Commit Graph

32 Commits

Author SHA1 Message Date
Ashwin Chaugule
56cdc2a05c ACPI: Add weak routines for ACPI CPU Hotplug
Add weak functions for architectures which do not support
hot-adding and removing CPUs which aren't detected at
bootup. (e.g. via MADT).

This helps preserve the Kconfig dependency from:

commit cbfc1bae55 ("[ACPI] ACPI_HOTPLUG_CPU Kconfig dependency
update")

    prevent:

    HOTPLUG_CPU=y
    ACPI_PROCESSOR=y
    ACPI_HOTPLUG_CPU=n

Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-10-12 23:08:03 +02:00
Mathias Krause
8ce344c66e ACPI / processor: remove leftover __refdata annotations
The processor_handler structure does not reference any __init / __exit
code or data. Therefore the __refdata annotation is not needed. It used
to be prior to commit fe7bf106eb ("acpi: delete __cpuinit usage from
all acpi files") due to the __cpuinit annotation of acpi_processor_add().
But with that commit in place that requirement has gone.

The same is true for the acpi_cpu_notifier notifier block.
acpi_cpu_soft_notify() used to be marked __cpuinit but lost its
annotation in the above mentioned commit as well. Therefore the __refdata
annotation isn't needed there either.

Just drop the unneded __refdata annotations to be able to catch future
section mismatches.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-07-21 01:01:46 +02:00
Hanjun Guo
ddcc18f5bd ACPI / processor: Introduce invalid_phys_cpuid()
Introduce invalid_phys_cpuid() to identify cpu with invalid
physical ID, then used it as replacement of the direct comparisons
with PHYS_CPUID_INVALID.

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-13 23:28:16 +02:00
Hanjun Guo
8416c5bda1 ACPI / processor: remove phys_id in acpi_processor_get_info()
Use pr->phys_id to replace phys_id to simplify the code.

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-13 23:28:15 +02:00
Hanjun Guo
05eb3cd8b4 ACPI / processor: remove cpu_index in acpi_processor_get_info()
Just use pr->id instead of cpu_index to simplify the code.

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-13 23:28:15 +02:00
Hanjun Guo
25956b6612 ACPI / processor: Introduce invalid_logical_cpuid()
In ACPI processor drivers, we use direct comparisons of cpu logical
id with -1 which are error prone in case logical cpuid is accidentally
assinged an error code and prevents us from returning an error-encoding
cpuid directly in some cases.

So introduce invalid_logical_cpuid() to identify cpu with invalid
logical cpu num, then it will be used to replace the direct comparisons
with -1.

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-13 23:28:14 +02:00
Catalin Marinas
828aef376d ACPI / processor: Introduce phys_cpuid_t for CPU hardware ID
CPU hardware ID (phys_id) is defined as u32 in structure acpi_processor,
but phys_id is used as int in acpi processor driver, so it will lead to
some inconsistence for the drivers.

Furthermore, to cater for ACPI arch ports that implement 64 bits CPU
ids a generic CPU physical id type is required.

So introduce typedef u32 phys_cpuid_t in a common file, and introduce
a macro PHYS_CPUID_INVALID as (phys_cpuid_t)(-1) if it's not defined
by other archs, this will solve the inconsistence in acpi processor driver,
and will prepare for the ACPI on ARM64 for the 64 bit CPU hardware ID
in the following patch.

CC: Rafael J Wysocki <rjw@rjwysocki.net>
Suggested-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Grant Likely <grant.likely@linaro.org>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
[hj: reworked cpu physid map return codes]
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-26 15:12:51 +00:00
Hanjun Guo
d02dc27db0 ACPI / processor: Rename acpi_(un)map_lsapic() to acpi_(un)map_cpu()
acpi_map_lsapic() will allocate a logical CPU number and map it to
physical CPU id (such as APIC id) for the hot-added CPU, it will also
do some mapping for NUMA node id and etc, acpi_unmap_lsapic() will
do the reverse.

We can see that the name of the function is a little bit confusing and
arch (IA64) dependent so rename them as acpi_(un)map_cpu() to make arch
agnostic and explicit.

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-01-05 23:34:26 +01:00
Hanjun Guo
af8f3f514d ACPI / processor: Convert apic_id to phys_id to make it arch agnostic
apic_id in MADT table is the CPU hardware id which identify
it self in the system for x86 and ia64, OSPM will use it for
SMP init to map APIC ID to logical cpu number in the early
boot, when the DSDT/SSDT (ACPI namespace) is scanned later, the
ACPI processor driver is probed and the driver will use acpi_id
in DSDT to get the apic_id, then map to the logical cpu number
which is needed by the processor driver.

