Kernel sources for Moto G9 (Play) (Guamp)
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Paolo Valente 4420b095cc block, bfq: do not expire a queue that will deserve dispatch plugging
For some bfq_queues, BFQ plugs I/O dispatching when the queue becomes
idle, and keeps the plug until a new request of the queue arrives, or
a timeout fires. BFQ does so either to boost throughput or to preserve
service guarantees for the queue.

More precisely, for such a queue, plugging starts when the queue
happens to have either no request enqueued, or no request in flight,
that is, no request already dispatched but not yet completed.

On the opposite end, BFQ may happen to expire a queue with no request
enqueued, without doing any plugging, if the queue still has some
request in flight. Unfortunately, such a premature expiration causes
the queue to lose its chance to enjoy dispatch plugging a moment
later, i.e., when its in-flight requests finally get completed. This
breaks service guarantees for the queue.

This commit prevents BFQ from expiring an empty queue if the latter
still has in-flight requests.

Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-09 09:07:52 -06:00
arch ARM: SoC fixes for 4.18-rc 2018-07-08 14:12:46 -07:00
block block, bfq: do not expire a queue that will deserve dispatch plugging 2018-07-09 09:07:52 -06:00
certs certs/blacklist: fix const confusion 2018-06-26 09:43:03 -07:00
crypto Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
Documentation USB fixes for 4.18-rc3 2018-07-01 11:50:16 -07:00
drivers ARM: SoC fixes for 4.18-rc 2018-07-08 14:12:46 -07:00
firmware
fs Bug fixes for ext4; most of which relate to vulnerabilities where a 2018-07-08 11:10:30 -07:00
include block: Make struct request_queue smaller for CONFIG_BLK_DEV_ZONED=n 2018-07-09 09:07:52 -06:00
init Kbuild fixes for v4.18 2018-06-30 13:05:30 -07:00
ipc ipc: use new return type vm_fault_t 2018-06-15 07:55:25 +09:00
kernel Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-07-08 12:41:23 -07:00
lib Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-07-02 11:18:28 -07:00
LICENSES LICENSES: Add Linux-OpenIB license text 2018-04-27 16:41:53 -06:00
mm mm: teach dump_page() to correctly output poisoned struct pages 2018-07-03 17:32:19 -07:00
net net/smc: fix up merge error with poll changes 2018-07-03 09:53:43 -07:00
samples VFIO fixes for v4.18 2018-07-06 12:23:53 -07:00
scripts Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-07-02 11:18:28 -07:00
security selinux/stable-4.18 PR 20180629 2018-06-30 11:15:12 -07:00
sound ALSA: seq: Fix UBSAN warning at SNDRV_SEQ_IOCTL_QUERY_NEXT_CLIENT ioctl 2018-06-25 11:18:04 +02:00
tools Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-07-08 11:57:40 -07:00
usr kbuild: rename built-in.o to built-in.a 2018-03-26 02:01:19 +09:00
virt KVM: arm64: Prevent KVM_COMPAT from being selected 2018-06-21 17:17:50 +01:00
.clang-format clang-format: add configuration file 2018-04-11 10:28:35 -07:00
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap Merge branch 'asoc-4.17' into asoc-4.18 for compress dependencies 2018-04-26 12:24:28 +01:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS
Kbuild
Kconfig kconfig: add basic helper macros to scripts/Kconfig.include 2018-05-29 03:31:19 +09:00
MAINTAINERS dmaengine fixes for v4.18-rc4 2018-07-07 17:29:08 -07:00
Makefile Linux 4.18-rc4 2018-07-08 16:34:02 -07:00
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.