linux.git/include/acpi/processor.h, branch v6.12.80

ACPI: processor: Move arch_init_invariance_cppc() call later

2024-11-06T20:31:36+00:00

arch_init_invariance_cppc() is called at the end of
acpi_cppc_processor_probe() in order to configure frequency invariance
based upon the values from _CPC.

This however doesn't work on AMD CPPC shared memory designs that have
AMD preferred cores enabled because _CPC needs to be analyzed from all
cores to judge if preferred cores are enabled.

This issue manifests to users as a warning since commit 21fb59ab4b97
("ACPI: CPPC: Adjust debug messages in amd_set_max_freq_ratio() to warn"):
```
Could not retrieve highest performance (-19)
```

However the warning isn't the cause of this, it was actually
commit 279f838a61f9 ("x86/amd: Detect preferred cores in
amd_get_boost_ratio_numerator()") which exposed the issue.

To fix this problem, change arch_init_invariance_cppc() into a new weak
symbol that is called at the end of acpi_processor_driver_init().
Each architecture that supports it can declare the symbol to override
the weak one.

Define it for x86, in arch/x86/kernel/acpi/cppc.c, and for all of the
architectures using the generic arch_topology.c code.

Fixes: 279f838a61f9 ("x86/amd: Detect preferred cores in amd_get_boost_ratio_numerator()")
Reported-by: Ivan Shapovalov 
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219431
Tested-by: Oleksandr Natalenko 
Signed-off-by: Mario Limonciello 
Link: https://patch.msgid.link/20241104222855.3959267-1-superm1@kernel.org
[ rjw: Changelog edit ]
Signed-off-by: Rafael J. Wysocki

ACPI: processor: Simplify initial onlining to use same path for cold and hotplug

2024-06-28T17:38:27+00:00

Separate code paths, combined with a flag set in acpi_processor.c to
indicate a struct acpi_processor was for a hotplugged CPU ensured that
per CPU data was only set up the first time that a CPU was initialized.
This appears to be unnecessary as the paths can be combined by letting
the online logic also handle any CPUs online at the time of driver load.

Motivation for this change, beyond simplification, is that ARM64
virtual CPU HP uses the same code paths for hotplug and cold path in
acpi_processor.c so had no easy way to set the flag for hotplug only.
Removing this necessity will enable ARM64 vCPU HP to reuse the existing
code paths.

Acked-by: Rafael J. Wysocki 
Reviewed-by: Hanjun Guo 
Tested-by: Miguel Luis 
Reviewed-by: Gavin Shan 
Reviewed-by: Miguel Luis 
Signed-off-by: Jonathan Cameron 
Link: https://lore.kernel.org/r/20240529133446.28446-2-Jonathan.Cameron@huawei.com
Signed-off-by: Catalin Marinas

cpu-hotplug: Provide prototypes for arch CPU registration

2023-10-11T12:27:37+00:00

Provide common prototypes for arch_register_cpu() and
arch_unregister_cpu(). These are called by acpi_processor.c, with weak
versions, so the prototype for this is already set. It is generally not
necessary for function prototypes to be conditional on preprocessor macros.

Some architectures (e.g. Loongarch) are missing the prototype for this, and
rather than add it to Loongarch's asm/cpu.h, do the job once for everyone.

Since this covers everyone, remove the now unnecessary prototypes in
asm/cpu.h, and therefore remove the 'static' from one of ia64's
arch_register_cpu() definitions.

[ tglx: Bring back the ia64 part and remove the ACPI prototypes ]

Signed-off-by: Russell King (Oracle) 
Signed-off-by: Thomas Gleixner 
Link: https://lore.kernel.org/r/E1qkoRr-0088Q8-Da@rmk-PC.armlinux.org.uk

ACPI: processor: Silence missing prototype warnings

2022-11-23T18:36:46+00:00

Silence the following warnings when built with W=1:

 | CC   drivers/acpi/acpi_processor.c
 |      warning: no previous prototype for 'arch_register_cpu' [-Wmissing-prototypes]
 |              int __weak arch_register_cpu(int cpu)
 |                         ^
 | CC   drivers/acpi/acpi_processor.c
 |      warning: no previous prototype for 'arch_unregister_cpu' [-Wmissing-prototypes]
 |              void __weak arch_unregister_cpu(int cpu) {}
 |                          ^

Reported-by: kernel test robot 
Signed-off-by: Sudeep Holla 
Signed-off-by: Rafael J. Wysocki

