- Mar 25, 2022
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Andrey Konovalov authored
Patch series "kasan, vmalloc, arm64: add vmalloc tagging support for SW/HW_TAGS", v6. This patchset adds vmalloc tagging support for SW_TAGS and HW_TAGS KASAN modes. About half of patches are cleanups I went for along the way. None of them seem to be important enough to go through stable, so I decided not to split them out into separate patches/series. The patchset is partially based on an early version of the HW_TAGS patchset by Vincenzo that had vmalloc support. Thus, I added a Co-developed-by tag into a few patches. SW_TAGS vmalloc tagging support is straightforward. It reuses all of the generic KASAN machinery, but uses shadow memory to store tags instead of magic values. Naturally, vmalloc tagging requires adding a few kasan_reset_tag() annotations to the vmalloc code. HW_TAGS vmalloc tagging support stands out. HW_TAGS KASAN is based on Arm MTE, which can only assigns tags to physical memory. As a result, HW_TAGS KASAN only tags vmalloc() allocations, which are backed by page_alloc memory. It ignores vmap() and others. This patch (of 39): Currently, should_skip_kasan_poison() has two definitions: one for when CONFIG_DEFERRED_STRUCT_PAGE_INIT is enabled, one for when it's not. Instead of duplicating the checks, add a deferred_pages_enabled() helper and use it in a single should_skip_kasan_poison() definition. Also move should_skip_kasan_poison() closer to its caller and clarify all conditions in the comment. Link: https://lkml.kernel.org/r/cover.1643047180.git.andreyknvl@google.com Link: https://lkml.kernel.org/r/658b79f5fb305edaf7dc16bc52ea870d3220d4a8.1643047180.git.andreyknvl@google.com Signed-off-by:
Andrey Konovalov <andreyknvl@google.com> Acked-by:
Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Evgenii Stepanov <eugenis@google.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Anshuman Khandual authored
This adds two trace events for base page and HugeTLB page migrations. These events, closely follow the implementation details like setting and removing of PTE migration entries, which are essential operations for migration. The new CREATE_TRACE_POINTS in <mm/rmap.c> covers both <events/migration.h> and <events/tlb.h> based trace events. Hence drop redundant CREATE_TRACE_POINTS from other places which could have otherwise conflicted during build. Link: https://lkml.kernel.org/r/1643368182-9588-3-git-send-email-anshuman.khandual@arm.com Signed-off-by:
Anshuman Khandual <anshuman.khandual@arm.com> Reported-by:
kernel test robot <lkp@intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Naoya Horiguchi <naoya.horiguchi@nec.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by:
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Anshuman Khandual authored
Patch series "mm/migration: Add trace events", v3. This adds trace events for all migration scenarios including base page, THP and HugeTLB. This patch (of 3): This adds two trace events for PMD based THP migration without split. These events closely follow the implementation details like setting and removing of PMD migration entries, which are essential operations for THP migration. This moves CREATE_TRACE_POINTS into generic THP from powerpc for these new trace events to be available on other platforms as well. Link: https://lkml.kernel.org/r/1643368182-9588-1-git-send-email-anshuman.khandual@arm.com Link: https://lkml.kernel.org/r/1643368182-9588-2-git-send-email-anshuman.khandual@arm.com Signed-off-by:
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Hugh Dickins authored
NR_FILE_MAPPED accounting in mm/rmap.c (for /proc/meminfo "Mapped" and /proc/vmstat "nr_mapped" and the memcg's memory.stat "mapped_file") is slightly flawed for file or shmem huge pages. It is well thought out, and looks convincing, but there's a racy case when the careful counting in page_remove_file_rmap() (without page lock) gets discarded. So that in a workload like two "make -j20" kernel builds under memory pressure, with cc1 on hugepage text, "Mapped" can easily grow by a spurious 5MB or more on each iteration, ending up implausibly bigger than most other numbers in /proc/meminfo. And, hypothetically, might grow to the point of seriously interfering in mm/vmscan.c's heuristics, which do take NR_FILE_MAPPED into some consideration. Fixed by moving the __mod_lruvec_page_state() down to where it will not be missed before return (and I've grown a bit tired of that oft-repeated but-not-everywhere comment on the __ness: it gets lost in the move here). Does page_add_file_rmap() need the same change? I suspect not, because page lock is held in all relevant cases, and its skipping case looks safe; but it's much easier to be sure, if we do make the same change. Link: https://lkml.kernel.org/r/e02e52a1-8550-a57c-ed29-f51191ea2375@google.com Fixes: dd78fedd ("rmap: support file thp") Signed-off-by:
Hugh Dickins <hughd@google.com> Reviewed-by:
Yang Shi <shy828301@gmail.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Signed-off-by:
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Hugh Dickins authored
The page_mapcount_reset() when folio_mapped() while mapping_exiting() was devised long before there were huge or compound pages in the cache. It is still valid for small pages, but not at all clear what's right to check and reset on large pages. Just don't try when folio_test_large(). Link: https://lkml.kernel.org/r/879c4426-4122-da9c-1a86-697f2c9a083@google.com Signed-off-by:
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Hugh Dickins authored
The PG_waiters bit is not included in PAGE_FLAGS_CHECK_AT_FREE, and vmscan.c's free_unref_page_list() callers rely on that not to generate bad_page() alerts. So __page_cache_release(), put_pages_list() and release_pages() (and presumably copy-and-pasted free_zone_device_page()) are redundant and misleading to make a special point of clearing it (as the "__" implies, it could only safely be used on the freeing path). Delete __ClearPageWaiters(). Remark on this in one of the "possible" comments in folio_wake_bit(), and delete the superfluous comments. Link: https://lkml.kernel.org/r/3eafa969-5b1a-accf-88fe-318784c791a@google.com Signed-off-by:
