<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux/drivers/base/cpu.c, branch v3.12.14</title>
<subtitle>Linux kernel source tree</subtitle>
<id>https://git.amat.us/linux/atom/drivers/base/cpu.c?h=v3.12.14</id>
<link rel='self' href='https://git.amat.us/linux/atom/drivers/base/cpu.c?h=v3.12.14'/>
<link rel='alternate' type='text/html' href='https://git.amat.us/linux/'/>
<updated>2013-09-03T22:59:39Z</updated>
<entry>
<title>Merge tag 'pm+acpi-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm</title>
<updated>2013-09-03T22:59:39Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2013-09-03T22:59:39Z</published>
<link rel='alternate' type='text/html' href='https://git.amat.us/linux/commit/?id=40031da445fb4d269af9c7c445b2adf674f171e7'/>
<id>urn:sha1:40031da445fb4d269af9c7c445b2adf674f171e7</id>
<content type='text'>
Pull ACPI and power management updates from Rafael Wysocki:

 1) ACPI-based PCI hotplug (ACPIPHP) subsystem rework and introduction
    of Intel Thunderbolt support on systems that use ACPI for signalling
    Thunderbolt hotplug events.  This also should make ACPIPHP work in
    some cases in which it was known to have problems.  From
    Rafael J Wysocki, Mika Westerberg and Kirill A Shutemov.

 2) ACPI core code cleanups and dock station support cleanups from
    Jiang Liu and Rafael J Wysocki.

 3) Fixes for locking problems related to ACPI device hotplug from
    Rafael J Wysocki.

 4) ACPICA update to version 20130725 includig fixes, cleanups, support
    for more than 256 GPEs per GPE block and a change to make the ACPI
    PM Timer optional (we've seen systems without the PM Timer in the
    field already).  One of the fixes, related to the DeRefOf operator,
    is necessary to prevent some Windows 8 oriented AML from causing
    problems to happen.  From Bob Moore, Lv Zheng, and Jung-uk Kim.

 5) Removal of the old and long deprecated /proc/acpi/event interface
    and related driver changes from Thomas Renninger.

 6) ACPI and Xen changes to make the reduced hardware sleep work with
    the latter from Ben Guthro.

 7) ACPI video driver cleanups and a blacklist of systems that should
    not tell the BIOS that they are compatible with Windows 8 (or ACPI
    backlight and possibly other things will not work on them).  From
    Felipe Contreras.

 8) Assorted ACPI fixes and cleanups from Aaron Lu, Hanjun Guo,
    Kuppuswamy Sathyanarayanan, Lan Tianyu, Sachin Kamat, Tang Chen,
    Toshi Kani, and Wei Yongjun.

 9) cpufreq ondemand governor target frequency selection change to
    reduce oscillations between min and max frequencies (essentially,
    it causes the governor to choose target frequencies proportional
    to load) from Stratos Karafotis.

10) cpufreq fixes allowing sysfs attributes file permissions to be
    preserved over suspend/resume cycles Srivatsa S Bhat.

11) Removal of Device Tree parsing for CPU device nodes from multiple
    cpufreq drivers that required some changes related to
    of_get_cpu_node() to be made in a few architectures and in the
    driver core.  From Sudeep KarkadaNagesha.

12) cpufreq core fixes and cleanups related to mutual exclusion and
    driver module references from Viresh Kumar, Lukasz Majewski and
    Rafael J Wysocki.

13) Assorted cpufreq fixes and cleanups from Amit Daniel Kachhap,
    Bartlomiej Zolnierkiewicz, Hanjun Guo, Jingoo Han, Joseph Lo,
    Julia Lawall, Li Zhong, Mark Brown, Sascha Hauer, Stephen Boyd,
    Stratos Karafotis, and Viresh Kumar.

14) Fixes to prevent race conditions in coupled cpuidle from happening
    from Colin Cross.

15) cpuidle core fixes and cleanups from Daniel Lezcano and
    Tuukka Tikkanen.

16) Assorted cpuidle fixes and cleanups from Daniel Lezcano,
    Geert Uytterhoeven, Jingoo Han, Julia Lawall, Linus Walleij,
    and Sahara.

