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2020-10-13mm/page_isolation: drop WARN_ON_ONCE() in set_migratetype_isolate()Gravatar David Hildenbrand 1-9/+6
Inside has_unmovable_pages(), we have a comment describing how unmovable data could end up in ZONE_MOVABLE - via "movablecore". Also, besides checking if the first page in the pageblock is reserved, we don't perform any further checks in case of ZONE_MOVABLE. In case of memory offlining, we set REPORT_FAILURE, properly dump_page() the page and handle the error gracefully. alloc_contig_pages() users currently never allocate from ZONE_MOVABLE. E.g., hugetlb uses alloc_contig_pages() for the allocation of gigantic pages only, which will never end up on the MOVABLE zone (see htlb_alloc_mask()). Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Baoquan He <bhe@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Qian Cai <cai@lca.pw> Link: http://lkml.kernel.org/r/20200816125333.7434-4-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/page_isolation: exit early when pageblock is isolated in ↵Gravatar David Hildenbrand 1-4/+5
set_migratetype_isolate() Right now, if we have two isolations racing on a pageblock that's in the MOVABLE zone, we would trigger the WARN_ON_ONCE(). Let's just return directly, simplifying error handling. The change was introduced in commit 3d680bdf60a5 ("mm/page_isolation: fix potential warning from user"). As far as I can see, we currently don't have alloc_contig_range() users that use the ZONE_MOVABLE (anymore), so it's currently more a cleanup and a preparation for the future than a fix. Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Baoquan He <bhe@redhat.com> Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Acked-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Qian Cai <cai@lca.pw> Cc: Jason Wang <jasowang@redhat.com> Cc: Mike Rapoport <rppt@kernel.org> Link: http://lkml.kernel.org/r/20200816125333.7434-3-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/page_alloc: tweak comments in has_unmovable_pages()Gravatar David Hildenbrand 1-16/+6
Patch series "mm / virtio-mem: support ZONE_MOVABLE", v5. When introducing virtio-mem, the semantics of ZONE_MOVABLE were rather unclear, which is why we special-cased ZONE_MOVABLE such that partially plugged blocks would never end up in ZONE_MOVABLE. Now that the semantics are much clearer (and are documented in patch #6), let's support partially plugged memory blocks in ZONE_MOVABLE, allowing partially plugged memory blocks to be online to ZONE_MOVABLE and also unplugging from such memory blocks. This avoids surprises when onlining of memory blocks suddenly fails, just because they are not completely populated by virtio-mem (yet). This is especially helpful for testing, but also paves the way for virtio-mem optimizations, allowing more memory to get reliably unplugged. Cleanup has_unmovable_pages() and set_migratetype_isolate(), providing better documentation of how ZONE_MOVABLE interacts with different kind of unmovable pages (memory offlining vs. alloc_contig_range()). This patch (of 6): Let's move the split comment regarding bootmem allocations and memory holes, especially in the context of ZONE_MOVABLE, to the PageReserved() check. Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Baoquan He <bhe@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Qian Cai <cai@lca.pw> Link: http://lkml.kernel.org/r/20200816125333.7434-1-david@redhat.com Link: http://lkml.kernel.org/r/20200816125333.7434-2-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm: kasan: do not panic if both panic_on_warn and kasan_multishot setGravatar David Gow 1-1/+1
KASAN errors will currently trigger a panic when panic_on_warn is set. This renders kasan_multishot useless, as further KASAN errors won't be reported if the kernel has already paniced. By making kasan_multishot disable this behaviour for KASAN errors, we can still have the benefits of panic_on_warn for non-KASAN warnings, yet be able to use kasan_multishot. This is particularly important when running KASAN tests, which need to trigger multiple KASAN errors: previously these would panic the system if panic_on_warn was set, now they can run (and will panic the system should non-KASAN warnings show up). Signed-off-by: David Gow <davidgow@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Patricia Alfonso <trishalfonso@google.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Shuah Khan <shuah@kernel.org> Cc: Vincent Guittot <vincent.guittot@linaro.org> Link: https://lkml.kernel.org/r/20200915035828.570483-6-davidgow@google.com Link: https://lkml.kernel.org/r/20200910070331.3358048-6-davidgow@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13KASAN: Testing DocumentationGravatar Patricia Alfonso 1-0/+70
Include documentation on how to test KASAN using CONFIG_TEST_KASAN_KUNIT and CONFIG_TEST_KASAN_MODULE. Signed-off-by: Patricia Alfonso <trishalfonso@google.com> Signed-off-by: David Gow <davidgow@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Acked-by: Brendan Higgins <brendanhiggins@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Shuah Khan <shuah@kernel.org> Cc: Vincent Guittot <vincent.guittot@linaro.org> Link: https://lkml.kernel.org/r/20200915035828.570483-5-davidgow@google.com Link: https://lkml.kernel.org/r/20200910070331.3358048-5-davidgow@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13KASAN: port KASAN Tests to KUnitGravatar Patricia Alfonso 4-438/+386