Yu Zhao <yuzhao@google.com> Reviewed-by:
David Hildenbrand <david@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Yu Zhao <yuzhao@google.com> Cc: Michal Hocko <mhocko@suse.com> Signed-off-by:
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Mike Rapoport authored
PAGE_SIZE is not 4096 in many configurations, particularly ppc64 uses 64K pages in majority of cases. Add helpers to detect PAGE_SIZE and PAGE_SHIFT dynamically. Without this tests are broken w.r.t reading /proc/self/pagemap if (pread(pagemap_fd, ent, sizeof(ent), (uintptr_t)ptr >> (PAGE_SHIFT - 3)) != sizeof(ent)) err(2, "read pagemap"); Link: https://lkml.kernel.org/r/20220307054355.149820-2-aneesh.kumar@linux.ibm.com Signed-off-by:Mike Rapoport <rppt@linux.ibm.com> Signed-off-by:
Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by:
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Aneesh Kumar K.V authored
Avoid code duplication by adding util.h. No functional change in this patch. Link: https://lkml.kernel.org/r/20220307054355.149820-1-aneesh.kumar@linux.ibm.com Signed-off-by:
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Christoph Hellwig authored
page_init_poison is only used in core MM code, so unexport it. Link: https://lkml.kernel.org/r/20220207063446.1833404-1-hch@lst.de Signed-off-by:
Christoph Hellwig <hch@lst.de> Reviewed-by:
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Jiajian Ye authored
When viewing page owner information, we may want to cull blocks of information with our own rules. So it is important to enhance culling function to provide the support for customizing culling rules. Therefore, following adjustments are made: 1. Add --cull option to support the culling of blocks of information with user-defined culling rules. ./page_owner_sort <input> <output> --cull=<rules> ./page_owner_sort <input> <output> --cull <rules> <rules> is a single argument in the form of a comma-separated list to specify individual culling rules, by the sequence of keys k1,k2, .... Mixed use of abbreviated and complete-form of keys is allowed. For reference, please see the document(Documentation/vm/page_owner.rst). Now, assuming two blocks in the input file are as follows: Page allocated via order 0, mask xxxx, pid 1, tgid 1 (task_name_demo) PFN xxxx prep_new_page+0xd0/0xf8 get_page_from_freelist+0x4a0/0x1290 __alloc_pages+0x168/0x340 alloc_pages+0xb0/0x158 Page allocated via order 0, mask xxxx, pid 32, tgid 32 (task_name_demo) PFN xxxx prep_new_page+0xd0/0xf8 get_page_from_freelist+0x4a0/0x1290 __alloc_pages+0x168/0x340 alloc_pages+0xb0/0x158 If we want to cull the blocks by stacktrace and task command name, we can use this command: ./page_owner_sort <input> <output> --cull=stacktrace,name The output would be like: 2 times, 2 pages, task_comm_name: task_name_demo prep_new_page+0xd0/0xf8 get_page_from_freelist+0x4a0/0x1290 __alloc_pages+0x168/0x340 alloc_pages+0xb0/0x158 As we can see, these two blocks are culled successfully, for they share the same pid and task command name. However, if we want to cull the blocks by pid, stacktrace and task command name, we can this command: ./page_owner_sort <input> <output> --cull=stacktrace,name,pid The output would be like: 1 times, 1 pages, PID 1, task_comm_name: task_name_demo prep_new_page+0xd0/0xf8 get_page_from_freelist+0x4a0/0x1290 __alloc_pages+0x168/0x340 alloc_pages+0xb0/0x158 1 times, 1 pages, PID 32, task_comm_name: task_name_demo prep_new_page+0xd0/0xf8 get_page_from_freelist+0x4a0/0x1290 __alloc_pages+0x168/0x340 alloc_pages+0xb0/0x158 As we can see, these two blocks are failed to cull, for their PIDs are different. 2. Add explanations of --cull options to the document. This work is coauthored by Yixuan Cao Shenghong Han Yinan Zhang Chongxi Zhao Yuhong Feng Link: https://lkml.kernel.org/r/20220312145834.624-1-yejiajian2018@email.szu.edu.cn Signed-off-by:
Jiajian Ye <yejiajian2018@email.szu.edu.cn> Cc: Yixuan Cao <caoyixuan2019@email.szu.edu.cn> Cc: Shenghong Han <hanshenghong2019@email.szu.edu.cn> Cc: Yinan Zhang <zhangyinan2019@email.szu.edu.cn> Cc: Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn> Cc: Yuhong Feng <yuhongf@szu.edu.cn> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Sean Anderson <seanga2@gmail.com> Signed-off-by:
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Jiajian Ye authored
When viewing page owner information, we may also need to select the blocks by PID, TGID or task command name, which helps to get more accurate page allocation information as needed. Therefore, following adjustments are made: 1. Add three new options, including --pid, --tgid and --name, to support the selection of information blocks by a specific pid, tgid and task command name. In addtion, multiple options are allowed to be used at the same time. ./page_owner_sort [input] [output] --pid <PID> ./page_owner_sort [input] [output] --tgid <TGID> ./page_owner_sort [input] [output] --name <TASK_COMMAND_NAME> Assuming a scenario when a multi-threaded program, ./demo (PID = 5280), is running, and ./demo creates a child process (PID = 5281). $ps PID TTY TIME CMD 5215 pts/0 00:00:00 bash 5280 pts/0 00:00:00 ./demo 5281 pts/0 00:00:00 ./demo 5282 pts/0 00:00:00 ps It would be better to filter out the records with tgid=5280 and the task name "demo" when debugging the parent process, and the specific usage is ./page_owner_sort [input] [output] --tgid 5280 --name demo 2. Add explanations of three new options, including --pid, --tgid and --name, to the document. This work is coauthored by Shenghong Han <hanshenghong2019@email.szu.edu.cn>, Yixuan Cao <caoyixuan2019@email.szu.edu.cn>, Yinan Zhang <zhangyinan2019@email.szu.edu.cn>, Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn>, Yuhong Feng <yuhongf@szu.edu.cn>. Link: https://lkml.kernel.org/r/1646835223-7584-1-git-send-email-yejiajian2018@email.szu.edu.cn Signed-off-by:
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Jiajian Ye authored
