gup_test.c currently serves two separate purposes: benchmarking (GUP_FAST_BENCHMARK, PIN_FAST_BENCHMARK and PIN_LONGTERM_BENCHMARK) and functional testing (GUP_BASIC_TEST, PIN_BASIC_TEST and DUMP_USER_PAGES_TEST). Keeping both in one program makes the functional tests harder to run and report individually, while run_vmtests.sh has to invoke the program repeatedly with different options.
Separate these roles into tools/mm/gup_bench for benchmarking and tools/testing/selftests/mm/gup for functional testing. Move the shared file and hugepage helpers to tools/lib/mm/ so both programs can use them without duplicating the implementation. Patch 1 makes read_file(), write_file(), read_num(), write_num() and write_num_ignore_einval() return errors to their callers instead of exiting. It also makes read_num() reject negative and malformed values and updates the existing callers to handle failures. Patch 2 moves these file helpers from vm_util.c to tools/lib/mm/. It keeps them available to the mm selftests through vm_util.h and adjusts the selftests build accordingly. Patch 3 moves hugepage_settings.[ch] from selftests/mm to tools/lib/mm/. It also removes its kselftest dependency while preserving TAP-compatible diagnostics for selftest users. Patch 4 moves the existing gup_test implementation from selftests/mm to tools/mm as gup_bench. This keeps the code movement separate from the subsequent changes and makes it easier to review. Patch 5 removes the functional test modes and kselftest dependency from gup_bench. When run without arguments, it performs one GUP_FAST benchmark using the existing defaults instead of running the whole matrix. Other benchmark configurations can be selected through command-line options. Patch 6 adds a new harness-based GUP selftest. It covers THP, non-THP and HugeTLB mappings across private/shared and read/write variants. For each variant, it tests get_user_pages(), get_user_pages_fast(), pin_user_pages(), pin_user_pages_fast(), long-term pinning and both dump modes using four batch sizes. It also preserves the existing sparse dump coverage for pages 0, 19 and 0x1000. The HugeTLB variants share a one-time setup of 128 default-sized huge pages. --- I think Sashiko might complain about some "what if the user inputs this and that" scenarios in patch 5, but I intentionally am not covering those now, agreeing with Mike's point that a user will be wise enough to input sane values to run a benchmark. Those checks increase churn and make the patch harder to review. Changes in v7: - Rebase onto mm-unstable - Address feedback from Mike and Sashiko - Make read_file() return 0 on success and tighten read_num() parsing - Move write_num_ignore_einval() with the shared file helpers - Keep the existing gup_bench argument parsing and avoid unrelated checks - Set up 128 HugeTLB pages once for all HugeTLB selftest variants Changes in v6: - Rebase onto v7.2-rc5 - Address feedback from David, Mark, John, Dev and Sashiko - Keep the shared file helpers silent and let callers report errors - Move the existing gup_test into tools/mm before changing its behaviour - Report ioctl failures from gup_bench worker threads - Remove the default benchmark matrix and run one default benchmark instead - Add the new harness-based functional selftest in a separate final patch - Drop the unrelated thp_swap_allocator_test .gitignore change Changes in v5: - Rebase onto v7.2-rc3 - Address feedback from Mike, John, Dev and Sashiko - Make file helper diagnostics TAP-compatible - Validate read_num() input and propagate errors while restoring shared memory limits - Preserve build bisectability for the x86 protection_keys test - Preserve HugeTLB diagnostics