ACPI: processor_idle: Silence missing prototype warnings

2022-11-23T18:36:40+00:00

Silence the following warnings when built with W=1:

 | CC   drivers/acpi/processor_idle.c
 |      warning: no previous prototype for 'acpi_processor_ffh_lpi_probe' [-Wmissing-prototypes]
 |		int __weak acpi_processor_ffh_lpi_probe(unsigned int cpu)
 |                         ^
 | CC   drivers/acpi/processor_idle.c
 |      warning: no previous prototype for 'acpi_processor_ffh_lpi_enter' [-Wmissing-prototypes]
 |              int __weak acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi)
 |                         ^

Reported-by: kernel test robot 
Signed-off-by: Sudeep Holla 
Signed-off-by: Rafael J. Wysocki

ACPI: processor: Drop leftover acpi_processor_get_limit_info() declaration

2022-06-29T17:01:23+00:00

Commit 22e7551eb6fd ("ACPI / processor: Remove acpi_processor_get_limit_info()"),
left it behind, so drop it.

Signed-off-by: Riwen Lu 
Reviewed-by: Punit Agrawal 
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki

ACPI: processor: Split out thermal initialization from ACPI PSS

2022-06-29T16:51:22+00:00

Commit 239708a3af44 ("ACPI: Split out ACPI PSS from ACPI Processor
driver"), moves processor thermal registration to acpi_pss_perf_init(),
which doesn't get executed if ACPI_CPU_FREQ_PSS is not enabled.

As ARM64 supports P-states using CPPC, it should be possible to also
support processor passive cooling even if PSS is not enabled. Split
out the processor thermal cooling register from ACPI PSS to support
this, and move it into a separate function in processor_thermal.c.

Signed-off-by: Riwen Lu 
Reviewed-by: Punit Agrawal 
[ rjw: Subject edits ]
Signed-off-by: Rafael J. Wysocki

ACPI: processor: Replace kernel.h with the necessary inclusions

2021-11-24T16:44:04+00:00

When kernel.h is used in the headers it adds a lot into dependency hell,
especially when there are circular dependencies are involved.

Replace kernel.h inclusion with the list of what is really being used.

Signed-off-by: Andy Shevchenko 
Signed-off-by: Rafael J. Wysocki

x86: ACPI: fix CPU hotplug deadlock

2020-04-04T14:28:24+00:00

Similar to commit 0266d81e9bf5 ("acpi/processor: Prevent cpu hotplug
deadlock") except this is for acpi_processor_ffh_cstate_probe():

"The problem is that the work is scheduled on the current CPU from the
hotplug thread associated with that CPU.

It's not required to invoke these functions via the workqueue because
the hotplug thread runs on the target CPU already.

Check whether current is a per cpu thread pinned on the target CPU and
invoke the function directly to avoid the workqueue."

 WARNING: possible circular locking dependency detected
 ------------------------------------------------------
 cpuhp/1/15 is trying to acquire lock:
 ffffc90003447a28 ((work_completion)(&wfc.work)){+.+.}-{0:0}, at: __flush_work+0x4c6/0x630

 but task is already holding lock:
 ffffffffafa1c0e8 (cpuidle_lock){+.+.}-{3:3}, at: cpuidle_pause_and_lock+0x17/0x20

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #1 (cpu_hotplug_lock){++++}-{0:0}:
 cpus_read_lock+0x3e/0xc0
 irq_calc_affinity_vectors+0x5f/0x91
 __pci_enable_msix_range+0x10f/0x9a0
 pci_alloc_irq_vectors_affinity+0x13e/0x1f0
 pci_alloc_irq_vectors_affinity at drivers/pci/msi.c:1208
 pqi_ctrl_init+0x72f/0x1618 [smartpqi]
 pqi_pci_probe.cold.63+0x882/0x892 [smartpqi]
 local_pci_probe+0x7a/0xc0
 work_for_cpu_fn+0x2e/0x50
 process_one_work+0x57e/0xb90
 worker_thread+0x363/0x5b0
 kthread+0x1f4/0x220
 ret_from_fork+0x27/0x50

 -> #0 ((work_completion)(&wfc.work)){+.+.}-{0:0}:
 __lock_acquire+0x2244/0x32a0
 lock_acquire+0x1a2/0x680
 __flush_work+0x4e6/0x630
 work_on_cpu+0x114/0x160
 acpi_processor_ffh_cstate_probe+0x129/0x250
 acpi_processor_evaluate_cst+0x4c8/0x580
 acpi_processor_get_power_info+0x86/0x740
 acpi_processor_hotplug+0xc3/0x140
 acpi_soft_cpu_online+0x102/0x1d0
 cpuhp_invoke_callback+0x197/0x1120
 cpuhp_thread_fun+0x252/0x2f0
 smpboot_thread_fn+0x255/0x440
 kthread+0x1f4/0x220
 ret_from_fork+0x27/0x50

 other info that might help us debug this:

