Commit Graph

54 Commits

Author SHA1 Message Date
Andreas Schwab a857c0b9e2 cpufreq: Fix wrong time unit conversion
The time spent by a CPU under a given frequency is stored in jiffies unit
in the cpu var cpufreq_stats_table->time_in_state[i], i being the index of
the frequency.

This is what is displayed in the following file on the right column:

     cat /sys/devices/system/cpu/cpuX/cpufreq/stats/time_in_state
     2301000 19835820
     2300000 3172
     [...]

Now cpufreq converts this jiffies unit delta to clock_t before returning it
to the user as in the above file. And that conversion is achieved using the API
cputime64_to_clock_t().

Although it accidentally works on traditional tick based cputime accounting, where
cputime_t maps directly to jiffies, it doesn't work with other types of cputime
accounting such as CONFIG_VIRT_CPU_ACCOUNTING_* where cputime_t can map to nsecs
or any granularity preffered by the architecture.

For example we get a buggy zero delta on full dyntick configurations:

     cat /sys/devices/system/cpu/cpuX/cpufreq/stats/time_in_state
     2301000 0
     2300000 0
     [...]

Fix this with using the proper jiffies_64_t to clock_t conversion.

Reported-and-tested-by: Carsten Emde <C.Emde@osadl.org>
Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-10 02:49:46 +02:00
Viresh Kumar d5b73cd870 cpufreq: Use sizeof(*ptr) convetion for computing sizes
Chapter 14 of Documentation/CodingStyle says:

The preferred form for passing a size of a struct is the following:

	p = kmalloc(sizeof(*p), ...);

The alternative form where struct name is spelled out hurts
readability and introduces an opportunity for a bug when the pointer
variable type is changed but the corresponding sizeof that is passed
to a memory allocator is not.

This wasn't followed consistently in drivers/cpufreq, let's make it
more consistent by always following this rule.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07 23:34:10 +02:00
Viresh Kumar 3a3e9e06d0 cpufreq: Give consistent names to cpufreq_policy objects
They are called policy, cur_policy, new_policy, data, etc.  Just call
them policy wherever possible.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07 23:34:10 +02:00
Viresh Kumar 5ff0a26803 cpufreq: Clean up header files included in the core
This patch addresses the following issues in the header files in the
cpufreq core:
 - Include headers in ascending order, so that we don't add same
   many times by mistake.
 - <asm/> must be included after <linux/>, so that they override
   whatever they need to.
 - Remove unnecessary includes.
 - Don't include files already included by cpufreq.h or
   cpufreq_governor.h.

[rjw: Changelog]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07 23:34:09 +02:00
Srivatsa S. Bhat 5302c3fb2e cpufreq: Perform light-weight init/teardown during suspend/resume
Now that we have the infrastructure to perform a light-weight init/tear-down,
use that in the cpufreq CPU hotplug notifier when invoked from the
suspend/resume path.

This also ensures that the file permissions of the cpufreq sysfs files are
preserved across suspend/resume, something which commit a66b2e (cpufreq:
Preserve sysfs files across suspend/resume) originally intended to do, but
had to be reverted due to other problems.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07 23:02:49 +02:00
Srivatsa S. Bhat 23d328994b cpufreq: Fix misplaced call to cpufreq_update_policy()
The call to cpufreq_update_policy() is placed in the CPU hotplug callback
of cpufreq_stats, which has a higher priority than the CPU hotplug callback
of cpufreq-core. As a result, during CPU_ONLINE/CPU_ONLINE_FROZEN, we end up
calling cpufreq_update_policy() *before* calling cpufreq_add_dev() !
And for uninitialized CPUs, it just returns silently, not doing anything.

To add to that, cpufreq_stats is not even the right place to call
cpufreq_update_policy() to begin with. The cpufreq core ought to handle
this in its own callback, from an elegance/relevance perspective.

So move the invocation of cpufreq_update_policy() to cpufreq_cpu_callback,
and place it *after* cpufreq_add_dev().

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-07 23:02:48 +02:00
Linus Torvalds b7356abb9f Power management and ACPI fixes for 3.11-rc2
- Two cpufreq commits from the 3.10 cycle introduced regressions.
   The first of them was buggy (it did way much more than it needed
   to do) and the second one attempted to fix an issue introduced by
   the first one.  Fixes from Srivatsa S Bhat revert both.
 
 - If autosleep triggers during system shutdown and the shutdown
   callbacks of some device drivers have been called already, it may
   crash the system.  Fix from Liu Shuo prevents that from happening
   by making try_to_suspend() check system_state.
 