Transfer all previous tests for KASAN to KUnit so they can be run more easily. Using kunit_tool, developers can run these tests with their other KUnit tests and see "pass" or "fail" with the appropriate KASAN report instead of needing to parse each KASAN report to test KASAN functionalities. All KASAN reports are still printed to dmesg. Stack tests do not work properly when KASAN_STACK is enabled so those tests use a check for "if IS_ENABLED(CONFIG_KASAN_STACK)" so they only run if stack instrumentation is enabled. If KASAN_STACK is not enabled, KUnit will print a statement to let the user know this test was not run with KASAN_STACK enabled. copy_user_test and kasan_rcu_uaf cannot be run in KUnit so there is a separate test file for those tests, which can be run as before as a module. [trishalfonso@google.com: v14] Link: https://lkml.kernel.org/r/20200915035828.570483-4-davidgow@google.com Signed-off-by: Patricia Alfonso <trishalfonso@google.com> Signed-off-by: David Gow <davidgow@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Reviewed-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Shuah Khan <shuah@kernel.org> Cc: Vincent Guittot <vincent.guittot@linaro.org> Link: https://lkml.kernel.org/r/20200910070331.3358048-4-davidgow@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13KUnit: KASAN IntegrationGravatar Patricia Alfonso 5-7/+96
Integrate KASAN into KUnit testing framework. - Fail tests when KASAN reports an error that is not expected - Use KUNIT_EXPECT_KASAN_FAIL to expect a KASAN error in KASAN tests - Expected KASAN reports pass tests and are still printed when run without kunit_tool (kunit_tool still bypasses the report due to the test passing) - KUnit struct in current task used to keep track of the current test from KASAN code Make use of "[PATCH v3 kunit-next 1/2] kunit: generalize kunit_resource API beyond allocated resources" and "[PATCH v3 kunit-next 2/2] kunit: add support for named resources" from Alan Maguire [1] - A named resource is added to a test when a KASAN report is expected - This resource contains a struct for kasan_data containing booleans representing if a KASAN report is expected and if a KASAN report is found [1] (https://lore.kernel.org/linux-kselftest/1583251361-12748-1-git-send-email-alan.maguire@oracle.com/T/#t) Signed-off-by: Patricia Alfonso <trishalfonso@google.com> Signed-off-by: David Gow <davidgow@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Acked-by: Brendan Higgins <brendanhiggins@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Shuah Khan <shuah@kernel.org> Cc: Vincent Guittot <vincent.guittot@linaro.org> Link: https://lkml.kernel.org/r/20200915035828.570483-3-davidgow@google.com Link: https://lkml.kernel.org/r/20200910070331.3358048-3-davidgow@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13kasan/kunit: add KUnit Struct to Current TaskGravatar Patricia Alfonso 1-0/+4
Patch series "KASAN-KUnit Integration", v14. This patchset contains everything needed to integrate KASAN and KUnit. KUnit will be able to: (1) Fail tests when an unexpected KASAN error occurs (2) Pass tests when an expected KASAN error occurs Convert KASAN tests to KUnit with the exception of copy_user_test because KUnit is unable to test those. Add documentation on how to run the KASAN tests with KUnit and what to expect when running these tests. This patch (of 5): In order to integrate debugging tools like KASAN into the KUnit framework, add KUnit struct to the current task to keep track of the current KUnit test. Signed-off-by: Patricia Alfonso <trishalfonso@google.com> Signed-off-by: David Gow <davidgow@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Cc: Brendan Higgins <brendanhiggins@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: Shuah Khan <shuah@kernel.org> Link: https://lkml.kernel.org/r/20200915035828.570483-1-davidgow@google.com Link: https://lkml.kernel.org/r/20200915035828.570483-2-davidgow@google.com Link: https://lkml.kernel.org/r/20200910070331.3358048-1-davidgow@google.com Link: https://lkml.kernel.org/r/20200910070331.3358048-2-davidgow@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13docs/vm: fix 'mm_count' vs 'mm_users' counter confusionGravatar Alexander Gordeev 1-1/+1
In the context of the anonymous address space lifespan description the 'mm_users' reference counter is confused with 'mm_count'. I.e a "zombie" mm gets released when "mm_count" becomes zero, not "mm_users". Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Jonathan Corbet <corbet@lwn.net> Link: https://lkml.kernel.org/r/1597040695-32633-1-git-send-email-agordeev@linux.ibm.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/vmalloc.c: fix the comment of find_vm_areaGravatar Hui Su 1-2/+2
