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.
Patch 1 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 with no dependency on kselftest. Patch 2 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). Results are reported as standard TAP output with no command-line arguments required. --- These patches apply on top of mm/mm-new. 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 Sarthak Sharma (2): 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 | 1 + tools/mm/.gitignore | 2 + tools/mm/Makefile | 6 +- tools/mm/gup_bench.c | 491 ++++++++++++++++++++ tools/testing/selftests/mm/gup_test.c | 536 +++++++++++++--------- tools/testing/selftests/mm/run_vmtests.sh | 37 +- 7 files changed, 822 insertions(+), 263 deletions(-) create mode 100644 tools/mm/gup_bench.c base-commit: 2c3f468717231305523ddcd94d91c0d5e4a72419 -- 2.39.5
