kernel/linux.git/drivers/acpi/processor_idle.c, branch v5.15.7

ACPI: processor: Replace deprecated CPU-hotplug functions

2021-08-04T18:25:54+00:00

The functions cpu_hotplug_begin, cpu_hotplug_done, get_online_cpus() and put_online_cpus() have been deprecated during the CPU hotplug rework. They map directly to cpus_write_lock(), cpus_write_unlock, cpus_read_lock() and cpus_read_unlock(). Replace deprecated CPU-hotplug functions with the official version. The behavior remains unchanged. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Rafael J. Wysocki

ACPI: processor idle: Fix up C-state latency if not ordered

2021-05-17T15:05:30+00:00

Generally, the C-state latency is provided by the _CST method or FADT, but some OEM platforms using AMD Picasso, Renoir, Van Gogh, and Cezanne set the C2 latency greater than C3's which causes the C2 state to be skipped. That will block the core entering PC6, which prevents S0ix working properly on Linux systems. In other operating systems, the latency values are not validated and this does not cause problems by skipping states. To avoid this issue on Linux, detect when latencies are not an arithmetic progression and sort them. Link: https://gitlab.freedesktop.org/agd5f/linux/-/commit/026d186e4592c1ee9c1cb44295912d0294508725 Link: https://gitlab.freedesktop.org/drm/amd/-/issues/1230#note_712174 Suggested-by: Prike Liang Suggested-by: Alex Deucher Signed-off-by: Mario Limonciello [ rjw: Subject and changelog edits ] Signed-off-by: Rafael J. Wysocki

Merge branches 'acpi-pci' and 'acpi-processor'

2021-04-26T15:03:05+00:00

* acpi-pci: ACPI: PCI: Replace direct printk() invocations in pci_link.c ACPI: PCI: Drop ACPI_PCI_COMPONENT that is not used any more ACPI: PCI: Replace ACPI_DEBUG_PRINT() and ACPI_EXCEPTION() ACPI: PCI: IRQ: Consolidate printing diagnostic messages * acpi-processor: ACPI: processor: perflib: Eliminate redundant status check ACPI: processor: Get rid of ACPICA message printing ACPI: processor: idle: Drop extra prefix from pr_notice() ACPI: processor: Remove initialization of static variable

ACPI: processor: Fix build when CONFIG_ACPI_PROCESSOR=m

2021-04-07T17:02:43+00:00

Commit 8cdddd182bd7 ("ACPI: processor: Fix CPU0 wakeup in acpi_idle_play_dead()") tried to fix CPU0 hotplug breakage by copying wakeup_cpu0() + start_cpu0() logic from hlt_play_dead()//mwait_play_dead() into acpi_idle_play_dead(). The problem is that these functions are not exported to modules so when CONFIG_ACPI_PROCESSOR=m build fails. The issue could've been fixed by exporting both wakeup_cpu0()/start_cpu0() (the later from assembly) but it seems putting the whole pattern into a new function and exporting it instead is better. Reported-by: kernel test robot Fixes: 8cdddd182bd7 ("CPI: processor: Fix CPU0 wakeup in acpi_idle_play_dead()") Cc: # 5.10+ Signed-off-by: Vitaly Kuznetsov Signed-off-by: Rafael J. Wysocki

Merge back 'acpi-processor' material for v5.13.

2021-04-06T13:00:13+00:00

ACPI: processor: Fix CPU0 wakeup in acpi_idle_play_dead()

2021-04-01T11:37:55+00:00

Commit 496121c02127 ("ACPI: processor: idle: Allow probing on platforms with one ACPI C-state") broke CPU0 hotplug on certain systems, e.g. I'm observing the following on AWS Nitro (e.g r5b.xlarge but other instance types are affected as well): # echo 0 > /sys/devices/system/cpu/cpu0/online # echo 1 > /sys/devices/system/cpu/cpu0/online <10 seconds delay> -bash: echo: write error: Input/output error In fact, the above mentioned commit only revealed the problem and did not introduce it. On x86, to wakeup CPU an NMI is being used and hlt_play_dead()/mwait_play_dead() loops are prepared to handle it: /* * If NMI wants to wake up CPU0, start CPU0. */ if (wakeup_cpu0()) start_cpu0(); cpuidle_play_dead() -> acpi_idle_play_dead() (which is now being called on systems where it wasn't called before the above mentioned commit) serves the same purpose but it doesn't have a path for CPU0. What happens now on wakeup is: - NMI is sent to CPU0 - wakeup_cpu0_nmi() works as expected - we get back to while (1) loop in acpi_idle_play_dead() - safe_halt() puts CPU0 to sleep again. The straightforward/minimal fix is add the special handling for CPU0 on x86 and that's what the patch is doing. Fixes: 496121c02127 ("ACPI: processor: idle: Allow probing on platforms with one ACPI C-state") Signed-off-by: Vitaly Kuznetsov Cc: 5.10+ # 5.10+ Signed-off-by: Rafael J. Wysocki

ACPI: processor: Get rid of ACPICA message printing

2021-03-08T15:51:19+00:00

The ACPI_DEBUG_PRINT() and ACPI_EXCEPTION() macros are used for message printing in the ACPICA code and they should not be used elsewhere. Special configuration (either kernel command line or sysfs-based) is needed to see the messages printed by them and the format of those messages is also special and convoluted. For this reason, replace all of the ACPI_DEBUG_PRINT() and ACPI_EXCEPTION() instances in the ACPI processor driver with corresponding dev_*(), acpi_handle_*() and pr_*() calls depending on the context in which they appear. Also drop the ACPI_PROCESSOR_COMPONENT definition that is not going to be necessary any more. Signed-off-by: Rafael J. Wysocki Reviewed-by: Hanjun Guo

ACPI: processor: idle: Drop extra prefix from pr_notice()

2021-03-08T15:51:19+00:00

Drop "ACPI: " from the pr_noitice() instance in acpi_processor_cstate_first_run_checks(), because pr_fmt() causes that prefix to be added to the message already. Reported-by: Hanjun Guo Signed-off-by: Rafael J. Wysocki Reviewed-by: Hanjun Guo

ACPI: processor: Remove the duplicated ACPI_PROCESSOR_CLASS macro

2020-11-17T17:12:34+00:00

The ACPI_PROCESSOR_CLASS macro is defined in , and ACPI drivers for processor already included , so we can remove those duplicated ACPI_PROCESSOR_CLASS macros. Signed-off-by: Hanjun Guo Signed-off-by: Rafael J. Wysocki

ACPI: processor: Fix build for ARCH_APICTIMER_STOPS_ON_C3 unset

2020-09-23T11:50:12+00:00

Fix the lapic_timer_needs_broadcast() stub for ARCH_APICTIMER_STOPS_ON_C3 unset to actually return a value. Fixes: aa6b43d57f99 ("ACPI: processor: Use CPUIDLE_FLAG_TIMER_STOP") Reported-by: Guenter Roeck Signed-off-by: Rafael J. Wysocki