Before ACPI 5.0, only x86 and ia64 were supported in ACPI spec,
so apic_id is used both in arch code and ACPI core which is
pretty fine. Since ACPI 5.0, ARM is supported by ACPI and
APIC is not available on ARM, this will confuse people when
apic_id is both used by x86 and ARM in one function.

So convert apic_id to phys_id (which is the original meaning)
in ACPI processor dirver to make it arch agnostic, but leave the
arch dependent code unchanged, no functional change.

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-01-05 23:32:42 +01:00
Graeme Gregory
b50154d53e ACPI: Don't use acpi_lapic in ACPI core code
Now ARM64 support is being added to ACPI so architecture specific
values can not be used in core ACPI code.

Following on the patch "ACPI / processor: Check if LAPIC is present
during initialization" which uses acpi_lapic in acpi_processor.c,
on ARM64 platform, GIC is used instead of local APIC, so acpi_lapic
is not a suitable value for ARM64.

What is actually important at this point is if there is/are CPU
entry/entries (Local APIC/SAPIC, GICC) in MADT, so introduce
acpi_has_cpu_in_madt() to be arch specific and generic.

Signed-off-by: Graeme Gregory <graeme.gregory@linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-07-21 13:50:58 +02:00
Baoquan He
c401eb8ee3 ACPI / processor: Check if LAPIC is present during initialization
In acpi_processor_get_info(), ACPI processor info is initialized including
ID, namely CPU index. Currently, on a UP system running an SMP kerenl with
no LAPIC in the MADT, cpu0_initialized is checked to decide whether or not
the CPU has been initialized.

However, this check may not be sufficient for kdump kernels. Most of time
only 1 CPU is supported because of known problems in kdump kernels. So say
the multiple CPUs are present in the boot kernel and a crash happens on
one specific CPU, say CPU2. Then it jumps into the kdump kernel with
"nr_cpus=1" in the command line. In this situation, the kdump kernel
will reuse the ACPI resources from the crashed kernel directly. That
means all LAPIC instances are enabled in the MADT while only one CPU is
in use.  In the kdump kernel, x86_cpu_to_apicid contains the correct APIC
ID and it's related to the CPU ID. If cpu0_initialized is checked only, 0
will be used as the CPU index instead of that APIC ID, which is not
correct.

In addition to checking cpu0_initialized, check acpi_lapic. If acpi_lapic
is 0, then no LAPIC is available from the MADT and the system should be
treated as a UP one without a LAPIC (that is, assign 0 to the CPU index).
Otherwise, use the original (valid) CPU index.

Signed-off-by: Baoquan He <bhe@redhat.com>
[rjw: Subject and changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-16 16:27:35 +02:00
Igor Mammedov
0b9d46dd7d ACPI / processor: do not mark present at boot but not onlined CPU as onlined
acpi_processor_add() assumes that present at boot CPUs
are always onlined, it is not so if a CPU failed to become
onlined. As result acpi_processor_add() will mark such CPU
device as onlined in sysfs and following attempts to
online/offline it using /sys/device/system/cpu/cpuX/online
attribute will fail.

Do not poke into device internals in acpi_processor_add()
and touch "struct device { .offline }" attribute, since
for CPUs onlined at boot it's set by:
  topology_init() -> arch_register_cpu() -> register_cpu()
before ACPI device tree is parsed, and for hotplugged
CPUs it's set when userspace onlines CPU via sysfs.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Cc: 3.11+ <stable@vger.kernel.org> # 3.11+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-08 12:59:36 +02:00
Lan Tianyu
4985c32ee4 ACPI / processor: Fix failure of loading acpi-cpufreq driver
According commit d640113fe (ACPI: processor: fix acpi_get_cpuid for UP
processor),  BIOS may not provide _MAT or MADT tables and acpi_get_apicid()
always returns -1. For these cases, original code will pass apic_id with
vaule of -1 to acpi_map_cpuid() and it will check the acpi_id. If acpi_id
is equal to zero, ignores apic_id and return zero for CPU0.

Commit b981513 (ACPI / scan: bail out early if failed to parse APIC
ID for CPU) changed the behavior. Return ENODEV when find apic_id is
less than zero after calling acpi_get_apicid(). This causes acpi-cpufreq
driver fails to be loaded on some machines. This patch is to fix it.

