Commit Graph

92 Commits

Author SHA1 Message Date
Ingo Molnar 5b3cc15aff sched/headers: Prepare to move the memalloc_noio_*() APIs to <linux/sched/mm.h>
Update the .c files that depend on these APIs.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:33 +01:00
Rafael J. Wysocki a9306a6363 PM / runtime: Avoid false-positive warnings from might_sleep_if()
The might_sleep_if() assertions in __pm_runtime_idle(),
__pm_runtime_suspend() and __pm_runtime_resume() may generate
false-positive warnings in some situations.  For example, that
happens if a nested pm_runtime_get_sync()/pm_runtime_put() pair
is executed with disabled interrupts within an outer
pm_runtime_get_sync()/pm_runtime_put() section for the same device.
[Generally, pm_runtime_get_sync() may sleep, so it should not be
called with disabled interrupts, but in this particular case the
previous pm_runtime_get_sync() guarantees that the device will not
be suspended, so the inner pm_runtime_get_sync() will return
immediately after incrementing the device's usage counter.]

That started to happen in the i915 driver in 4.10-rc, leading to
the following splat:

 BUG: sleeping function called from invalid context at drivers/base/power/runtime.c:1032
 in_atomic(): 1, irqs_disabled(): 0, pid: 1500, name: Xorg
 1 lock held by Xorg/1500:
  #0:  (&dev->struct_mutex){+.+.+.}, at:
  [<ffffffffa0680c13>] i915_mutex_lock_interruptible+0x43/0x140 [i915]
 CPU: 0 PID: 1500 Comm: Xorg Not tainted
 Call Trace:
  dump_stack+0x85/0xc2
  ___might_sleep+0x196/0x260
  __might_sleep+0x53/0xb0
  __pm_runtime_resume+0x7a/0x90
  intel_runtime_pm_get+0x25/0x90 [i915]
  aliasing_gtt_bind_vma+0xaa/0xf0 [i915]
  i915_vma_bind+0xaf/0x1e0 [i915]
  i915_gem_execbuffer_relocate_entry+0x513/0x6f0 [i915]
  i915_gem_execbuffer_relocate_vma.isra.34+0x188/0x250 [i915]
  ? trace_hardirqs_on+0xd/0x10
  ? i915_gem_execbuffer_reserve_vma.isra.31+0x152/0x1f0 [i915]
  ? i915_gem_execbuffer_reserve.isra.32+0x372/0x3a0 [i915]
  i915_gem_do_execbuffer.isra.38+0xa70/0x1a40 [i915]
  ? __might_fault+0x4e/0xb0
  i915_gem_execbuffer2+0xc5/0x260 [i915]
  ? __might_fault+0x4e/0xb0
  drm_ioctl+0x206/0x450 [drm]
  ? i915_gem_execbuffer+0x340/0x340 [i915]
  ? __fget+0x5/0x200
  do_vfs_ioctl+0x91/0x6f0
  ? __fget+0x111/0x200
  ? __fget+0x5/0x200
  SyS_ioctl+0x79/0x90
  entry_SYSCALL_64_fastpath+0x23/0xc6

even though the code triggering it is correct.

Unfortunately, the might_sleep_if() assertions in question are
too coarse-grained to cover such cases correctly, so make them
a bit less sensitive in order to avoid the false-positives.

Reported-and-tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-02-04 00:44:36 +01:00
Linus Torvalds 098c30557a Driver core patches for 4.10-rc1
Here's the new driver core patches for 4.10-rc1.
 
 Big thing here is the nice addition of "functional dependencies" to the
 driver core.  The idea has been talked about for a very long time, great
 job to Rafael for stepping up and implementing it. It's been tested for
 longer than the 4.9-rc1 date, we held off on merging it earlier in order
 to feel more comfortable about it.
 
 Other than that, it's just a handful of small other patches, some good
 cleanups to the mess that is the firmware class code, and we have a test
 driver for the deferred probe logic.
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here's the new driver core patches for 4.10-rc1.

  Big thing here is the nice addition of "functional dependencies" to
  the driver core. The idea has been talked about for a very long time,
  great job to Rafael for stepping up and implementing it. It's been
  tested for longer than the 4.9-rc1 date, we held off on merging it
  earlier in order to feel more comfortable about it.

  Other than that, it's just a handful of small other patches, some good
  cleanups to the mess that is the firmware class code, and we have a
  test driver for the deferred probe logic.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'driver-core-4.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (30 commits)
  firmware: Correct handling of fw_state_wait() return value
  driver core: Silence device links sphinx warning
  firmware: remove warning at documentation generation time
  drivers: base: dma-mapping: Fix typo in dmam_alloc_non_coherent comments
  driver core: test_async: fix up typo found by 0-day
  firmware: move fw_state_is_done() into UHM section
  firmware: do not use fw_lock for fw_state protection
  firmware: drop bit ops in favor of simple state machine
  firmware: refactor loading status
  firmware: fix usermode helper fallback loading
  driver core: firmware_class: convert to use class_groups
  driver core: devcoredump: convert to use class_groups
  driver core: class: add class_groups support
  kernfs: Declare two local data structures static
  driver-core: fix platform_no_drv_owner.cocci warnings
  drivers/base/memory.c: Remove unused 'first_page' variable
  driver core: add CLASS_ATTR_WO()
  drivers: base: cacheinfo: support DT overrides for cache properties
  drivers: base: cacheinfo: add pr_fmt logging
  drivers: base: cacheinfo: fix boot error message when acpi is enabled
  ...
2016-12-13 11:42:18 -08:00
Tony Lindgren bed570307e PM / wakeirq: Fix dedicated wakeirq for drivers not using autosuspend
I noticed some wakeirq flakeyness with consumer drivers not using
autosuspend. For drivers not using autosuspend, the wakeirq may never
get unmasked in rpm_suspend() because of irq desc->depth.