17) System sleep tracing changes from Todd E Brandt and Shuah Khan.

18) PNP subsystem conversion to using struct dev_pm_ops for power
    management from Shuah Khan.

* tag 'pm+acpi-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (217 commits)
  cpufreq: Don't use smp_processor_id() in preemptible context
  cpuidle: coupled: fix race condition between pokes and safe state
  cpuidle: coupled: abort idle if pokes are pending
  cpuidle: coupled: disable interrupts after entering safe state
  ACPI / hotplug: Remove containers synchronously
  driver core / ACPI: Avoid device hot remove locking issues
  cpufreq: governor: Fix typos in comments
  cpufreq: governors: Remove duplicate check of target freq in supported range
  cpufreq: Fix timer/workqueue corruption due to double queueing
  ACPI / EC: Add ASUSTEK L4R to quirk list in order to validate ECDT
  ACPI / thermal: Add check of "_TZD" availability and evaluating result
  cpufreq: imx6q: Fix clock enable balance
  ACPI: blacklist win8 OSI for buggy laptops
  cpufreq: tegra: fix the wrong clock name
  cpuidle: Change struct menu_device field types
  cpuidle: Add a comment warning about possible overflow
  cpuidle: Fix variable domains in get_typical_interval()
  cpuidle: Fix menu_device-&gt;intervals type
  cpuidle: CodingStyle: Break up multiple assignments on single line
  cpuidle: Check called function parameter in get_typical_interval()
  ...
</content>
</entry>
<entry>
<title>driver/core: cpu: initialize of_node in cpu's device struture</title>
<updated>2013-08-21T09:29:30Z</updated>
<author>
<name>Sudeep KarkadaNagesha</name>
<email>sudeep.karkadanagesha@arm.com</email>
</author>
<published>2013-06-17T11:58:45Z</published>
<link rel='alternate' type='text/html' href='https://git.amat.us/linux/commit/?id=f86e4718f24b83be0c42894d2b97accc993d65d3'/>
<id>urn:sha1:f86e4718f24b83be0c42894d2b97accc993d65d3</id>
<content type='text'>
CPUs are also registered as devices but the of_node in these cpu
devices are not initialized. Currently different drivers requiring
to access cpu device node are parsing the nodes themselves and
initialising the of_node in cpu device.

The of_node in all the cpu devices needs to be initialized properly
and at one place. The best place to update this is CPU subsystem
driver when registering the cpu devices.

The OF/DT core library now provides of_get_cpu_node to retrieve a cpu
device node for a given logical index by abstracting the architecture
specific details.

This patch uses of_get_cpu_node to assign of_node when registering the
cpu devices.

Acked-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Acked-by: Rob Herring &lt;rob.herring@calxeda.com&gt;
Signed-off-by: Sudeep KarkadaNagesha &lt;sudeep.karkadanagesha@arm.com&gt;
</content>
</entry>
<entry>
<title>driver core / cpu: Check if NUMA node is valid before bringing CPU up</title>
<updated>2013-08-13T00:43:49Z</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2013-08-13T00:39:30Z</published>
<link rel='alternate' type='text/html' href='https://git.amat.us/linux/commit/?id=c7991b0b720efa5e0a590f6359d36e09bd187b76'/>
<id>urn:sha1:c7991b0b720efa5e0a590f6359d36e09bd187b76</id>
<content type='text'>
There is a potential race condition between cpu_subsys_online()
and either acpi_processor_remove() or remove_memory() that execute
try_offline_node().  Namely, it is possible that cpu_subsys_online()
will run right after the CPUs NUMA node has been put offline and
cpu_to_node() executed by it will return NUMA_NO_NODE (-1).  In
that case the CPU is gone and it doesn't make sense to call cpu_up()
for it, so make cpu_subsys_online() return -ENODEV then.

