mainlining shenanigans
For write-behind mode, we think write IO is complete once it has reached all the non-writemostly devices. It works fine for single queue devices. But for multiqueue device, if there are lots of IOs come from upper layer, then the write-behind device could issue those IOs to different queues, depends on the each queue's delay, so there is no guarantee that those IOs can arrive in order. To address the issue, we need to check the collision among write behind IOs, we can only continue without collision, otherwise wait for the completion of previous collisioned IO. And WBCollision is introduced for multiqueue device which is worked under write-behind mode. But this patch doesn't handle below cases which could have the data inconsistency issue as well, these cases will be handled in later patches. 1. modify max_write_behind by write backlog node. 2. add or remove array's bitmap dynamically. 3. the change of member disk. Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Song Liu <songliubraving@fb.com> |
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arch | ||
block | ||
certs | ||
crypto | ||
Documentation | ||
drivers | ||
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.