We are configuring dedicated wakeirqs to start with IRQ_NOAUTOEN as we
naturally don't want them running until rpm_suspend() is called.

However, when a consumer driver initially calls pm_runtime_get(), we
now wrongly start with disable_irq_nosync() call on the dedicated
wakeirq that is disabled to start with.

This causes desc->depth to toggle between 1 and 2 instead of the usual
0 and 1. This can prevent enable_irq() from unmasking the wakeirq as
that only happens at desc->depth 1.

This does not necessarily show up with drivers using autosuspend as
there is time for disable_irq_nosync() before rpm_suspend() gets called
after the autosuspend timeout.

Let's fix the issue by adding wirq->status that lazily gets set on
the first rpm_suspend(). We also need PM runtime core private functions
for dev_pm_enable_wake_irq_check() and dev_pm_disable_wake_irq_check()
so we can enable the dedicated wakeirq on the first rpm_suspend().

While at it, let's also fix the comments for dev_pm_enable_wake_irq()
and dev_pm_disable_wake_irq(). Those can still be used by the consumer
drivers as needed because the IRQ core manages the interrupt usecount
for us.

Fixes: 4990d4fe32 (PM / Wakeirq: Add automated device wake IRQ handling)
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-12-06 23:45:59 +01:00
Ulf Hansson 1d9174fbc5 PM / Runtime: Defer resuming of the device in pm_runtime_force_resume()
When the pm_runtime_force_suspend|resume() helpers were invented, we still
had CONFIG_PM_RUNTIME and CONFIG_PM_SLEEP as separate Kconfig options.

To make sure these helpers worked for all combinations and without
introducing too much of complexity, the device was always resumed in
pm_runtime_force_resume().

More precisely, when CONFIG_PM_SLEEP was set and CONFIG_PM_RUNTIME was
unset, we needed to resume the device as the subsystem/driver couldn't
rely on using runtime PM to do it.

As the CONFIG_PM_RUNTIME option was merged into CONFIG_PM a while ago, it
removed this combination, of using CONFIG_PM_SLEEP without the earlier
CONFIG_PM_RUNTIME.

For this reason we can now rely on the subsystem/driver to use runtime PM
to resume the device, instead of forcing that to be done in all cases. In
other words, let's defer the runtime resume to a later point when it's
actually needed.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-19 00:15:39 +01:00
Ulf Hansson a8636c8964 PM / Runtime: Don't allow to suspend a device with an active child
When resuming a device in __pm_runtime_set_status(), the prerequisite is
that its parent must already be active, else an error code is returned and
the device's status remains suspended.

When suspending a device there is no similar constraints being validated.
Let's change this to make the behaviour consistent, by not allowing to
suspend a device with an active child, unless it has been explicitly set to
ignore its children.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-09 15:49:37 +01:00
Rafael J. Wysocki baa8809f60 PM / runtime: Optimize the use of device links
If the device has no links to suppliers that should be used for
runtime PM (links with DEVICE_LINK_PM_RUNTIME set), there is no
reason to walk the list of suppliers for that device during
runtime suspend and resume.

Add a simple mechanism to detect that case and possibly avoid the
extra unnecessary overhead.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-31 11:42:51 -06:00
Rafael J. Wysocki 21d5c57b37 PM / runtime: Use device links
Modify the runtime PM framework to use device links to ensure that
supplier devices will not be suspended if any of their consumer
devices are active.

The idea is to reference count suppliers on the consumer's resume
and drop references to them on its suspend.  The information on
whether or not the supplier has been reference counted by the
consumer's (runtime) resume is stored in a new field (rpm_active)
in the link object for each link.

It may be necessary to clean up those references when the
supplier is unbinding and that's why the links whose status is
DEVICE_LINK_SUPPLIER_UNBIND are skipped by the runtime suspend
and resume code.

The above means that if the consumer device is probed in the
runtime-active state, the supplier has to be resumed and reference
counted by device_link_add() so the code works as expected on its
(runtime) suspend.  There is a new flag, DEVICE_LINK_RPM_ACTIVE,
to tell device_link_add() about that (in which case the caller
is responsible for making sure that the consumer really will
be runtime-active when runtime PM is enabled for it).

The other new link flag, DEVICE_LINK_PM_RUNTIME, tells the core
whether or not the link should be used for runtime PM at all.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-31 11:42:51 -06:00
Ulf Hansson 216ef0b6b8 PM / Runtime: Clarify comment in rpm_resume() when resuming the parent
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-10-21 15:42:11 +02:00
Ulf Hansson 62006c1702 PM / Runtime: Remove the exported function pm_children_suspended()
The exported function pm_children_suspended() has only one caller, which is
the runtime PM internal function, rpm_check_suspend_allowed().

Let's clean-up this code, by removing pm_children_suspended() altogether
and instead do the one-liner check directly in rpm_check_suspend_allowed().

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-10-21 15:42:10 +02:00
Paul E. McKenney 778935778c PM / runtime: Use _rcuidle for runtime suspend tracepoints
Further testing with false negatives suppressed by commit 293e2421fe
("rcu: Remove superfluous versions of rcu_read_lock_sched_held()")
identified a few more unprotected uses of RCU from the idle loop.
Because RCU actively ignores idle-loop code (for energy-efficiency
reasons, among other things), using RCU from the idle loop can result
in too-short grace periods, in turn resulting in arbitrary misbehavior.

The affected function is rpm_suspend().

