aee98a6838
Use try_cmpxchg64 instead of cmpxchg64 (*ptr, old, new) != old in tdp_mmu_set_spte_atomic. cmpxchg returns success in ZF flag, so this change saves a compare after cmpxchg (and related move instruction in front of cmpxchg). Also, remove explicit assignment to iter->old_spte when cmpxchg fails, this is what try_cmpxchg does implicitly. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Reviewed-by: David Matlack <dmatlack@google.com> Message-Id: <20220518135111.3535-1-ubizjak@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.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 Restructured Text 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.