When viewing page owner information, we may also need to the block to be sorted by task command name. Therefore, the following adjustments are made: 1. Add a member variable to record task command name of block. 2. Add a new -n option to sort the information of blocks by task command name. 3. Add -n option explanation in the document. Link: https://lkml.kernel.org/r/20220306030640.43054-2-yejiajian2018@email.szu.edu.cn Signed-off-by:
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Jiajian Ye authored
The following adjustments are made: 1. Instead of using another array to cull the blocks after sorting, reuse the old array. So there is no need to malloc a new array. 2. When enabling '-f' option to filter out the blocks which have been released, only add those have not been released in the list, rather than add all of blocks in the list and then do the filtering when printing the result. 3. When enabling '-c' option to cull the blocks by comparing stacktrace, print the stacetrace rather than the total block. Link: https://lkml.kernel.org/r/20220306030640.43054-1-yejiajian2018@email.szu.edu.cn Signed-off-by:
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Jiajian Ye authored
When the "page owner" information is read, the information sorted by TGID is expected. As a result, the following adjustments have been made: 1. Add a new -P option to sort the information of blocks by TGID in ascending order. 2. Adjust the order of member variables in block_list strust to avoid one 4 byte hole. 3. Add -P option explanation in the document. Link: https://lkml.kernel.org/r/20220301151438.166118-3-yejiajian2018@email.szu.edu.cn Signed-off-by:
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Jiajian Ye authored
Add a security check after using malloc() to allocate memory. Link: https://lkml.kernel.org/r/20220301151438.166118-2-yejiajian2018@email.szu.edu.cn Signed-off-by:
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Jiajian Ye authored
Two adjustments are made: 1. Correct a grammatical error: replace the "what" in "Do the job what you want to debug" with "that". 2. Replace "has not been" with "has been" in the description of the -f option: According to Commit b1c9ba071e7d ("tools/vm/page_owner_sort.c: fix the instructions for use"), the description of the "-f" option is "Filter out the information of blocks whose memory has been released." Link: https://lkml.kernel.org/r/20220301151438.166118-1-yejiajian2018@email.szu.edu.cn Signed-off-by: -
Yixuan Cao authored
I noticed a discrepancy between the usage method and the code logic. If we enable the -f option, it should be "Filter out the information of blocks whose memory has been released". Link: https://lkml.kernel.org/r/20220219143106.2805-1-caoyixuan2019@email.szu.edu.cn Signed-off-by:
Yixuan Cao <caoyixuan2019@email.szu.edu.cn> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Sean Anderson <seanga2@gmail.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Zhenliang Wei <weizhenliang@huawei.com> Cc: Tang Bin <tangbin@cmss.chinamobile.com> Cc: Yinan Zhang <zhangyinan2019@email.szu.edu.cn> Signed-off-by:
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Yixuan Cao authored
In a single-threaded process, the pid in kernel task_struct is the same as the tgid, which can mark the process of page allocation. But in a multithreaded process, only the task_struct of the thread leader has the same pid as tgid, and the pids of other threads are different from tgid. Therefore, tgid is recorded to provide effective information for debugging and data statistics of multithreaded programs. This can also be achieved by observing the task name (executable file name) for a specific process. However, when the same program is started multiple times, the task name is the same and the tgid is different. Therefore, in the debugging of multi-threaded programs, combined with the task name and tgid, more accurate runtime information of a certain run of the program can be obtained. Link: https://lkml.kernel.org/r/20220219180450.2399-1-caoyixuan2019@email.szu.edu.cn Signed-off-by:
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Waiman Long authored
The page_owner information currently includes the pid of the calling task. That is useful as long as the task is still running. Otherwise, the number is meaningless. To have more information about the allocating tasks that had exited by the time the page_owner information is retrieved, we need to store the command name of the task. Add a new comm field into page_owner structure to store the command name and display it when the page_owner information is retrieved. Link: https://lkml.kernel.org/r/20220202203036.744010-5-longman@redhat.com Signed-off-by:
Waiman Long <longman@redhat.com> Acked-by:
Rafael Aquini <aquini@redhat.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Mike Rapoport <rppt@kernel.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Steven Rostedt (Google) <rostedt@goodmis.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Signed-off-by:
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Waiman Long authored
It was found that a number of offline memcgs were not freed because they were pinned by some charged pages that were present. Even "echo 1 > /proc/sys/vm/drop_caches" wasn't able to free those pages. These offline but not freed memcgs tend to increase in number over time with the side effect that percpu memory consumption as shown in /proc/meminfo also increases over time. In order to find out more information about those pages that pin offline memcgs, the page_owner feature is extended to print memory cgroup information especially whether the cgroup is offline or not. RCU read lock is taken when memcg is being accessed to make sure that it won't be freed. Link: https://lkml.kernel.org/r/20220202203036.744010-4-longman@redhat.com Signed-off-by:
David Rientjes <rientjes@google.com> Acked-by:
Roman Gushchin <guro@fb.com> Acked-by:
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Waiman Long authored