The resulting lockdep-RCU splat is as follows:

------------------------------------------------------------------------

Warning from omap3

===============================
[ INFO: suspicious RCU usage. ]
4.6.0-rc5-next-20160426+ #1112 Not tainted
-------------------------------
include/trace/events/rpm.h:63 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

RCU used illegally from idle CPU!
rcu_scheduler_active = 1, debug_locks = 0
RCU used illegally from extended quiescent state!
1 lock held by swapper/0/0:
 #0:  (&(&dev->power.lock)->rlock){-.-...}, at: [<c052ee24>] __pm_runtime_suspend+0x54/0x84

stack backtrace:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1112
Hardware name: Generic OMAP36xx (Flattened Device Tree)
[<c0110308>] (unwind_backtrace) from [<c010c3a8>] (show_stack+0x10/0x14)
[<c010c3a8>] (show_stack) from [<c047fec8>] (dump_stack+0xb0/0xe4)
[<c047fec8>] (dump_stack) from [<c052d7b4>] (rpm_suspend+0x604/0x7e4)
[<c052d7b4>] (rpm_suspend) from [<c052ee34>] (__pm_runtime_suspend+0x64/0x84)
[<c052ee34>] (__pm_runtime_suspend) from [<c04bf3bc>] (omap2_gpio_prepare_for_idle+0x5c/0x70)
[<c04bf3bc>] (omap2_gpio_prepare_for_idle) from [<c01255e8>] (omap_sram_idle+0x140/0x244)
[<c01255e8>] (omap_sram_idle) from [<c0126b48>] (omap3_enter_idle_bm+0xfc/0x1ec)
[<c0126b48>] (omap3_enter_idle_bm) from [<c0601db8>] (cpuidle_enter_state+0x80/0x3d4)
[<c0601db8>] (cpuidle_enter_state) from [<c0183c74>] (cpu_startup_entry+0x198/0x3a0)
[<c0183c74>] (cpu_startup_entry) from [<c0b00c0c>] (start_kernel+0x354/0x3c8)
[<c0b00c0c>] (start_kernel) from [<8000807c>] (0x8000807c)

------------------------------------------------------------------------

Reported-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-16 02:59:58 +02:00
Paul E. McKenney d7737ce964 PM / runtime: Add _rcuidle suffix to allow rpm_idle() use from idle
This commit appends a few _rcuidle suffixes to fix the following
RCU-used-from-idle bug:

> ===============================
> [ INFO: suspicious RCU usage. ]
> 4.6.0-rc5-next-20160426+ #1116 Not tainted
> -------------------------------
> include/trace/events/rpm.h:95 suspicious rcu_dereference_check() usage!
>
> other info that might help us debug this:
>
>
> RCU used illegally from idle CPU!
> rcu_scheduler_active = 1, debug_locks = 0
> RCU used illegally from extended quiescent state!
> 1 lock held by swapper/0/0:
>  #0:  (&(&dev->power.lock)->rlock){-.-...}, at: [<c052cc2c>] __rpm_callback+0x58/0x60
>
> stack backtrace:
> CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1116
> Hardware name: Generic OMAP36xx (Flattened Device Tree)
> [<c0110290>] (unwind_backtrace) from [<c010c3a8>] (show_stack+0x10/0x14)
> [<c010c3a8>] (show_stack) from [<c047fd68>] (dump_stack+0xb0/0xe4)
> [<c047fd68>] (dump_stack) from [<c052d5d0>] (rpm_suspend+0x580/0x768)
> [<c052d5d0>] (rpm_suspend) from [<c052ec58>] (__pm_runtime_suspend+0x64/0x84)
> [<c052ec58>] (__pm_runtime_suspend) from [<c04bf25c>] (omap2_gpio_prepare_for_idle+0x5c/0x70)
> [<c04bf25c>] (omap2_gpio_prepare_for_idle) from [<c0125568>] (omap_sram_idle+0x140/0x244)
> [<c0125568>] (omap_sram_idle) from [<c01269dc>] (omap3_enter_idle_bm+0xfc/0x1ec)
> [<c01269dc>] (omap3_enter_idle_bm) from [<c0601bdc>] (cpuidle_enter_state+0x80/0x3d4)
> [<c0601bdc>] (cpuidle_enter_state) from [<c0183b08>] (cpu_startup_entry+0x198/0x3a0)
> [<c0183b08>] (cpu_startup_entry) from [<c0b00c0c>] (start_kernel+0x354/0x3c8)
> [<c0b00c0c>] (start_kernel) from [<8000807c>] (0x8000807c)

In the immortal words of Steven Rostedt, "*Whack* *Whack* *Whack*!!!"

Reported-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
WhACKED-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-31 03:00:59 +02:00
Paul E. McKenney d44c950e93 PM / runtime: Add _rcuidle suffix to allow rpm_resume() to be called from idle
This commit applies another _rcuidle suffix to fix an RCU use from
idle.

> ===============================
> [ INFO: suspicious RCU usage. ]
> 4.6.0-rc5-next-20160426+ #1122 Not tainted
> -------------------------------
> include/trace/events/rpm.h:69 suspicious rcu_dereference_check() usage!
>
> other info that might help us debug this:
>
>
> RCU used illegally from idle CPU!
> rcu_scheduler_active = 1, debug_locks = 0
> RCU used illegally from extended quiescent state!
> 1 lock held by swapper/0/0:
>  #0:  (&(&dev->power.lock)->rlock){-.-...}, at: [<c052e3dc>] __pm_runtime_resume+0x3c/0x64
>
> stack backtrace:
> CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1122
> Hardware name: Generic OMAP36xx (Flattened Device Tree)
> [<c0110290>] (unwind_backtrace) from [<c010c3a8>] (show_stack+0x10/0x14)
> [<c010c3a8>] (show_stack) from [<c047fd68>] (dump_stack+0xb0/0xe4)
> [<c047fd68>] (dump_stack) from [<c052e178>] (rpm_resume+0x5cc/0x7f4)
> [<c052e178>] (rpm_resume) from [<c052e3ec>] (__pm_runtime_resume+0x4c/0x64)
> [<c052e3ec>] (__pm_runtime_resume) from [<c04bf2c4>] (omap2_gpio_resume_after_idle+0x54/0x68)
> [<c04bf2c4>] (omap2_gpio_resume_after_idle) from [<c01269dc>] (omap3_enter_idle_bm+0xfc/0x1ec)
> [<c01269dc>] (omap3_enter_idle_bm) from [<c060198c>] (cpuidle_enter_state+0x80/0x3d4)
> [<c060198c>] (cpuidle_enter_state) from [<c0183b08>] (cpu_startup_entry+0x198/0x3a0)
> [<c0183b08>] (cpu_startup_entry) from [<c0b00c0c>] (start_kernel+0x354/0x3c8)
> [<c0b00c0c>] (start_kernel) from [<8000807c>] (0x8000807c)