Fix the comment of find_vm_area() and get_vm_area() Signed-off-by: Hui Su <sh_def@163.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Link: https://lkml.kernel.org/r/20200927153034.GA199877@rlk Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/vmalloc.c: update the comment in __vmalloc_area_node()Gravatar Hui Su 1-1/+1
Since c67dc624757 ("mm/vmalloc: do not call kmemleak_free() on not yet accounted memory"), the __vunmap() have been changed to __vfree(), so update the confusing comment(). Signed-off-by: Hui Su <sh_def@163.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Roman Penyaev <rpenyaev@suse.de> Link: https://lkml.kernel.org/r/20200927155409.GA3315@rlk Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/memory-failure.c: remove unused macro `writeback'Gravatar Alex Shi 1-2/+0
Unlike others we don't use the marco writeback. so let's remove it to tame gcc warning: mm/memory-failure.c:827: warning: macro "writeback" is not used [-Wunused-macros] Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Naoya Horiguchi <naoya.horiguchi@nec.com> Link: https://lkml.kernel.org/r/1599715096-20369-1-git-send-email-alex.shi@linux.alibaba.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/memory-failure: do pgoff calculation before for_each_process()Gravatar Xianting Tian 1-1/+2
There is no need to calculate pgoff in each loop of for_each_process(), so move it to the place before for_each_process(), which can save some CPU cycles. Signed-off-by: Xianting Tian <tian.xianting@h3c.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com> Link: http://lkml.kernel.org/r/20200818082647.34322-1-tian.xianting@h3c.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/dmapool.c: replace hard coded function name with __func__Gravatar Andy Shevchenko 1-22/+18
No need to hard code function name when __func__ can be used. While here, replace specifiers for special types like dma_addr_t. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Matthew Wilcox <willy@infradead.org> Link: http://lkml.kernel.org/r/20200814135055.24898-2-andriy.shevchenko@linux.intel.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/dmapool.c: replace open-coded list_for_each_entry_safe()Gravatar Andy Shevchenko 1-4/+2
There is a place in the code where open-coded version of list_for_each_entry_safe() is used. Replace that with the standard macro. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Matthew Wilcox <willy@infradead.org> Link: http://lkml.kernel.org/r/20200814135055.24898-1-andriy.shevchenko@linux.intel.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13lib/test_hmm.c: remove unused dmirror_zero_pageGravatar Ralph Campbell 1-14/+0
The variable dmirror_zero_page is unused in the HMM self test driver which was probably intended to demonstrate how a driver could use migrate_vma_setup() to share a single read-only device private zero page similar to how the CPU does. However, this isn't needed for the self tests so remove it. Signed-off-by: Ralph Campbell <rcampbell@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Jerome Glisse <jglisse@redhat.com> Link: https://lkml.kernel.org/r/20200914213801.16520-1-rcampbell@nvidia.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13tools/testing/selftests/vm/hmm-tests.c: use the new SKIP() macroGravatar Ralph Campbell 1-2/+2
Some tests might not be able to be run if resources like huge pages are not available. Mark these tests as skipped instead of simply passing. Signed-off-by: Ralph Campbell <rcampbell@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Shuah Khan <shuah@kernel.org> Link: http://lkml.kernel.org/r/20200827190400.12608-1-rcampbell@nvidia.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13include/linux/huge_mm.h: remove mincore_huge_pmd declarationGravatar yuleixzhang 1-3/+0
As mincore_huge_pmd() was dropped, remove the declaration from the header file. Signed-off-by: Yulei Zhang <yuleixzhang@tencent.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Zi Yan <ziy@nvidia.com> Link: https://lkml.kernel.org/r/20200922083423.15074-1-yuleixzhang@tencent.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm: remove src/dst mm parameter in copy_page_range()Gravatar Peter Xu 3-71/+76
Both of the mm pointers are not needed after commit 7a4830c380f3 ("mm/fork: Pass new vma pointer into copy_page_range()"). Jason Gunthorpe also reported that the ordering of copy_page_range() is odd. Since working at it, reorder the parameters to be logical, by (1) always put the dst_* fields to be before src_* fields, and (2) keep the same type of parameters together. [peterx@redhat.com: further reorder some parameters and line format, per Jason] Link: https://lkml.kernel.org/r/20201002192647.7161-1-peterx@redhat.com [peterx@redhat.com: fix warnings] Link: https://lkml.kernel.org/r/20201006200138.GA6026@xz-x1 Reported-by: Kirill A. Shutemov <kirill@shutemov.name> Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Link: https://lkml.kernel.org/r/20200930204950.6668-1-peterx@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/mmap.c: replace do_brk with do_brk_flags in comment of insert_vm_struct()Gravatar Liao Pingfang 1-1/+1
