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Patrick Bellasi fa167475e1 UPSTREAM: sched/uclamp: Set default clamps for RT tasks
By default FAIR tasks start without clamps, i.e. neither boosted nor
capped, and they run at the best frequency matching their utilization
demand.  This default behavior does not fit RT tasks which instead are
expected to run at the maximum available frequency, if not otherwise
required by explicitly capping them.

Enforce the correct behavior for RT tasks by setting util_min to max
whenever:

 1. the task is switched to the RT class and it does not already have a
    user-defined clamp value assigned.

 2. an RT task is forked from a parent with RESET_ON_FORK set.

NOTE: utilization clamp values are cross scheduling class attributes and
thus they are never changed/reset once a value has been explicitly
defined from user-space.

Bug: 120440300
Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alessio Balsini <balsini@android.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Perret <quentin.perret@arm.com>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Steve Muckle <smuckle@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Todd Kjos <tkjos@google.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://lkml.kernel.org/r/20190621084217.8167-9-patrick.bellasi@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
(cherry picked from commit 1a00d99997)
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Change-Id: I81fcadaea34f557e531fa5ac6aab84fcb0ee37c7
Signed-off-by: Quentin Perret <qperret@google.com>
2020-02-01 14:39:38 +00:00
arch ANDROID: gki: Removed cf modules from gki_defconfig 2020-01-31 16:23:38 -08:00
block ANDROID: modularize BLK_MQ_VIRTIO 2020-01-31 16:11:59 -08:00
certs export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR() 2018-08-22 23:21:44 +09:00
crypto This is the 4.19.99 stable release 2020-01-27 15:55:44 +01:00
Documentation UPSTREAM: cgroup: add cgroup_parse_float() 2020-02-01 14:39:37 +00:00
drivers ANDROID: Remove default y for VIRTIO_PCI_LEGACY 2020-01-31 16:12:00 -08:00
firmware Fix built-in early-load Intel microcode alignment 2020-01-23 08:21:29 +01:00
fs ANDROID: Incremental fs: Remove unneeded compatibility typedef 2020-01-30 13:53:08 -08:00
include UPSTREAM: sched/uclamp: Extend sched_setattr() to support utilization clamping 2020-02-01 14:39:37 +00:00
init UPSTREAM: sched/uclamp: Add CPU's clamp buckets refcounting 2020-02-01 14:39:37 +00:00
ipc This is the 4.19.65 stable release 2019-08-06 20:08:18 +02:00
kernel UPSTREAM: sched/uclamp: Set default clamps for RT tasks 2020-02-01 14:39:38 +00:00
lib This is the 4.19.99 stable release 2020-01-27 15:55:44 +01:00
LICENSES LICENSES: Remove CC-BY-SA-4.0 license text 2018-10-18 11:28:50 +02:00
mm This is the 4.19.100 stable release 2020-01-29 17:10:45 +01:00
net This is the 4.19.100 stable release 2020-01-29 17:10:45 +01:00
samples samples/bpf: Fix broken xdp_rxq_info due to map order assumptions 2020-01-27 14:51:22 +01:00
scripts This is the 4.19.100 stable release 2020-01-29 17:10:45 +01:00
security This is the 4.19.99 stable release 2020-01-27 15:55:44 +01:00
sound This is the 4.19.99 stable release 2020-01-27 15:55:44 +01:00
tools ANDROID: Make incfs selftests pass 2020-01-30 11:25:57 -08:00
usr kbuild: clean compressed initramfs image 2019-10-07 18:57:16 +02:00
virt KVM: arm/arm64: vgic: Don't rely on the wrong pending table 2019-12-13 08:52:45 +01:00
.clang-format clang-format: Set IndentWrappedFunctionNames false 2018-08-01 18:38:51 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap libnvdimm-for-4.19_misc 2018-08-25 18:13:10 -07:00
abi_gki_aarch64_whitelist ANDROID: update ABI following inline crypto changes 2020-01-24 12:06:49 -08:00
abi_gki_aarch64.xml ANDROID: gki: Removed cf modules from gki_defconfig 2020-01-31 16:23:38 -08:00
build.config.aarch64 ANDROID: refactor build.config files to remove duplication 2019-10-22 18:27:12 -07:00
build.config.allmodconfig ANDROID: Don't base allmodconfig on gki_defconfig 2019-12-05 12:48:26 +00:00
build.config.allmodconfig.aarch64 ANDROID: Add allmodconfig build.configs for x86_64 and aarch64 2019-11-12 20:55:23 +00:00
build.config.allmodconfig.x86_64 ANDROID: Add allmodconfig build.configs for x86_64 and aarch64 2019-11-12 20:55:23 +00:00
build.config.common ANDROID: clang: update to 10.0.1 2019-11-27 12:37:18 -08:00
build.config.cuttlefish.aarch64 ANDROID: gki: Removed cf modules from gki_defconfig 2020-01-31 16:23:38 -08:00
build.config.cuttlefish.x86_64 ANDROID: gki: Removed cf modules from gki_defconfig 2020-01-31 16:23:38 -08:00
build.config.gki ANDROID: gki: Removed cf modules from gki_defconfig 2020-01-31 16:23:38 -08:00
build.config.gki.aarch64 ANDROID: add initial ABI whitelist for android-4.19 2019-12-18 12:44:33 +00:00
build.config.gki.x86_64 ANDROID: refactor build.config files to remove duplication 2019-10-22 18:27:12 -07:00
build.config.x86_64 ANDROID: refactor build.config files to remove duplication 2019-10-22 18:27:12 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
cuttlefish.fragment ANDROID: gki: Removed cf modules from gki_defconfig 2020-01-31 16:23:38 -08:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS This is the 4.19.80 stable release 2019-10-17 15:33:07 -07:00
Makefile This is the 4.19.100 stable release 2020-01-29 17:10:45 +01:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

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.