Reported-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-31 02:59:20 +02:00
Rafael J. Wysocki fa70db3f19 Merge branches 'pm-core', 'pm-clk', 'pm-domains' and 'pm-pci'
* pm-core:
  PM / runtime: Asynchronous "idle" in pm_runtime_allow()
  PM / runtime: print error when activating a child to unactive parent

* pm-clk:
  PM / clk: Add support for adding a specific clock from device-tree
  PM / clk: export symbols for existing pm_clk_<...> API fcns

* pm-domains:
  PM / Domains: Convert pm_genpd_init() to return an error code
  PM / Domains: Stop/start devices during system PM suspend/resume in genpd
  PM / Domains: Allow runtime PM during system PM phases
  PM / Runtime: Avoid resuming devices again in pm_runtime_force_resume()
  PM / Domains: Remove redundant pm_request_idle() call in genpd
  PM / Domains: Remove redundant wrapper functions for system PM
  PM / Domains: Allow genpd to power on during system PM phases

* pm-pci:
  PCI / PM: check all fields in pci_set_platform_pm()
2016-07-25 13:45:27 +02:00
Rafael J. Wysocki fe7450b05f PM / runtime: Asynchronous "idle" in pm_runtime_allow()
Arjan reports that it takes a relatively long time to enable runtime
PM for multiple devices at system startup, because all writes to the
"control" attribute in sysfs are handled synchronously and if the
device is suspended as a result of the write, it will block until
that operation is complete.

That may be avoided by passing the RPM_ASYNC flag to rpm_idle()
in pm_runtime_allow() which will make it execute the device's
"idle" callback asynchronously, so writes to "control" changing
it from "on" to "auto" will return without waiting.

Reported-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
2016-07-02 01:50:39 +02:00
Linus Walleij 71723f9546 PM / runtime: print error when activating a child to unactive parent
The code currently silently bails out with -EBUSY if you try to
activate a child to an inactive parent.

This typically happens when you have a runtime suspended parent
and runtime resume your child, but forgot to set .ignore_children
on the parent to true with pm_suspend_ignore_children(dev).

Silently ignoring this error is not good as it gives rise to
other strange behaviour like double-resume of devices after
silently bailing out of the .runtime_resume() callback.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-28 00:40:30 +02:00
Ulf Hansson 9f5b52747d PM / Runtime: Avoid resuming devices again in pm_runtime_force_resume()
If the runtime PM status of the device isn't RPM_SUSPENDED, prevent the
pm_runtime_force_resume() from invoking the ->runtime_resume() callback
for the device, as it's not the expected behaviour from the subsystem/driver.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-16 15:14:36 +02:00
Ulf Hansson 0ae3aeefab PM / Runtime: Fix error path in pm_runtime_force_resume()
As pm_runtime_set_active() may fail because the device's parent isn't
active, we can end up executing the ->runtime_resume() callback for the
device when it isn't allowed.

Fix this by invoking pm_runtime_set_active() before running the callback
and let's also deal with the error code.

Fixes: 37f204164d (PM: Add pm_runtime_suspend|resume_force functions)
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: 3.15+ <stable@vger.kernel.org> # 3.15+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-04-21 19:31:11 +02:00
Rafael J. Wysocki a436b6a19f PM / runtime: Add new helper for conditional usage count incrementation
Introduce a new runtime PM function, pm_runtime_get_if_in_use(),
that will increment the device's runtime PM usage counter and
return 1 if its status is RPM_ACTIVE and its usage counter
is greater than 0 at the same time (0 will be returned otherwise).

This is useful for things that should only be done if the device
is active (from the runtime PM perspective) and used by somebody
(as indicated by the usage counter) already and they are not worth
bothering otherwise.

Requested-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-21 03:11:12 +01:00
Ulf Hansson 5de85b9d57 PM / runtime: Re-init runtime PM states at probe error and driver unbind
There are two common expectations among several subsystems/drivers that
deploys runtime PM support, but which isn't met by the driver core.

Expectation 1)
At ->probe() the subsystem/driver expects the runtime PM status of the
device to be RPM_SUSPENDED, which is the initial status being assigned at
device registration.

This expectation is especially common among some of those subsystems/
drivers that manages devices with an attached PM domain, as those requires
the ->runtime_resume() callback at the PM domain level to be invoked
during ->probe().

Moreover these subsystems/drivers entirely relies on runtime PM resources
being managed at the PM domain level, thus don't implement their own set
of runtime PM callbacks.

These are two scenarios that suffers from this unmet expectation.

i) A failed ->probe() sequence requests probe deferral:

->probe()
  ...
  pm_runtime_enable()
  pm_runtime_get_sync()
  ...

err:
  pm_runtime_put()
  pm_runtime_disable()
  ...

As there are no guarantees that such sequence turns the runtime PM status
of the device into RPM_SUSPENDED, the re-trying ->probe() may start with
the status in RPM_ACTIVE.

In such case the runtime PM core won't invoke the ->runtime_resume()
callback because of a pm_runtime_get_sync(), as it considers the device to
be already runtime resumed.

ii) A driver re-bind sequence:

At driver unbind, the subsystem/driver's >remove() callback invokes a
sequence of runtime PM APIs, to undo actions during ->probe() and to put
the device into low power state.