The snprintf() function can return a length greater than the given input size. That will require a check for buffer overrun after each invocation of snprintf(). scnprintf(), on the other hand, will never return a greater length. By using scnprintf() in selected places, we can avoid some buffer overrun checks except after stack_depot_snprint() and after the last snprintf(). Link: https://lkml.kernel.org/r/20220202203036.744010-3-longman@redhat.com Signed-off-by:
Sergey Senozhatsky <senozhatsky@chromium.org> Acked-by:
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Waiman Long authored
Patch series "mm/page_owner: Extend page_owner to show memcg information", v4. While debugging the constant increase in percpu memory consumption on a system that spawned large number of containers, it was found that a lot of offline mem_cgroup structures remained in place without being freed. Further investigation indicated that those mem_cgroup structures were pinned by some pages. In order to find out what those pages are, the existing page_owner debugging tool is extended to show memory cgroup information and whether those memcgs are offline or not. With the enhanced page_owner tool, the following is a typical page that pinned the mem_cgroup structure in my test case: Page allocated via order 0, mask 0x1100cca(GFP_HIGHUSER_MOVABLE), pid 162970 (podman), ts 1097761405537 ns, free_ts 1097760838089 ns PFN 1925700 type Movable Block 3761 type Movable Flags 0x17ffffc00c001c(uptodate|dirty|lru|reclaim|swapbacked|node=0|zone=2|lastcpupid=0x1fffff) prep_new_page+0xac/0xe0 get_page_from_freelist+0x1327/0x14d0 __alloc_pages+0x191/0x340 alloc_pages_vma+0x84/0x250 shmem_alloc_page+0x3f/0x90 shmem_alloc_and_acct_page+0x76/0x1c0 shmem_getpage_gfp+0x281/0x940 shmem_write_begin+0x36/0xe0 generic_perform_write+0xed/0x1d0 __generic_file_write_iter+0xdc/0x1b0 generic_file_write_iter+0x5d/0xb0 new_sync_write+0x11f/0x1b0 vfs_write+0x1ba/0x2a0 ksys_write+0x59/0xd0 do_syscall_64+0x37/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae Charged to offline memcg libpod-conmon-15e4f9c758422306b73b2dd99f9d50a5ea53cbb16b4a13a2c2308a4253cc0ec8. So the page was not freed because it was part of a shmem segment. That is useful information that can help users to diagnose similar problems. With cgroup v1, /proc/cgroups can be read to find out the total number of memory cgroups (online + offline). With cgroup v2, the cgroup.stat of the root cgroup can be read to find the number of dying cgroups (most likely pinned by dying memcgs). The page_owner feature is not supposed to be enabled for production system due to its memory overhead. However, if it is suspected that dying memcgs are increasing over time, a test environment with page_owner enabled can then be set up with appropriate workload for further analysis on what may be causing the increasing number of dying memcgs. This patch (of 4): For *scnprintf(), vsnprintf() is always called even if the input size is 0. That is a waste of time, so just return 0 in this case. Note that vsnprintf() will never return -1 to indicate an error. So skipping the call to vsnprintf() when size is 0 will have no functional impact at all. Link: https://lkml.kernel.org/r/20220202203036.744010-1-longman@redhat.com Link: https://lkml.kernel.org/r/20220202203036.744010-2-longman@redhat.com Signed-off-by: -
Shuah Khan authored
Fix Unexpected indentation warns in page_owner: Documentation/vm/page_owner.rst:92: WARNING: Unexpected indentation. Documentation/vm/page_owner.rst:96: WARNING: Unexpected indentation. Documentation/vm/page_owner.rst:107: WARNING: Unexpected indentation. Link: https://lkml.kernel.org/r/20211215001929.47866-1-skhan@linuxfoundation.org Signed-off-by:
Shuah Khan <skhan@linuxfoundation.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by:
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Shenghong Han authored
Update the documentation of ``page_owner``. [akpm@linux-foundation.org: small grammatical tweaks] Link: https://lkml.kernel.org/r/20211214134736.2569-1-hanshenghong2019@email.szu.edu.cn Signed-off-by:
Shenghong Han <hanshenghong2019@email.szu.edu.cn> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Georgi Djakov <georgi.djakov@linaro.org> Cc: Liam Mark <lmark@codeaurora.org> Cc: Tang Bin <tangbin@cmss.chinamobile.com> Cc: Zhang Shengju <zhangshengju@cmss.chinamobile.com> Cc: Zhenliang Wei <weizhenliang@huawei.com> Cc: Xiaoming Ni <nixiaoming@huawei.com> Signed-off-by:
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Yixuan Cao authored
I noticed that there is two invalid lines of duplicate code. It's better to delete it. Link: https://lkml.kernel.org/r/20211213095743.3630-1-caoyixuan2019@email.szu.edu.cn Signed-off-by:
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Shenghong Han authored
1) There is an unused variable. It's better to delete it. 2) One case is missing in the usage(). Link: https://lkml.kernel.org/r/20211213164518.2461-1-hanshenghong2019@email.szu.edu.cn Signed-off-by:
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Chongxi Zhao authored
When viewing the page owner information, we expect that the information can be sorted by PID, so that we can quickly combine PID with the program to check the information together. We also expect that the information can be sorted by time. Time sorting helps to view the running status of the program according to the time interval when the program hangs up. Finally, we hope to pass the page_ owner_ Sort. C can reduce part of the output and only output the plate information whose memory has not been released, which can make us locate the problem of the program faster. Therefore, the following adjustments have been made: 1. Add the static functions search_pattern and check_regcomp to improve the cleanliness. 2. Add member attributes and their corresponding sorting methods. In terms of comparison time, int will overflow because the data of ull is too large, so the ternary operator is used 3. Add the -f parameter to filter out the information of blocks whose memory has not been released Link: https://lkml.kernel.org/r/20211206165653.5093-1-zhaochongxi2019@email.szu.edu.cn Signed-off-by:
Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn> Reviewed-by:
Sean Anderson <seanga2@gmail.com> Signed-off-by:
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Yinan Zhang authored
Culling by comparing stacktrace would casue loss of some information. For example, if there exists 2 blocks which have the same stacktrace and the different head info Page allocated via order 0, mask 0x108c48(...), pid 73696, ts 1578829190639010 ns, free_ts 1576583851324450 ns prep_new_page+0x80/0xb8 get_page_from_freelist+0x924/0xee8 __alloc_pages+0x138/0xc18 alloc_pages+0x80/0xf0 __page_cache_alloc+0x90/0xc8 Page allocated via order 0, mask 0x108c48(...), pid 61806, ts 1354113726046100 ns, free_ts 1354104926841400 ns prep_new_page+0x80/0xb8 get_page_from_freelist+0x924/0xee8 __alloc_pages+0x138/0xc18 alloc_pages+0x80/0xf0 __page_cache_alloc+0x90/0xc8 After culling, it would be like this 2 times, 2 pages: Page allocated via order 0, mask 0x108c48(...), pid 73696, ts 1578829190639010 ns, free_ts 1576583851324450 ns prep_new_page+0x80/0xb8 get_page_from_freelist+0x924/0xee8 __alloc_pages+0x138/0xc18 alloc_pages+0x80/0xf0 __page_cache_alloc+0x90/0xc8 The info of second block missed. So, add -c to turn on culling by stacktrace. By default, it will cull by txt. Link: https://lkml.kernel.org/r/20211129145658.2491-1-zhangyinan2019@email.szu.edu.cn Signed-off-by:Yinan Zhang <zhangyinan2019@email.szu.edu.cn> Cc: Changhee Han <ch0.han@lge.com> Cc: Sean Anderson <seanga2@gmail.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Tang Bin <tangbin@cmss.chinamobile.com> Cc: Zhang Shengju <zhangshengju@cmss.chinamobile.com> Cc: Zhenliang Wei <weizhenliang@huawei.com> Signed-off-by:
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Sean Anderson authored
This adds the ability to sort by stacktraces. This is helpful when comparing multiple dumps of page_owner taken at different times, since blocks will not be reordered if they were allocated/free'd. Link: https://lkml.kernel.org/r/20211124193709.1805776-2-seanga2@gmail.com Signed-off-by:
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Sean Anderson authored
The contents of page_owner have changed to include more information than the stack trace. On a modern kernel, the blocks look like Page allocated via order 0, mask 0x0(), pid 1, ts 165564237 ns, free_ts 0 ns register_early_stack+0x4b/0x90 init_page_owner+0x39/0x250 kernel_init_freeable+0x11e/0x242 kernel_init+0x16/0x130 Sorting by the contents of .txt will result in almost no repeated pages, as the pid, ts, and free_ts will almost never be the same. Instead, sort by the contents of the stack trace, which we assume to be whatever is after the first line. [seanga2@gmail.com: fix NULL-pointer dereference when comparing stack traces] Link: https://lkml.kernel.org/r/20211125162653.1855958-1-seanga2@gmail.com Link: https://lkml.kernel.org/r/20211124193709.1805776-1-seanga2@gmail.com Signed-off-by: -
Linus Torvalds authored
Merge more updates from Andrew Morton: "Various misc subsystems, before getting into the post-linux-next material. 41 patches. Subsystems affected by this patch series: procfs, misc, core-kernel, lib, checkpatch, init, pipe, minix, fat, cgroups, kexec, kdump, taskstats, panic, kcov, resource, and ubsan" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (41 commits) Revert "ubsan, kcsan: Don't combine sanitizer with kcov on clang" kernel/resource: fix kfree() of bootmem memory again kcov: properly handle subsequent mmap calls kcov: split ioctl handling into locked and unlocked parts panic: move panic_print before kmsg dumpers panic: add option to dump all CPUs backtraces in panic_print docs: sysctl/kernel: add missing bit to panic_print taskstats: remove unneeded dead assignment kasan: no need to unset panic_on_warn in end_report() ubsan: no need to unset panic_on_warn in ubsan_epilogue() panic: unset panic_on_war...
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git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextLinus Torvalds authored
Pull networking updates from Jakub Kicinski: "The sprinkling of SPI drivers is because we added a new one and Mark sent us a SPI driver interface conversion pull request. Core ---- - Introduce XDP multi-buffer support, allowing the use of XDP with jumbo frame MTUs and combination with Rx coalescing offloads (LRO). - Speed up netns dismantling (5x) and lower the memory cost a little. Remove unnecessary per-netns sockets. Scope some lists to a netns. Cut down RCU syncing. Use batch methods. Allow netdev registration to complete out of order. - Support distinguishing timestamp types (ingress vs egress) and maintaining them across packet scrubbing points (e.g. redirect). - Continue the work of annotating packet drop reasons throughout the stack. - Switch netdev error counters from an atomic to dynamically allocated per-CPU counters. - Rework a few preempt_disable(), local_irq_save() and busy waiting sections problematic on PREEMPT_RT. - Extend the ref_tracker to allow catching use-after-free bugs. BPF --- - Introduce "packing allocator" for BPF JIT images. JITed code is marked read only, and used to be allocated at page granularity. Custom allocator allows for more efficient memory use, lower iTLB pressure and prevents identity mapping huge pages from getting split. - Make use of BTF type annotations (e.g. __user, __percpu) to enforce the correct probe read access method, add appropriate helpers. - Convert the BPF preload to use light skeleton and drop the user-mode-driver dependency. - Allow XDP BPF_PROG_RUN test infra to send real packets, enabling its use as a packet generator. - Allow local storage memory to be allocated with GFP_KERNEL if called from a hook allowed to sleep. - Introduce fprobe (multi kprobe) to speed up mass attachment (arch bits to come later). - Add unstable conntrack lookup helpers for BPF by using the BPF kfunc infra. - Allow cgroup BPF progs to return custom errors to user space. - Add support for AF_UNIX iterator