From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id CDF4C3E0081; Thu, 13 Aug 2026 18:13:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786644798; cv=none; b=sam5Mi5QdiAGXoXotHPW66sR7v0mLuMlyl6pkVH0Nd8zXKXk500KFhn47hVphuSsgDTk53b536nkGjDQOdW2LZs5lURXSH7TNMt4iwDR79zrCciNfX0ELT560rQZZOTULaxfAK8ZglRqaJPfmgpxhxc1NGAoZxoTiGRq7YIrGG4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786644798; c=relaxed/simple; bh=m1bGvj6UOubdng2fWNx+INIIJr6MJ9Bx14ljarArOwU=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=MvYYQzUlKC4lNUYUzAB7pyGi7GlF800z1QiV0XFkIMZCWYOUNnOPv4wtxcbSs2hYmPV1TIq7gF8rKZd231QOcWBzZFQ4snDFEjkLY1TI3bjHprffesKLw+C1/SRJ3ydyqvQ7eYnDzb2B7x3BMrtSz51VLqyyN/f4+vypBPXvmSQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=beP1j7Nn; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="beP1j7Nn" Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id DF99A1AC1; Thu, 13 Aug 2026 11:13:10 -0700 (PDT) Received: from a081061.arm.com (unknown [10.163.171.218]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id F0E8A3F66F; Thu, 13 Aug 2026 11:13:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1786644794; bh=m1bGvj6UOubdng2fWNx+INIIJr6MJ9Bx14ljarArOwU=; h=From:To:Cc:Subject:Date:From; b=beP1j7NnNYbW1T+TK0ZhpzJW+uBg/JNQpUbIZ4QR20EMSLzqX3iJ7UCCXHhLriOAN 0rBSRyaEklbpDBz+puBDl9ZHqL0kJH0EZka45AfFmDx8WlnPtltB0bECJUdyaaXMgc V6s9eDjGIKpA+dCL0+P7oBTYTQmmLjmhEg41C+Vk= From: Sarthak Sharma To: Andrew Morton , David Hildenbrand Cc: Lorenzo Stoakes , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Shuah Khan , Zi Yan , Baolin Wang , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Jason Gunthorpe , John Hubbard , Peter Xu , Leon Romanovsky , Jonathan Corbet , Shuah Khan , Mark Brown , Anshuman Khandual , linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Sarthak Sharma Subject: [PATCH v7 0/6] selftests/mm: separate GUP microbenchmarking from functional testing Date: Thu, 13 Aug 2026 23:42:24 +0530 Message-ID: <20260813181230.483746-1-sarthak.sharma@arm.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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/20260730140825.238130-1-sarthak.sharma@arm.com/ v5: lore.kernel.org/all/20260716123226.197736-1-sarthak.sharma@arm.com/ v4: lore.kernel.org/all/20260527142432.230127-1-sarthak.sharma@arm.com/ v3: lore.kernel.org/all/20260521111801.173019-1-sarthak.sharma@arm.com/ v2: lore.kernel.org/all/20260519120506.184512-1-sarthak.sharma@arm.com/ v1: lore.kernel.org/all/20260515084840.174652-1-sarthak.sharma@arm.com/ --- 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