 - The ACPI memory hotplug driver doesn't clear its driver_data on
   errors which may cause a NULL poiter dereference to happen later.
   Fix from Toshi Kani.
 
 - The ACPI namespace scanning code should not try to attach scan
   handlers to device objects that have them already, which may confuse
   things quite a bit, and it should rescan the whole namespace branch
   starting at the given node after receiving a bus check notify event
   even if the device at that particular node has been discovered
   already.  Fixes from Rafael J Wysocki.
 
 - New ACPI video blacklist entry for a system whose initial backlight
   setting from the BIOS doesn't make sense.  From Lan Tianyu.
 
 - Garbage string output avoindance for ACPI PNP from Liu Shuo.
 
 - Two Kconfig fixes for issues introduced recently in the s3c24xx
   cpufreq driver (when moving the driver to drivers/cpufreq) from
   Paul Bolle.
 
 - Trivial comment fix in pm_wakeup.h from Chanwoo Choi.
 
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Merge tag 'pm+acpi-3.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management and ACPI fixes from Rafael Wysocki:
 "These are fixes collected over the last week, most importnatly two
  cpufreq reverts fixing regressions introduced in 3.10, an autoseelp
  fix preventing systems using it from crashing during shutdown and two
  ACPI scan fixes related to hotplug.

  Specifics:

   - Two cpufreq commits from the 3.10 cycle introduced regressions.
     The first of them was buggy (it did way much more than it needed to
     do) and the second one attempted to fix an issue introduced by the
     first one.  Fixes from Srivatsa S Bhat revert both.

   - If autosleep triggers during system shutdown and the shutdown
     callbacks of some device drivers have been called already, it may
     crash the system.  Fix from Liu Shuo prevents that from happening
     by making try_to_suspend() check system_state.

   - The ACPI memory hotplug driver doesn't clear its driver_data on
     errors which may cause a NULL poiter dereference to happen later.
     Fix from Toshi Kani.

   - The ACPI namespace scanning code should not try to attach scan
     handlers to device objects that have them already, which may
     confuse things quite a bit, and it should rescan the whole
     namespace branch starting at the given node after receiving a bus
     check notify event even if the device at that particular node has
     been discovered already.  Fixes from Rafael J Wysocki.

   - New ACPI video blacklist entry for a system whose initial backlight
     setting from the BIOS doesn't make sense.  From Lan Tianyu.

   - Garbage string output avoindance for ACPI PNP from Liu Shuo.

   - Two Kconfig fixes for issues introduced recently in the s3c24xx
     cpufreq driver (when moving the driver to drivers/cpufreq) from
     Paul Bolle.

   - Trivial comment fix in pm_wakeup.h from Chanwoo Choi"

* tag 'pm+acpi-3.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / video: ignore BIOS initial backlight value for Fujitsu E753
  PNP / ACPI: avoid garbage in resource name
  cpufreq: Revert commit 2f7021a8 to fix CPU hotplug regression
  cpufreq: s3c24xx: fix "depends on ARM_S3C24XX" in Kconfig
  cpufreq: s3c24xx: rename CONFIG_CPU_FREQ_S3C24XX_DEBUGFS
  PM / Sleep: Fix comment typo in pm_wakeup.h
  PM / Sleep: avoid 'autosleep' in shutdown progress
  cpufreq: Revert commit a66b2e to fix suspend/resume regression
  ACPI / memhotplug: Fix a stale pointer in error path
  ACPI / scan: Always call acpi_bus_scan() for bus check notifications
  ACPI / scan: Do not try to attach scan handlers to devices having them
2013-07-19 09:59:06 -07:00
Paul Gortmaker 2760984f65 cpufreq: delete __cpuinit usage from all cpufreq 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/cpufreq uses of the __cpuinit macros
from all C files.

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

[v2: leave 2nd lines of args misaligned as requested by Viresh]
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: cpufreq@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Acked-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-07-14 19:36:57 -04:00
Srivatsa S. Bhat aae760ed21 cpufreq: Revert commit a66b2e to fix suspend/resume regression
commit a66b2e (cpufreq: Preserve sysfs files across suspend/resume)
has unfortunately caused several things in the cpufreq subsystem to
break subtly after a suspend/resume cycle.

