On 1 Mar 2024, at 8:09, Ryan Roberts wrote: > On 01/03/2024 12:52, Zi Yan wrote: >> On 1 Mar 2024, at 5:33, Ryan Roberts wrote: >> >>> On 01/03/2024 09:51, Aishwarya TCV wrote: >>>> >>>> >>>> On 26/02/2024 20:55, Zi Yan wrote: >>>>> From: Zi Yan <ziy@xxxxxxxxxx> >>>>> >>>>> It is used to test split_huge_page_to_list_to_order for pagecache THPs. >>>>> Also add test cases for split_huge_page_to_list_to_order via both >>>>> debugfs. >>>>> >>>>> Signed-off-by: Zi Yan <ziy@xxxxxxxxxx> >>>>> --- >>>>> mm/huge_memory.c | 34 ++++-- >>>>> .../selftests/mm/split_huge_page_test.c | 115 +++++++++++++++++- >>>>> 2 files changed, 131 insertions(+), 18 deletions(-) >>>>> >>>> >>>> Hi Zi, >>>> >>>> When booting the kernel against next-master(20240228)with Arm64 on >>>> Marvell Thunder X2 (TX2), the kselftest-mm test 'split_huge_page_test' >>>> is failing in our CI (with rootfs over NFS). I can send the full logs if >>>> required. >>> >>> Just to add, I took a quick eyeball and I think there a couple of potential issues: >>> >>> - In create_pagecache_thp_and_fd() you do *fd = open(testfile, O_CREAT ...); >>> where testfile is /mnt/thp_fs/testfile. So if /mnt/thp_fs doesn't exist, >>> then the open will fail I think? I'm pretty sure that's what's happening on >>> our CI. Suggest the test needs to setup this dir itself. Is thp_fs a mounted >>> fs or just a dir? If the latter can you just mktemp()? >> >> The former. the page cache folio split tests require a file system supporting >> large folio and I used XFS. > > OK got it. > >> >>> - Later in create_pagecache_thp_and_fd() you fail the test if you don't have a >>> filesystem that supports large folios. Can we turn that into a skip? That >>> would reduce noise on the CI. >> >> I can do that. But is this a new requirement that self tests have to be finish >> in CI/CD environment? Can you provide a guideline for it? > > I'm not sure what's written down, but certainly anyone should be able to run the > selftests with as little knowledge as possible, and they should only fail if > they detect a real problem. By convention a test should be skipped if the > environment (or kernel) isn't compatible. There are lots of examples of that in > mm selftests (just grep ksft_test_result_skip). mm selftests also has > run_vmtests.sh which does a lot of environment setup (e.g. reserving hugetlb > pages, etc) before actually running the tests. Got it. I will send a fixup to skip the page cache split test when the mount is not ready, then send a separate patch to set up XFS in run_vmtests.sh and pass it to this test. > >> Since I always assume >> selftests are just ran by human who can set up environment. > > I believe kernelci have been running mm skeftests on x86 for a long time. We > have started running them against arm64 on our CI for the last couple of months > and it had found a number of real issues in the kernel in -next, so this is > helping find and fix things early. So there is definitely benefit to keeping > these tests clean and robust. Got it. Make sense. > >> In addition, I do >> not think it is realistic to make the test file to set up all the environment, >> since everyone's machine is different. It is much easier to make the CI/CD >> environment to make the mount. > > That's reasonable, but then the requirements should be documented and you > probably would want to be able to optionally pass the mount on the command line. Will do. Thank you for the explanation. >>> >>> Thanks, >>> Ryan >>> >>>> >>>> A bisect (full log below) identified this patch as introducing the >>>> failure. Bisected it on the tag "next-20240228" at repo >>>> "https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git";. >>>> >>>> This works fine on Linux version 6.8.0-rc6 >>>> >>>> >>>> Sample log from failure against run on TX2: >>>> ------ >>>> 07:17:34.056125 # # ------------------------------ >>>> 07:17:34.056543 # # running ./split_huge_page_test >>>> 07:17:34.056839 # # ------------------------------ >>>> 07:17:34.057114 # # TAP version 13 >>>> 07:17:34.058564 # # 1..12 >>>> 07:17:34.156822 # # ok 1 Split huge pages successful >>>> 07:17:34.214074 # # ok 2 Split PTE-mapped huge pages successful >>>> 07:17:34.215630 # # # Please enable pr_debug in >>>> split_huge_pages_in_file() for more info. >>>> 07:17:34.225503 # # # Please check dmesg for more information >>>> 07:17:34.225862 # # ok 3 File-backed THP split test done >>>> 07:17:34.236944 # # Bail out! Failed to create a file at /mnt/thp_fs# >>>> Planned tests != run tests (12 != 3) >>>> 07:17:34.237307 # # # Totals: pass:3 fail:0 xfail:0 xpass:0 skip:0 error:0 >>>> 07:17:34.237620 # # [FAIL] >>>> 07:17:34.246430 # not ok 51 split_huge_page_test # exit=1 >>>> >>>> >>>> Bisect log: >>>> ------ >>>> git bisect start >>>> # good: [d206a76d7d2726f3b096037f2079ce0bd3ba329b] Linux 6.8-rc6 >>>> git bisect good d206a76d7d2726f3b096037f2079ce0bd3ba329b >>>> # bad: [20af1ca418d2c0b11bc2a1fe8c0c88f67bcc2a7e] Add linux-next >>>> specific files for 20240228 >>>> git bisect bad 20af1ca418d2c0b11bc2a1fe8c0c88f67bcc2a7e >>>> # bad: [1322f1801e59dddce10591d602d246c1bf49990c] Merge branch 'main' of >>>> git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git >>>> git bisect bad 1322f1801e59dddce10591d602d246c1bf49990c >>>> # bad: [a82f70041487790b7b09fe4bb45436e1b57021d3] Merge branch 'dev' of >>>> git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4.git >>>> git bisect bad a82f70041487790b7b09fe4bb45436e1b57021d3 >>>> # bad: [ce90480b9352ba2bebe8946dad9223e3f24c6e9a] Merge branch >>>> 'for-next' of >>>> git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap.git >>>> git bisect bad ce90480b9352ba2bebe8946dad9223e3f24c6e9a >>>> # bad: [5daac92ed3881fd0c656478a301a4e1d124100ee] Merge branch >>>> 'mm-everything' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm >>>> git bisect bad 5daac92ed3881fd0c656478a301a4e1d124100ee >>>> # good: [acc2643d9e988c63dd4629a9af380ad9ac69c54a] Merge branch >>>> 'mm-stable' into mm-unstable >>>> git bisect good acc2643d9e988c63dd4629a9af380ad9ac69c54a >>>> # good: [0294de8fe7d7c1a7eddc979cbf4c1886406e36b7] Merge branch 'fixes' >>>> of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply.git >>>> git bisect good 0294de8fe7d7c1a7eddc979cbf4c1886406e36b7 >>>> # good: [83e0c8f0e777a1ef0977b2f8189101765703b32d] Merge branch >>>> 'mm-nonmm-stable' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm >>>> git bisect good 83e0c8f0e777a1ef0977b2f8189101765703b32d >>>> # good: [a739cbe236e0dd3b6ff26a01fa1d31c73d4fac93] mm: memcg: make memcg >>>> huge page split support any order split >>>> git bisect good a739cbe236e0dd3b6ff26a01fa1d31c73d4fac93 >>>> # bad: [efb520aa333b2f11daaaaa13f4a598b5ae4ae823] mm: allow non-hugetlb >>>> large folios to be batch processed >>>> git bisect bad efb520aa333b2f11daaaaa13f4a598b5ae4ae823 >>>> # bad: [2258bdebb55e3ad3d30fd3849ddb955ff36825de] mm/zsmalloc: don't >>>> hold locks of all pages when free_zspage() >>>> git bisect bad 2258bdebb55e3ad3d30fd3849ddb955ff36825de >>>> # bad: [7fc0be45acf2878cbacc4dba56923c34c3fd8b1e] mm: remove >>>> total_mapcount() >>>> git bisect bad 7fc0be45acf2878cbacc4dba56923c34c3fd8b1e >>>> # good: [d55fac55da2f87ad5a99178e107df09770bbc411] mm: thp: split huge >>>> page to any lower order pages >>>> git bisect good d55fac55da2f87ad5a99178e107df09770bbc411 >>>> # bad: [4050d591c1aaf9336c08511fa5984827186e9ad1] mm/memfd: refactor >>>> memfd_tag_pins() and memfd_wait_for_pins() >>>> git bisect bad 4050d591c1aaf9336c08511fa5984827186e9ad1 >>>> # bad: [c0ba89c29ef559c95273feb481b049f622c43c17] mm: huge_memory: >>>> enable debugfs to split huge pages to any order >>>> git bisect bad c0ba89c29ef559c95273feb481b049f622c43c17 >>>> # first bad commit: [c0ba89c29ef559c95273feb481b049f622c43c17] mm: >>>> huge_memory: enable debugfs to split huge pages to any order >>>> >>>> >>>> Thanks, >>>> Aishwarya >> >> >> -- >> Best Regards, >> Yan, Zi -- Best Regards, Yan, Zi
Attachment:
signature.asc
Description: OpenPGP digital signature
