Kernel for Galaxy S24, rebased on CLO sources (WIP)
Right now we punt any buffered request that ends up triggering an -EAGAIN to an async workqueue. This works fine in terms of providing async execution of them, but it also can create quite a lot of work queue items. For sequentially buffered IO, it's advantageous to serialize the issue of them. For reads, the first one will trigger a read-ahead, and subsequent request merely end up waiting on later pages to complete. For writes, devices usually respond better to streamed sequential writes. Add state to track the last buffered request we punted to a work queue, and if the next one is sequential to the previous, attempt to get the previous work item to handle it. We limit the number of sequential add-ons to the a multiple (8) of the max read-ahead size of the file. This should be a good number for both reads and wries, as it defines the max IO size the device can do directly. This drastically cuts down on the number of context switches we need to handle buffered sequential IO, and a basic test case of copying a big file with io_uring sees a 5x speedup. Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> |
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arch | ||
block | ||
certs | ||
crypto | ||
Documentation | ||
drivers | ||
firmware | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
LICENSES | ||
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 |
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.