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Uros Bizjak 58b4fba81a ucount: use atomic_long_try_cmpxchg() in atomic_long_inc_below()
Use atomic_long_try_cmpxchg() instead of
atomic_long_cmpxchg (*ptr, old, new) == old in atomic_long_inc_below().
x86 CMPXCHG instruction returns success in ZF flag, so this change saves
a compare after cmpxchg (and related move instruction in front of cmpxchg).

Also, atomic_long_try_cmpxchg implicitly assigns old *ptr value to "old"
when cmpxchg fails, enabling further code simplifications.

No functional change intended.

Link: https://lkml.kernel.org/r/20250721174610.28361-2-ubizjak@gmail.com
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Reviewed-by: Alexey Gladkov <legion@kernel.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Alexey Gladkov <legion@kernel.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: MengEn Sun <mengensun@tencent.com>
Cc: "Thomas Weißschuh" <linux@weissschuh.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-08-02 12:01:38 -07:00
Documentation stackdepot: make max number of pools boot-time configurable 2025-08-02 12:01:38 -07:00
LICENSES LICENSES: add CC0-1.0 license text 2025-05-21 14:54:17 +02:00
arch kexec: enable CMA based contiguous allocation 2025-08-02 12:01:38 -07:00
block block-6.16-20250626 2025-06-27 09:02:33 -07:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto lib/raid6: replace custom zero page with ZERO_PAGE 2025-07-09 22:57:54 -07:00
drivers relayfs: abolish prev_padding 2025-07-09 22:57:51 -07:00
fs ocfs2: avoid potential ABBA deadlock by reordering tl_inode lock 2025-07-19 19:08:27 -07:00
include kexec: enable CMA based contiguous allocation 2025-08-02 12:01:38 -07:00
init init/Kconfig: restore CONFIG_BROKEN help text 2025-08-02 12:01:37 -07:00
io_uring io_uring-6.16-20250630 2025-06-30 16:32:43 -07:00
ipc - The 3 patch series "hung_task: extend blocking task stacktrace dump to 2025-05-31 19:12:53 -07:00
kernel ucount: use atomic_long_try_cmpxchg() in atomic_long_inc_below() 2025-08-02 12:01:38 -07:00
lib stackdepot: make max number of pools boot-time configurable 2025-08-02 12:01:38 -07:00
mm vfs-6.16-rc5.fixes 2025-07-04 09:06:49 -07:00
net Including fixes from Bluetooth. 2025-07-03 09:18:55 -07:00
rust Driver core fixes for 6.16-rc3 2025-06-18 14:31:16 -07:00
samples samples: enhance hung_task detector test with read-write semaphore support 2025-07-19 19:08:26 -07:00
scripts coccinelle: misc: secs_to_jiffies: implement context and report modes 2025-07-19 19:08:25 -07:00
security selinux: change security_compute_sid to return the ssid or tsid on match 2025-06-19 16:13:16 -04:00
sound ALSA: hda/realtek: Fix built-in mic on ASUS VivoBook X507UAR 2025-06-26 08:02:44 +02:00
tools delaytop: add psi info to show system delay 2025-07-19 19:08:29 -07:00
usr usr/include: openrisc: don't HDRTEST bpf_perf_event.h 2025-05-12 15:03:17 +09:00
virt Merge branch 'kvm-lockdep-common' into HEAD 2025-05-28 06:29:17 -04:00
.clang-format Linux 6.15-rc5 2025-05-06 16:39:25 +10:00
.clippy.toml rust: clean Rust 1.88.0's warning about `clippy::disallowed_macros` configuration 2025-05-07 00:11:47 +02:00
.cocciconfig
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: Retire Ralf Baechle 2024-11-12 15:48:59 +01:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore .gitignore: ignore Python compiled bytecode 2025-04-24 10:12:46 -06:00
.mailmap mailmap: update Sachin Mokashi's email address 2025-07-09 22:57:56 -07:00
.pylintrc docs: add a .pylintrc file with sys path for docs scripts 2025-04-09 12:10:33 -06:00
.rustfmt.toml
COPYING
CREDITS CREDITS: Add entry for Shannon Nelson 2025-06-21 07:34:28 -07:00
Kbuild drm: ensure drm headers are self-contained and pass kernel-doc 2025-02-12 10:44:43 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS MAINTAINERS: add lib/raid6/ to "SOFTWARE RAID" 2025-07-09 22:57:55 -07:00
Makefile Linux 6.16-rc5 2025-07-06 14:10:26 -07:00
README README: Fix spelling 2024-03-18 03:36:32 -06:00

README

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.