Replace do_brk with do_brk_flags in comment of insert_vm_struct(), since do_brk was removed in following commit. Fixes: bb177a732c4369 ("mm: do not bug_on on incorrect length in __mm_populate()") Signed-off-by: Liao Pingfang <liao.pingfang@zte.com.cn> Signed-off-by: Yi Wang <wang.yi59@zte.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Link: https://lkml.kernel.org/r/1600650778-43230-1-git-send-email-wang.yi59@zte.com.cn Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/mmap.c: use helper function allow_write_access() in ↵Gravatar Miaohe Lin 1-1/+1
__remove_shared_vm_struct() In commit 1da177e4c3f4 ("Linux-2.6.12-rc2"), the helper allow_write_access came with the atomic_inc operation of the i_writecount field in the func __remove_shared_vm_struct(). But it forgot to use this helper function. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Link: https://lkml.kernel.org/r/20200921115814.39680-1-linmiaohe@huawei.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm: use helper function mapping_allow_writable()Gravatar Miaohe Lin 2-2/+2
Commit 4bb5f5d9395b ("mm: allow drivers to prevent new writable mappings") changed i_mmap_writable from unsigned int to atomic_t and add the helper function mapping_allow_writable() to atomic_inc i_mmap_writable. But it forgot to use this helper function in dup_mmap() and __vma_link_file(). Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Christian Brauner <christian.brauner@ubuntu.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Christian Kellner <christian@kellner.me> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Adrian Reber <areber@redhat.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Aleksa Sarai <cyphar@cyphar.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200917112736.7789-1-linmiaohe@huawei.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/mmap: check on file instead of the rb_root_cached of its address_spaceGravatar Wei Yang 1-3/+3
In __vma_adjust(), we do the check on *root* to decide whether to adjust the address_space. It seems to be more meaningful to do the check on *file* itself. This means we are adjusting some data because it is a file backed vma. Since we seem to assume the address_space is valid if it is a file backed vma, let's just replace *root* with *file* here. Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Link: https://lkml.kernel.org/r/20200913133631.37781-2-richard.weiyang@linux.alibaba.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/mmap: not necessary to check mapping separatelyGravatar Wei Yang 1-2/+1
*root* with type of struct rb_root_cached is an element of *mapping* with type of struct address_space. This implies when we have a valid *root* it must be a part of valid *mapping*. So we can merge these two checks together to make the code more easy to read and to save some cpu cycles. Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Link: https://lkml.kernel.org/r/20200913133631.37781-1-richard.weiyang@linux.alibaba.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/memory.c: fix spello of "function"Gravatar Randy Dunlap 1-1/+1
Fix typo/spello of "function". Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Link: https://lkml.kernel.org/r/e7bf180e-c558-b1d5-9a15-6d9708823c9c@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/mmap: leave adjust_next as virtual address instead of page frame numberGravatar Wei Yang 2-6/+6
Instead of converting adjust_next between bytes and pages number, let's just store the virtual address into adjust_next. Also, this patch fixes one typo in the comment of vma_adjust_trans_huge(). [vbabka@suse.cz: changelog tweak] Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Mike Kravetz <mike.kravetz@oracle.com> Link: http://lkml.kernel.org/r/20200828081031.11306-1-richard.weiyang@linux.alibaba.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm: simplify PageDoubleMap with PF_SECOND policyGravatar Matthew Wilcox (Oracle) 1-30/+10
Introduce the new page policy of PF_SECOND which lets us use the normal pageflags generation machinery to create the various DoubleMap manipulation functions. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Zi Yan <ziy@nvidia.com> Link: https://lkml.kernel.org/r/20200629151933.15671-3-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm: move PageDoubleMap bitGravatar Matthew Wilcox (Oracle) 1-1/+1
Patch series "Fix PageDoubleMap". This is a purely theoretical problem for now as none of the filesystems which use PG_private_2 (ie PG_fscache) are being converted at this time, but it's confusing to leave it like this. This patch (of 2): PG_private_2 is defined as being PF_ANY (applicable to tail pages as well as regular & head pages). That means that the first tail page of a double-map page will appear to have Private2 set. Use the Workingset bit instead which is defined as PF_HEAD so any attempt to access the Workingset bit on a tail page will redirect to the head page's Workingset bit. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Zi Yan <ziy@nvidia.com> Link: https://lkml.kernel.org/r/20200629151933.15671-1-willy@infradead.org Link: https://lkml.kernel.org/r/20200629151933.15671-2-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm: proc: smaps_rollup: do not stall write attempts on mmap_lockGravatar Chinwen Chang 1-1/+65