The intention of that patch was to retain the file permissions of the
cpufreq related sysfs files across suspend/resume.  To achieve that,
the commit completely removed the calls to cpufreq_add_dev() and
__cpufreq_remove_dev() during suspend/resume transitions.  But the
problem is that those functions do 2 kinds of things:
  1. Low-level initialization/tear-down that are critical to the
     correct functioning of cpufreq-core.
  2. Kobject and sysfs related initialization/teardown.

Ideally we should have reorganized the code to cleanly separate these
two responsibilities, and skipped only the sysfs related parts during
suspend/resume.  Since we skipped the entire callbacks instead (which
also included some CPU and cpufreq-specific critical components),
cpufreq subsystem started behaving erratically after suspend/resume.

So revert the commit to fix the regression.  We'll revisit and address
the original goal of that commit separately, since it involves quite a
bit of careful code reorganization and appears to be non-trivial.

(While reverting the commit, note that another commit f51e1eb
 (cpufreq: Fix cpufreq regression after suspend/resume) already
 reverted part of the original set of changes.  So revert only the
 remaining ones).

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Paul Bolle <pebolle@tiscali.nl>
Cc: 3.10+ <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-15 01:31:36 +02:00
Srivatsa S. Bhat f51e1eb63d cpufreq: Fix cpufreq regression after suspend/resume
Toralf Förster reported that the cpufreq ondemand governor behaves erratically
(doesn't scale well) after a suspend/resume cycle. The problem was that the
cpufreq subsystem's idea of the cpu frequencies differed from the actual
frequencies set in the hardware after a suspend/resume cycle. Toralf bisected
the problem to commit a66b2e5 (cpufreq: Preserve sysfs files across
suspend/resume).

Among other (harmless) things, that commit skipped the call to
cpufreq_update_policy() in the resume path. But cpufreq_update_policy() plays
an important role during resume, because it is responsible for checking if
the BIOS changed the cpu frequencies behind our back and resynchronize the
cpufreq subsystem's knowledge of the cpu frequencies, and update them
accordingly.

So, restore the call to cpufreq_update_policy() in the resume path to fix
the cpufreq regression.

Reported-and-tested-by: Toralf Förster <toralf.foerster@gmx.de>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: 3.10+ <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-01 00:40:55 +02:00
Viresh Kumar bb176f7d03 cpufreq: Fix minor formatting issues
There were a few noticeable formatting issues in core cpufreq code.
This cleans them up to make code look better.  The changes include:
 - Whitespace cleanup.
 - Rearrangements of code.
 - Multiline comments fixes.
 - Formatting changes to fit 80 columns.

Copyright information in cpufreq.c is also updated to include my name
for 2013.

[rjw: Changelog]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-06-21 01:06:34 +02:00
Srivatsa S. Bhat a66b2e503f cpufreq: Preserve sysfs files across suspend/resume
The file permissions of cpufreq per-cpu sysfs files are not preserved
across suspend/resume because we internally go through the CPU
Hotplug path which reinitializes the file permissions on CPU online.

But the user is not supposed to know that we are using CPU hotplug
internally within suspend/resume (IOW, the kernel should not silently
wreck the user-set file permissions across a suspend cycle).
Therefore, we need to preserve the file permissions as they are
across suspend/resume.

The simplest way to achieve that is to just not touch the sysfs files
at all - ie., just ignore the CPU hotplug notifications in the
suspend/resume path (_FROZEN) in the cpufreq hotplug callback.

Reported-by: Robert Jarzmik <robert.jarzmik@intel.com>
Reported-by: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-05-15 21:47:17 +02:00
viresh kumar 187da1d97f cpufreq: stats: do cpufreq_cpu_put() corresponding to cpufreq_cpu_get()
In cpufreq_stats_free_sysfs() we aren't balancing calls to
cpufreq_cpu_get() with cpufreq_cpu_put(). This will never let us have
ref count to policy->kobj as zero.

We will get a hang if somehow cpufreq_driver_unregister() is called.
And that can happen when we compile our driver as module and
insmod/rmmod it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Amit Kucheria <amit.kucheria@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-25 15:13:16 +01:00
Dirk Brandewie 633d47d653 cpufreq_stats: do not remove sysfs files if frequency table is not present
The sysfs files for cpufreq_stats are created in cpufreq_stats_create_table()
called from cpufreq_stat_notifier_policy() when a policy is added to
the cpu. cpufreq_stats_create_table() will not be called if the
scaling driver does not export a frequency table to cpufreq.  Use the
same fence on tear down.

Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-09 12:55:59 +01:00
Viresh Kumar df18e504aa cpufreq / stats: Get rid of CPUFREQ_STATDEVICE_ATTR
Macro "CPUFREQ_STATDEVICE_ATTR" is defined local to cpufreq_stats.c file and is
almost a copy of the generic version present in cpufreq.h file. Lets use the
generic version instead.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-09 01:18:40 +01:00
Fabio Baltieri 2624f90c16 cpufreq: governors: implement generic policy_is_shared
Implement a generic helper function policy_is_shared() to replace the
current dbs_sw_coordinated_cpus() at cpufreq level, so that it can be
used by code other than cpufreq governors.

Suggested-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Fabio Baltieri <fabio.baltieri@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-02 00:01:16 +01:00
Viresh Kumar b8eed8af94 cpufreq: Simplify __cpufreq_remove_dev()
__cpufreq_remove_dev() is called on multiple occasions: cpufreq_driver
unregister and cpu removals.

Current implementation of this routine is overly complex without much need. If
the cpu to be removed is the policy->cpu, we remove the policy first and add all
other cpus again from policy->cpus and then finally call __cpufreq_remove_dev()
again to remove the cpu to be deleted. Haahhhh..

There exist a simple solution to removal of a cpu:
- Simply use the old policy structure
- update its fields like: policy->cpu, etc.
- notify any users of cpufreq, which depend on changing policy->cpu

Hence this patch, which tries to implement the above theory. It is tested well
by myself on ARM big.LITTLE TC2 SoC, which has 5 cores (2 A15 and 3 A7). Both
A15's share same struct policy and all A7's share same policy structure.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-02 00:01:14 +01:00
Konstantin Khlebnikov 56836fb4da cpufreq / stats: fix race between stats allocation and first usage
This patch forces complete struct cpufreq_stats allocation for all cpus before
registering CPUFREQ_TRANSITION_NOTIFIER notifier, otherwise in some conditions
cpufreq_stat_notifier_trans() can be called in the middle of stats allocation,
in this case cpufreq_stats_table already exists, but stat->freq_table is NULL.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-03 13:11:18 +01:00
Viresh Kumar 1e7586a18a cpufreq: Fix sparse warnings by updating cputime64_t to u64
There were few sparse warnings due to mismatch of type on function arguments.
Two types were used u64 and cputime64_t. Both are actually u64, so use u64 only.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-15 00:33:08 +01:00
Tu, Xiaobing e377367772 Fix memory leak in cpufreq stats.
When system enters sleep, non-boot CPUs will be disabled.
Cpufreq stats sysfs is created when the CPU is up, but it is not
freed when the CPU is going down. This will cause memory leak.

Signed-off-by: xiaobing tu <xiaobing.tu@intel.com>
Signed-off-by: guifang tang <guifang.tang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-10-23 01:03:00 +02:00
Linus Torvalds 7affca3537 Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (73 commits)
  arm: fix up some samsung merge sysdev conversion problems
  firmware: Fix an oops on reading fw_priv->fw in sysfs loading file
  Drivers:hv: Fix a bug in vmbus_driver_unregister()
  driver core: remove __must_check from device_create_file
  debugfs: add missing #ifdef HAS_IOMEM
  arm: time.h: remove device.h #include
  driver-core: remove sysdev.h usage.
  clockevents: remove sysdev.h
  arm: convert sysdev_class to a regular subsystem
  arm: leds: convert sysdev_class to a regular subsystem
  kobject: remove kset_find_obj_hinted()
  m86k: gpio - convert sysdev_class to a regular subsystem
  mips: txx9_sram - convert sysdev_class to a regular subsystem
  mips: 7segled - convert sysdev_class to a regular subsystem
  sh: dma - convert sysdev_class to a regular subsystem
  sh: intc - convert sysdev_class to a regular subsystem
  power: suspend - convert sysdev_class to a regular subsystem
  power: qe_ic - convert sysdev_class to a regular subsystem
  power: cmm - convert sysdev_class to a regular subsystem
  s390: time - convert sysdev_class to a regular subsystem
  ...

Fix up conflicts with 'struct sysdev' removal from various platform
drivers that got changed:
 - arch/arm/mach-exynos/cpu.c
 - arch/arm/mach-exynos/irq-eint.c
 - arch/arm/mach-s3c64xx/common.c
 - arch/arm/mach-s3c64xx/cpu.c
 - arch/arm/mach-s5p64x0/cpu.c
 - arch/arm/mach-s5pv210/common.c
 - arch/arm/plat-samsung/include/plat/cpu.h
 - arch/powerpc/kernel/sysfs.c
and fix up cpu_is_hotpluggable() as per Greg in include/linux/cpu.h
2012-01-07 12:03:30 -08:00
Kay Sievers 8a25a2fd12 cpu: convert 'cpu' and 'machinecheck' sysdev_class to a regular subsystem
This moves the 'cpu sysdev_class' over to a regular 'cpu' subsystem
and converts the devices to regular devices. The sysdev drivers are
implemented as subsystem interfaces now.

