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87347f1480
Optimize get_inode_sequence_number() to use simpler and faster: !atomic64_try_cmpxchg_relaxed(*ptr, &old, new) instead of: atomic64_cmpxchg relaxed(*ptr, old, new) != old The x86 CMPXCHG instruction returns success in ZF flag, so this change saves a compare after cmpxchg. The generated code improves from: 3da: 31 c0 xor %eax,%eax 3dc: f0 48 0f b1 8a 38 01 lock cmpxchg %rcx,0x138(%rdx) 3e3: 00 00 3e5: 48 85 c0 test %rax,%rax 3e8: 48 0f 44 c1 cmove %rcx,%rax to: 3da: 31 c0 xor %eax,%eax 3dc: f0 48 0f b1 8a 38 01 lock cmpxchg %rcx,0x138(%rdx) 3e3: 00 00 3e5: 48 0f 44 c1 cmove %rcx,%rax Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: André Almeida <andrealmeid@igalia.com> Link: https://lore.kernel.org/all/20241010071023.21913-2-ubizjak@gmail.com
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.