Fixes: b981513f80 (ACPI / scan: bail out early if failed to parse APIC ID for CPU)
References: https://bugzilla.kernel.org/show_bug.cgi?id=73781
Cc: 3.14+ <stable@vger.kernel.org> # 3.14+
Reported-and-tested-by: KATO Hiroshi <katoh@mikage.ne.jp>
Reported-and-tested-by: Stuart Foster <smf.linux@ntlworld.com>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-01 01:46:43 +02:00
Rafael J. Wysocki
82e180598b Merge branches 'acpi-processor', 'acpi-hotplug', 'acpi-init', 'acpi-pm' and 'acpica'
* acpi-processor:
  ACPI / scan: reduce log level of "ACPI: \_PR_.CPU4: failed to get CPU APIC ID"
  ACPI / processor: Return specific error value when mapping lapic id

* acpi-hotplug:
  ACPI / scan: Clear match_driver flag in acpi_bus_trim()

* acpi-init:
  ACPI / init: Flag use of ACPI and ACPI idioms for power supplies to regulator API

* acpi-pm:
  ACPI / PM: Use ACPI_COMPANION() to get ACPI companions of devices

* acpica:
  ACPICA: Remove bool usage from ACPICA.
2014-01-29 11:47:18 +01:00
Jiang Liu
f778d1218f ACPI / scan: reduce log level of "ACPI: \_PR_.CPU4: failed to get CPU APIC ID"
Commit b981513f80 (ACPI / scan: bail out early if failed to parse
APIC ID for CPU) emits an error message if ACPI processor driver fails
to query APIC ID for the CPU.

Originally it's designed to catch BIOS bugs for CPU hot-addition. But
it accidently reveals another type of BIOS bug that:
 1) BIOS implements ACPI objects for all possible instead of present
    CPUs. (It's valid to do that per ACPI specification.)
 2) BIOS doesn't implement the _STA method for CPU objects. OSPM assumes
    that all CPU objects are present and functioning and attempts to
    use those CPU objects for CPU enumeration, which then triggers the
    error message. According to ACPI spec, BIOS should implement _STA
    for those absent CPUs at least.

Though it's a BIOS bug in essential, there are some BIOSes in the fields
which are implmented in this way. So reduce the log level from ERR to
DEBUG to accommodate these existing BIOSes.

Fixes: b981513f80 (ACPI / scan: bail out early if failed to parse APIC ID for CPU)
Reported-and-tested-by: Jörg Otte <jrg.otte@gmail.com>
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-01-27 23:05:44 +01:00
Rafael J. Wysocki
bcc7201a91 Merge branches 'acpi-gpe', 'acpi-video', 'acpi-thermal', 'acpi-processor', 'acpi-sleep'
* acpi-gpe:
  ACPI / EC: disable GPE before removing GPE handler
  ACPI / Button: Fix enabling button GPEs twice

* acpi-video:
  ACPI: Blacklist Win8 OSI for some HP laptop 2013 models
  ACPI / video: Fix typo in video_detect.c

* acpi-thermal:
  ACPI / thermal: remove const from thermal_zone_device_ops declaration

* acpi-processor:
  ACPI / scan: bail out early if failed to parse APIC ID for CPU

* acpi-sleep:
  ACPI / sleep: remove panic in case hardware has changed after S4
2014-01-12 23:46:55 +01:00
Jiang Liu
b981513f80 ACPI / scan: bail out early if failed to parse APIC ID for CPU
Enhance ACPI CPU hotplug driver to print clear error message and
bail out early if BIOS returns wrong value in ACPI MADT table or
_MAT method. Otherwise it will add the CPU device even if failed
to get APIC ID and fails any operations against sysfs interface:
/sys/devices/system/cpu/cpux/online

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-01-11 01:31:38 +01:00
Rafael J. Wysocki
24dee1fc99 ACPI / bind: Pass struct acpi_device pointer to acpi_bind_one()
There is no reason to pass an ACPI handle to acpi_bind_one() instead
of a struct acpi_device pointer to the target device object, so
modify that function to take a struct acpi_device pointer as its
second argument and update all code depending on it accordingly.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Lan Tianyu <tianyu.lan@intel.com> # for USB/ACPI
2013-12-07 01:05:50 +01:00
Rafael J. Wysocki
3fbc4d6374 Merge branch 'acpi-processor'
* acpi-processor:
  ACPI / processor: fixed a brace coding style issue
  ACPI / processor: Remove outdated comments
  ACPI / processor: remove unnecessary if (!pr) check
  ACPI / processor: remove some dead code in acpi_processor_get_info()
  x86 / ACPI: simplify _acpi_map_lsapic()
  ACPI / processor: use apic_id and remove duplicated _MAT evaluation
  ACPI / processor: Introduce apic_id in struct processor to save parsed APIC id
2013-10-28 01:11:24 +01:00
Hanjun Guo
7cc34680c1 ACPI / processor: Remove outdated comments
acpi_get_processor_id() can be find nowhere, and the acpi id
is synchronized to APIC id when acpi_get_cpuid() is called, so
the comments can be removed.

