823f53a30e
Kernel uses __kvm_riscv_switch_to() and __kvm_switch_return() to switch the context of host kernel and guest kernel. Several CSRs belonging to the context will be read and written during the context switch. To ensure atomic read-modify-write control of CSR and ordering of CSR accesses, some hardware blocks flush the pipeline when writing a CSR. In this circumstance, grouping CSR executions together as much as possible can reduce the performance impact of the pipeline. Therefore, this commit reorders the CSR instructions to enhance the context switch performance.. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Suggested-by: Hsinyi Lee <hsinyi.lee@sifive.com> Suggested-by: Fu-Ching Yang <fu-ching.yang@sifive.com> Signed-off-by: Anup Patel <anup@brainfault.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.