batching. - Allow iterator programs to use sleepable helpers. - Support JIT of add, and, or, xor and xchg atomic ops on arm64. - Add BTFGen support to bpftool which allows to use CO-RE in kernels without BTF info. - Large number of libbpf API improvements, cleanups and deprecations. Protocols --------- - Micro-optimize UDPv6 Tx, gaining up to 5% in test on dummy netdev. - Adjust TSO packet sizes based on min_rtt, allowing very low latency links (data centers) to always send full-sized TSO super-frames. - Make IPv6 flow label changes (AKA hash rethink) more configurable, via sysctl and setsockopt. Distinguish between server and client behavior. - VxLAN support to "collect metadata" devices to terminate only configured VNIs. This is similar to VLAN filtering in the bridge. - Support inserting IPv6 IOAM information to a fraction of frames. - Add protocol attribute to IP addresses to allow identifying where given address comes from (kernel-generated, DHCP etc.) - Support setting socket and IPv6 options via cmsg on ping6 sockets. - Reject mis-use of ECN bits in IP headers as part of DSCP/TOS. Define dscp_t and stop taking ECN bits into account in fib-rules. - Add support for locked bridge ports (for 802.1X). - tun: support NAPI for packets received from batched XDP buffs, doubling the performance in some scenarios. - IPv6 extension header handling in Open vSwitch. - Support IPv6 control message load balancing in bonding, prevent neighbor solicitation and advertisement from using the wrong port. Support NS/NA monitor selection similar to existing ARP monitor. - SMC - improve performance with TCP_CORK and sendfile() - support auto-corking - support TCP_NODELAY - MCTP (Management Component Transport Protocol) - add user space tag control interface - I2C binding driver (as specified by DMTF DSP0237) - Multi-BSSID beacon handling in AP mode for WiFi. - Bluetooth: - handle MSFT Monitor Device Event - add MGMT Adv Monitor Device Found/Lost events - Multi-Path TCP: - add support for the SO_SNDTIMEO socket option - lots of selftest cleanups and improvements - Increase the max PDU size in CAN ISOTP to 64 kB. Driver API ---------- - Add HW counters for SW netdevs, a mechanism for devices which offload packet forwarding to report packet statistics back to software interfaces such as tunnels. - Select the default NIC queue count as a fraction of number of physical CPU cores, instead of hard-coding to 8. - Expose devlink instance locks to drivers. Allow device layer of drivers to use that lock directly instead of creating their own which always runs into ordering issues in devlink callbacks. - Add header/data split indication to guide user space enabling of TCP zero-copy Rx. - Allow configuring completion queue event size. - Refactor page_pool to enable fragmenting after allocation. - Add allocation and page reuse statistics to page_pool. - Improve Multiple Spanning Trees support in the bridge to allow reuse of topologies across VLANs, saving HW resources in switches. - DSA (Distributed Switch Architecture): - replay and offload of host VLAN entries - offload of static and local FDB entries on LAG interfaces - FDB isolation and unicast filtering New hardware / drivers ---------------------- - Ethernet: - LAN937x T1 PHYs - Davicom DM9051 SPI NIC driver - Realtek RTL8367S, RTL8367RB-VB switch and MDIO - Microchip ksz8563 switches - Netronome NFP3800 SmartNICs - Fungible SmartNICs - MediaTek MT8195 switches - WiFi: - mt76: MediaTek mt7916 - mt76: MediaTek mt7921u USB adapters - brcmfmac: Broadcom BCM43454/6 - Mobile: - iosm: Intel M.2 7360 WWAN card Drivers ------- - Convert many drivers to the new phylink API built for split PCS designs but also simplifying other cases. - Intel Ethernet NICs: - add TTY for GNSS module for E810T device - improve AF_XDP performance - GTP-C and GTP-U filter offload - QinQ VLAN support - Mellanox Ethernet NICs (mlx5): - support xdp->data_meta - multi-buffer XDP - offload tc push_eth and pop_eth actions - Netronome Ethernet NICs (nfp): - flow-independent tc action hardware offload (police / meter) - AF_XDP - Other Ethernet NICs: - at803x: fiber and SFP support - xgmac: mdio: preamble suppression and custom MDC frequencies - r8169: enable ASPM L1.2 if system vendor flags it as safe - macb/gem: ZynqMP SGMII - hns3: add TX push mode - dpaa2-eth: software TSO - lan743x: multi-queue, mdio, SGMII, PTP - axienet: NAPI and GRO support - Mellanox Ethernet switches (mlxsw): - source and dest IP address rewrites - RJ45 ports - Marvell Ethernet switches (prestera): - basic routing offload - multi-chain TC ACL offload - NXP embedded Ethernet switches (ocelot & felix): - PTP over UDP with the ocelot-8021q DSA tagging protocol - basic QoS classification on Felix DSA switch using dcbnl - port mirroring for ocelot switches - Microchip high-speed industrial Ethernet (sparx5): - offloading of bridge port flooding flags - PTP Hardware Clock - Other embedded switches: - lan966x: PTP Hardward Clock - qca8k: mdio read/write operations via crafted Ethernet packets - Qualcomm 802.11ax WiFi (ath11k): - add LDPC FEC type and 802.11ax High Efficiency data in radiotap - enable RX PPDU stats in monitor co-exist mode - Intel WiFi (iwlwifi): - UHB TAS enablement via BIOS - band disablement via BIOS - channel switch offload - 32 Rx AMPDU sessions in newer devices - MediaTek WiFi (mt76): - background radar detection - thermal management improvements on mt7915 - SAR support for more mt76 platforms - MBSSID and 6 GHz band on mt7915 - RealTek WiFi: - rtw89: AP mode - rtw89: 160 MHz channels and 6 GHz band - rtw89: hardware scan - Bluetooth: - mt7921s: wake on Bluetooth, SCO over I2S, wide-band-speed (WBS) - Microchip CAN (mcp251xfd): - multiple RX-FIFOs and runtime configurable RX/TX rings - internal PLL, runtime PM handling simplification - improve chip detection and error handling after wakeup" * tag 'net-next-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2521 commits) llc: fix netdevice reference leaks in llc_ui_bind() drivers: ethernet: cpsw: fix panic when interrupt coaleceing