After all sysdev classes are ported to regular driver core entities, the
sysdev implementation will be entirely removed from the kernel.

Userspace relies on events and generic sysfs subsystem infrastructure
from sysdev devices, which are made available with this conversion.

Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Borislav Petkov <bp@amd64.org>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Cc: Len Brown <lenb@kernel.org>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-12-21 14:29:42 -08:00
Martin Schwidefsky 648616343c [S390] cputime: add sparse checking and cleanup
Make cputime_t and cputime64_t nocast to enable sparse checking to
detect incorrect use of cputime. Drop the cputime macros for simple
scalar operations. The conversion macros are still needed.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-12-15 14:56:19 +01:00
Paul Gortmaker 5c720d37bf cpufreq: cpufreq_stats.c is a module, and should include module.h
So that we can clean up the header files and not be relying
on implicit includes from device.h ---> module.h

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:31:31 -04:00
Konrad Rzeszutek Wilk 46a310b80b [CPUFREQ] Don't set stat->last_index to -1 if the pol->cur has incorrect value.
If the driver submitted an non-existing pol>cur value (say it
used the default initialized value of zero), when the cpufreq
stats tries to setup its initial values it incorrectly sets
stat->last_index to -1 (or 0xfffff...). And cpufreq_stats_update
tries to update at that index location and fails.

This can be caused by:

stat->last_index = freq_table_get_index(stat, policy->cur);

not finding the appropiate frequency in the table (b/c the policy->cur
is wrong) and we end up crashing. The fix however is
concentrated in the 'cpufreq_stats_update' as the last_index
(and old_index) are updated there. Which means it can reset
the last_index to -1 again and on the next iteration cause a crash.

Without this patch, the following crash is observed:

powernow-k8: Found 1 AMD Athlon(tm) 64 Processor 3700+ (1 cpu cores) (version 2.20.00)
powernow-k8: fid 0x2 (1000 MHz), vid 0x12
powernow-k8: fid 0xa (1800 MHz), vid 0xa
powernow-k8: fid 0xc (2000 MHz), vid 0x8
powernow-k8: fid 0xe (2200 MHz), vid 0x8
Marking TSC unstable due to cpufreq changes
powernow-k8: fid trans failed, fid 0x2, curr 0x0
BUG: unable to handle kernel paging request at ffff880807e07b78
IP: [<ffffffff81479163>] cpufreq_stats_update+0x46/0x5b
.. snip..
Pid: 1, comm: swapper Not tainted 3.0.0-rc2 #45 MICRO-STAR INTERNATIONAL CO., LTD MS-7094/MS-7094
..snip..
Call Trace:
 [<ffffffff81479248>] cpufreq_stat_notifier_trans+0x48/0x7c
 [<ffffffff81095d68>] notifier_call_chain+0x32/0x5e
 [<ffffffff81095e6b>] __srcu_notifier_call_chain+0x47/0x63
 [<ffffffff81095e96>] srcu_notifier_call_chain+0xf/0x11
 [<ffffffff81477e7a>] cpufreq_notify_transition+0x111/0x134
 [<ffffffff8147b0d4>] powernowk8_target+0x53b/0x617
 [<ffffffff8147723a>] __cpufreq_driver_target+0x2e/0x30
 [<ffffffff8147a127>] cpufreq_governor_dbs+0x339/0x356
 [<ffffffff81477394>] __cpufreq_governor+0xa8/0xe9
 [<ffffffff81477525>] __cpufreq_set_policy+0x132/0x13e
 [<ffffffff8147848d>] cpufreq_add_dev_interface+0x272/0x28c

Reported-by: Tobias Diedrich <ranma+xen@tdiedrich.de>
Tested-by: Tobias Diedrich <ranma+xen@tdiedrich.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2011-06-16 16:31:12 -04:00
Dave Jones 13f067537f [CPUFREQ] Remove cpufreq_stats sysfs entries on module unload.
cpufreq_stats leaves behind its sysfs entries, which causes a panic
when something stumbled across them.
(Discovered by unloading cpufreq_stats while powertop was loaded).