smaps_rollup will try to grab mmap_lock and go through the whole vma list until it finishes the iterating. When encountering large processes, the mmap_lock will be held for a longer time, which may block other write requests like mmap and munmap from progressing smoothly. There are upcoming mmap_lock optimizations like range-based locks, but the lock applied to smaps_rollup would be the coarse type, which doesn't avoid the occurrence of unpleasant contention. To solve aforementioned issue, we add a check which detects whether anyone wants to grab mmap_lock for write attempts. Signed-off-by: Chinwen Chang <chinwen.chang@mediatek.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Steven Price <steven.price@arm.com> Cc: Michel Lespinasse <walken@google.com> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: Chinwen Chang <chinwen.chang@mediatek.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Song Liu <songliubraving@fb.com> Cc: Jimmy Assarsson <jimmyassarsson@gmail.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Daniel Kiss <daniel.kiss@arm.com> Cc: Laurent Dufour <ldufour@linux.ibm.com> Link: http://lkml.kernel.org/r/1597715898-3854-4-git-send-email-chinwen.chang@mediatek.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm: smaps*: extend smap_gather_stats to support specified beginningGravatar Chinwen Chang 1-8/+22
Extend smap_gather_stats to support indicated beginning address at which it should start gathering. To achieve the goal, we add a new parameter @start assigned by the caller and try to refactor it for simplicity. If @start is 0, it will use the range of @vma for gathering. Signed-off-by: Chinwen Chang <chinwen.chang@mediatek.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Steven Price <steven.price@arm.com> Cc: Michel Lespinasse <walken@google.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Daniel Kiss <daniel.kiss@arm.com> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: Huang Ying <ying.huang@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jimmy Assarsson <jimmyassarsson@gmail.com> Cc: Laurent Dufour <ldufour@linux.ibm.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: Song Liu <songliubraving@fb.com> Cc: Vlastimil Babka <vbabka@suse.cz> Link: http://lkml.kernel.org/r/1597715898-3854-3-git-send-email-chinwen.chang@mediatek.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mmap locking API: add mmap_lock_is_contended()Gravatar Chinwen Chang 1-0/+5
Patch series "Try to release mmap_lock temporarily in smaps_rollup", v4. Recently, we have observed some janky issues caused by unpleasantly long contention on mmap_lock which is held by smaps_rollup when probing large processes. To address the problem, we let smaps_rollup detect if anyone wants to acquire mmap_lock for write attempts. If yes, just release the lock temporarily to ease the contention. smaps_rollup is a procfs interface which allows users to summarize the process's memory usage without the overhead of seq_* calls. Android uses it to sample the memory usage of various processes to balance its memory pool sizes. If no one wants to take the lock for write requests, smaps_rollup with this patch will behave like the original one. Although there are on-going mmap_lock optimizations like range-based locks, the lock applied to smaps_rollup would be the coarse one, which is hard to avoid the occurrence of aforementioned issues. So the detection and temporary release for write attempts on mmap_lock in smaps_rollup is still necessary. This patch (of 3): Add new API to query if someone wants to acquire mmap_lock for write attempts. Using this instead of rwsem_is_contended makes it more tolerant of future changes to the lock type. Signed-off-by: Chinwen Chang <chinwen.chang@mediatek.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Steven Price <steven.price@arm.com> Acked-by: Michel Lespinasse <walken@google.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Daniel Kiss <daniel.kiss@arm.com> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: Huang Ying <ying.huang@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jimmy Assarsson <jimmyassarsson@gmail.com> Cc: Laurent Dufour <ldufour@linux.ibm.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: Song Liu <songliubraving@fb.com> Cc: Vlastimil Babka <vbabka@suse.cz> Link: http://lkml.kernel.org/r/1597715898-3854-1-git-send-email-chinwen.chang@mediatek.com Link: http://lkml.kernel.org/r/1597715898-3854-2-git-send-email-chinwen.chang@mediatek.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/mmap: leverage vma_rb_erase_ignore() to implement vma_rb_erase()Gravatar Wei Yang 1-9/+7
These two functions share the same logic except ignore a different vma. Let's reuse the code. Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Link: https://lkml.kernel.org/r/20200809232057.23477-2-richard.weiyang@linux.alibaba.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/mmap: rename __vma_unlink_common() to __vma_unlink()Gravatar Wei Yang 1-3/+3
