Fork of alistair23 Linux kernel for reMarkable from https://github.com/alistair23/linux
27c539aeff
To prevent unnecessary branching, mark the exit condition of the primary loop as likely(), given that a carry in a 32-bit counter occurs very rarely. On arm64, the resulting code is emitted by GCC as 9a8: cmp w1, #0x3 9ac: add x3, x0, w1, uxtw 9b0: b.ls 9e0 <crypto_inc+0x38> 9b4: ldr w2, [x3,#-4]! 9b8: rev w2, w2 9bc: add w2, w2, #0x1 9c0: rev w4, w2 9c4: str w4, [x3] 9c8: cbz w2, 9d0 <crypto_inc+0x28> 9cc: ret where the two remaining branch conditions (one for size < 4 and one for the carry) are statically predicted as non-taken, resulting in optimal execution in the vast majority of cases. Also, replace the open coded alignment test with IS_ALIGNED(). Cc: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> |
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Documentation | ||
arch | ||
block | ||
certs | ||
crypto | ||
drivers | ||
firmware | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.cocciconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
README
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. 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.