The attached patch implements three optimizations: 1) Loops in flush_user_dcache_range_asm, flush_kernel_dcache_range_asm, purge_kernel_dcache_range_asm, flush_user_icache_range_asm, and flush_kernel_icache_range_asm are unrolled to reduce branch overhead. 2) The static branch prediction for cmpb instructions in pacache.S have been reviewed and the operand order adjusted where necessary. 3) For flush routines in cache.c, we purge rather flush when we have no context. The pdc instruction at level 0 is not required to write back dirty lines to memory. This provides a performance improvement over the fdc instruction if the feature is implemented. Version 2 adds alternative patching. The patch provides an average improvement of about 2%. Signed-off-by: John David Anglin <dave.anglin@bell.net> Signed-off-by: Helge Deller <deller@gmx.de> |
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Documentation | ||
LICENSES | ||
arch | ||
block | ||
certs | ||
crypto | ||
drivers | ||
firmware | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.clang-format | ||
.cocciconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
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 Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. 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.