__vma_unlink_common() and __vma_unlink() are counterparts. Since there is no function named __vma_unlink(), let's rename __vma_unlink_common() to __vma_unlink() to make the code more self-explanatory and easy for audience to understand. Otherwise we may expect there are several variants of vma_unlink() and __vma_unlink_common() is used by them. Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Link: https://lkml.kernel.org/r/20200809232057.23477-1-richard.weiyang@linux.alibaba.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/memory.c: replace vmf->vma with variable vmaGravatar Yanfei Xu 1-1/+1
The code has declared a vma_struct named vma which is assigned a value of vmf->vma. Thus, use variable vma directly here. Signed-off-by: Yanfei Xu <yanfei.xu@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Link: http://lkml.kernel.org/r/20200818084607.37616-1-yanfei.xu@windriver.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/memory.c: fix typo in __do_fault() commentGravatar Yanfei Xu 1-1/+1
It's "pte_alloc_one", not "pte_alloc_pne". Let's fix that. Signed-off-by: Yanfei Xu <yanfei.xu@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: David Hildenbrand <david@redhat.com> Link: http://lkml.kernel.org/r/20200818104339.5310-1-yanfei.xu@windriver.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm: account PMD tables like PTE tablesGravatar Matthew Wilcox 2-4/+21
We account the PTE level of the page tables to the process in order to make smarter OOM decisions and help diagnose why memory is fragmented. For these same reasons, we should account pages allocated for PMDs. With larger process address spaces and ASLR, the number of PMDs in use is higher than it used to be so the inaccuracy is starting to matter. [rppt@linux.ibm.com: arm: __pmd_free_tlb(): call page table destructor] Link: https://lkml.kernel.org/r/20200825111303.GB69694@linux.ibm.com Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Rapoport <rppt@linux.ibm.com> Cc: Abdul Haleem <abdhalee@linux.vnet.ibm.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Joerg Roedel <joro@8bytes.org> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Cc: Stafford Horne <shorne@gmail.com> Cc: Naresh Kamboju <naresh.kamboju@linaro.org> Cc: Anders Roxell <anders.roxell@linaro.org> Link: http://lkml.kernel.org/r/20200627184642.GF25039@casper.infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13selftests/vm: fix incorrect gcc invocation in some casesGravatar John Hubbard 1-0/+12
Avoid accidental wrong builds, due to built-in rules working just a little bit too well--but not quite as well as required for our situation here. In other words, "make userfaultfd" (for example) is supposed to fail to build at all, because this Makefile only supports either "make" (all), or "make /full/path". However, the built-in rules, if not suppressed, will pick up CFLAGS and the initial LDLIBS (but not the target-specific LDLIBS, because those are only set for the full path target!). This causes it to get pretty far into building things despite using incorrect values such as an *occasionally* incomplete LDLIBS value. Signed-off-by: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Jason Gunthorpe <jgg@ziepe.ca> Link: https://lkml.kernel.org/r/20200915012901.1655280-3-jhubbard@nvidia.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13selftests/vm: fix false build success on the second and later attemptsGravatar John Hubbard 1-0/+5
Patch series "selftests/vm: fix some minor aggravating factors in the Makefile". This fixes a couple of minor aggravating factors that I ran across while trying to do some changes in selftests/vm. These are simple things, but like most things with GNU Make, it's rarely obvious what's wrong until you understand *the entire Makefile and all of its includes*. So while there is, of course, joy in learning those details, I thought I'd fix these little things, so as to allow others to skip out on the Joy if they so choose. :) First of all, if you have an item (let's choose userfaultfd for an example) that fails to build, you might do this: $ make -j32 # ...you observe a failed item in the threaded output # OK, let's get a closer look $ make # ...but now the build quietly "succeeds". That's what Patch 0001 fixes. Second, if you instead attempt this approach for your closer look (a casual mistake, as it's not supported): $ make userfaultfd # ...userfaultfd fails to link, due to incomplete LDLIBS That's what Patch 0002 fixes. This patch (of 2): If one or more of these selftest fail to build, then after the first failure, subsequent invocations of "make" will make it appear that there are no build failures, after all. That's because the failed build products remain, with up-to-date timestamps, thus tricking Make (and you!) into believing that there's nothing else to build. Fix this by telling Make to delete targets that didn't completely succeed. Signed-off-by: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Jason Gunthorpe <jgg@ziepe.ca> Link: https://lkml.kernel.org/r/20200915012901.1655280-1-jhubbard@nvidia.com Link: https://lkml.kernel.org/r/20200915012901.1655280-2-jhubbard@nvidia.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/memcg: fix device private memcg accountingGravatar Ralph Campbell 1-1/+4
