From 9c84f229268fa229e250b7225611d0eb7094fea0 Mon Sep 17 00:00:00 2001 From: John Hubbard Date: Mon, 14 Dec 2020 19:05:05 -0800 Subject: mm/gup_benchmark: rename to mm/gup_test MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 --- mm/Kconfig | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) (limited to 'mm/Kconfig') diff --git a/mm/Kconfig b/mm/Kconfig index 390165ffbb0f..e25e5cb2989f 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -821,13 +821,18 @@ config PERCPU_STATS information includes global and per chunk statistics, which can be used to help understand percpu memory usage. -config GUP_BENCHMARK - bool "Enable infrastructure for get_user_pages() and related calls benchmarking" +config GUP_TEST + bool "Enable infrastructure for get_user_pages()-related unit tests" help - Provides /sys/kernel/debug/gup_benchmark that helps with testing - performance of get_user_pages() and related calls. + Provides /sys/kernel/debug/gup_test, which in turn provides a way + to make ioctl calls that can launch kernel-based unit tests for + the get_user_pages*() and pin_user_pages*() family of API calls. - See tools/testing/selftests/vm/gup_benchmark.c + These tests include benchmark testing of the _fast variants of + get_user_pages*() and pin_user_pages*(), as well as smoke tests of + the non-_fast variants. + + See tools/testing/selftests/vm/gup_test.c config GUP_GET_PTE_LOW_HIGH bool -- cgit From f4f9bda418ab8b4dbc5372e9e2a28162f7777154 Mon Sep 17 00:00:00 2001 From: John Hubbard Date: Mon, 14 Dec 2020 19:05:21 -0800 Subject: selftests/vm: gup_test: introduce the dump_pages() sub-test MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Cc: Jérôme Glisse Cc: Jonathan Corbet Cc: Ralph Campbell Cc: Shuah Khan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/Kconfig | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'mm/Kconfig') diff --git a/mm/Kconfig b/mm/Kconfig index e25e5cb2989f..350f2e23a94a 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -832,6 +832,12 @@ config GUP_TEST get_user_pages*() and pin_user_pages*(), as well as smoke tests of the non-_fast variants. + There is also a sub-test that allows running dump_page() on any + of up to eight pages (selected by command line args) within the + range of user-space addresses. These pages are either pinned via + pin_user_pages*(), or pinned via get_user_pages*(), as specified + by other command line arguments. + See tools/testing/selftests/vm/gup_test.c config GUP_GET_PTE_LOW_HIGH -- cgit From d0de82411864c4e1f24aaa3a653c7c08dd55c8d0 Mon Sep 17 00:00:00 2001 From: Barry Song Date: Mon, 14 Dec 2020 19:05:38 -0800 Subject: mm/gup_test: GUP_TEST depends on DEBUG_FS Without DEBUG_FS, all the code in gup_benchmark becomes meaningless. For sure kernel provides debugfs stub while DEBUG_FS is disabled, but the point here is that GUP_TEST can do nothing without DEBUG_FS. [song.bao.hua@hisilicon.com: add comment as a prompt to users as commented by John and Randy] Link: https://lkml.kernel.org/r/20201108083732.15336-1-song.bao.hua@hisilicon.com Link: https://lkml.kernel.org/r/20201104100552.20156-1-song.bao.hua@hisilicon.com Signed-off-by: Barry Song Suggested-by: John Garry Reviewed-by: John Hubbard Acked-by: Randy Dunlap Cc: Ralph Campbell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/Kconfig | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'mm/Kconfig') diff --git a/mm/Kconfig b/mm/Kconfig index 350f2e23a94a..5829d31649b9 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -823,6 +823,7 @@ config PERCPU_STATS config GUP_TEST bool "Enable infrastructure for get_user_pages()-related unit tests" + depends on DEBUG_FS help Provides /sys/kernel/debug/gup_test, which in turn provides a way to make ioctl calls that can launch kernel-based unit tests for @@ -840,6 +841,9 @@ config GUP_TEST See tools/testing/selftests/vm/gup_test.c +comment "GUP_TEST needs to have DEBUG_FS enabled" + depends on !GUP_TEST && !DEBUG_FS + config GUP_GET_PTE_LOW_HIGH bool -- cgit