Signed-off-by: Dave Jones <davej@redhat.com>
Cc: stable@kernel.org
2011-06-12 16:36:52 -04:00
Karthigan Srinivasan 469057d587 [CPUFREQ] cpufreq_stats.c: Fixed brace coding style issue
Fixed brace coding style issue.

Signed-off-by: Karthigan Srinivasan <karthigan.srinivasan@hp.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2011-05-04 11:50:58 -04:00
steven finney 98586ed8b8 [CPUFREQ] Fix memory leak in cpufreq_stat
When a CPU is taken offline in an SMP system, cpufreq_remove_dev()
nulls out the per-cpu policy before cpufreq_stats_free_table() can
make use of it.  cpufreq_stats_free_table() then skips the
call to sysfs_remove_group(), leaving about 100 bytes of sysfs-related
memory unclaimed each time a CPU-removal occurs. Break up
cpu_stats_free_table into sysfs and table portions, and
call the sysfs portion early.

Signed-off-by: Steven Finney <steven.finney@palm.com>
Signed-off-by: Dave Jones <davej@redhat.com>
Cc: stable@kernel.org
2011-05-04 11:50:57 -04:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Dave Jones 0a829c5afd [CPUFREQ] checkpatch cleanups for cpufreq_stats
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:30 -05:00
Mike Travis 7a6aedfac9 [CPUFREQ] change cpu freq arrays to per_cpu variables
Change cpufreq_policy and cpufreq_governor pointer tables
from arrays to per_cpu variables in the cpufreq subsystem.

Also some minor complaints from checkpatch.pl fixed.

Based on:
	git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
	git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86.git

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-05-19 18:17:49 -04:00
Shaohua Li 6501faf8c1 [CPUFREQ] state info wrong after resume
Sometimes old_index != stat->last_index, see cpufreq_update_policy, bios can
change cpu setting in resume.  In my test, after resume cpu is in lowest
speed, but the stat info shows cpu is in full speed.  This patch makes the
stat info correct after a resume.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-04-28 16:27:08 -04:00
Cesar Eduardo Barros 25aca347d4 [CPUFREQ] fix show_trans_table
Fix show_trans_table when it overflows PAGE_SIZE.

* Not all snprintf calls were protected against being passed a negative
length.
* When show_trans_table overflows, len might be > PAGE_SIZE. In that case,
returns PAGE_SIZE.

Signed-off-by: Cesar Eduardo Barros <cesarb@cesarb.net>
Signed-off-by: Dave Jones <davej@codemonkey.org.uk>
2008-04-28 15:05:44 -04:00
Sam Ravnborg f6ebef30e2 [CPUFREQ] fix section mismatch warnings
Fix the following warnings:
WARNING: vmlinux.o(.text+0xfe6711): Section mismatch in reference from the function cpufreq_unregister_driver() to the variable .cpuinit.data:cpufreq_cpu_notifier
WARNING: vmlinux.o(.text+0xfe68af): Section mismatch in reference from the function cpufreq_register_driver() to the variable .cpuinit.data:cpufreq_cpu_notifier
WARNING: vmlinux.o(.exit.text+0xc4fa): Section mismatch in reference from the function cpufreq_stats_exit() to the variable .cpuinit.data:cpufreq_stat_cpu_notifier

The warnings were casued by references to unregister_hotcpu_notifier()
from normal functions or exit functions.
This is flagged by modpost as a potential error because
it does not know that for the non HOTPLUG_CPU
scenario the unregister_hotcpu_notifier() is a nop.
Silence the warning by replacing the __initdata
annotation with a __refdata annotation.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Dave Jones <davej@codemonkey.org.uk>
2008-03-05 14:45:31 -05:00
Adrian Bunk a33234735b drivers/cpufreq/cpufreq_stats.c section fix
cpufreq_stats_free_table() mustn't be __cpuexit since it's called by the
__cpuinit cpufreq_stat_cpu_callback().

This patch fixes the following section mismatch reported by
Chris Clayton:

WARNING: vmlinux.o(.init.text+0x143dd): Section mismatch: reference to .exit.text:cpufreq_stats_free_table (between 'cpufreq_stat_cpu_callback' and 'cpufreq_stats_init')

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Chris Clayton <chris2553@googlemail.com>
Acked-by: Dave Jones <davej@codemonkey.org.uk>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-17 19:28:16 -08:00
Satyam Sharma 55395ae72b [CPUFREQ] cpufreq_stats: misc cpuinit section annotations
* Stop referencing the callback directly from the __init and __exit
  functions of this driver, and instead explicitly call
  cpufreq_update_policy() et al. This enables the callback function
  to be marked as __cpuinit (and the notifier_block __cpuinitdata),
  thereby saving space when HOTPLUG_CPU=n. This also enables us to
  use other tricks to replace __cpuinit{data} in future.