The code in mc_handle_swap_pte() checks for non_swap_entry() and returns NULL before checking is_device_private_entry() so device private pages are never handled. Fix this by checking for non_swap_entry() after handling device private swap PTEs. I assume the memory cgroup accounting would be off somehow when moving a process to another memory cgroup. Currently, the device private page is charged like a normal anonymous page when allocated and is uncharged when the page is freed so I think that path is OK. Signed-off-by: Ralph Campbell <rcampbell@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Ira Weiny <ira.weiny@intel.com> Link: https://lkml.kernel.org/r/20201009215952.2726-1-rcampbell@nvidia.com xFixes: c733a82874a7 ("mm/memcontrol: support MEMORY_DEVICE_PRIVATE") Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm: memcg/slab: uncharge during kmem_cache_free_bulk()Gravatar Bharata B Rao 3-17/+30
Object cgroup charging is done for all the objects during allocation, but during freeing, uncharging ends up happening for only one object in the case of bulk allocation/freeing. Fix this by having a separate call to uncharge all the objects from kmem_cache_free_bulk() and by modifying memcg_slab_free_hook() to take care of bulk uncharging. Fixes: 964d4bd370d5 ("mm: memcg/slab: save obj_cgroup for non-root slab objects" Signed-off-by: Bharata B Rao <bharata@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Roman Gushchin <guro@fb.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Shakeel Butt <shakeelb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Tejun Heo <tj@kernel.org> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20201009060423.390479-1-bharata@linux.ibm.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm: memcontrol: reword obsolete comment of mem_cgroup_unmark_under_oom()Gravatar Miaohe Lin 1-2/+2
Since commit 79dfdaccd1d5 ("memcg: make oom_lock 0 and 1 based rather than counter"), the mem_cgroup_unmark_under_oom() is added and the comment of the mem_cgroup_oom_unlock() is moved here. But this comment make no sense here because mem_cgroup_oom_lock() does not operate on under_oom field. So we reword the comment as this would be helpful. [Thanks Michal Hocko for rewording this comment.] Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Link: https://lkml.kernel.org/r/20200930095336.21323-1-linmiaohe@huawei.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/page_counter: correct the obsolete func name in the comment of ↵Gravatar Miaohe Lin 1-1/+1
page_counter_try_charge() Since commit bbec2e15170a ("mm: rename page_counter's count/limit into usage/max"), page_counter_limit() is renamed to page_counter_set_max(). So replace page_counter_limit with page_counter_set_max in comment. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Roman Gushchin <guro@fb.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Link: https://lkml.kernel.org/r/20200917113629.14382-1-linmiaohe@huawei.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm: memcontrol: add the missing numa_stat interface for cgroup v2Gravatar Muchun Song 2-80/+159
In the cgroup v1, we have a numa_stat interface. This is useful for providing visibility into the numa locality information within an memcg since the pages are allowed to be allocated from any physical node. One of the use cases is evaluating application performance by combining this information with the application's CPU allocation. But the cgroup v2 does not. So this patch adds the missing information. Suggested-by: Shakeel Butt <shakeelb@google.com> Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Shakeel Butt <shakeelb@google.com> Cc: Zefan Li <lizefan@huawei.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Roman Gushchin <guro@fb.com> Cc: Randy Dunlap <rdunlap@infradead.org> Link: https://lkml.kernel.org/r/20200916100030.71698-2-songmuchun@bytedance.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/memcg: unify swap and memsw page countersGravatar Waiman Long 2-8/+8
The swap page counter is v2 only while memsw is v1 only. As v1 and v2 controllers cannot be active at the same time, there is no point to keep both swap and memsw page counters in mem_cgroup. The previous patch has made sure that memsw page counter is updated and accessed only when in v1 code paths. So it is now safe to alias the v1 memsw page counter to v2 swap page counter. This saves 14 long's in the size of mem_cgroup. This is a saving of 112 bytes for 64-bit archs. While at it, also document which page counters are used in v1 and/or v2. Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Shakeel Butt <shakeelb@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Chris Down <chris@chrisdown.name> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Roman Gushchin <guro@fb.com> Cc: Tejun Heo <tj@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Yafang Shao <laoar.shao@gmail.com> Link: https://lkml.kernel.org/r/20200914024452.19167-4-longman@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/memcg: simplify mem_cgroup_get_max()Gravatar Waiman Long 1-11/+13
