kernel

LKML News v6.8-rc4

[PATCH] mm/cma: Add sysfs file ‘release_pages_success’ (Anshuman Khandual) https://lkml.kernel.org/r/20240206045731.472759-1-anshuman.khandual@arm.com This patch adds a new sysfs file for tracking the number of successfully released pages from a given CMA heap area. It aims to be hulpful at determining available active CMA pages. [PATCH v2] mm/demotion: print demotion targets (Li Zhijian) https://lkml.kernel.org/r/20240206020151.605516-1-lizhijian@fujitsu.com Li Zhijian sent a patch for printing demotion target information in case of fallback for unmet requirements on the target node, directly to the kernel log.

LKML News v6.8-rc3

[GIT PULL] hotfixes for 6.8-rc3 (Andrew Morton) https://lkml.kernel.org/r/20240128232759.7535e6774bec152556fb9730@linux-foundation.org Andrew Morton sent a hotfixes pull request to Linus Torvalds. [LSF/MM/BPF TOPIC] Reclaiming & documenting page flags (Matthew Wilcox) https://lkml.kernel.org/r/Zbcn-P4QKgBhyxdO@casper.infradead.org Matthew proposes yet another LSFMM topic for discussing what page flags actually mean altogether, for better documentation. [PATCH v7 0/1] mm: report per-page metadata information (Sourav Panda) https://lkml.kernel.org/r/20240129224204.1812062-1-souravpanda@google.com Sourav from Google posted a patch for adding a new field on /proc/meminfo and /sys/devices/system/node/nodeN/vmstat called PageMetadata and nr_page_metadata respectively, which can helps understand how much memory are being used for page metadata.

LKML News v6.8-rc2

Project: Improving the PCP allocator (Matthew Wilcox) https://lkml.kernel.org/r/Za6RXtSE_TSdrRm_@casper.infradead.org Matthew introduces an idea to improve the PCP allocator, roughly saying, keeping only compound memory on the PCP list. [PATCH v2 0/3] Enable >0 order folio memory compaction (Zi Yan) https://lkml.kernel.org/r/20240123034636.1095672-1-zi.yan@sent.com Zi enables larger than zero order folio compaction, which is the prerequisite for large folio support. [PATCH v2 1/3] mm: make vm_area_struct anon_name field RCU-safe (Suren Baghdasaryan) https://lkml.kernel.org/r/20240123231014.3801041-1-surenb@google.com For lockless /proc/pid/maps reads, this patch makes anon_name field of vm_area_struct, which is the only one field that need to be accessed for reading the file but not RCU-protected, to be protected by RCU.

LKML News v6.8-rc1

[GIT PULL] MM updates for 6.8-rc1 (Andrew Morton) https://lkml.kernel.org/r/20240108155039.fd2798712a2a93a108b710ce@linux-foundation.org/ Andrew Morton sent the memory management subsystem side pull request for Linux v6.8-rc1 to Linus Torvalds. The request has many interesting changes including zswap writeback improvement, Feedback-based DAMOS autotuning, Multi-size anon THP, KSM advisor and many more. [GIT PULL] non-MM updates for 6.8-rc1 (Andrew Morton) https://lkml.kernel.org/r/20240109110420.dcdefe80d76257d9ff645a32@linux-foundation.org Andrew sent yet another pull request for out of memory management subsystem changes to Linus Torvalds.

LKML News v6.7

[PATCH v3 0/7] hugetlb: parallelize hugetlb page init on boot (Gang Li) https://lkml.kernel.org/r/20240102131249.76622-1-gang.li@linux.dev The thrid version of hugetlb initialization prallelization patchset has posted. [PATCH v3 00/11] Mitigate a vmap lock contention v3 (Uladzislau Rezki) https://lkml.kernel.org/r/20240102184633.748113-1-urezki@gmail.com Third version of vmap lock contention mitigation patch has posted. [PATCH v6 0/2] Add swappiness argument to memory.reclaim (Dan Schatzberg) https://lkml.kernel.org/r/20240103164841.2800183-1-schatzberg.dan@gmail.com Sixth version of the patchset for letting memory.reclaim memcg file be used with swappiness argument has posted.