->remove()
  ...
  pm_runtime_put()
  pm_runtime_disable()
  ...

Similar as in the failing ->probe() case, this sequence don't guarantee
the runtime PM status of the device to turn into RPM_SUSPENDED.

Trying to re-bind the driver thus causes the same issue as when re-trying
->probe(), in the probe deferral scenario.

Expectation 2)
Drivers that invokes the pm_runtime_irq_safe() API during ->probe(),
triggers the runtime PM core to increase the usage count for the device's
parent and permanently make it runtime resumed.

The usage count is only dropped at device removal, which also allows it to
be runtime suspended again.

A re-trying ->probe() repeats the call to pm_runtime_irq_safe() and thus
once more triggers the usage count of the device's parent to be increased.

This leads to not only an imbalance issue of the usage count of the
device's parent, but also to keep it runtime resumed permanently even if
->probe() fails.

To address these issues, let's change the policy of the driver core to
meet these expectations. More precisely, at ->probe() failures and driver
unbind, restore the initial states of runtime PM.

Although to still allow subsystem's to control PM for devices that doesn't
->probe() successfully, don't restore the initial states unless runtime PM
is disabled.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-11-30 14:50:05 +01:00
Tony Lindgren 4990d4fe32 PM / Wakeirq: Add automated device wake IRQ handling
Turns out we can automate the handling for the device_may_wakeup()
quite a bit by using the kernel wakeup source list as suggested
by Rafael J. Wysocki <rjw@rjwysocki.net>.

And as some hardware has separate dedicated wake-up interrupt
in addition to the IO interrupt, we can automate the handling by
adding a generic threaded interrupt handler that just calls the
device PM runtime to wake up the device.

This allows dropping code from device drivers as we currently
are doing it in multiple ways, and often wrong.

For most drivers, we should be able to drop the following
boilerplate code from runtime_suspend and runtime_resume
functions:

	...
	device_init_wakeup(dev, true);
	...
	if (device_may_wakeup(dev))
		enable_irq_wake(irq);
	...
	if (device_may_wakeup(dev))
		disable_irq_wake(irq);
	...
	device_init_wakeup(dev, false);
	...

We can replace it with just the following init and exit
time code:

	...
	device_init_wakeup(dev, true);
	dev_pm_set_wake_irq(dev, irq);
	...
	dev_pm_clear_wake_irq(dev);
	device_init_wakeup(dev, false);
	...

And for hardware with dedicated wake-up interrupts:

	...
	device_init_wakeup(dev, true);
	dev_pm_set_dedicated_wake_irq(dev, irq);
	...
	dev_pm_clear_wake_irq(dev);
	device_init_wakeup(dev, false);
	...

Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-20 01:56:31 +02:00
Tony Lindgren 56f487c780 PM / Runtime: Update last_busy in rpm_resume
If we don't update last_busy in rpm_resume, devices can go back
to sleep immediately after resume. This happens at least in
cases where the device has been powered off and does not have
any interrupt pending until there's something in the FIFO.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-20 01:55:02 +02:00
Rafael J. Wysocki d30d819dc8 PM: Drop CONFIG_PM_RUNTIME from the driver core
After commit b2b49ccbdd (PM: Kconfig: Set PM_RUNTIME if PM_SLEEP is
selected) PM_RUNTIME is always set if PM is set, so quite a few
depend on CONFIG_PM or even may be dropped entirely in some cases.

Replace CONFIG_PM_RUNTIME with CONFIG_PM in the PM core code.

Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-12-04 00:46:58 +01:00
Andrzej Hajda dbcd2d7253 PM / Runtime: Rework RPM get callback routines
PM uses three separate functions to fetch RPM callbacks.
These functions uses quite complicated macro in their body.
The patch replaces these routines with one small macro and
one helper function.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-06 00:49:57 +01:00
Rafael J. Wysocki 36cc86e8ec Merge branches 'pm-runtime' and 'pm-sleep'
* pm-runtime:
  PM / Runtime: Update runtime_idle() documentation for return value meaning

* pm-sleep:
  PM / sleep: Correct whitespace errors in <linux/pm.h>
  PM: Add missing "freeze" state
  PM / Hibernate: Spelling s/anonymouns/anonymous/
  PM / Runtime: Add missing "it" in comment
  PM / suspend: Remove unnecessary !!
  PCI / PM: Resume runtime-suspended devices later during system suspend
  ACPI / PM: Resume runtime-suspended devices later during system suspend
  PM / sleep: Set pm_generic functions to NULL for !CONFIG_PM_SLEEP
  PM: fix typo in comment
  PM / hibernate: use name_to_dev_t to parse resume
  PM / wakeup: Include appropriate header file in kernel/power/wakelock.c
  PM / sleep: Move prototype declaration to header file kernel/power/power.h
  PM / sleep: Asynchronous threads for suspend_late
  PM / sleep: Asynchronous threads for suspend_noirq
  PM / sleep: Asynchronous threads for resume_early
  PM / sleep: Asynchronous threads for resume_noirq
  PM / sleep: Two flags for async suspend_noirq and suspend_late
2014-03-20 13:25:54 +01:00
Geert Uytterhoeven 7b60894ff8 PM / Runtime: Add missing "it" in comment
Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-12 00:54:53 +01:00
Ulf Hansson 37f204164d PM: Add pm_runtime_suspend|resume_force functions
This patch provides two new runtime PM helper functions which intend to
be used from system suspend/resume callbacks, to make sure devices are
put into low power state during system suspend and brought back to full
power at system resume.

The prerequisite is to have all levels of a device's runtime PM
callbacks to be defined through the SET_PM_RUNTIME_PM_OPS macro, which
means these are available for CONFIG_PM.

By using the new runtime PM helper functions especially the two
scenarios below will be addressed.

