testing/selftests/mm/cow.c | 2 +- .../selftests/mm/folio_split_race_test.c | 3 +- tools/testing/selftests/mm/guard-regions.c | 3 +- tools/testing/selftests/mm/gup_longterm.c | 2 +- tools/testing/selftests/mm/gup_test.c | 587 +++++++++++------- tools/testing/selftests/mm/hmm-tests.c | 6 +- tools/testing/selftests/mm/hugetlb-madvise.c | 3 +- tools/testing/selftests/mm/hugetlb-mmap.c | 3 +- tools/testing/selftests/mm/hugetlb-mremap.c | 3 +- tools/testing/selftests/mm/hugetlb-shm.c | 2 +- .../selftests/mm/hugetlb-soft-offline.c | 2 +- tools/testing/selftests/mm/hugetlb-vmemmap.c | 3 +- tools/testing/selftests/mm/hugetlb_dio.c | 3 +- .../selftests/mm/hugetlb_fault_after_madv.c | 2 +- .../selftests/mm/hugetlb_madv_vs_map.c | 2 +- tools/testing/selftests/mm/khugepaged.c | 3 +- tools/testing/selftests/mm/ksm_tests.c | 2 +- tools/testing/selftests/mm/migration.c | 6 +- tools/testing/selftests/mm/pagemap_ioctl.c | 2 +- .../testing/selftests/mm/prctl_thp_disable.c | 2 +- tools/testing/selftests/mm/protection_keys.c | 2 +- tools/testing/selftests/mm/run_vmtests.sh | 37 +- tools/testing/selftests/mm/soft-dirty.c | 2 +- .../selftests/mm/split_huge_page_test.c | 4 +- tools/testing/selftests/mm/thuge-gen.c | 3 +- tools/testing/selftests/mm/transhuge-stress.c | 3 +- tools/testing/selftests/mm/uffd-common.h | 2 +- tools/testing/selftests/mm/uffd-wp-mremap.c | 3 +- .../selftests/mm/va_high_addr_switch.c | 2 +- tools/testing/selftests/mm/vm_util.c | 65 +- tools/testing/selftests/mm/vm_util.h | 5 - 42 files changed, 935 insertions(+), 369 deletions(-) create mode 100644 tools/lib/mm/file_utils.c create mode 100644 tools/lib/mm/file_utils.h rename tools/{testing/selftests => lib}/mm/hugepage_settings.c (98%) rename tools/{testing/selftests => lib}/mm/hugepage_settings.h (100%) create mode 100644 tools/mm/gup_bench.c base-commit: 4c6512d033e5e9469cc76d07512c24a0ee0ac207 -- 2.39.5