using TAP-compatible printf() output - Validate the remaining numeric arguments accepted by gup_bench Changes in v4: - Address review feedback from Mike and Sashiko - Add a preparatory patch so shared file helpers return errors instead of exiting - Reduce include churn by keeping shared helpers exposed through vm_util.h - Preserve HugeTLB diagnostics and restore HugeTLB state more carefully - Fix selftests/mm build details after moving helpers to tools/lib/mm - Tighten gup_bench argument handling and gup_test setup/sparse-dump coverage 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 Changes in v2: - Address v1 feedback from Sashiko - Add fast and long-term 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 - Restore HugeTLB settings from fixture teardown - Report nr_pages_per_call for each iteration - Update the pin_user_pages unit-testing documentation Previous versions: v6: lore.kernel.org/all/[email protected]/ v5: lore.kernel.org/all/[email protected]/ v4: lore.kernel.org/all/[email protected]/ v3: lore.kernel.org/all/[email protected]/ v2: lore.kernel.org/all/[email protected]/ v1: lore.kernel.org/all/[email protected]/ --- Sarthak Sharma (6): selftests/mm: make file helpers return errors tools/lib/mm: add shared file helpers tools/lib/mm: move hugepage_settings out of selftests tools/mm: move gup_test from selftests/mm to tools/mm tools/mm: make gup_bench a benchmark only tool selftests/mm: add a GUP selftest Documentation/core-api/pin_user_pages.rst | 14 +- MAINTAINERS | 4 +- tools/lib/mm/file_utils.c | 104 ++++++ tools/lib/mm/file_utils.h | 13 + .../selftests => lib}/mm/hugepage_settings.c | 109 +++++- .../selftests => lib}/mm/hugepage_settings.h | 0 tools/mm/.gitignore | 1 + tools/mm/Makefile | 11 +- .../mm/gup_test.c => mm/gup_bench.c} | 194 +++++------ tools/testing/selftests/mm/Makefile | 15 +- tools/testing/selftests/mm/compaction_test.c | 2 +- tools/testing/selftests/mm/cow.c | 1 - .../selftests/mm/folio_split_race_test.c | 1 - tools/testing/selftests/mm/guard-regions.c | 1 - tools/testing/selftests/mm/gup.c | 329 ++++++++++++++++++ tools/testing/selftests/mm/gup_longterm.c | 1 - tools/testing/selftests/mm/hmm-tests.c | 6 +- tools/testing/selftests/mm/hugetlb-madvise.c | 1 - tools/testing/selftests/mm/hugetlb-mmap.c | 1 - tools/testing/selftests/mm/hugetlb-mremap.c | 1 - tools/testing/selftests/mm/hugetlb-shm.c | 1 - .../selftests/mm/hugetlb-soft-offline.c | 2 +- tools/testing/selftests/mm/hugetlb_dio.c | 1 - .../selftests/mm/hugetlb_fault_after_madv.c | 1 - .../selftests/mm/hugetlb_madv_vs_map.c | 1 - tools/testing/selftests/mm/khugepaged.c | 15 +- tools/testing/selftests/mm/ksm_tests.c | 1 - tools/testing/selftests/mm/migration.c | 2 +- tools/testing/selftests/mm/pagemap_ioctl.c | 1 - .../testing/selftests/mm/prctl_thp_disable.c | 1 - tools/testing/selftests/mm/protection_keys.c | 2 +- tools/testing/selftests/mm/run_vmtests.sh | 37 +- tools/testing/selftests/mm/soft-dirty.c | 1 - .../selftests/mm/split_huge_page_test.c | 6 +- tools/testing/selftests/mm/thuge-gen.c | 1 - tools/testing/selftests/mm/transhuge-stress.c | 1 - tools/testing/selftests/mm/uffd-common.h | 1 - tools/testing/selftests/mm/uffd-wp-mremap.c | 2 +- .../selftests/mm/va_high_addr_switch.c | 1 - tools/testing/selftests/mm/vm_util.c | 121 ++----- tools/testing/selftests/mm/vm_util.h | 8 +- 41 files changed, 710 insertions(+), 306 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 (87%) rename tools/{testing/selftests => lib}/mm/hugepage_settings.h (100%) rename tools/{testing/selftests/mm/gup_test.c => mm/gup_bench.c} (50%) create mode 100644 tools/testing/selftests/mm/gup.c base-commit: f9ca2fa9ef7e9b39ec79a0596929d1a1f8704c5f -- 2.39.5