mem_cgroup_get_max() used to get memory+swap max from both the v1 memsw and v2 memory+swap page counters & return the maximum of these 2 values. This is redundant and it is more efficient to just get either the v1 or the v2 values depending on which one is currently in use. [longman@redhat.com: v4] Link: https://lkml.kernel.org/r/20200914150928.7841-1-longman@redhat.com Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Shakeel Butt <shakeelb@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Chris Down <chris@chrisdown.name> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Roman Gushchin <guro@fb.com> Cc: Tejun Heo <tj@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Yafang Shao <laoar.shao@gmail.com> Link: https://lkml.kernel.org/r/20200914024452.19167-3-longman@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/memcg: clean up obsolete enum charge_typeGravatar Waiman Long 1-8/+0
Patch series "mm/memcg: Miscellaneous cleanups and streamlining", v2. This patch (of 3): Since commit 0a31bc97c80c ("mm: memcontrol: rewrite uncharge API") and commit 00501b531c47 ("mm: memcontrol: rewrite charge API") in v3.17, the enum charge_type was no longer used anywhere. However, the enum itself was not removed at that time. Remove the obsolete enum charge_type now. Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Shakeel Butt <shakeelb@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Chris Down <chris@chrisdown.name> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Tejun Heo <tj@kernel.org> Cc: Roman Gushchin <guro@fb.com> Cc: Yafang Shao <laoar.shao@gmail.com> Link: https://lkml.kernel.org/r/20200914024452.19167-1-longman@redhat.com Link: https://lkml.kernel.org/r/20200914024452.19167-2-longman@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm: memcontrol: correct the comment of mem_cgroup_iter()Gravatar Miaohe Lin 1-3/+3
Since commit bbec2e15170a ("mm: rename page_counter's count/limit into usage/max"), the arg @reclaim has no priority field anymore. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Link: https://lkml.kernel.org/r/20200913094129.44558-1-linmiaohe@huawei.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm: memcg/slab: fix racy access to page->mem_cgroup in mem_cgroup_from_obj()Gravatar Roman Gushchin 1-0/+11
mem_cgroup_from_obj() checks the lowest bit of the page->mem_cgroup pointer to determine if the page has an attached obj_cgroup vector instead of a regular memcg pointer. If it's not set, it simple returns the page->mem_cgroup value as a struct mem_cgroup pointer. The commit 10befea91b61 ("mm: memcg/slab: use a single set of kmem_caches for all allocations") changed the moment when this bit is set: if previously it was set on the allocation of the slab page, now it can be set well after, when the first accounted object is allocated on this page. It opened a race: if page->mem_cgroup is set concurrently after the first page_has_obj_cgroups(page) check, a pointer to the obj_cgroups array can be returned as a memory cgroup pointer. A simple check for page->mem_cgroup pointer for NULL before the page_has_obj_cgroups() check fixes the race. Indeed, if the pointer is not NULL, it's either a simple mem_cgroup pointer or a pointer to obj_cgroup vector. The pointer can be asynchronously changed from NULL to (obj_cgroup_vec | 0x1UL), but can't be changed from a valid memcg pointer to objcg vector or back. If the object passed to mem_cgroup_from_obj() is a slab object and page->mem_cgroup is NULL, it means that the object is not accounted, so the function must return NULL. I've discovered the race looking at the code, so far I haven't seen it in the wild. Fixes: 10befea91b61 ("mm: memcg/slab: use a single set of kmem_caches for all allocations") Signed-off-by: Roman Gushchin <guro@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Shakeel Butt <shakeelb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vlastimil Babka <vbabka@suse.cz> Link: https://lkml.kernel.org/r/20200910022435.2773735-1-guro@fb.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm: memcontrol: use the preferred form for passing the size of a structure typeGravatar Gustavo A. R. Silva 1-1/+1
Use the preferred form for passing the size of a structure type. The alternative form where the structure type is spelled out hurts readability and introduces an opportunity for a bug when the object type is changed but the corresponding object identifier to which the sizeof operator is applied is not. Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Link: https://lkml.kernel.org/r/773e013ff2f07fe2a0b47153f14dea054c0c04f1.1596214831.git.gustavoars@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm: memcontrol: use flex_array_size() helper in memcpy()Gravatar Gustavo A. R. Silva 1-4/+3
Make use of the flex_array_size() helper to calculate the size of a flexible array member within an enclosing structure. This helper offers defense-in-depth against potential integer overflows, while at the same time makes it explicitly clear that we are dealing with a flexible array member. Also, remove unnecessary braces. Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Link: https://lkml.kernel.org/r/ddd60dae2d9aea1ccdd2be66634815c93696125e.1596214831.git.gustavoars@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>