linux-dev/tools/testing/selftests/vm/gup_benchmark.c, branch linus/master

mm/gup_benchmark: rename to mm/gup_test

2020-12-15T20:13:38Z

Patch series "selftests/vm: gup_test, hmm-tests, assorted improvements", v3. Summary: This series provides two main things, and a number of smaller supporting goodies. The two main points are: 1) Add a new sub-test to gup_test, which in turn is a renamed version of gup_benchmark. This sub-test allows nicer testing of dump_pages(), at least on user-space pages. For quite a while, I was doing a quick hack to gup_test.c whenever I wanted to try out changes to dump_page(). Then Matthew Wilcox asked me what I meant when I said "I used my dump_page() unit test", and I realized that it might be nice to check in a polished up version of that. Details about how it works and how to use it are in the commit description for patch #6 ("selftests/vm: gup_test: introduce the dump_pages() sub-test"). 2) Fixes a limitation of hmm-tests: these tests are incredibly useful, but only if people actually build and run them. And it turns out that libhugetlbfs is a little too effective at throwing a wrench in the works, there. So I've added a little configuration check that removes just two of the 21 hmm-tests, if libhugetlbfs is not available. Further details in the commit description of patch #8 ("selftests/vm: hmm-tests: remove the libhugetlbfs dependency"). Other smaller things that this series does: a) Remove code duplication by creating gup_test.h. b) Clear up the sub-test organization, and their invocation within run_vmtests.sh. c) Other minor assorted improvements. [1] v2 is here: https://lore.kernel.org/linux-doc/20200929212747.251804-1-jhubbard@nvidia.com/ [2] https://lore.kernel.org/r/CAHk-=wgh-TMPHLY3jueHX7Y2fWh3D+nMBqVS__AZm6-oorquWA@mail.gmail.com This patch (of 9): Rename nearly every "gup_benchmark" reference and file name to "gup_test". The one exception is for the actual gup benchmark test itself. The current code already does a *little* bit more than benchmarking, and definitely covers more than get_user_pages_fast(). More importantly, however, subsequent patches are about to add some functionality that is non-benchmark related. Closely related changes: * Kconfig: in addition to renaming the options from GUP_BENCHMARK to GUP_TEST, update the help text to reflect that it's no longer a benchmark-only test. Link: https://lkml.kernel.org/r/20201026064021.3545418-1-jhubbard@nvidia.com Link: https://lkml.kernel.org/r/20201026064021.3545418-2-jhubbard@nvidia.com Signed-off-by: John Hubbard Cc: Jonathan Corbet Cc: Jérôme Glisse Cc: Ralph Campbell Cc: Shuah Khan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge tag 'linux-kselftest-fixes-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

2020-10-14T21:23:51Z

Pull kselftest updates from Shuah Khan: - a selftests harness fix to flush stdout before forking to avoid parent and child printing duplicates messages. This is evident when test output is redirected to a file. - a tools/ wide change to avoid comma separated statements from Joe Perches. This fix spans tools/lib, tools/power/cpupower, and selftests. * tag 'linux-kselftest-fixes-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: tools: Avoid comma separated statements selftests/harness: Flush stdout before forking

mm/gup_benchmark: use pin_user_pages for FOLL_LONGTERM flag

2020-10-14T01:38:29Z

According to Documentation/core-api/pin_user_pages.rst, FOLL_PIN is a prerequisite to FOLL_LONGTERM. Another way of saying that is, FOLL_LONGTERM is a specific case, more restrictive case of FOLL_PIN. Almost all kernel modules are using pin_user_pages() with FOLL_LONGTERM, mm/gup_benchmark.c seems to the only exception in which FOLL_PIN is not a prerequisite to FOLL_LONGTERM. Signed-off-by: Barry Song Signed-off-by: Andrew Morton Reviewed-by: John Hubbard Cc: Jan Kara Cc: Jérôme Glisse Cc: "Matthew Wilcox (Oracle)" Cc: Al Viro Cc: Christoph Hellwig Cc: Dan Williams Cc: Dave Chinner Cc: Jason Gunthorpe Cc: Jonathan Corbet Cc: Michal Hocko Cc: Mike Kravetz Cc: Shuah Khan Cc: Vlastimil Babka Link: http://lkml.kernel.org/r/20200815122056.29508-1-song.bao.hua@hisilicon.com Signed-off-by: Linus Torvalds

