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2023-06-23Merge mm-hotfixes-stable into mm-stable to pick up depended-upon changes.Andrew Morton
2023-06-19mm/gup_test.c: convert verify_dma_pinned() to us foliosVishal Moola (Oracle)
verify_dma_pinned() checks that pages are dma-pinned. We can convert this to use folios. Link: https://lkml.kernel.org/r/20230614021312.34085-4-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Lorenzo Stoakes <lstoakes@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-12mm/gup_test: fix ioctl fail for compat taskHaibo Li
When tools/testing/selftests/mm/gup_test.c is compiled as 32bit, then run on arm64 kernel, it reports "ioctl: Inappropriate ioctl for device". Fix it by filling compat_ioctl in gup_test_fops Link: https://lkml.kernel.org/r/20230526022125.175728-1-haibo.li@mediatek.com Signed-off-by: Haibo Li <haibo.li@mediatek.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09mm/gup: remove vmas parameter from pin_user_pages()Lorenzo Stoakes
We are now in a position where no caller of pin_user_pages() requires the vmas parameter at all, so eliminate this parameter from the function and all callers. This clears the way to removing the vmas parameter from GUP altogether. Link: https://lkml.kernel.org/r/195a99ae949c9f5cb589d2222b736ced96ec199a.1684350871.git.lstoakes@gmail.com Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com> [qib] Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com> [drivers/media] Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian König <christian.koenig@amd.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Janosch Frank <frankja@linux.ibm.com> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Sean Christopherson <seanjc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09mm/gup: remove unused vmas parameter from get_user_pages()Lorenzo Stoakes
Patch series "remove the vmas parameter from GUP APIs", v6. (pin_/get)_user_pages[_remote]() each provide an optional output parameter for an array of VMA objects associated with each page in the input range. These provide the means for VMAs to be returned, as long as mm->mmap_lock is never released during the GUP operation (i.e. the internal flag FOLL_UNLOCKABLE is not specified). In addition, these VMAs can only be accessed with the mmap_lock held and become invalidated the moment it is released. The vast majority of invocations do not use this functionality and of those that do, all but one case retrieve a single VMA to perform checks upon. It is not egregious in the single VMA cases to simply replace the operation with a vma_lookup(). In these cases we duplicate the (fast) lookup on a slow path already under the mmap_lock, abstracted to a new get_user_page_vma_remote() inline helper function which also performs error checking and reference count maintenance. The special case is io_uring, where io_pin_pages() specifically needs to assert that the VMAs underlying the range do not result in broken long-term GUP file-backed mappings. As GUP now internally asserts that FOLL_LONGTERM mappings are not file-backed in a broken fashion (i.e. requiring dirty tracking) - as implemented in "mm/gup: disallow FOLL_LONGTERM GUP-nonfast writing to file-backed mappings" - this logic is no longer required and so we can simply remove it altogether from io_uring. Eliminating the vmas parameter eliminates an entire class of danging pointer errors that might have occured should the lock have been incorrectly released. In addition, the API is simplified and now clearly expresses what it is intended for - applying the specified GUP flags and (if pinning) returning pinned pages. This change additionally opens the door to further potential improvements in GUP and the possible marrying of disparate code paths. I have run this series against gup_test with no issues. Thanks to Matthew Wilcox for suggesting this refactoring! This patch (of 6): No invocation of get_user_pages() use the vmas parameter, so remove it. The GUP API is confusing and caveated. Recent changes have done much to improve that, however there is more we can do. Exporting vmas is a prime target as the caller has to be extremely careful to preclude their use after the mmap_lock has expired or otherwise be left with dangling pointers. Removing the vmas parameter focuses the GUP functions upon their primary purpose - pinning (and outputting) pages as well as performing the actions implied by the input flags. This is part of a patch series aiming to remove the vmas parameter altogether. Link: https://lkml.kernel.org/r/cover.1684350871.git.lstoakes@gmail.com Link: https://lkml.kernel.org/r/589e0c64794668ffc799651e8d85e703262b1e9d.1684350871.git.lstoakes@gmail.com Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Suggested-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Acked-by: Christian König <christian.koenig@amd.com> (for radeon parts) Acked-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Sean Christopherson <seanjc@google.com> (KVM) Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com> Cc: Janosch Frank <frankja@linux.ibm.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-12-15mm/gup_test: free memory allocated via kvcalloc() using kvfree()David Hildenbrand
