491bd4d7aa
commit 455f9075f14484f358b3c1d6845b4a438de198a7 upstream. When the BIOS configures the architectural TSC-adjust MSRs on secondary sockets to correct a constant inter-chassis offset, after Linux brings the cores online, the TSC sync check later resets the core-local MSR to 0, triggering HPET fallback and leading to performance loss. Fix this by unconditionally using the initial adjust values read from the MSRs. Trusting the initial offsets in this architectural mechanism is a better approach than special-casing workarounds for specific platforms. Signed-off-by: Daniel J Blueman <daniel@quora.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Steffen Persvold <sp@numascale.com> Reviewed-by: James Cleverdon <james.cleverdon.external@eviden.com> Reviewed-by: Dimitri Sivanich <sivanich@hpe.com> Reviewed-by: Prarit Bhargava <prarit@redhat.com> Link: https://lore.kernel.org/r/20240419085146.175665-1-daniel@quora.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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.