1) The PM core prevents .runtime_suspend callbacks from being invoked
during system suspend. That means even for a runtime PM centric
subsystem and driver, the device needs to be put into low power state
from a system suspend callback. Otherwise it may very well be left in
full power state (runtime resumed) while the system is suspended. By
using the new helper functions, we make sure to walk the hierarchy of
a device's power domain, subsystem and driver.

2) Subsystems and drivers need to cope with all the combinations of
CONFIG_PM_SLEEP and CONFIG_PM_RUNTIME. The two new helper functions
smothly addresses this.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-02 00:18:15 +01:00
Ulf Hansson 5f59df7983 PM / runtime: Fetch runtime PM callbacks using a macro
While fetching the proper runtime PM callback, we walk the hierarchy of
device's power domains, subsystems and drivers.

This is common for rpm_suspend(), rpm_idle() and rpm_resume(). Let's
clean up the code by using a macro that handles this.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-02 00:18:15 +01:00
Ulf Hansson d66e6db28d PM / Runtime: Respect autosuspend when idle triggers suspend
For devices which don't have a .runtime_idle() callback or if it
returns 0, rpm_idle() will end up in triggering a call to
rpm_suspend(), thus trying to carry out a runtime suspend directly
from runtime_idle().

In the above situation we want to respect devices which has enabled
autosuspend, we therfore append the flag sent to rpm_suspend with
RPM_AUTO.

Do note that drivers still needs to update the device last busy mark,
to control the delay for this circumstance.

Updated runtime PM documentation accordingly.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-16 02:06:57 +02:00
Rafael J. Wysocki 45f0a85c82 PM / Runtime: Rework the "runtime idle" helper routine
The "runtime idle" helper routine, rpm_idle(), currently ignores
return values from .runtime_idle() callbacks executed by it.
However, it turns out that many subsystems use
pm_generic_runtime_idle() which checks the return value of the
driver's callback and executes pm_runtime_suspend() for the device
unless that value is not 0.  If that logic is moved to rpm_idle()
instead, pm_generic_runtime_idle() can be dropped and its users
will not need any .runtime_idle() callbacks any more.

Moreover, the PCI, SCSI, and SATA subsystems' .runtime_idle()
routines, pci_pm_runtime_idle(), scsi_runtime_idle(), and
ata_port_runtime_idle(), respectively, as well as a few drivers'
ones may be simplified if rpm_idle() calls rpm_suspend() after 0 has
been returned by the .runtime_idle() callback executed by it.

To reduce overall code bloat, make the changes described above.

Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Kevin Hilman <khilman@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
2013-06-03 21:49:52 +02:00
Ulf Hansson db28dfac99 PM / Runtime: Asyncronous idle|suspend parent devices at removal
For irq safe devices return the runtime reference for the parent
by using the asyncronous runtime PM API. Thus we don't have to
wait for it to become idle|suspended. Instead we can move on and
handle the next device in queue.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-12 13:34:57 +02:00
Ming Lei db88175f41 pm / runtime: force memory allocation with no I/O during Runtime PM callbcack
Apply the introduced memalloc_noio_save() and memalloc_noio_restore() to
force memory allocation with no I/O during runtime_resume/runtime_suspend
callback on device with the flag of 'memalloc_noio' set.

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David Decotigny <david.decotigny@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oneukum@suse.de>
Cc: Jiri Kosina <jiri.kosina@suse.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-23 17:50:16 -08:00
Ming Lei e823407f7b pm / runtime: introduce pm_runtime_set_memalloc_noio()
Introduce the flag memalloc_noio in 'struct dev_pm_info' to help PM core
to teach mm not allocating memory with GFP_KERNEL flag for avoiding
probable deadlock.

As explained in the comment, any GFP_KERNEL allocation inside
runtime_resume() or runtime_suspend() on any one of device in the path
from one block or network device to the root device in the device tree
may cause deadlock, the introduced pm_runtime_set_memalloc_noio() sets
or clears the flag on device in the path recursively.

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oneukum@suse.de>
Cc: Jiri Kosina <jiri.kosina@suse.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Greg KH <greg@kroah.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David Decotigny <david.decotigny@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-23 17:50:16 -08:00
Kevin Hilman 6f3c77b040 PM / Runtime: let rpm_resume() succeed if RPM_ACTIVE, even when disabled, v2
There are several drivers where the return value of
pm_runtime_get_sync() is used to decide whether or not it is safe to
access hardware and that don't provide .suspend() callbacks for system
suspend (but may use late/noirq callbacks.)  If such a driver happens
to call pm_runtime_get_sync() during system suspend, after the core
has disabled runtime PM, it will get the error code and will decide
that the hardware should not be accessed, although this may be a wrong
conclusion, depending on the state of the device when runtime PM was
disabled.

Drivers might work around this problem by using a test like:

   ret = pm_runtime_get_sync(dev);
   if (!ret || (ret == -EACCES && driver_private_data(dev)->suspended)) {
      /* access hardware */
   }

where driver_private_data(dev)->suspended is a flag set by the
driver's .suspend() method (that would have to be added for this
purpose).  However, that potentially would need to be done by multiple
drivers which means quite a lot of duplicated code and bloat.

To avoid that we can use the observation that the core sets
dev->power.is_suspended before disabling runtime PM and use that
instead of the driver's private flag.  Still, potentially many drivers
would need to repeat that same check in quite a few places, so it's
better to let the core do it.

Then we can be a bit smarter and check whether or not runtime PM was
disabled by the core only (disable_depth == 1) or by someone else in
addition to the core (disable_depth > 1).  In the former case
rpm_resume() can return 1 if the runtime PM status is RPM_ACTIVE,
because it means the device was active when the core disabled runtime
PM.  In the latter case it should still return -EACCES, because it
isn't clear why runtime PM has been disabled.

