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Daniele Ceraolo Spurio 26caeae9fb
drm/xe/guc: Set RCS/CCS yield policy
All recent platforms (including all the ones officially supported by the
Xe driver) do not allow concurrent execution of RCS and CCS workloads
from different address spaces, with the HW blocking the context switch
when it detects such a scenario.
The DUAL_QUEUE flag helps with this, by causing the GuC to not submit a
context it knows will not be able to execute. This, however, causes a new
problem: if RCS and CCS queues have pending workloads from different
address spaces, the GuC needs to choose from which of the 2 queues to
pick the next workload to execute. By default, the GuC prioritizes RCS
submissions over CCS ones, which can lead to CCS workloads being
significantly (or completely) starved of execution time.
The driver can tune this by setting a dedicated scheduling policy KLV;
this KLV allows the driver to specify a quantum (in ms) and a ratio
(percentage value between 0 and 100), and the GuC will prioritize the CCS
for that percentage of each quantum.
Given that we want to guarantee enough RCS throughput to avoid missing
frames, we set the yield policy to 20% of each 80ms interval.

v2: updated quantum and ratio, improved comment, use xe_guc_submit_disable
in gt_sanitize

Fixes: d9a1ae0d17 ("drm/xe/guc: Enable WA_DUAL_QUEUE for newer platforms")
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Tested-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
Link: https://lore.kernel.org/r/20250905235632.3333247-2-daniele.ceraolospurio@intel.com
(cherry picked from commit 8843444843)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
[Rodrigo added #include "xe_guc_submit.h" while backporting]
2025-09-17 20:23:47 -04:00
arch Fix a CPU topology parsing bug on AMD guests, and address 2025-09-14 08:39:48 -07:00
block vfs-6.17-rc6.fixes 2025-09-08 07:53:01 -07:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto crypto: sha512 - Implement export_core() and import_core() 2025-09-02 19:02:39 -07:00
Documentation Generic phy driver fixes for 6.17 2025-09-14 13:17:30 -07:00
drivers drm/xe/guc: Set RCS/CCS yield policy 2025-09-17 20:23:47 -04:00
fs Fix a CPU topology parsing bug on AMD guests, and address 2025-09-14 08:39:48 -07:00
include Including fixes from CAN, netfilter and wireless. 2025-09-11 08:54:42 -07:00
init 20 hotfixes. 15 are cc:stable and the remainder address post-6.16 issues 2025-09-10 21:19:34 -07:00
io_uring vfs-6.17-rc6.fixes 2025-09-08 07:53:01 -07:00
ipc vfs-6.17-rc1.mmap_prepare 2025-07-28 13:43:25 -07:00
kernel Fix a lost-timeout CPU hotplug bug in the hrtimer code, which 2025-09-14 08:38:05 -07:00
lib hardening fixes for v6.17-rc4 2025-08-31 08:56:45 -07:00
LICENSES LICENSES: Replace the obsolete address of the FSF in the GFDL-1.2 2025-07-24 11:15:39 +02:00
mm 20 hotfixes. 15 are cc:stable and the remainder address post-6.16 issues 2025-09-10 21:19:34 -07:00
net A fix for a race condition around r_parent tracking that took a long 2025-09-13 10:45:11 -07:00
rust Driver core fixes for 6.17-rc6 2025-09-13 10:36:06 -07:00
samples ftrace/samples: Fix function size computation 2025-09-05 18:39:12 -04:00
scripts Rust fixes for v6.17 (2nd) 2025-09-06 12:33:09 -07:00
security + Features 2025-08-04 08:17:28 -07:00
sound ALSA: hda/hdmi: Add pin fix for another HP EliteDesk 800 G4 model 2025-09-01 13:51:57 +02:00
tools Including fixes from CAN, netfilter and wireless. 2025-09-11 08:54:42 -07:00
usr usr/include: openrisc: don't HDRTEST bpf_perf_event.h 2025-05-12 15:03:17 +09:00
virt Merge tag 'kvm-x86-no_assignment-6.17' of https://github.com/kvm-x86/linux into HEAD 2025-07-29 08:36:42 -04:00
.clang-format Linux 6.15-rc5 2025-05-06 16:39:25 +10:00
.clippy.toml rust: clean Rust 1.88.0's warning about clippy::disallowed_macros configuration 2025-05-07 00:11:47 +02:00
.cocciconfig
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: Retire Ralf Baechle 2024-11-12 15:48:59 +01:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore gitignore: allow .pylintrc to be tracked 2025-07-02 17:10:04 -06:00
.mailmap MAINTAINERS: Update Nobuhiro Iwamatsu's email address 2025-09-01 10:36:10 +02:00
.pylintrc docs: add a .pylintrc file with sys path for docs scripts 2025-04-09 12:10:33 -06:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING
CREDITS MAINTAINERS: retire Boris from TLS maintainers 2025-08-26 17:36:01 -07:00
Kbuild drm: ensure drm headers are self-contained and pass kernel-doc 2025-02-12 10:44:43 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS Input updates for v6.17-rc5 2025-09-14 08:09:37 -07:00
Makefile Linux 6.17-rc6 2025-09-14 14:21:14 -07:00
README README: Fix spelling 2024-03-18 03:36:32 -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 reStructuredText 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.