Minimal supplement to upstream Kernel Self Protection Project changes. Features already provided by SELinux + Yama and archs other than multiarch arm64 / x86_64 aren't in scope. Only tags have stable history. Shared IRC channel with KSPP: irc.libera.chat #linux-hardening
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Chris Wilson 74d290f845 drm/i915: Boost GPU clocks if we miss the pageflip's vblank
If we miss the current vblank because the gpu was busy, that may cause a
jitter as the frame rate temporarily drops. We try to limit the impact
of this by then boosting the GPU clock to deliver the frame as quickly
as possible. Originally done in commit 6ad790c0f5 ("drm/i915: Boost GPU
frequency if we detect outstanding pageflips") but was never forward
ported to atomic and finally dropped in commit fd3a40242e ("drm/i915:
Rip out legacy page_flip completion/irq handling").

One of the most typical use-cases for this is a mostly idle desktop.
Rendering one frame of the desktop's frontbuffer can easily be
accomplished by the GPU running at low frequency, but often exceeds
the time budget of the desktop compositor. The result is that animations
such as opening the menu, doing a fullscreen switch, or even just trying
to move a window around are slow and jerky. We need to respond within a
frame to give the best impression of a smooth UX, as a compromise we
instead respond if that first frame misses its goal. The result should
be a near-imperceivable initial delay and a smooth animation even
starting from idle. The cost, as ever, is that we spend more power than
is strictly necessary as we overestimate the required GPU frequency and
then try to ramp down.

This of course is reactionary, too little, too late; nevertheless it is
surprisingly effective.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102199
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170817123706.6777-1-chris@chris-wilson.co.uk
Tested-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Radoslaw Szwichtenberg <radoslaw.szwichtenberg@intel.com>
2017-08-22 17:08:06 +01:00
arch Linux 4.13-rc2 2017-07-27 08:15:43 +10:00
block bfq: dispatch request to prevent queue stalling after the request completion 2017-07-12 08:32:04 -06:00
certs modsign: add markers to endif-statements in certs/Makefile 2017-07-14 11:01:37 +10:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2017-07-14 22:49:50 -07:00
Documentation drm/i915: add register macro definition style guide 2017-08-10 22:47:32 +03:00
drivers drm/i915: Boost GPU clocks if we miss the pageflip's vblank 2017-08-22 17:08:06 +01:00
firmware firmware/Makefile: force recompilation if makefile changes 2017-05-08 17:15:10 -07:00
fs NFS client bugfixes for 4.13 2017-07-21 16:26:01 -07:00
include drm/i915: Add support for drm syncobjs 2017-08-15 16:46:57 +01:00
init random: do not ignore early device randomness 2017-07-12 16:26:00 -07:00
ipc ipc/util.h: update documentation for ipc_getref() and ipc_putref() 2017-07-12 16:26:02 -07:00
kernel Three minor updates 2017-07-21 13:59:51 -07:00
lib drm/i915: Replace execbuf vma ht with an idr 2017-08-18 11:59:02 +01:00
mm Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-07-15 12:00:42 -07:00
net NFS client bugfixes for 4.13 2017-07-21 16:26:01 -07:00
samples Merge branch 'akpm' (patches from Andrew) 2017-07-13 12:38:49 -07:00
scripts Properly alphabetize MAINTAINERS file 2017-07-23 16:06:21 -07:00
security Now that IPC and other changes have landed, enable manual markings for 2017-07-19 08:55:18 -07:00
sound sound fixes for 4.13-rc1 2017-07-14 12:44:00 -07:00
tools Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-21 11:12:48 -07:00
usr ramfs: clarify help text that compression applies to ramfs as well as legacy ramdisk. 2017-07-06 16:24:30 -07:00
virt Second batch of KVM updates for v4.13 2017-07-15 10:18:16 -07:00
.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: Add support to generate LLVM assembly files 2017-04-25 08:13:52 +09:00
.mailmap power supply and reset changes for the v4.12 series (part 2) 2017-05-12 12:02:21 -07:00
COPYING
CREDITS avr32: remove support for AVR32 architecture 2017-05-01 09:27:15 +02:00
Kbuild kbuild: Consolidate header generation from ASM offset information 2017-04-13 05:43:37 +09:00
Kconfig
MAINTAINERS MAINTAINERS: drm/i915 has a new maintainer team 2017-08-18 10:17:09 +02:00
Makefile Linux 4.13-rc2 2017-07-23 16:15:17 -07:00
README README: add a new README file, pointing to the Documentation/ 2016-10-24 08:12:35 -02:00

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.