is set via ethtool ice: don't allow to run ice_send_event_to_aux() in atomic ctx ice: fix 'scheduling while atomic' on aux critical err interrupt net/sched: fix incorrect vlan_push_eth dest field net: bridge: mst: Restrict info size queries to bridge ports net: marvell: prestera: add missing destroy_workqueue() in prestera_module_init() drivers: net: xgene: Fix regression in CRC stripping net: geneve: add missing netlink policy and size for IFLA_GENEVE_INNER_PROTO_INHERIT net: dsa: fix missing host-filtered multicast addresses net/mlx5e: Fix build warning, detected write beyond size of field iwlwifi: mvm: Don't fail if PPAG isn't supported selftests/bpf: Fix kprobe_multi test. Revert "rethook: x86: Add rethook x86 implementation" Revert "arm64: rethook: Add arm64 rethook implementation" Revert "powerpc: Add rethook support" Revert "ARM: rethook: Add rethook arm implementation" netdevice: add missing dm_private kdoc net: bridge: mst: prevent NULL deref in br_mst_info_size() selftests: forwarding: Use same VRF for port and VLAN upper ... -
https://github.com/awilliam/linux-vfioLinus Torvalds authored
Pull VFIO updates from Alex Williamson: - Introduce new device migration uAPI and implement device specific mlx5 vfio-pci variant driver supporting new protocol (Jason Gunthorpe, Yishai Hadas, Leon Romanovsky) - New HiSilicon acc vfio-pci variant driver, also supporting migration interface (Shameer Kolothum, Longfang Liu) - D3hot fixes for vfio-pci-core (Abhishek Sahu) - Document new vfio-pci variant driver acceptance criteria (Alex Williamson) - Fix UML build unresolved ioport_{un}map() functions (Alex Williamson) - Fix MAINTAINERS due to header movement (Lukas Bulwahn) * tag 'vfio-v5.18-rc1' of https://github.com/awilliam/linux-vfio: (31 commits) vfio-pci: Provide reviewers and acceptance criteria for variant drivers MAINTAINERS: adjust entry for header movement in hisilicon qm driver hisi_acc_vfio_pci: Use its own PCI reset_done error handler hisi_acc_vfio_pci: Add support for VFIO live migration crypto: hisilicon/qm: Set the VF QM state register hisi_acc_vfio_pci: Add helper to retrieve the struct pci_driver hisi_acc_vfio_pci: Restrict access to VF dev BAR2 migration region hisi_acc_vfio_pci: add new vfio_pci driver for HiSilicon ACC devices hisi_acc_qm: Move VF PCI device IDs to common header crypto: hisilicon/qm: Move few definitions to common header crypto: hisilicon/qm: Move the QM header to include/linux vfio/mlx5: Fix to not use 0 as NULL pointer PCI/IOV: Fix wrong kernel-doc identifier vfio/mlx5: Use its own PCI reset_done error handler vfio/pci: Expose vfio_pci_core_aer_err_detected() vfio/mlx5: Implement vfio_pci driver for mlx5 devices vfio/mlx5: Expose migration commands over mlx5 device vfio: Remove migration protocol v1 documentation vfio: Extend the device migration protocol with RUNNING_P2P vfio: Define device migration protocol v2 ... -
Linus Torvalds authored
Merge tag 'hyperv-next-signed-20220322' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux Pull hyperv updates from Wei Liu: "Minor patches from various people" * tag 'hyperv-next-signed-20220322' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: x86/hyperv: Output host build info as normal Windows version number hv_balloon: rate-limit "Unhandled message" warning drivers: hv: log when enabling crash_kexec_post_notifiers hv_utils: Add comment about max VMbus packet size in VSS driver Drivers: hv: Compare cpumasks and not their weights in init_vp_index() Drivers: hv: Rename 'alloced' to 'allocated' Drivers: hv: vmbus: Use struct_size() helper in kmalloc()
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git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds authored
Pull kvm updates from Paolo Bonzini: "ARM: - Proper emulation of the OSLock feature of the debug architecture - Scalibility improvements for the MMU lock when dirty logging is on - New VMID allocator, which will eventually help with SVA in VMs - Better support for PMUs in heterogenous systems - PSCI 1.1 support, enabling support for SYSTEM_RESET2 - Implement CONFIG_DEBUG_LIST at EL2 - Make CONFIG_ARM64_ERRATUM_2077057 default y - Reduce the overhead of VM exit when no interrupt is pending - Remove traces of 32bit ARM host support from the documentation - Updated vgic selftests - Various cleanups, doc updates and spelling fixes RISC-V: - Prevent KVM_COMPAT from being selected - Optimize __kvm_riscv_switch_to() implementation - RISC-V SBI v0.3 support s390: - memop selftest - fix SCK locking - adapter interruptions virtualization for secure guests - add Claudio Imbrenda as maintainer - first step to do proper storage key checking x86: - Continue switching kvm_x86_ops to static_call(); introduce static_call_cond() and __static_call_ret0 when applicable. - Cleanup unused arguments in several functions - Synthesize AMD 0x80000021 leaf - Fixes and optimization for Hyper-V sparse-bank hypercalls - Implement Hyper-V's enlightened MSR bitmap for nested SVM - Remove MMU auditing - Eager splitting of page tables (new aka "TDP" MMU only) when dirty page tracking is enabled - Cleanup the implementation of the guest PGD cache - Preparation for the implementation of Intel IPI virtualization - Fix some segment descriptor checks in the emulator - Allow AMD AVIC support on systems with physical APIC ID above 255 - Better API to disable virtualization quirks - Fixes and optimizations for the zapping of page tables: - Zap roots in two passes, avoiding RCU read-side critical sections that last too long for very large guests backed by 4 KiB SPTEs. - Zap invalid and defunct roots asynchronously via concurrency-managed work queue. - Allowing yielding when zapping TDP MMU roots in response to the root's last reference being put. - Batch more TLB flushes with an RCU trick. Whoever frees the paging structure now holds RCU as a proxy for all vCPUs running in the guest, i.e. to prolongs the grace period on their behalf. It then kicks the the vCPUs out of guest mode before doing rcu_read_unlock(). Generic: - Introduce __vcalloc and use it for