 Chain exists of:
 (work_completion)(&wfc.work) --> cpuhp_state-up --> cpuidle_lock

 Possible unsafe locking scenario:

 CPU0                    CPU1
 ----                    ----
 lock(cpuidle_lock);
                         lock(cpuhp_state-up);
                         lock(cpuidle_lock);
 lock((work_completion)(&wfc.work));

 *** DEADLOCK ***

 3 locks held by cpuhp/1/15:
 #0: ffffffffaf51ab10 (cpu_hotplug_lock){++++}-{0:0}, at: cpuhp_thread_fun+0x69/0x2f0
 #1: ffffffffaf51ad40 (cpuhp_state-up){+.+.}-{0:0}, at: cpuhp_thread_fun+0x69/0x2f0
 #2: ffffffffafa1c0e8 (cpuidle_lock){+.+.}-{3:3}, at: cpuidle_pause_and_lock+0x17/0x20

 Call Trace:
 dump_stack+0xa0/0xea
 print_circular_bug.cold.52+0x147/0x14c
 check_noncircular+0x295/0x2d0
 __lock_acquire+0x2244/0x32a0
 lock_acquire+0x1a2/0x680
 __flush_work+0x4e6/0x630
 work_on_cpu+0x114/0x160
 acpi_processor_ffh_cstate_probe+0x129/0x250
 acpi_processor_evaluate_cst+0x4c8/0x580
 acpi_processor_get_power_info+0x86/0x740
 acpi_processor_hotplug+0xc3/0x140
 acpi_soft_cpu_online+0x102/0x1d0
 cpuhp_invoke_callback+0x197/0x1120
 cpuhp_thread_fun+0x252/0x2f0
 smpboot_thread_fn+0x255/0x440
 kthread+0x1f4/0x220
 ret_from_fork+0x27/0x50

Signed-off-by: Qian Cai 
Tested-by: Borislav Petkov 
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki

cpufreq: Use per-policy frequency QoS

2019-10-21T00:05:21+00:00

Replace the CPU device PM QoS used for the management of min and max
frequency constraints in cpufreq (and its users) with per-policy
frequency QoS to avoid problems with cpufreq policies covering
more then one CPU.

Namely, a cpufreq driver is registered with the subsys interface
which calls cpufreq_add_dev() for each CPU, starting from CPU0, so
currently the PM QoS notifiers are added to the first CPU in the
policy (i.e. CPU0 in the majority of cases).

In turn, when the cpufreq driver is unregistered, the subsys interface
doing that calls cpufreq_remove_dev() for each CPU, starting from CPU0,
and the PM QoS notifiers are only removed when cpufreq_remove_dev() is
called for the last CPU in the policy, say CPUx, which as a rule is
not CPU0 if the policy covers more than one CPU.  Then, the PM QoS
notifiers cannot be removed, because CPUx does not have them, and
they are still there in the device PM QoS notifiers list of CPU0,
which prevents new PM QoS notifiers from being registered for CPU0
on the next attempt to register the cpufreq driver.

The same issue occurs when the first CPU in the policy goes offline
before unregistering the driver.

After this change it does not matter which CPU is the policy CPU at
the driver registration time and whether or not it is online all the
time, because the frequency QoS is per policy and not per CPU.

Fixes: 67d874c3b2c6 ("cpufreq: Register notifiers with the PM QoS framework")
Reported-by: Dmitry Osipenko 
Tested-by: Dmitry Osipenko 
Reported-by: Sudeep Holla 
Tested-by: Sudeep Holla 
Diagnosed-by: Viresh Kumar 
Link: https://lore.kernel.org/linux-pm/5ad2624194baa2f53acc1f1e627eb7684c577a19.1562210705.git.viresh.kumar@linaro.org/T/#md2d89e95906b8c91c15f582146173dce2e86e99f
Link: https://lore.kernel.org/linux-pm/20191017094612.6tbkwoq4harsjcqv@vireshk-i7/T/#m30d48cc23b9a80467fbaa16e30f90b3828a5a29b
Signed-off-by: Rafael J. Wysocki 
Acked-by: Viresh Kumar