Tested on AM3730/Beagle-xM where a wakeup IRQ firing during the late
suspend phase triggers runtime PM activity in the I2C driver since the
wakeup IRQ is on an I2C-connected PMIC.

[rjw: Modified whitespace to follow the file's convention.]

Signed-off-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-09-22 21:15:08 +02:00
Rafael J. Wysocki 55d7ec4520 PM / Runtime: Check device PM QoS setting before "no callbacks" check
If __dev_pm_qos_read_value(dev) returns a negative value,
rpm_suspend() should return -EPERM for dev even if its
power.no_callbacks flag is set.  For this to happen, the device's
power.no_callbacks flag has to be checked after the PM QoS check,
so move the PM QoS check to rpm_check_suspend_allowed() (this will
make it cover idle notifications as well as runtime suspend too).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable@vger.kernel.org
2012-08-17 19:36:36 +02:00
Rafael J. Wysocki 58a34de7b1 PM / Runtime: Clear power.deferred_resume on success in rpm_suspend()
The power.deferred_resume can only be set if the runtime PM status
of device is RPM_SUSPENDING and it should be cleared after its
status has been changed, regardless of whether or not the runtime
suspend has been successful.  However, it only is cleared on
suspend failure, while it may remain set on successful suspend and
is happily leaked to rpm_resume() executed in that case.

That shouldn't happen, so if power.deferred_resume is set in
rpm_suspend() after the status has been changed to RPM_SUSPENDED,
clear it before calling rpm_resume().  Then, it doesn't need to be
cleared before changing the status to RPM_SUSPENDING any more,
because it's always cleared after the status has been changed to
either RPM_SUSPENDED (on success) or RPM_ACTIVE (on failure).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable@vger.kernel.org
2012-08-17 19:36:36 +02:00
Rafael J. Wysocki 7f321c26c0 PM / Runtime: Fix rpm_resume() return value for power.no_callbacks set
For devices whose power.no_callbacks flag is set, rpm_resume()
should return 1 if the device's parent is already active, so that
the callers of pm_runtime_get() don't think that they have to wait
for the device to resume (asynchronously) in that case (the core
won't queue up an asynchronous resume in that case, so there's
nothing to wait for anyway).

Modify the code accordingly (and make sure that an idle notification
will be queued up on success, even if 1 is to be returned).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable@vger.kernel.org
2012-08-17 19:36:35 +02:00
Rafael J. Wysocki 76e267d822 PM / Runtime: Remove device fields related to suspend time, v2
After the previous changes in default_stop_ok() and
default_power_down_ok() for PM domains, there are two fields in
struct dev_pm_info that aren't necessary any more,  suspend_time
and max_time_suspended_ns.

Remove those fields along with all of the code that accesses them,
which simplifies the runtime PM framework quite a bit.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-05-01 21:28:38 +02:00
Alan Stern f2791d733a PM / Runtime: don't forget to wake up waitqueue on failure
This patch (as1535) fixes a bug in the runtime PM core.  When a
runtime suspend attempt completes, whether successfully or not, the
device's power.wait_queue is supposed to be signalled.  But this
doesn't happen in the failure pathway of rpm_suspend() when another
autosuspend attempt is rescheduled.  As a result, a task can get stuck
indefinitely on the wait queue (I have seen this happen in testing).

The patch fixes the problem by moving the wake_up_all() call up near
the start of the failure code.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-03-26 22:46:52 +02:00
Rafael J. Wysocki 0015afaa1f Merge branch 'pm-runtime' into pm-for-linus
* pm-runtime:
  PM / Runtime: Use device PM QoS constraints (v2)
2011-12-25 23:43:05 +01:00
Rafael J. Wysocki 35cd133c61 PM: Run the driver callback directly if the subsystem one is not there
Make the PM core execute driver PM callbacks directly if the
corresponding subsystem callbacks are not present.

There are three reasons for doing that.  First, it reflects the
behavior of drivers/base/dd.c:really_probe() that runs the driver's
.probe() callback directly if the bus type's one is not defined, so
this change will remove one arbitrary difference between the PM core
and the remaining parts of the driver core.  Second, it will allow
some subsystems, whose PM callbacks don't do anything except for
executing driver callbacks, to be simplified quite a bit by removing
those "forward-only" callbacks.  Finally, it will allow us to remove
one level of indirection in the system suspend and resume code paths
where it is not necessary, which is going to lead to less debug noise
with initcall_debug passed in the kernel command line (messages won't
be printed for driverless devices whose subsystems don't provide
PM callbacks among other things).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-12-21 22:01:05 +01:00
Rafael J. Wysocki 00dc9ad18d PM / Runtime: Use device PM QoS constraints (v2)
Make the runtime PM core use device PM QoS constraints to check if
it is allowed to suspend a given device, so that an error code is
returned if the device's own PM QoS constraint is negative or one of
its children has already been suspended for too long.  If this is
not the case, the maximum estimated time the device is allowed to be
suspended, computed as the minimum of the device's PM QoS constraint
and the PM QoS constraints of its children (reduced by the difference
between the current time and their suspend times) is stored in a new
device's PM field power.max_time_suspended_ns that can be used by
the device's subsystem or PM domain to decide whether or not to put
the device into lower-power (and presumably higher-latency) states
later (if the constraint is 0, which means "no constraint", the
power.max_time_suspended_ns is set to -1).

Additionally, the time of execution of the subsystem-level
.runtime_suspend() callback for the device is recorded in the new
power.suspend_time field for later use by the device's subsystem or
PM domain along with power.max_time_suspended_ns (it also is used
by the core code when the device's parent is suspended).

