news

LKML News v6.3-rc4

[PATCH 00/15] mm: move core MM initialization to mm/mm_init.c (Mike Rapoport) https://lkml.kernel.org/r/20230319220008.2138576-1-rppt@kernel.org This patchset consolidates MM initialization code to mm/mm_init.c file for better maintainability. [PATCH -next v6 0/2] Delay the initialization of zswap (Liu Shixin) https://lkml.kernel.org/r/20230322102006.780624-1-liushixin2@huawei.com This patchset delays zswap initialization until it gets enabled to save about 18MB of memory, which is allocated during the initialization. [PATCH V6 1/2] mm: compaction: move compaction sysctl to its own file (Minhao Chi) https://lkml.

LKML News v6.3-rc3

[LSF/MM/BPF TOPIC] SLOB+SLAB allocators removal and future SLUB improvements (Vlastimil Babka) https://lkml.kernel.org/r/4b9fc9c6-b48c-198f-5f80-811a44737e5f@suse.cz Linux kernel has three objects allocators, namely SLOB, SLAB, and SLUB. Vlastimil and many developers have tried to make it only one single allocator. Deprecation of SLOB has made some progress so far. Vlastimil proposes an LSF/MM/BPF topic for discussing deprecation of SLAB and SLUB futur eimprovement. [GIT PULL] hotfixes for 6.3-rc1 (Andrew Morton) https://lkml.kernel.org/r/20230314165437.a2d992731a970582fe36aaba@linux-foundation.org Yet another mm subsystem hotfixes pull request has sent to Linus Torvalds.

LKML News v6.3-rc2

[Invitation] Linux MM Alignment Session on Wednesday (David Rientjes) https://lkml.kernel.org/r/CAE-26VAFJtSu5xEbzNUgPVn3W13-B1bGvvU8-+i-hkS4GtupCw@mail.gmail.com David is hosting biweekly meetings for Linux memory management developments called Linux MM Alignment, and he is publicly inviting people to the meetings. The next instance will be held on 10:00 PST, 2023-03-08, at https://meet.google.com/csb-wcds-xya THP backed thread stacks (Mike Kravetz) https://lkml.kernel.org/r/20230306235730.GA31451@monkey Mike found THP-always’s memory bloat issue due to THP usage for threads’ stacks. Mike feels it might make no sense to use THP for stacks even if the THP policy is ‘always’, and starting discussions on improvment of the situation.

LKML News v6.3-rc1

[GIT PULL] MM updates for 6.3-rc1 (Andrew Morton) https://lkml.kernel.org/r/20230220135225.91b0f28344c01d5306c31230@linux-foundation.org The mm updates pull request for v6.3-rc1 has posted by Andrew. [GIT PULL] Compute Express Link (CXL) for 6.3 (Dan Williams) https://lkml.kernel.org/r/63f5a4e2277b1_c94229453@dwillia2-mobl3.amr.corp.intel.com.notmuch A pull request for makincg CXL handling including CXL memory layout parsing/updating and events/errors reporting has posted for v6.3. Without this patchset, currently the works are dependents on platform-firmware. [RFC v2 0/5] tmpfs: add the option to disable swap (Luis Chamberlain) https://lkml.

LKML News v6.2

[PATCH] mm/userfaultfd: Support operation on multiple VMAs (Muhammad Usama Anjum) https://lkml.kernel.org/r/20230213104323.1792839-1-usama.anjum@collabora.com mwriteprotect_range() handle only single VMA, but there are usecases which need to handle multiple VMAs in a memory range of interest. This commit fixes the case. [v2 PATCH 0/5] Introduce mempool pages bulk allocator and use it in dm-crypt (Yang Shi) https://lkml.kernel.org/r/20230214190221.1156876-1-shy828301@gmail.com Noticeable overhead on disc encryption due to page allocations have found. The overhead was because the allocation logic in dm-crypt allocates one page in each pass of a loop.

LKML News v6.2-rc8

[LSF/MM/BPF TOPIC] sframe: An orc like stack unwinder for the kernel to get a user space stacktrace (Steven Rostedt) https://lkml.kernel.org/r/20230206103828.6efcb28f@rorschach.local.home Steven Rostedt proposes yet another LSF/MM/BPF topic for using sframe section, which is introduced by binutils, for more efficient user space stack tracing. [PATCH v4 00/14] Introduce Copy-On-Write to Page Table (Chih-En Lin) https://lkml.kernel.org/r/20230207035139.272707-1-shiyn.lin@gmail.com Fourth version of the patchset making copy-on-write be used for page table, while it is currently only used for the mapped memory.

LKML News v6.2-rc7

[LSF/MM/BPF TOPIC] CXL Fabric Manager (FM) architecture (Viacheslav A.Dubeyko) https://lkml.kernel.org/r/7F001EAF-C512-436A-A9DD-E08730C91214@bytedance.com A topic suggestion for LSF/MM/BPF. It suggests to discuss about Fabric Manager (FM) architecture, which requires configuration tool, daemon, and QEMU emulation of CXL hardware features. [PATCH V2 0/3] sched/numa: Enhance vma scanning (Ragghavendra K T) https://lkml.kernel.org/r/cover.1675159422.git.raghavendra.kt@amd.com A patchset for improving access scanning for NUMA balancing. This uses per-thread VMA scanning idea from Mel. LSFMMBPF proposal [MM]: Lazy RCU memory reclaim (Joel Fernandes) https://lkml.

LKML News v6.2-rc6

[RFC PATCH 00/19] mm: Introduce a cgroup to limit the amount of locked and pinned memory (Alistair Popple) https://lkml.kernel.org/r/cover.f52b9eb2792bccb8a9ecd6bc95055705cfe2ae03.1674538665.git-series.apopple@nvidia.com This RFC patchset introduces a cgroup limit like RLIMIT_MEMLOCKED but that for pinned pages. [RFC PATCH 0/4] Fix excessive CPU usage during compaction (Mel Gorman) https://lkml.kernel.org/r/20230125134434.18017-1-mgorman@techsingularity.net A patch for not ignoring fast_find_migrateblock() found pageblocks made compaction shows high CPU and stalls. It therefore once merged in mainline, than reverted, and again merged in mm-unstable.

LKML News v6.2-rc5

[RFC] memory pressure detection in VMs using PSI mechanism for dynamically inflating/deflating VM memory (Sudarshan Rajagopalan) https://lkml.kernel.org/r/DS0PR02MB90787835F5B9CB9771A20329C4C09@DS0PR02MB9078.namprd02.prod.outlook.com Qualcomm’s Linux memory team asks upstream’s opinion about their userspace deamon approach for controlling VM memory size based on memory demands via monitoring PSI. [PATCH v1 0/3] Introduce per NUMA node memory error statistics (Jiaqi Yan) https://lkml.kernel.org/r/20230116193902.1315236-1-jiaqiyan@google.com On huge memory systems, memory error is inevitable, so detailed statistics of it helps administrators to operate systems more efficiently.

LKML News v6.2-rc4

[PATCH 00/41] Per-VMA locks (Suren Baghdasaryan) https://lkml.kernel.org/r/20230109205336.3665937-1-surenb@google.com For the mmap_lock scalability issue, yet another approach called per-VMA locks has posted. [PATCH v2 0/2] docs/mm: start filling out new structure (Mike Rapoport) https://lkml.kernel.org/r/20230110152358.2641910-1-rppt@kernel.org MM kernel documentation has restructured to be somewhat more like textbook that can better explaining overall concept and how it manage memory, but the content is empty. Mike starts filling the content. LSFMMBPF proposal [General/MM]: SRCU: a case study in memory ordering (Joel Fernandes) https://lkml.