* cpufreq_stats_free_table() is only called from __cpuinit or __exit
  marked functions, making it an ideal candidate for __cpuexit.

* Fix missing space in the module description

Signed-off-by: Satyam Sharma <satyam@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-10-04 18:40:57 -04:00
Tejun Heo 7b595756ec sysfs: kill unnecessary attribute->owner
sysfs is now completely out of driver/module lifetime game.  After
deletion, a sysfs node doesn't access anything outside sysfs proper,
so there's no reason to hold onto the attribute owners.  Note that
often the wrong modules were accounted for as owners leading to
accessing removed modules.

This patch kills now unnecessary attribute->owner.  Note that with
this change, userland holding a sysfs node does not prevent the
backing module from being unloaded.

For more info regarding lifetime rule cleanup, please read the
following message.

  http://article.gmane.org/gmane.linux.kernel/510293

(tweaked by Greg to not delete the field just yet, to make it easier to
merge things properly.)

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-11 16:09:06 -07:00
Rafael J. Wysocki 8bb7844286 Add suspend-related notifications for CPU hotplug
Since nonboot CPUs are now disabled after tasks and devices have been
frozen and the CPU hotplug infrastructure is used for this purpose, we need
special CPU hotplug notifications that will help the CPU-hotplug-aware
subsystems distinguish normal CPU hotplug events from CPU hotplug events
related to a system-wide suspend or resume operation in progress.  This
patch introduces such notifications and causes them to be used during
suspend and resume transitions.  It also changes all of the
CPU-hotplug-aware subsystems to take these notifications into consideration
(for now they are handled in the same way as the corresponding "normal"
ones).

[oleg@tv-sign.ru: cleanups]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-09 12:30:56 -07:00
Dave Jones c120069779 [CPUFREQ] Remove hotplug cpu crap
The hotplug CPU locking in cpufreq is horrendous.  No-one seems to care
enough to fix it, so just remove it so that the 99.9% of the real world
users of this code can use cpufreq without being bothered by warnings.

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-02-10 20:01:47 -05:00
Venkatesh Pallipadi 8edc59d939 [CPUFREQ] Bug fix for acpi-cpufreq and cpufreq_stats oops on frequency change notification
Fixes the oops in cpufreq_stats with acpi_cpufreq driver.  The issue was
that the frequency was reported as 0 in acpi-cpufreq.c.  The bug is due to
different indicies for freq_table and ACPI perf table.

Also adds a check in cpufreq_stats to check for error return from
freq_table_get_index() and avoid using the error return value.

Patch fixes the issue reported at
http://www.ussg.iu.edu/hypermail/linux/kernel/0611.2/0629.html
and also other similar issue here
http://bugme.osdl.org/show_bug.cgi?id=7383 comment 53

Signed-off-by: Dhaval Giani <dhaval.giani@gmail.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2006-12-22 22:45:41 -05:00
Gautham R Shenoy e08f5f5bb5 [CPUFREQ] Fix coding style issues in cpufreq.
Clean up cpufreq subsystem to fix coding style issues and to improve
the readability.

Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2006-11-06 19:16:34 -05:00
Dave Jones ddad65df00 [CPUFREQ] Fix some more CPU hotplug locking.
Lukewarm IQ detected in hotplug locking
BUG: warning at kernel/cpu.c:38/lock_cpu_hotplug()
[<b0134a42>] lock_cpu_hotplug+0x42/0x65
[<b02f8af1>] cpufreq_update_policy+0x25/0xad
[<b0358756>] kprobe_flush_task+0x18/0x40
[<b0355aab>] schedule+0x63f/0x68b
[<b01377c2>] __link_module+0x0/0x1f
[<b0119e7d>] __cond_resched+0x16/0x34
[<b03560bf>] cond_resched+0x26/0x31
[<b0355b0e>] wait_for_completion+0x17/0xb1
[<f965c547>] cpufreq_stat_cpu_callback+0x13/0x20 [cpufreq_stats]
[<f9670074>] cpufreq_stats_init+0x74/0x8b [cpufreq_stats]
[<b0137872>] sys_init_module+0x91/0x174
[<b0102c81>] sysenter_past_esp+0x56/0x79

As there are other places that call cpufreq_update_policy without
the hotplug lock, it seems better to keep the hotplug locking
at the lower level for the time being until this is revamped.