We have to free via kvfree(), not via kfree(). Link: https://lkml.kernel.org/r/20221212182018.264900-1-david@redhat.com Fixes: c77369b437f9 ("mm/gup_test: start/stop/read functionality for PIN LONGTERM test") Signed-off-by: David Hildenbrand <david@redhat.com> Reported-by: kernel test robot <lkp@intel.com> Reported-by: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-12-11mm/gup_test: fix PIN_LONGTERM_TEST_READ with highmemDavid Hildenbrand
Patch series "selftests/vm: fix some tests on 32bit". I finally had the time to run some of the selftests written by me (especially "cow") on x86 PAE. I found some unexpected "surprises" :) With these changes, and with [1] on top of mm-unstable, the "cow" tests and the "ksm_functional_tests" compile and pass as expected (expected failures with hugetlb in the "cow" tests). "madv_populate" has one expected test failure -- x86 does not support softdirty tracking. #1-#3 fix commits with stable commit ids. #4 fixes a test that is not in mm-stable yet. A note that there are many other compile errors/warnings when compiling on 32bit and with older Linux headers ... something for another day. [1] https://lkml.kernel.org/r/20221205150857.167583-1-david@redhat.com This patch (of 4): ... we have to kmap()/kunmap(), otherwise this won't work as expected with highmem. Link: https://lkml.kernel.org/r/20221205193716.276024-1-david@redhat.com Link: https://lkml.kernel.org/r/20221205193716.276024-2-david@redhat.com Fixes: c77369b437f9 ("mm/gup_test: start/stop/read functionality for PIN LONGTERM test") Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Shuah Khan <shuah@kernel.org>, Cc: Yang Li <yang.lee@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-08mm/gup_test: start/stop/read functionality for PIN LONGTERM testDavid Hildenbrand
We want an easy way to take a R/O or R/W longterm pin on a range and be able to observe the content of the pinned pages, so we can properly test how longterm puns interact with our COW logic. [david@redhat.com: silence a warning on 32-bit] Link: https://lkml.kernel.org/r/74adbb51-6e33-f636-8a9c-2ad87bd9007e@redhat.com [yang.lee@linux.alibaba.com: ./mm/gup_test.c:281:2-3: Unneeded semicolon] Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=2455 Link: https://lkml.kernel.org/r/20221020024035.113619-1-yang.lee@linux.alibaba.com Link: https://lkml.kernel.org/r/20220927110120.106906-7-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Yang Li <yang.lee@linux.alibaba.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Christoph von Recklinghausen <crecklin@redhat.com> Cc: Don Dutile <ddutile@redhat.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Nadav Amit <namit@vmware.com> Cc: Peter Xu <peterx@redhat.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-17mm: rename is_pinnable_page() to is_longterm_pinnable_page()Alex Sierra
Patch series "Add MEMORY_DEVICE_COHERENT for coherent device memory mapping", v9. This patch series introduces MEMORY_DEVICE_COHERENT, a type of memory owned by a device that can be mapped into CPU page tables like MEMORY_DEVICE_GENERIC and can also be migrated like MEMORY_DEVICE_PRIVATE. This patch series is mostly self-contained except for a few places where it needs to update other subsystems to handle the new memory type. System stability and performance are not affected according to our ongoing testing, including xfstests. How it works: The system BIOS advertises the GPU device memory (aka VRAM) as SPM (special purpose memory) in the UEFI system address map. The amdgpu driver registers the memory with devmap as MEMORY_DEVICE_COHERENT using devm_memremap_pages. The initial user for this hardware page migration capability is the Frontier supercomputer project. This functionality is not AMD-specific. We expect other GPU vendors to find this functionality useful, and possibly other hardware types in the future. Our test nodes in the lab are similar to the Frontier configuration, with .5 TB of system memory plus 256 GB of device memory split across 4 GPUs, all in a single coherent address space. Page migration is expected to improve application efficiency significantly. We will report empirical results as they become available. Coherent device type pages at gup are now migrated back to system memory if they are being pinned long-term (FOLL_LONGTERM). The reason is, that long-term pinning would interfere with the device memory manager owning the device-coherent