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Acked-by: Toshi Kani &lt;toshi.kani@hp.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>drivers: delete __cpuinit usage from all remaining drivers files</title>
<updated>2013-07-14T23:36:59Z</updated>
<author>
<name>Paul Gortmaker</name>
<email>paul.gortmaker@windriver.com</email>
</author>
<published>2013-06-19T19:22:41Z</published>
<link rel='alternate' type='text/html' href='https://git.amat.us/linux/commit/?id=a83048ebd449a441fdbd3fa854e6b1a71552cc99'/>
<id>urn:sha1:a83048ebd449a441fdbd3fa854e6b1a71552cc99</id>
<content type='text'>
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 remaining one-off uses of the __cpuinit macros
from all C files in the drivers/* directory.

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

Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Acked-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Paul Gortmaker &lt;paul.gortmaker@windriver.com&gt;
</content>
</entry>
<entry>
<title>Merge tag 'pm+acpi-3.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm</title>
<updated>2013-07-03T21:35:40Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2013-07-03T21:35:40Z</published>
<link rel='alternate' type='text/html' href='https://git.amat.us/linux/commit/?id=f991fae5c6d42dfc5029150b05a78cf3f6c18cc9'/>
<id>urn:sha1:f991fae5c6d42dfc5029150b05a78cf3f6c18cc9</id>
<content type='text'>
Pull power management and ACPI updates from Rafael Wysocki:
 "This time the total number of ACPI commits is slightly greater than
  the number of cpufreq commits, but Viresh Kumar (who works on cpufreq)
  remains the most active patch submitter.

  To me, the most significant change is the addition of offline/online
  device operations to the driver core (with the Greg's blessing) and
  the related modifications of the ACPI core hotplug code.  Next are the
  freezer updates from Colin Cross that should make the freezing of
  tasks a bit less heavy weight.

  We also have a couple of regression fixes, a number of fixes for
  issues that have not been identified as regressions, two new drivers
  and a bunch of cleanups all over.

  Highlights:

   - Hotplug changes to support graceful hot-removal failures.

     It sometimes is necessary to fail device hot-removal operations
     gracefully if they cannot be carried out completely.  For example,
     if memory from a memory module being hot-removed has been allocated
     for the kernel's own use and cannot be moved elsewhere, it's
     desirable to fail the hot-removal operation in a graceful way
     rather than to crash the kernel, but currenty a success or a kernel
     crash are the only possible outcomes of an attempted memory
     hot-removal.  Needless to say, that is not a very attractive
     alternative and it had to be addressed.

     However, in order to make it work for memory, I first had to make
     it work for CPUs and for this purpose I needed to modify the ACPI
     processor driver.  It's been split into two parts, a resident one
     handling the low-level initialization/cleanup and a modular one
     playing the actual driver's role (but it binds to the CPU system
     device objects rather than to the ACPI device objects representing
     processors).  That's been sort of like a live brain surgery on a
     patient who's riding a bike.

     So this is a little scary, but since we found and fixed a couple of
     regressions it caused to happen during the early linux-next testing
     (a month ago), nobody has complained.

     As a bonus we remove some duplicated ACPI hotplug code, because the
     ACPI-based CPU hotplug is now going to use the common ACPI hotplug
     code.

   - Lighter weight freezing of tasks.

     These changes from Colin Cross and Mandeep Singh Baines are
     targeted at making the freezing of tasks a bit less heavy weight
     operation.  They reduce the number of tasks woken up every time
     during the freezing, by using the observation that the freezer
     simply doesn't need to wake up some of them and wait for them all
     to call refrigerator().  The time needed for the freezer to decide
     to report a failure is reduced too.

     Also reintroduced is the check causing a lockdep warining to
     trigger when try_to_freeze() is called with locks held (which is
     generally unsafe and shouldn't happen).

   - cpufreq updates

     First off, a commit from Srivatsa S Bhat fixes a resume regression
     introduced during the 3.10 cycle causing some cpufreq sysfs
     attributes to return wrong values to user space after resume.  The
     fix is kind of fresh, but also it's pretty obvious once Srivatsa
     has identified the root cause.

     Second, we have a new freqdomain_cpus sysfs attribute for the
     acpi-cpufreq driver to provide information previously available via
     related_cpus.  From Lan Tianyu.