My opensource commits statistics in 2023

As today is the last day of 2023, I checked some open source commits statistics using my simple and buggy script, and github. Similar statistics for 2022 is available at another post. In short, I made 8th and 4th biggest changes to Linux kernel memory management subsystem among the 295 people, for lines of changes (1,910) and commits (66). For the Linux kernel whole tree, the numbers become 264th (3,562 lines) and 80th (147 commits) among 5,006 people.

LKML News v6.7-rc8

[PATCH] kernel: Introduce a write lock/unlock wrapper for tasklist_lock (Maria Yu) https://lkml.kernel.org/r/20231225081932.17752-1-quic_aiquny@quicinc.com A patch introducing a write lock/unlock wrapper for tasklist_lock, to overcome bad responsive performance of system that coming from scenarios that acquiring read lock which wrote lock needed to be waiting for. [PATCH v3 00/10] IOMMU memory observability (Pasha Tatashin) https://lkml.kernel.org/r/20231226200205.562565-1-pasha.tatashin@soleen.com Third version of patchset to allow monitoring and limiting IOMMU memory usage is posted. [GIT PULL] hotfixes for 6.

LKML News v6.7-rc7

[PATCH v5 0/4] mm/ksm: Add ksm advisor (Stefan Roesch) https://lkml.kernel.org/r/20231218231054.1625219-1-shr@devkernel.io Stefan posted the fifth version of the patchset for automatic and efficient tuning of kernel samepage merging. [PATCH -next v4 0/2] Make memory reclamation measurable (Bixuan Cui) https://lkml.kernel.org/r/20231220012123.2787-1-cuibixuan@vivo.com This patchset adds a new tracer to shrink_active_list(), shrink_inactive_list(), and shrinker->count_objects() to make memory recycling mesaurable with bpf. [RFC PATCH 1/1] mm: mark folio accessed in minor fault (Zhaoyang Huang) https://lkml.kernel.org/r/20231220102948.1963798-1-zhaoyang.huang@unisoc.com Inactive mapped folio is promoted to active only when it is scanned in shrink_inactive_list().

LKML News v6.7-rc6

[Invitation] Linux MM Alignment Session on remap_file_pages on Wednesday (David Rientjes) https://lkml.kernel.org/r/46f97bec-3a48-e714-0a8d-b5206e1704ba@google.com There will be the last Linux MM Alignment Session for re-introducing remap_file_pages(), led by Matthew Wilcox, on 2023-11-13. [PATCH] kernel: Introduce a write lock/unlock wrapper for tasklist_lock (Maria Yu) https://lkml.kernel.org/r/20231213101745.4526-1-quic_aiquny@quicinc.com There are multiple scenarios for tasklist_lock that could lead to bad responsiveness. To mitigate the situation, this patch introduces a write lock/unlock wrapper for tasklist_lock. [PATCH 0/9] Finish two folio conversions (Matthew Wilcox) https://lkml.

LKML News v6.7-rc5

[PATCH] mm/thp: add CONFIG_TRANSPARENT_HUGEPAGE_NEVER option (Dmytro Maluka) https://lkml.kernel.org/r/20231204163254.2636289-1-dmaluka@chromium.org Khugepaged has its own memory cost, and it increases vm.min_free_kbytes as it needs when it starts. On 4GB RAM, 3 mmzones and pageblock_order == MAX_ORDER, khugepaged increases vm.min_free_kbytes from 8MB to 132MB. This patch introduces a config to disallow khugepaged starts by default. It still allows the userspace to start khugepaged, though. [PATCH v4 0/2] KSM: support smart-scan feature (Stefan Roesch) https://lkml.kernel.org/r/20231205180952.3843711-1-shr@devkernel.io