pages (e.g. evictions in TTM). These series incorporate Alistair Popple patches to do this migration from pin_user_pages() calls. hmm_gup_test has been added to hmm-test to test different get user pages calls. This series includes handling of device-managed anonymous pages returned by vm_normal_pages. Although they behave like normal pages for purposes of mapping in CPU page tables and for COW, they do not support LRU lists, NUMA migration or THP. We also introduced a FOLL_LRU flag that adds the same behaviour to follow_page and related APIs, to allow callers to specify that they expect to put pages on an LRU list. This patch (of 14): is_pinnable_page() and folio_is_pinnable() are renamed to is_longterm_pinnable_page() and folio_is_longterm_pinnable() respectively. These functions are used in the FOLL_LONGTERM flag context. Link: https://lkml.kernel.org/r/20220715150521.18165-1-alex.sierra@amd.com Link: https://lkml.kernel.org/r/20220715150521.18165-2-alex.sierra@amd.com Signed-off-by: Alex Sierra <alex.sierra@amd.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Felix Kuehling <Felix.Kuehling@amd.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2021-05-05selftests/vm: gup_test: test faulting in kernel, and verify pinnable pagesPavel Tatashin
When pages are pinned they can be faulted in userland and migrated, and they can be faulted right in kernel without migration. In either case, the pinned pages must end-up being pinnable (not movable). Add a new test to gup_test, to help verify that the gup/pup (get_user_pages() / pin_user_pages()) behavior with respect to pinnable and movable pages is reasonable and correct. Specifically, provide a way to: 1) Verify that only "pinnable" pages are pinned. This is checked automatically for you. 2) Verify that gup/pup performance is reasonable. This requires comparing benchmarks between doing gup/pup on pages that have been pre-faulted in from user space, vs. doing gup/pup on pages that are not faulted in until gup/pup time (via FOLL_TOUCH). This decision is controlled with the new -z command line option. Link: https://lkml.kernel.org/r/20210215161349.246722-15-pasha.tatashin@soleen.com Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: James Morris <jmorris@namei.org> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sasha Levin <sashal@kernel.org> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Tyler Hicks <tyhicks@linux.microsoft.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-05selftests/vm: gup_test: fix test flagPavel Tatashin
In gup_test both gup_flags and test_flags use the same flags field. This is broken. Farther, in the actual gup_test.c all the passed gup_flags are erased and unconditionally replaced with FOLL_WRITE. Which means that test_flags are ignored, and code like this always performs pin dump test: 155 if (gup->flags & GUP_TEST_FLAG_DUMP_PAGES_USE_PIN) 156 nr = pin_user_pages(addr, nr, gup->flags, 157 pages + i, NULL); 158 else 159 nr = get_user_pages(addr, nr, gup->flags, 160 pages + i, NULL); 161 break; Add a new test_flags field, to allow raw gup_flags to work. Add a new subcommand for DUMP_USER_PAGES_TEST to specify that pin test should be performed. Remove unconditional overwriting of gup_flags via FOLL_WRITE. But, preserve the previous behaviour where FOLL_WRITE was the default flag, and add a new option "-W" to unset FOLL_WRITE. Rename flags with gup_flags. With the fix, dump works like this: root@virtme:/# gup_test -c ---- page #0, starting from user virt addr: 0x7f8acb9e4000 page:00000000d3d2ee27 refcount:2 mapcount:1 mapping:0000000000000000 index:0x0 pfn:0x100bcf anon flags: 0x300000000080016(referenced|uptodate|lru|swapbacked) raw: 0300000000080016 ffffd0e204021608 ffffd0e208df2e88 ffff8ea04243ec61 raw: 0000000000000000 0000000000000000 0000000200000000 0000000000000000 page dumped because: gup_test: dump_pages() test DUMP_USER_PAGES_TEST: done root@virtme:/# gup_test -c -p ---- page #0, starting from user virt addr: 0x7fd19701b000 page:00000000baed3c7d refcount:1025 mapcount:1 mapping:0000000000000000 index:0x0 pfn:0x108008 anon flags: 0x300000000080014(uptodate|lru|swapbacked) raw: 0300000000080014 ffffd0e204200188 ffffd0e205e09088 ffff8ea04243ee71 raw: 0000000000000000 0000000000000000 0000040100000000 0000000000000000 page dumped because: gup_test: dump_pages() test DUMP_USER_PAGES_TEST: done Refcount shows the difference between pin vs no-pin case. Also change type of nr from int to long, as it counts number of pages. Link: https://lkml.kernel.org/r/20210215161349.246722-14-pasha.tatashin@soleen.com Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: James Morris <jmorris@namei.org> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sasha Levin <sashal@kernel.org> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Tyler Hicks <tyhicks@linux.microsoft.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15mm/gup_test.c: mark gup_test_init as __init functionBarry Song
