kernel/linux.git/drivers/acpi/processor_idle.c, branch v6.19.11

Merge back ACPI processor driver changes for 6.19

2025-11-26T12:56:30+00:00

Revert "ACPI: processor: idle: Optimize ACPI idle driver registration"

2025-11-25T15:08:06+00:00

Revert commit 7a8c994cbb2d ("ACPI: processor: idle: Optimize ACPI idle driver registration") because it is reported to introduce a cpuidle regression leading to a kernel crash on a platform using the ACPI idle driver. Signed-off-by: Rafael J. Wysocki Reported-by: Borislav Petkov Tested-by: Borislav Petkov (AMD) Closes: https://lore.kernel.org/lkml/20251124200019.GIaSS5U9HhsWBotrQZ@fat_crate.local/

Revert "ACPI: processor: idle: Redefine two functions as void"

2025-11-25T13:53:33+00:00

Revert commit fbd401e95e56 ("ACPI: processor: idle: Redefine two functions as void") because it depends on a problematic one. Signed-off-by: Rafael J. Wysocki

Revert "ACPI: processor: Do not expose global variable acpi_idle_driver"

2025-11-25T13:50:25+00:00

Revert commit 559f2eacc8a2 ACPI: processor: Do not expose global variable acpi_idle_driver" because it depends on a problematic one. Signed-off-by: Rafael J. Wysocki

ACPI: processor: idle: Drop redundant C-state count checks

2025-11-07T17:47:58+00:00

acpi_processor_setup_cstates() and acpi_processor_setup_cpuidle_cx() are called after successfully obtaining power information. Among other things, these setup functions check the C-state count against zero. However, that check is done by acpi_processor_get_power_info_cst() which will cause acpi_processor_get_power_info() to fail if it does no pass, so the checks in the two functions mentioned above are redundant. Drop those redundant checks. No intentional functional impact. Signed-off-by: Huisong Li [ rjw: Subject and changelog rewrite ] Link: https://patch.msgid.link/20251105093647.3557248-1-lihuisong@huawei.com Signed-off-by: Rafael J. Wysocki

ACPI: processor: idle: Relocate state flags initialization

2025-10-22T14:47:40+00:00

Since acpi_processor_setup_cstates() is a more logical place for setting idle state flags than acpi_processor_setup_cpuidle_cx(), move that code from the latter to the former. It also allows direct references to acpi_idle_driver in acpi_processor_setup_cpuidle_cx() to be avoided. No intentional functional impact. Signed-off-by: Huisong Li [ rjw: Subject and changelog rewrite ] Link: https://patch.msgid.link/20250929093754.3998136-5-lihuisong@huawei.com Signed-off-by: Rafael J. Wysocki

ACPI: processor: Do not expose global variable acpi_idle_driver

2025-09-23T13:33:19+00:00

Move the cpuidle driver check from __acpi_processor_start() to acpi_processor_power_init() which allows variable acpi_idle_driver to become static. No intentional functional impact. Signed-off-by: Huisong Li Link: https://patch.msgid.link/20250923032428.2656329-2-lihuisong@huawei.com [ rjw: Subject tweak, new changelog, adjustment of a new comment ] Signed-off-by: Rafael J. Wysocki

ACPI: processor: idle: Redefine two functions as void

2025-09-19T20:49:49+00:00

Notice that acpi_processor_power_init() and acpi_processor_power_exit() don't need to return any values because their callers don't check them anyway, so redefine those functions as void. While at it, rearrange the code in acpi_processor_power_init() to reduce the indentation level, get rid of a redundant local variable in that function, and rephrase a code comment in it. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Mario Limonciello (AMD)

ACPI: processor: idle: Eliminate static variable flat_state_cnt

2025-09-02T14:08:53+00:00

Instead of using static variable flat_state_cnt to pass data between functions involved in the _LPI information processing, pass the current number of "flattened" idle states to flatten_lpi_states() and make it return the updated number of those states. At the same time, use a local variable called state_count to store the number of "flattened" idle states found so far in acpi_processor_get_lpi_info(). No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Sudeep Holla Tested-by: Sudeep Holla Acked-by: lihuisong@huawei.com Link: https://patch.msgid.link/10715991.nUPlyArG6x@rafael.j.wysocki

ACPI: processor: idle: Add module import namespace

2025-09-02T14:08:53+00:00

Add a new module import namespace called ACPI_PROCESSOR_IDLE for functions exported from the non-modular part of the ACPI processor driver to the modular part of it. Export acpi_processor_claim_cst_control() and acpi_processor_evaluate_cst() in that namespace to hide them from unrelated modules. They are also used by the intel_idle driver, but it is non-modular, so it can call them regardless of the way the symbols are exported. Signed-off-by: Rafael J. Wysocki Link: https://patch.msgid.link/3376499.aeNJFYEL58@rafael.j.wysocki