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K Prateek Nayak d87e4026d1 cpufreq/amd-pstate: Enable ITMT support after initializing core rankings
When working on dynamic ITMT priority support, it was observed that
"asym_prefer_cpu" on AMD systems supporting Preferred Core ranking
was always set to the first CPU in the sched group when the system boots
up despite another CPU in the group having a higher ITMT ranking.

"asym_prefer_cpu" is cached when the sched domain hierarchy is
constructed. On AMD systems that support Preferred Core rankings, sched
domains are rebuilt when ITMT support is enabled for the first time from
amd_pstate*_cpu_init().

Since amd_pstate*_cpu_init() is called to initialize the cpudata for
each CPU, the ITMT support is enabled after the first CPU initializes
its asym priority but this is too early since other CPUs have not yet
initialized their asym priorities and the sched domain is rebuilt only
once when the support is toggled on for the first time.

Initialize the asym priorities first in amd_pstate*_cpu_init() and then
enable ITMT support later in amd_pstate_register_driver() to ensure all
CPUs have correctly initialized their asym priorities before sched
domain hierarchy is rebuilt.

Clear the ITMT support when the amd-pstate driver unregisters since core
rankings cannot be trusted unless the update_limits() callback is
operational.

Remove the delayed work mechanism now that ITMT support is only toggled
from the driver init path which is outside the cpuhp critical section.

Fixes: f3a0523918 ("cpufreq: amd-pstate: Enable amd-pstate preferred core support")
Signed-off-by: K Prateek Nayak <kprateek.nayak@amd.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Link: https://lore.kernel.org/r/20250411081439.27652-1-kprateek.nayak@amd.com
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
2025-04-11 12:49:57 -05:00
arch A set of final cleanups for the timer subsystem: 2025-04-06 08:35:37 -07:00
block treewide: Switch/rename to timer_delete[_sync]() 2025-04-05 10:30:12 +02:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto This push fixes reverts the multibuffer hash testing as it is buggy. 2025-04-02 09:14:59 -07:00
Documentation A set of final cleanups for the timer subsystem: 2025-04-06 08:35:37 -07:00
drivers cpufreq/amd-pstate: Enable ITMT support after initializing core rankings 2025-04-11 12:49:57 -05:00
fs Miscellaneous scheduler fixes/updates: 2025-04-06 10:44:58 -07:00
include A set of final cleanups for the timer subsystem: 2025-04-06 08:35:37 -07:00
init Miscellaneous scheduler fixes/updates: 2025-04-06 10:44:58 -07:00
io_uring io_uring: always do atomic put from iowq 2025-04-03 08:31:57 -06:00
ipc treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
kernel Fix a perf events time accounting bug. 2025-04-06 10:48:12 -07:00
lib Kbuild updates for v6.15 2025-04-05 15:46:50 -07:00
LICENSES LICENSES: add 0BSD license text 2024-09-01 20:43:24 -07:00
mm Disable SLUB_TINY for build testing 2025-04-06 10:00:04 -07:00
net treewide: Switch/rename to timer_delete[_sync]() 2025-04-05 10:30:12 +02:00
rust Kbuild updates for v6.15 2025-04-05 15:46:50 -07:00
samples treewide: Switch/rename to timer_delete[_sync]() 2025-04-05 10:30:12 +02:00
scripts Disable SLUB_TINY for build testing 2025-04-06 10:00:04 -07:00
security mseal sysmap: kernel config and header change 2025-04-01 15:17:14 -07:00
sound soundwire fix for 6.15-rc1 2025-04-06 12:04:53 -07:00
tools tools/include: make uapi/linux/types.h usable from assembly 2025-04-06 12:55:31 -07:00
usr kbuild: hdrcheck: fix cross build with clang 2025-03-05 04:06:45 +09:00
virt ARM: 2025-03-25 14:22:07 -07:00
.clang-format clang-format: Update with v6.11-rc1's for_each macro list 2024-08-02 13:20:31 +02:00
.clippy.toml rust: give Clippy the minimum supported Rust version 2025-01-10 00:17:25 +01:00
.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
.gitignore kbuild: Create intermediate vmlinux build with relocations preserved 2025-03-17 00:29:50 +09:00
.mailmap mailmap: add an entry for Nicolas Schier 2025-04-01 15:20:45 -07:00
.rustfmt.toml
COPYING
CREDITS Including fixes from netfilter. 2025-04-04 09:15:35 -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 Kbuild updates for v6.15 2025-04-05 15:46:50 -07:00
Makefile Linux 6.15-rc1 2025-04-06 13:11:33 -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 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.