gup_test_init() is only called during initialization, mark it as __init to save some memory. Link: https://lkml.kernel.org/r/20201103081016.16532-1-song.bao.hua@hisilicon.com Signed-off-by: Barry Song <song.bao.hua@hisilicon.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15selftests/vm: gup_test: introduce the dump_pages() sub-testJohn Hubbard
For quite a while, I was doing a quick hack to gup_test.c (previously, gup_benchmark.c) whenever I wanted to try out my changes to dump_page(). This makes that hack unnecessary, and instead allows anyone to easily get the same coverage from a user space program. That saves a lot of time because you don't have to change the kernel, in order to test different pages and options. The new sub-test takes advantage of the existing gup_test infrastructure, which already provides a simple user space program, some allocated user space pages, an ioctl call, pinning of those pages (via either get_user_pages or pin_user_pages) and a corresponding kernel-side test invocation. There's not much more required, mainly just a couple of inputs from the user. In fact, the new test re-uses the existing command line options in order to get various helpful combinations (THP or normal, _fast or slow gup, gup vs. pup, and more). New command line options are: which pages to dump, and what type of "get/pin" to use. In order to figure out which pages to dump, the logic is: * If the user doesn't specify anything, the page 0 (the first page in the address range that the program sets up for testing) is dumped. * Or, the user can type up to 8 page indices anywhere on the command line. If you type more than 8, then it uses the first 8 and ignores the remaining items. For example: ./gup_test -ct -F 1 0 19 0x1000 Meaning: -c: dump pages sub-test -t: use THP pages -F 1: use pin_user_pages() instead of get_user_pages() 0 19 0x1000: dump pages 0, 19, and 4096 Link: https://lkml.kernel.org/r/20201026064021.3545418-7-jhubbard@nvidia.com Signed-off-by: John Hubbard <jhubbard@nvidia.com> Cc: Jérôme Glisse <jglisse@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15selftests/vm: only some gup_test items are really benchmarksJohn Hubbard
Therefore, some minor cleanup and improvements are in order: 1. Rename the other items appropriately. 2. Stop reporting timing information on the non-benchmark items. It's still being recorded and is available, but there's no point in cluttering up the report with data that no one reasonably needs to check. 3. Don't do iterations, for non-benchmark items. 4. Print out a shorter, more appropriate report for the non-benchmark tests. 5. Add the command that was run, to the report. This really helps, as there are quite a lot of options now. 6. Use a larger integer type for cmd, now that it's being compared Otherwise it doesn't work, because in this case cmd is about 3 billion, which is the perfect size for problems with signed vs unsigned int. Link: https://lkml.kernel.org/r/20201026064021.3545418-6-jhubbard@nvidia.com Signed-off-by: John Hubbard <jhubbard@nvidia.com> Cc: Jérôme Glisse <jglisse@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15selftests/vm: use a common gup_test.hJohn Hubbard
Avoid the need to copy-paste the gup_test ioctl commands and the struct gup_test definition, between the kernel and the user space application, by providing a new header file for these. This allows easier and safer adding of new ioctl calls, as well as reducing the overall line count. Details: The header file has to be able to compile independently, because of the arguably unfortunate way that the Makefile is written: the Makefile tries to build all of its prerequisites, when really it should be only building the .c files, and leaving the other prerequisites (LOCAL_HDRS) as pure dependencies. That Makefile limitation is probably not worth fixing, but it explains why one of the includes had to be moved into the new header file. Also: simplify the ioctl struct (struct gup_test), by deleting the unused __expansion[10] field. This sort of thing is what you might see in a stable ABI, but this low-level, kernel-developer-oriented selftests/vm system is very much not subject to ABI stability. So "expansion" and "reserved" fields are unnecessary here. Link: https://lkml.kernel.org/r/20201026064021.3545418-3-jhubbard@nvidia.com Signed-off-by: John Hubbard <jhubbard@nvidia.com> Cc: Jérôme Glisse <jglisse@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15mm/gup_benchmark: rename to mm/gup_testJohn Hubbard
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 <jhubbard@nvidia.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jérôme Glisse <jglisse@redhat.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>