     Finally, we fix a number of issues, mostly related to the
     CPUFREQ_POSTCHANGE notifier and cpufreq Kconfig options and clean
     up some code.  The majority of changes from Viresh Kumar with bits
     from Jacob Shin, Heiko Stübner, Xiaoguang Chen, Ezequiel Garcia,
     Arnd Bergmann, and Tang Yuantian.

   - ACPICA update

     A usual bunch of updates from the ACPICA upstream.

     During the 3.4 cycle we introduced support for ACPI 5 extended
     sleep registers, but they are only supposed to be used if the
     HW-reduced mode bit is set in the FADT flags and the code attempted
     to use them without checking that bit.  That caused suspend/resume
     regressions to happen on some systems.  Fix from Lv Zheng causes
     those registers to be used only if the HW-reduced mode bit is set.

     Apart from this some other ACPICA bugs are fixed and code cleanups
     are made by Bob Moore, Tomasz Nowicki, Lv Zheng, Chao Guan, and
     Zhang Rui.

   - cpuidle updates

     New driver for Xilinx Zynq processors is added by Michal Simek.

     Multidriver support simplification, addition of some missing
     kerneldoc comments and Kconfig-related fixes come from Daniel
     Lezcano.

   - ACPI power management updates

     Changes to make suspend/resume work correctly in Xen guests from
     Konrad Rzeszutek Wilk, sparse warning fix from Fengguang Wu and
     cleanups and fixes of the ACPI device power state selection
     routine.

   - ACPI documentation updates

     Some previously missing pieces of ACPI documentation are added by
     Lv Zheng and Aaron Lu (hopefully, that will help people to
     uderstand how the ACPI subsystem works) and one outdated doc is
     updated by Hanjun Guo.

   - Assorted ACPI updates

     We finally nailed down the IA-64 issue that was the reason for
     reverting commit 9f29ab11ddbf ("ACPI / scan: do not match drivers
     against objects having scan handlers"), so we can fix it and move
     the ACPI scan handler check added to the ACPI video driver back to
     the core.

     A mechanism for adding CMOS RTC address space handlers is
     introduced by Lan Tianyu to allow some EC-related breakage to be
     fixed on some systems.

     A spec-compliant implementation of acpi_os_get_timer() is added by
     Mika Westerberg.

     The evaluation of _STA is added to do_acpi_find_child() to avoid
     situations in which a pointer to a disabled device object is
     returned instead of an enabled one with the same _ADR value.  From
     Jeff Wu.

     Intel BayTrail PCH (Platform Controller Hub) support is added to
     the ACPI driver for Intel Low-Power Subsystems (LPSS) and that
     driver is modified to work around a couple of known BIOS issues.
     Changes from Mika Westerberg and Heikki Krogerus.

     The EC driver is fixed by Vasiliy Kulikov to use get_user() and
     put_user() instead of dereferencing user space pointers blindly.

     Code cleanups are made by Bjorn Helgaas, Nicholas Mazzuca and Toshi
     Kani.

   - Assorted power management updates

     The "runtime idle" helper routine is changed to take the return
     values of the callbacks executed by it into account and to call
     rpm_suspend() if they return 0, which allows us to reduce the
     overall code bloat a bit (by dropping some code that's not
     necessary any more after that modification).

     The runtime PM documentation is updated by Alan Stern (to reflect
     the "runtime idle" behavior change).

     New trace points for PM QoS are added by Sahara
     (&lt;keun-o.park@windriver.com&gt;).

     PM QoS documentation is updated by Lan Tianyu.

     Code cleanups are made and minor issues are addressed by Bernie
     Thompson, Bjorn Helgaas, Julius Werner, and Shuah Khan.

   - devfreq updates

     New driver for the Exynos5-bus device from Abhilash Kesavan.

     Minor cleanups, fixes and MAINTAINERS update from MyungJoo Ham,
     Abhilash Kesavan, Paul Bolle, Rajagopal Venkat, and Wei Yongjun.

   - OMAP power management updates

     Adaptive Voltage Scaling (AVS) SmartReflex voltage control driver
     updates from Andrii Tseglytskyi and Nishanth Menon."