tools: Avoid comma separated statements

2020-10-02T16:36:36Z

Use semicolons and braces. Signed-off-by: Joe Perches Signed-off-by: Shuah Khan

mm/gup_benchmark: support pin_user_pages() and related calls

2020-04-02T16:35:27Z

Up until now, gup_benchmark supported testing of the following kernel functions: * get_user_pages(): via the '-U' command line option * get_user_pages_longterm(): via the '-L' command line option * get_user_pages_fast(): as the default (no options required) Add test coverage for the new corresponding pin_*() functions: * pin_user_pages_fast(): via the '-a' command line option * pin_user_pages(): via the '-b' command line option Also, add an option for clarity: '-u' for what is now (still) the default choice: get_user_pages_fast(). Also, for the commands that set FOLL_PIN, verify that the pages really are dma-pinned, via the new is_dma_pinned() routine. Those commands are: PIN_FAST_BENCHMARK : calls pin_user_pages_fast() PIN_BENCHMARK : calls pin_user_pages() In between the calls to pin_*() and unpin_user_pages(), check each page: if page_maybe_dma_pinned() returns false, then WARN and return. Do this outside of the benchmark timestamps, so that it doesn't affect reported times. Signed-off-by: John Hubbard Signed-off-by: Andrew Morton Reviewed-by: Ira Weiny Acked-by: Kirill A. Shutemov Cc: Jan Kara Cc: Jérôme Glisse Cc: "Matthew Wilcox (Oracle)" Cc: Al Viro Cc: Christoph Hellwig Cc: Dan Williams Cc: Dave Chinner Cc: Jason Gunthorpe Cc: Jonathan Corbet Cc: Michal Hocko Cc: Mike Kravetz Cc: Shuah Khan Cc: Vlastimil Babka Link: http://lkml.kernel.org/r/20200211001536.1027652-10-jhubbard@nvidia.com Signed-off-by: Linus Torvalds

mm/gup_benchmark: use proper FOLL_WRITE flags instead of hard-coding "1"

2020-01-31T18:30:38Z

Fix the gup benchmark flags to use the symbolic FOLL_WRITE, instead of a hard-coded "1" value. Also, clean up the filtering of gup flags a little, by just doing it once before issuing any of the get_user_pages*() calls. This makes it harder to overlook, instead of having little "gup_flags & 1" phrases in the function calls. Link: http://lkml.kernel.org/r/20200107224558.2362728-22-jhubbard@nvidia.com Signed-off-by: John Hubbard Reviewed-by: Ira Weiny Cc: Alex Williamson Cc: Aneesh Kumar K.V Cc: Björn Töpel Cc: Christoph Hellwig Cc: Daniel Vetter Cc: Dan Williams Cc: Hans Verkuil Cc: Jan Kara Cc: Jason Gunthorpe Cc: Jason Gunthorpe Cc: Jens Axboe Cc: Jerome Glisse Cc: Jonathan Corbet Cc: Kirill A. Shutemov Cc: Leon Romanovsky Cc: Mauro Carvalho Chehab Cc: Mike Rapoport Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm/gup_benchmark: fix MAP_HUGETLB case

2019-11-06T16:28:58Z

The MAP_HUGETLB ("-H" option) of gup_benchmark fails: $ sudo ./gup_benchmark -H mmap: Invalid argument This is because gup_benchmark.c is passing in a file descriptor to mmap(), but the fd came from opening up the /dev/zero file. This confuses the mmap syscall implementation, which thinks that, if the caller did not specify MAP_ANONYMOUS, then the file must be a huge page file. So it attempts to verify that the file really is a huge page file, as you can see here: ksys_mmap_pgoff() { if (!(flags & MAP_ANONYMOUS)) { retval = -EINVAL; if (unlikely(flags & MAP_HUGETLB && !is_file_hugepages(file))) goto out_fput; /* THIS IS WHERE WE END UP */ else if (flags & MAP_HUGETLB) { ...proceed normally, /dev/zero is ok here... ...and of course is_file_hugepages() returns "false" for the /dev/zero file. The problem is that the user space program, gup_benchmark.c, really just wants anonymous memory here. The simplest way to get that is to pass MAP_ANONYMOUS whenever MAP_HUGETLB is specified, so that's what this patch does. Link: http://lkml.kernel.org/r/20191021212435.398153-2-jhubbard@nvidia.com Signed-off-by: John Hubbard Reviewed-by: Andrew Morton Reviewed-by: Jérôme Glisse Cc: Keith Busch Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm/gup_benchmark: add a missing "w" to getopt string

2019-10-19T10:32:32Z

Even though gup_benchmark.c has code to handle the -w command-line option, the "w" is not part of the getopt string. It looks as if it has been missing the whole time. On my machine, this leads naturally to the following predictable result: $ sudo ./gup_benchmark -w ./gup_benchmark: invalid option -- 'w' ...which is fixed with this commit. Link: http://lkml.kernel.org/r/20191014184639.1512873-2-jhubbard@nvidia.com Signed-off-by: John Hubbard Acked-by: Kirill A. Shutemov Cc: Keith Busch Cc: Shuah Khan Cc: Christoph Hellwig Cc: "Aneesh Kumar K . V" Cc: Ira Weiny Cc: Christoph Hellwig Cc: kbuild test robot Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

selftests/vm/gup_benchmark.c: match gup struct to kernel

2019-01-15T20:48:24Z

An expansion field was added to the kernel copy of this structure for future use. See mm/gup_benchmark.c. Add the same expansion field here, so that the IOCTL command decodes correctly. Otherwise, it fails with EINVAL. Signed-off-by: Alison Schofield Acked-by: Kirill A. Shutemov Signed-off-by: Shuah Khan

tools/testing/selftests/vm/gup_benchmark.c: add MAP_HUGETLB option

2018-10-26T23:38:15Z

Add a new option '-H' to the gup benchmark to help understand how hugetlb mapping pages compare with the default. Link: http://lkml.kernel.org/r/20181010195605.10689-6-keith.busch@intel.com Signed-off-by: Keith Busch Reviewed-by: Andrew Morton Cc: Kirill Shutemov Cc: Dave Hansen Cc: Dan Williams Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds