LKML News v5.15-rc5

[PATCH 0/2] Introduce simple pidfd to task helper (Christian Brauner)

https://lkml.kernel.org/r/20211004125050.1153693-1-christian.brauner@ubuntu.com

This patchset adds a pidfd handling wrapper for removing duplications.

[PATCH 00/62] Separate struct slab from struct page (Matthew Wilcox)

https://lkml.kernel.org/r/20211004134650.4031813-1-willy@infradead.org

This huge patchset separates struct slab from struct page to make struct page simple and therefore easier to handle.

[PATCH v3 00/66] Introducing the Maple Tree (Liam Howlett)

https://lkml.kernel.org/r/20211005012959.1110504-1-Liam.Howlett@oracle.com

This patchset introduces Maple tree, which is intended to replace the rb tree for vmas, to improve the scalability.

mmotm 2021-10-05-19-53 uploaded (Andrew Morton)

https://lkml.kernel.org/r/20211006025350.a5PczFZP4%akpm@linux-foundation.org

MMOTM updated. 11 patches drop, 47 patches added, and 29 patches modified. DAMOS also added here.

[RFC] pgflags_t (Matthew Wilcox)

https://lkml.kernel.org/r/YV25hsgfJ2qAYiRJ@casper.infradead.org

This patch makes struct page->flags a struct instead of the plain unsigned long for enhance its type safety.

Compaction & folios (Ken Overstreet)

https://lkml.kernel.org/r/YV4o9SxfYuLm1i4d@moria.home.lan

This mail explains how folios can make compaction and hugepages easier.

[PATCH v2] mm/huge_memory.c: disable THP with large THP size on small present memory (Peng Hao)

https://lkml.kernel.org/r/CAPm50aLPxJCiVTqqwiz00oMNiqHggB84sXB3x=tv_HUAd5UktQ@mail.gmail.com

min_free_kbytes is calculated based on THP size. Because THP size could be quite big depends on the system configuration, min_free_kbytes could also be huge. For example, on ARM64 with 64 KiB page size, THP is 512 MiB and the min_free_kbytes is about 3 GiB.

This commit therefore judge if THP should be enabled or not by default using the THP size.

[PATCH -V9 0/6] NUMA balancing: optimize memory placement for memory tiering system (Huang Ying)

https://lkml.kernel.org/r/20211008083938.1702663-1-ying.huang@intel.com

Nineth revision of NUMA balancing for tiered memory system. This patchset applies the basic NUMA balancing, hot page selection algorithm, and automatic threshold adjustment step by step.

[PATCH 0/3] mm, thp: introduce a new sysfs interface to facilitate file THP for .text (Rongwei Wang)

https://lkml.kernel.org/r/20211009092658.59665-1-rongwei.wang@linux.alibaba.com

This patchset adds a new THP interface called hugetext_enabled for easier enablement of THP for text sections of processes, and make binaries built with --pie -fPIC and LOAD alignment smaller than 2M, change maximum_alignment to 2M, for making those better at applying THP.

Linux 5.15-rc5 (Linus Torvalds)

https://lkml.kernel.org/r/CAHk-=wiTZxkHVg=Pz7XRd-9AEDp0qV5sWmQJWnQ4NrSPYRHNiA@mail.gmail.com

The fifth release candidate for v5.15 is released. Just a normal one.

Below is the diffstat of the releases in the last two years.

Note that the y-axis is in logarithm. I draw it using https://github.com/sjp38/relstat and https://github.com/sjp38/lazybox using below command:

$ relstat.py --since 2019-10-11 | ~/lazybox/gnuplot/plot.py \
    --data_fmt table --type labeled-lines --xtics_rotate -90 \
    --font "Times New Roman, 5pt" --ylog --pointsize 0.3

And, below is the diffstat of the -rc5 releases in the last two years.