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-24 01:39:40 +02:00
Hanjun Guo
082e12a05c ACPI / processor: remove unnecessary if (!pr) check
acpi_processor_errata() is only called in acpi_processor_get_info(),
and the argument 'pr' passed to acpi_processor_errata() will never be
NULL, so the if (!pr) check is unnecessary and can be removed.

Since the 'pr' argument is not used by acpi_processor_errata() any more,
so change the argument into void too.

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-24 01:39:40 +02:00
Jiang Liu
2d4d3e2a06 ACPI / processor: remove some dead code in acpi_processor_get_info()
errata.smp is used by nowhere, so the variable assignment is meanless,
remove it.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-24 01:39:40 +02:00
Jiang Liu
d536bf3dc9 ACPI / processor: use apic_id and remove duplicated _MAT evaluation
Since APIC id is saved in processor struct, just use it and
remove the duplicated _MAT evaluation.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-24 01:39:39 +02:00
Jiang Liu
ca9f62ac78 ACPI / processor: Introduce apic_id in struct processor to save parsed APIC id
For cpu hot add, we evaluate _MAT or parse MADT twice to get APIC id,
here is the code logic:
acpi_processor_add()
	acpi_processor_get_info()
		acpi_get_cpuid() will evaluate _MAT or parse MADT;
	acpi_processor_hotadd_init()
		acpi_map_lsapic() will evaluate _MAT again;

This can be done more effectively, this patch introduces apic_id in struct
processor to save parsed APIC id, and then we can use it and remove the
duplicated _MAT evaluation.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-24 01:39:39 +02:00
Zhang Rui
6ebb5bc9e6 acpi_processor: convert acpi_evaluate_object() to acpi_evaluate_integer()
acpi_evaluate_integer() is an ACPI API introduced to evaluate an
ACPI control method that is known to have an integer return value.
This API can simplify the code because the calling function does not need to
use the specified acpi_buffer structure required by acpi_evaluate_object();

Convert acpi_evaluate_object() to acpi_evaluate_integer()
in drivers/acpi/acpi_processor.c in this patch.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-24 01:37:56 +02:00
Toshi Kani
b9d10be7a8 ACPI / processor: Acquire writer lock to update CPU maps
CPU system maps are protected with reader/writer locks.  The reader
lock, get_online_cpus(), assures that the maps are not updated while
holding the lock.  The writer lock, cpu_hotplug_begin(), is used to
udpate the cpu maps along with cpu_maps_update_begin().

However, the ACPI processor handler updates the cpu maps without
holding the the writer lock.

acpi_map_lsapic() is called from acpi_processor_hotadd_init() to
update cpu_possible_mask and cpu_present_mask.  acpi_unmap_lsapic()
is called from acpi_processor_remove() to update cpu_possible_mask.
Currently, they are either unprotected or protected with the reader
lock, which is not correct.

For example, the get_online_cpus() below is supposed to assure that
cpu_possible_mask is not changed while the code is iterating with
for_each_possible_cpu().

        get_online_cpus();
        for_each_possible_cpu(cpu) {
		:
        }
        put_online_cpus();

However, this lock has no protection with CPU hotplug since the ACPI
processor handler does not use the writer lock when it updates
cpu_possible_mask.  The reader lock does not serialize within the
readers.

This patch protects them with the writer lock with cpu_hotplug_begin()
along with cpu_maps_update_begin(), which must be held before calling
cpu_hotplug_begin().  It also protects arch_register_cpu() /
arch_unregister_cpu(), which creates / deletes a sysfs cpu device
interface.  For this purpose it changes cpu_hotplug_begin() and
cpu_hotplug_done() to global and exports them in cpu.h.

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-13 12:20:16 +02:00
Yasuaki Ishimatsu
1e385f6f97 ACPI / processor: move try_offline_node() after acpi_unmap_lsapic()
try_offline_node() checks that all CPUs associated with the given
node have been removed by using cpu_present_bits.  If all cpus
related to that node have been removed, try_offline_node() clears
the node information.

However, try_offline_node() called from acpi_processor_remove() never
clears the node information.  For disabling cpu_present_bits,
acpi_unmap_lsapic() needs be called.  Yet, acpi_unmap_lsapic() is
called after try_offline_node() has run.  So when try_offline_node()
runs, the CPU's cpu_present_bits is always set.