Introduce a new helper function,
pm_runtime_update_max_time_suspended(), allowing subsystems and PM
domains (or device drivers) to update the power.max_time_suspended_ns
field, for example after changing the power state of a suspended
device.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-12-01 21:46:42 +01:00
Linus Torvalds 32aaeffbd4 Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux
* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits)
  Revert "tracing: Include module.h in define_trace.h"
  irq: don't put module.h into irq.h for tracking irqgen modules.
  bluetooth: macroize two small inlines to avoid module.h
  ip_vs.h: fix implicit use of module_get/module_put from module.h
  nf_conntrack.h: fix up fallout from implicit moduleparam.h presence
  include: replace linux/module.h with "struct module" wherever possible
  include: convert various register fcns to macros to avoid include chaining
  crypto.h: remove unused crypto_tfm_alg_modname() inline
  uwb.h: fix implicit use of asm/page.h for PAGE_SIZE
  pm_runtime.h: explicitly requires notifier.h
  linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h
  miscdevice.h: fix up implicit use of lists and types
  stop_machine.h: fix implicit use of smp.h for smp_processor_id
  of: fix implicit use of errno.h in include/linux/of.h
  of_platform.h: delete needless include <linux/module.h>
  acpi: remove module.h include from platform/aclinux.h
  miscdevice.h: delete unnecessary inclusion of module.h
  device_cgroup.h: delete needless include <linux/module.h>
  net: sch_generic remove redundant use of <linux/module.h>
  net: inet_timewait_sock doesnt need <linux/module.h>
  ...

Fix up trivial conflicts (other header files, and  removal of the ab3550 mfd driver) in
 - drivers/media/dvb/frontends/dibx000_common.c
 - drivers/media/video/{mt9m111.c,ov6650.c}
 - drivers/mfd/ab3550-core.c
 - include/linux/dmaengine.h
2011-11-06 19:44:47 -08:00
Alan Stern 886486b792 PM / Runtime: Automatically retry failed autosuspends
Originally, the runtime PM core would send an idle notification
whenever a suspend attempt failed.  The idle callback routine could
then schedule a delayed suspend for some time later.

However this behavior was changed by commit
f71648d73c (PM / Runtime: Remove idle
notification after failing suspend).  No notifications were sent, and
there was no clear mechanism to retry failed suspends.

This caused problems for the usbhid driver, because it fails
autosuspend attempts as long as a key is being held down.  Therefore
this patch (as1492) adds a mechanism for retrying failed
autosuspends.  If the callback routine updates the last_busy field so
that the next autosuspend expiration time is in the future, the
autosuspend will automatically be rescheduled.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Henrik Rydberg <rydberg@euromail.se>
Cc: <stable@kernel.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-11-04 22:28:14 +01:00
venu byravarasu def0c0a37d PM / Runtime: Fix runtime accounting calculation error
With delta type being int, its value is made zero
for all values of now > 0x80000000.
Hence fixing it.

Signed-off-by: venu byravarasu <vbyravarasu@nvidia.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-11-04 22:28:10 +01:00
Paul Gortmaker 1b6bc32f0a drivers/base: Add export.h for EXPORT_SYMBOL/THIS_MODULE as required.
Most of these files were implicitly getting EXPORT_SYMBOL via
device.h which was including module.h, but that path will be broken
soon.

[ with input from Stephen Rothwell <sfr@canb.auug.org.au> ]

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:31:38 -04:00
Ming Lei 857b36c7b0 PM / Runtime: Handle .runtime_suspend() failure correctly
If .runtime_suspend() returns -EAGAIN or -EBUSY, the device should
still be in ACTIVE state, so it is not necessary to send an idle
notification to its parent.  If .runtime_suspend() returns other
fatal failure, it doesn't make sense to send idle notification to
its parent.

Skip parent idle notification when failure is returned from
.runtime_suspend() and update comments in rpm_suspend() to reflect
that change.

[rjw: Modified the subject and changelog slightly.]

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-16 23:25:23 +02:00
Ming Lei 47d8f0bac0 PM / Runtime: Fix kerneldoc comment for rpm_suspend()
This patch fix kerneldoc comments for rpm_suspend():

 - 'Cancel a pending idle notification' should be put before, also
   should be changed to 'Cancel a pending idle notification,
   autosuspend or suspend'.

 - idle notification for the device after succeeding suspend has
   been removed, so update the comment accordingly.

[rjw: Modified the subject and changelog slightly.]

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-16 23:25:08 +02:00
Ming Lei c3dc2f1462 PM / Runtime: Replace dev_dbg() with trace_rpm_*()
This patch replaces dev_dbg with trace_rpm_* inside
the three important functions:

	rpm_idle
	rpm_suspend
	rpm_resume

Trace points have the below advantages compared with dev_dbg:

	- trace points include much runtime information(such as
	running cpu, current task, ...)

	- most of linux distributions may disable "verbose debug"
	driver debug compile switch, so it is very difficult to
	report/debug runtime pm related problems from distribution
	users without this kind of debug information.

	- for upstream kernel users, enableing the debug switch will
	produce many useless "rpm_resume" output, and it is very noise.

	- dev_dbg inside rpm_suspend/rpm_resume may have some effects
	on runtime pm behaviour of console devicer

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-09-27 22:54:41 +02:00
Rafael J. Wysocki ad3c36a534 PM / Runtime: Don't run callbacks under lock for power.irq_safe set
The rpm_suspend() and rpm_resume() routines execute subsystem or PM
domain callbacks under power.lock if power.irq_safe is set for the
given device.  This is inconsistent with that rpm_idle() does after
commit 02b2677 (PM / Runtime: Allow _put_sync() from
interrupts-disabled context) and is problematic for subsystems and PM
domains wanting to use power.lock for synchronization in their
runtime PM callbacks.

This change requires the code checking if the device's runtime PM
status is RPM_SUSPENDING or RPM_RESUMING to be modified too, to take
the power.irq_safe set case into account (that code wasn't reachable
before with power.irq_safe set, because it's executed with the
device's power.lock held).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-09-27 21:54:52 +02:00