* tag 'pm+acpi-3.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (162 commits)
  cpufreq: Fix cpufreq regression after suspend/resume
  ACPI / PM: Fix possible NULL pointer deref in acpi_pm_device_sleep_state()
  PM / Sleep: Warn about system time after resume with pm_trace
  cpufreq: don't leave stale policy pointer in cdbs-&gt;cur_policy
  acpi-cpufreq: Add new sysfs attribute freqdomain_cpus
  cpufreq: make sure frequency transitions are serialized
  ACPI: implement acpi_os_get_timer() according the spec
  ACPI / EC: Add HP Folio 13 to ec_dmi_table in order to skip DSDT scan
  ACPI: Add CMOS RTC Operation Region handler support
  ACPI / processor: Drop unused variable from processor_perflib.c
  cpufreq: tegra: call CPUFREQ_POSTCHANGE notfier in error cases
  cpufreq: s3c64xx: call CPUFREQ_POSTCHANGE notfier in error cases
  cpufreq: omap: call CPUFREQ_POSTCHANGE notfier in error cases
  cpufreq: imx6q: call CPUFREQ_POSTCHANGE notfier in error cases
  cpufreq: exynos: call CPUFREQ_POSTCHANGE notfier in error cases
  cpufreq: dbx500: call CPUFREQ_POSTCHANGE notfier in error cases
  cpufreq: davinci: call CPUFREQ_POSTCHANGE notfier in error cases
  cpufreq: arm-big-little: call CPUFREQ_POSTCHANGE notfier in error cases
  cpufreq: powernow-k8: call CPUFREQ_POSTCHANGE notfier in error cases
  cpufreq: pcc: call CPUFREQ_POSTCHANGE notfier in error cases
  ...
</content>
</entry>
<entry>
<title>CPU: Fix sysfs cpu/online of offlined CPUs</title>
<updated>2013-05-29T22:30:05Z</updated>
<author>
<name>Toshi Kani</name>
<email>toshi.kani@hp.com</email>
</author>
<published>2013-05-29T22:30:05Z</published>
<link rel='alternate' type='text/html' href='https://git.amat.us/linux/commit/?id=1001b4d4a8ee6b2e7a6078a02ccdf68f91b192bd'/>
<id>urn:sha1:1001b4d4a8ee6b2e7a6078a02ccdf68f91b192bd</id>
<content type='text'>
As reported by Dave Hansen, sysfs cpu/online shows 1 for
offlined CPUs at boot.

Fix this problem by initializing dev.offline with cpu_online()
when registering a CPU.

References: https://lkml.org/lkml/2013/5/29/403
Reported-and-tested-by: Dave Hansen &lt;dave.hansen@intel.com&gt;
Signed-off-by: Toshi Kani &lt;toshi.kani@hp.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
</entry>
<entry>
<title>cpu: make sure that cpu/online file created before KOBJ_ADD is emitted</title>
<updated>2013-05-21T17:15:40Z</updated>
<author>
<name>Igor Mammedov</name>
<email>imammedo@redhat.com</email>
</author>
<published>2013-05-14T14:46:07Z</published>
<link rel='alternate' type='text/html' href='https://git.amat.us/linux/commit/?id=1c4e2d70afb132058bfe979f6854c1d0a732b556'/>
<id>urn:sha1:1c4e2d70afb132058bfe979f6854c1d0a732b556</id>
<content type='text'>
It fixes race between udev and hotplugged CPU registration by defining
"online" attribute statically, so that device_add() would create it
before notifying udev about new CPU.