Fix the issue by moving try_offline_node() after acpi_unmap_lsapic().

The problem fixed here was uncovered by commit cecdb19 "ACPI / scan:
Change the implementation of acpi_bus_trim()".

[rjw: Changelog]
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Cc: 3.9+ <stable@vger.kernel.org> # 3.9+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07 22:18:53 +02:00
Paul Gortmaker
fe7bf106eb acpi: delete __cpuinit usage from all acpi files
The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

This removes all the drivers/acpi uses of the __cpuinit macros
from all C files.

[1] https://lkml.org/lkml/2013/5/20/589

Cc: Len Brown <lenb@kernel.org>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: linux-acpi@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-07-14 19:36:58 -04:00
Hanjun Guo
173a5a4c90 ACPI / processor: Fix potential NULL pointer dereference in acpi_processor_add()
In acpi_processor_add(), get_cpu_device() may return NULL in some cases
which is then passed to acpi_bind_one() and that will case a NULL
pointer dereference to occur.

Add a check to prevent that from happening.

[rjw: Changelog]
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-06-01 22:23:39 +02:00
Rafael J. Wysocki
be547436c2 ACPI / processor: Pass processor object handle to acpi_bind_one()
Make acpi_processor_add() pass the ACPI handle of the processor
namespace object to acpi_bind_one() instead of setting it directly
to allow acpi_bind_one() to catch possible bugs causing the ACPI
handle of the processor device to be set earlier.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
2013-06-01 21:37:10 +02:00
Rafael J. Wysocki
2e4f1db49d ACPI / processor: Initialize per_cpu(processors, pr->id) properly
Commit ac212b6 (ACPI / processor: Use common hotplug infrastructure)
forgot about initializing the per-CPU 'processors' variables which
lead to ACPI cpuidle failure to use C-states and caused boot slowdown
on multi-CPU machines.

Fix the problem by adding per_cpu(processors, pr->id) initialization
to acpi_processor_add() and add make acpi_processor_remove() clean it
up as appropriate.

Also modify acpi_processor_stop() so that it doesn't clear
per_cpu(processors, pr->id) on processor driver removal which would
then cause problems to happen when the driver is loaded again.

This version of the patch contains fixes from Yinghai Lu.

Reported-and-tested-by: Yinghai Lu <yinghai@kernel.org>
Reported-and-tested-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-05-30 21:55:46 +02:00
Rafael J. Wysocki
ac212b6980 ACPI / processor: Use common hotplug infrastructure
Split the ACPI processor driver into two parts, one that is
non-modular, resides in the ACPI core and handles the enumeration
and hotplug of processors and one that implements the rest of the
existing processor driver functionality.

The non-modular part uses an ACPI scan handler object to enumerate
processors on the basis of information provided by the ACPI namespace
and to hook up with the common ACPI hotplug infrastructure.  It also
populates the ACPI handle of each processor device having a
corresponding object in the ACPI namespace, which allows the driver
proper to bind to those devices, and makes the driver bind to them
if it is readily available (i.e. loaded) when the scan handler's
.attach() routine is running.

There are a few reasons to make this change.

First, switching the ACPI processor driver to using the common ACPI
hotplug infrastructure reduces code duplication and size considerably,
even though a new file is created along with a header comment etc.

Second, since the common hotplug code attempts to offline devices
before starting the (non-reversible) removal procedure, it will abort
(and possibly roll back) hot-remove operations involving processors
if cpu_down() returns an error code for one of them instead of
continuing them blindly (if /sys/firmware/acpi/hotplug/force_remove
is unset).  That is a more desirable behavior than what the current
code does.

Finally, the separation of the scan/hotplug part from the driver
proper makes it possible to simplify the driver's .remove() routine,
because it doesn't need to worry about the possible cleanup related
to processor removal any more (the scan/hotplug part is responsible
for that now) and can handle device removal and driver removal
symmetricaly (i.e. as appropriate).

Some user-visible changes in sysfs are made (for example, the
'sysdev' link from the ACPI device node to the processor device's
directory is gone and a 'physical_node' link is present instead
and a corresponding 'firmware_node' is present in the processor
device's directory, the processor driver is now visible under
/sys/bus/cpu/drivers/ and bound to the processor device), but
that shouldn't affect the functionality that users care about
(frequency scaling, C-states and thermal management).

Tested on my venerable Toshiba Portege R500.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Toshi Kani <toshi.kani@hp.com>
2013-05-12 14:14:32 +02:00