Signed-off-by: Dave Jones <davej@redhat.com>
2006-09-22 19:15:23 -04:00
Jörn Engel 6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Chandra Seetharaman 65edc68c34 [PATCH] cpu hotplug: make [un]register_cpu_notifier init time only
CPUs come online only at init time (unless CONFIG_HOTPLUG_CPU is defined).
So, cpu_notifier functionality need to be available only at init time.

This patch makes register_cpu_notifier() available only at init time, unless
CONFIG_HOTPLUG_CPU is defined.

This patch exports register_cpu_notifier() and unregister_cpu_notifier() only
if CONFIG_HOTPLUG_CPU is defined.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:41 -07:00
Dave Jones 511e9ee170 [CPUFREQ] CodingStyle nits in cpufreq_stats.c
Signed-off-by: Dave Jones <davej@redhat.com>
2006-05-30 17:57:14 -04:00
Sam Ravnborg bb1a813d3c [PATCH] cpufreq: fix section mismatch warnings
cpufreq are the only remaining bit to be solved for me to have a modpost
clean build for sparc64 - so I took one more look at it.
changelog entry:

Fix section mismatch warnings in cpufreq:
WARNING: drivers/cpufreq/cpufreq_stats.o - Section mismatch: reference to .init.text: from .data between 'cpufreq_stat_cpu_notifier' (at offset 0xa8) and 'notifier_policy_block'
WARNING: drivers/cpufreq/cpufreq_stats.o - Section mismatch: reference to .init.text: from .exit.text after 'cleanup_module' (at offset 0x30)

The culprint is the function: cpufreq_stat_cpu_callback
It is marked __cpuinit which get's redefined to __init in case
HOTPLUG_CPU is not enabled as per. init.h:

#ifdef CONFIG_HOTPLUG_CPU
#define __cpuinit
#else
#define __cpuinit       __init
#endif

$> grep HOTPLUG .config
CONFIG_HOTPLUG=y

But cpufreq_stat_cpu_callback() is used in:
__exit cpufreq_stats_exit()
static struct notifier_block cpufreq_stat_cpu_notifier

cpufreq_stat_cpu_notifier is again used in:
__init cpufreq_stats_init()
__exit cpufreq_stats_exit()

So in both cases used from both __init and __exit context.
Only solution seems to drop __cpuinit tag.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2006-03-11 13:35:43 -05:00
Dave Jones 32ee8c3e47 [CPUFREQ] Lots of whitespace & CodingStyle cleanup.
Signed-off-by: Dave Jones <davej@redhat.com>
2006-02-28 00:43:23 -05:00
Linus Torvalds dad2ad82c5 Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq 2005-11-07 13:28:20 -08:00
Dave Jones b7fb358c7c [CPUFREQ] Fix up compile of cpufreq_stats
Whoops, I lost a hunk of the last patch somehow.

Signed-off-by: Dave Jones <davej@redhat.com>
2005-11-01 23:13:45 -08:00
Ashok Raj c32b6b8e52 [PATCH] create and destroy cpufreq sysfs entries based on cpu notifiers
cpufreq entries in sysfs should only be populated when CPU is online state.
 When we either boot with maxcpus=x and then boot the other cpus by echoing
to sysfs online file, these entries should be created and destroyed when
CPU_DEAD is notified.  Same treatement as cache entries under sysfs.

We place the processor in the lowest frequency, so hw managed P-State
transitions can still work on the other threads to save power.

Primary goal was to just make these directories appear/disapper dynamically.

There is one in this patch i had to do, which i really dont like myself but
probably best if someone handling the cpufreq infrastructure could give
this code right treatment if this is not acceptable.  I guess its probably
good for the first cut.

- Converting lock_cpu_hotplug()/unlock_cpu_hotplug() to disable/enable preempt.
  The locking was smack in the middle of the notification path, when the
  hotplug is already holding the lock. I tried another solution to avoid this
  so avoid taking locks if we know we are from notification path. The solution
  was getting very ugly and i decided this was probably good for this iteration
  until someone who understands cpufreq could do a better job than me.

(akpm: export cpucontrol to GPL modules: drivers/cpufreq/cpufreq_stats.c now
does lock_cpu_hotplug())

Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Zwane Mwaikambo <zwane@holomorphy.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:14 -08:00