For devices that support flushing, we allocate a bio, submit, wait for it and then free it. The bio allocation does not fail so ENOMEM is not a problem but we still may unnecessarily stress the allocation subsystem. Instead, we can allocate the bio at the same time we allocate the device and reuse it each time we need to flush the barriers. The bio is reset before each use. Reference counting is simplified to just device allocation (get) and freeing (put). The bio used to be submitted through the integrity checker which will find out that bio has no data attached and call submit_bio. Status of the bio in flight needs to be tracked separately in case the device caches get switched off between write and wait. Signed-off-by: David Sterba <dsterba@suse.com> |
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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.