Original issue report is at https://lkml.org/lkml/2012/4/30/198
"
&gt; On Mon, Apr 30, 2012 at 11:36:23AM -0400, Konrad Rzeszutek Wilk wrote:
&gt; &gt; Hey Greg,
&gt; &gt;
&gt; &gt; Hoping you can help with some guidance on how to fix this.
&gt; &gt;
&gt; &gt; The issue is with CPU hotplug is that when a CPU goes up
&gt; &gt; it calls 'arch_register_cpu' which eventually calls
&gt; &gt; register_cpu. That function does these two things:
&gt; &gt;
&gt; &gt; 251         error = device_register(&amp;cpu-&gt;dev);
&gt; &gt; 252         if (!error &amp;&amp; cpu-&gt;hotpluggable)
&gt; &gt; 253                 register_cpu_control(cpu);
&gt; &gt;
&gt; &gt; and the device_register creates a nice little SysFS directory:
&gt; &gt;
&gt; &gt; /sys/devices/system/cpu/cpu2/ which at line 251 has the 'add' attribute
&gt; &gt; but no 'online' attribute. udev then tries to echo 1 to the 'online'
&gt; &gt; and it we get:
&gt; &gt; udevd-work[2421]: error opening ATTR{/sys/devices/system/cpu/cpu2/online} for writing: No such file or directory
&gt; &gt;
&gt; &gt; Line 253 creates said 'online' and at that time udev [or the system admin]
&gt; &gt; can write 1 to 'online' and the CPU goes up.
&gt; &gt;
&gt; &gt; So .. any thoughts? Is there some way to inhibit from uevent being sent
&gt; &gt; until line 253 has run?
"

Signed-off-by: Igor Mammedov &lt;imammedo@redhat.com&gt;
Tested-by: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.com&gt;
Reviewed-by: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>cpu: fix "crash_notes" and "crash_notes_size" leaks in register_cpu()</title>
<updated>2013-05-21T17:14:40Z</updated>
<author>
<name>Igor Mammedov</name>
<email>imammedo@redhat.com</email>
</author>
<published>2013-05-14T14:46:06Z</published>
<link rel='alternate' type='text/html' href='https://git.amat.us/linux/commit/?id=c055da9fbad4b63bb3169f2b1a8b7ad429270bd0'/>
<id>urn:sha1:c055da9fbad4b63bb3169f2b1a8b7ad429270bd0</id>
<content type='text'>
"crash_notes" and "crash_notes_size" are dynamically created
with device_create_file() but aren't deleted anywhere.
Define "crash_notes" and "crash_notes_size" statically via
attribute groups so that device_register would create them
automatically and files would be destroyed when CPU is destroyed.

Signed-off-by: Igor Mammedov &lt;imammedo@redhat.com&gt;
Tested-by: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.com&gt;
Reviewed-by: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>ACPI / processor: Use common hotplug infrastructure</title>
<updated>2013-05-12T12:14:32Z</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2013-05-02T22:26:22Z</published>
<link rel='alternate' type='text/html' href='https://git.amat.us/linux/commit/?id=ac212b6980d8d5eda705864fc5a8ecddc6d6eacc'/>
<id>urn:sha1:ac212b6980d8d5eda705864fc5a8ecddc6d6eacc</id>
<content type='text'>
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 &lt;rafael.j.wysocki@intel.com&gt;
Acked-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Reviewed-by: Toshi Kani &lt;toshi.kani@hp.com&gt;
</content>
</entry>
<entry>
<title>Driver core: Use generic offline/online for CPU offline/online</title>
<updated>2013-05-12T12:14:17Z</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2013-05-02T22:25:49Z</published>
<link rel='alternate' type='text/html' href='https://git.amat.us/linux/commit/?id=0902a9044fa5b7a0456ea4daacec2c2b3189ba8c'/>
<id>urn:sha1:0902a9044fa5b7a0456ea4daacec2c2b3189ba8c</id>
<content type='text'>
Rework the CPU hotplug code in drivers/base/cpu.c to use the
generic offline/online support introduced previously instead of
its own CPU-specific code.

For this purpose, modify cpu_subsys to provide offline and online
callbacks for CONFIG_HOTPLUG_CPU set and remove the code handling
the CPU-specific 'online' sysfs attribute.

This modification is not supposed to change the user-observable
behavior of the kernel (i.e. the 'online' attribute will be present
in exactly the same place in sysfs and should trigger exactly the
same actions as before).

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Acked-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Reviewed-by: Toshi Kani &lt;toshi.kani@hp.com&gt;
</content>
</entry>
</feed>
