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Linus Torvalds 70293240c5 Two regression fixes for the timer and timer migration code:
1) Prevent endless timer requeuing which is caused by two CPUs racing out
      of idle. This happens when the last CPU goes idle and therefore has to
      ensure to expire the pending global timers and some other CPU come out
      of idle at the same time and the other CPU wins the race and expires
      the global queue. This causes the last CPU to chase ghost timers
      forever and reprogramming it's clockevent device endlessly.
 
      Cure this by re-evaluating the wakeup time unconditionally.
 
   2) The split into local (pinned) and global timers in the timer wheel
      caused a regression for NOHZ full as it broke the idle tracking of
      global timers. On NOHZ full this prevents an self IPI being sent which
      in turn causes the timer to be not programmed and not being expired on
      time.
 
      Restore the idle tracking for the global timer base so that the self
      IPI condition for NOHZ full is working correctly again.
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Merge tag 'timers-urgent-2024-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer fixes from Thomas Gleixner:
 "Two regression fixes for the timer and timer migration code:

   - Prevent endless timer requeuing which is caused by two CPUs racing
     out of idle. This happens when the last CPU goes idle and therefore
     has to ensure to expire the pending global timers and some other
     CPU come out of idle at the same time and the other CPU wins the
     race and expires the global queue. This causes the last CPU to
     chase ghost timers forever and reprogramming it's clockevent device
     endlessly.

     Cure this by re-evaluating the wakeup time unconditionally.

   - The split into local (pinned) and global timers in the timer wheel
     caused a regression for NOHZ full as it broke the idle tracking of
     global timers. On NOHZ full this prevents an self IPI being sent
     which in turn causes the timer to be not programmed and not being
     expired on time.

     Restore the idle tracking for the global timer base so that the
     self IPI condition for NOHZ full is working correctly again"

* tag 'timers-urgent-2024-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timers: Fix removed self-IPI on global timer's enqueue in nohz_full
  timers/migration: Fix endless timer requeue after idle interrupts
2024-03-23 14:49:25 -07:00
arch powerpc updates for 6.9 #2 2024-03-23 09:21:26 -07:00
block vfs-6.9-rc1.fixes 2024-03-18 09:15:50 -07:00
certs This update includes the following changes: 2023-11-02 16:15:30 -10:00
crypto RISC-V Patches for the 6.9 Merge Window 2024-03-22 10:41:13 -07:00
Documentation A set of updates for clocksource and clockevent drivers: 2024-03-23 14:42:45 -07:00
drivers A set of updates for clocksource and clockevent drivers: 2024-03-23 14:42:45 -07:00
fs A patch to minimize blockage when processing very large batches of 2024-03-22 11:15:45 -07:00
include powerpc updates for 6.9 #2 2024-03-23 09:21:26 -07:00
init RISC-V Patches for the 6.9 Merge Window 2024-03-22 10:41:13 -07:00
io_uring io_uring/sqpoll: early exit thread if task_context wasn't allocated 2024-03-18 20:22:42 -06:00
ipc sysctl changes for v6.9-rc1 2024-03-18 14:59:13 -07:00
kernel Two regression fixes for the timer and timer migration code: 2024-03-23 14:49:25 -07:00
lib hardening fixes for v6.9-rc1 2024-03-23 08:43:21 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm RISC-V Patches for the 6.9 Merge Window 2024-03-22 10:41:13 -07:00
net Including fixes from CAN, netfilter, wireguard and IPsec. 2024-03-21 14:50:39 -07:00
rust Kbuild updates for v6.9 2024-03-21 14:41:00 -07:00
samples Tracing updates for 6.9: 2024-03-18 15:11:44 -07:00
scripts LoongArch changes for v6.9 2024-03-22 10:22:45 -07:00
security - Kuan-Wei Chiu has developed the well-named series "lib min_heap: Min 2024-03-14 18:03:09 -07:00
sound sound fixes #2 for 6.9-rc2 2024-03-22 09:44:19 -07:00
tools RISC-V Patches for the 6.9 Merge Window 2024-03-22 10:41:13 -07:00
usr Kbuild updates for v6.8 2024-01-18 17:57:07 -08:00
virt KVM Xen and pfncache changes for 6.9: 2024-03-11 10:42:55 -04:00
.clang-format clang-format: Update with v6.7-rc4's for_each macro list 2023-12-08 23:54:38 +01:00
.cocciconfig
.editorconfig Add .editorconfig file for basic formatting 2023-12-28 16:22:47 +09:00
.get_maintainer.ignore Add Jeff Kirsher to .get_maintainer.ignore 2024-03-08 11:36:54 +00:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore kbuild: create a list of all built DTB files 2024-02-19 18:20:39 +09:00
.mailmap Char/Misc and other driver subsystem updates for 6.9-rc1 2024-03-21 13:21:31 -07:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING
CREDITS Not a ton of stuff happening in the clk framework in this pull request. We got 2024-03-15 11:48:01 -07:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS RISC-V Patches for the 6.9 Merge Window 2024-03-22 10:41:13 -07:00
Makefile Kbuild updates for v6.9 2024-03-21 14:41:00 -07:00
README README: Fix spelling 2024-03-18 03:36:32 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.