very large allocations that need memcg accounting" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (246 commits) KVM: use kvcalloc for array allocations KVM: x86: Introduce KVM_CAP_DISABLE_QUIRKS2 kvm: x86: Require const tsc for RT KVM: x86: synthesize CPUID leaf 0x80000021h if useful KVM: x86: add support for CPUID leaf 0x80000021 KVM: x86: do not use KVM_X86_OP_OPTIONAL_RET0 for get_mt_mask Revert "KVM: x86/mmu: Zap only TDP MMU leafs in kvm_zap_gfn_range()" kvm: x86/mmu: Flush TLB before zap_gfn_range releases RCU KVM: arm64: fix typos in comments KVM: arm64: Generalise VM features into a set of flags KVM: s390: selftests: Add error memop tests KVM: s390: selftests: Add more copy memop tests KVM: s390: selftests: Add named stages for memop test KVM: s390: selftests: Add macro as abstraction for MEM_OP KVM: s390: selftests: Split memop tests KVM: s390x: fix SCK locking RISC-V: KVM: Implement SBI HSM suspend call RISC-V: KVM: Add common kvm_riscv_vcpu_wfi() function RISC-V: Add SBI HSM suspend related defines RISC-V: KVM: Implement SBI v0.3 SRST extension ... -
git://git.osdn.net/gitroot/tomoyo/tomoyo-test1Linus Torvalds authored
Pull tomoyo update from Tetsuo Handa: "Avoid unnecessarily leaking kernel command line arguments" * tag 'tomoyo-pr-20220322' of git://git.osdn.net/gitroot/tomoyo/tomoyo-test1: TOMOYO: fix __setup handlers return values
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Linus Torvalds authored
Merge tag 'flexible-array-transformations-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux Pull flexible-array transformations from Gustavo Silva: "Treewide patch that replaces zero-length arrays with flexible-array members. This has been baking in linux-next for a whole development cycle" * tag 'flexible-array-transformations-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux: treewide: Replace zero-length arrays with flexible-array members
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Linus Torvalds authored
Merge tag 'prlimit-tasklist_lock-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull tasklist_lock optimizations from Eric Biederman: "prlimit and getpriority tasklist_lock optimizations The tasklist_lock popped up as a scalability bottleneck on some testing workloads. The readlocks in do_prlimit and set/getpriority are not necessary in all cases. Based on a cycles profile, it looked like ~87% of the time was spent in the kernel, ~42% of which was just trying to get *some* spinlock (queued_spin_lock_slowpath, not necessarily the tasklist_lock). The big offenders (with rough percentages in cycles of the overall trace): - do_wait 11% - setpriority 8% (done previously in commit 7f8ca0ed) - kill 8% - do_exit 5% - clone 3% - prlimit64 2% (this patchset) - getrlimit 1% (this patchset) I can't easily test this patchset on the original workload for various reasons. Instead, I used the microbenchmark below to at least verify there was some improvement. This patchset had a 28% speedup (12% from baseline to set/getprio, then another 14% for prlimit). This series used to do the setpriority case, but an almost identical change was merged as commit 7f8ca0ed ("kernel/sys.c: only take tasklist_lock for get/setpriority(PRIO_PGRP)") so that has been dropped from here. One interesting thing is that my libc's getrlimit() was calling prlimit64, so hoisting the read_lock(tasklist_lock) into sys_prlimit64 had no effect - it essentially optimized the older syscalls only. I didn't do that in this patchset, but figured I'd mention it since it was an option from the previous patch's discussion" micobenchmark.c: --------------- int main(int argc, char **argv) { pid_t child; struct rlimit rlim[1]; fork(); fork(); fork(); fork(); fork(); fork(); for (int i = 0; i < 5000; i++) { child = fork(); if (child < 0) exit(1); if (child > 0) { usleep(1000); kill(child, SIGTERM); waitpid(child, NULL, 0); } else { for (;;) { setpriority(PRIO_PROCESS, 0, getpriority(PRIO_PROCESS, 0)); getrlimit(RLIMIT_CPU, rlim); } } } return 0; } Link: https://lore.kernel.org/lkml/20211213220401.1039578-1-brho@google.com/ [v1] Link: https://lore.kernel.org/lkml/20220105212828.197013-1-brho@google.com/ [v2] Link: https://lore.kernel.org/lkml/20220106172041.522167-1-brho@google.com/ [v3] * tag 'prlimit-tasklist_lock-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: prlimit: do not grab the tasklist_lock prlimit: make do_prlimit() static
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git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linuxLinus Torvalds authored
Pull mount attributes PREEMPT_RT update from Christian Brauner: "This contains Sebastian's fix to make changing mount attributes/getting write access compatible with CONFIG_PREEMPT_RT. The change only applies when users explicitly opt-in to real-time via CONFIG_PREEMPT_RT otherwise things are exactly as before. We've waited quite a long time with this to make sure folks could take a good look" * tag 'fs.rt.v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: fs/namespace: Boost the mount_lock.lock owner instead of spinning on PREEMPT_RT.
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git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linuxLinus Torvalds authored
Pull mount_setattr updates from Christian Brauner: "This contains a few more patches to massage the mount_setattr() codepaths and one minor fix to reuse a helper we added some time back. The final two patches do similar cleanups in different ways. One patch is mine and the other is Al's who was nice enough to give me a branch for it. Since his came in later and my branch had been sitting in -next for quite some time we just put his on top instead of swap them" * tag 'fs.v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: mount_setattr(): clean the control flow and calling conventions fs: clean up mount_setattr control flow fs: don't open-code mnt_hold_writers() fs: simplify check in mount_setattr_commit() fs: add mnt_allow_writers() and simplify mount_setattr_prepare()
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