Commit graph

47,892 commits

Author SHA1 Message Date
Mark Brown
1dfb6efd87 ASoC: Remove rbtree register cache
All users now use regmap directly so delete the ASoC version of the code.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-12-13 00:20:28 +08:00
Mark Brown
68556ca1e0 Merge branch 'mfd/wm8994' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/misc into for-3.3 2011-12-13 00:19:20 +08:00
Mark Brown
8ab3069182 mfd: Convert wm8994 to use generic regmap irq_chip
Factor out the irq_chip implementation, substantially reducing the code
size for the driver.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>
2011-12-13 00:14:06 +08:00
Mark Brown
e292b578c9 Merge branch 'topic/irq' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap into wm8994-mfd 2011-12-13 00:12:48 +08:00
Mark Brown
7ed5849c28 mfd: Mark WM1811 GPIO6 register volatile for later revisions
For later chip revisions the WM1811 GPIO6 register is always volatile so
store the device revision when initialising the driver and then check at
runtime if we're running on a newer device.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>
2011-12-13 00:11:49 +08:00
Mark Brown
19f9557174 mfd: Add missing mutex.h inclusion to WM8994 core.h
struct wm8994 includes a mutex so we need to include mutex.h before we
declare it. All current users rely on this being done implicitly.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>
2011-12-13 00:11:43 +08:00
Mark Brown
43913e5ef9 mfd: Constify WM8994 regulator_init_data
The driver has no need to modify the regulator_init_data so declare it
const to allow machine code to do so.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>
2011-12-13 00:11:19 +08:00
Mark Brown
c3f1386171 mfd: Enable register cache for wm8994 devices
As part of this we provide information about the registers that exist in
the device to the regmap core, drop the small amount of cache that the
core had been using and let regmap do the sync.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>
2011-12-13 00:11:05 +08:00
Mark Brown
4412823a0a Merge branch 'topic/cache' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap into HEAD 2011-12-13 00:10:45 +08:00
Mark Brown
4de45284d3 mfd: Define some additional wm8994 registers
Add a bunch of definitions for wm8994 registers that are not currently
used by software.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>
2011-12-13 00:10:06 +08:00
Mark Brown
26c34c25e5 mfd: Disable more pulls on WM8994
Disable more pulls by default on WM8994 for a small current saving. Since
some designs do leave SPKMODE floating provide platform data to allow that
to be left enabled.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>
2011-12-13 00:09:34 +08:00
Joerg Roedel
2d5503b624 iommu/amd: Add routines to bind/unbind a pasid
This patch adds routines to bind a specific process
address-space to a given PASID.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2011-12-12 15:34:42 +01:00
Joerg Roedel
ed96f228ba iommu/amd: Implement device aquisition code for IOMMUv2
This patch adds the amd_iommu_init_device() and
amd_iommu_free_device() functions which make a device and
the IOMMU ready for IOMMUv2 usage.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2011-12-12 15:32:51 +01:00
Joerg Roedel
6a113ddc03 iommu/amd: Add device errata handling
Add infrastructure for errata-handling and handle two known
erratas in the IOMMUv2 code.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2011-12-12 15:19:06 +01:00
David Howells
267aed9dfe UAPI: elf_read_implies_exec() is a kernel-only feature - so hide from userspace
elf_read_implies_exec() is a kernel-only feature as the second parameter is a
constant that isn't exported to userspace.  Not only that, but the
arch-specific overrides are not exported either.

So hide the macro from userspace.

Similarly, struct file should not be predeclared in userspace.

Signed-off-by: David Howells <dhowells@redhat.com>
2011-12-12 13:54:36 +00:00
Michal Nazarewicz
7177aed44f usb: gadget: rename usb_gadget_driver::speed to max_speed
This commit renames the “speed” field of the usb_gadget_driver
structure to “max_speed”.  This is so that to make it more
apparent that the field represents the maximum speed gadget
driver can support.

This also make the field look more like fields with the same
name in usb_gadget and usb_composite_driver structures.  All
of those represent the *maximal* speed given entity supports.

After this commit, there are the following fields in various
structures:
* usb_gadget::speed - the current connection speed,
* usb_gadget::max_speed - maximal speed UDC supports,
* usb_gadget_driver::max_speed - maximal speed gadget driver
  supports, and
* usb_composite_driver::max_speed - maximal speed composite
  gadget supports.

Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2011-12-12 11:45:12 +02:00
Michal Nazarewicz
d327ab5b6d usb: gadget: replace usb_gadget::is_dualspeed with max_speed
This commit replaces usb_gadget's is_dualspeed field with
a max_speed field.

[ balbi@ti.com : Fixed DWC3 driver ]

Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2011-12-12 11:45:11 +02:00
Kuninori Morimoto
f1ee56a000 usb: gadget: renesas_usbhs: add platform power control function
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2011-12-12 11:44:58 +02:00
Kuninori Morimoto
a49a88f108 usb: gadget: renesas_usbhs: tidyup the unit of detection_delay
detection_delay was assumed as msec

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2011-12-12 11:44:57 +02:00
Courtney Cavin
ff803ed4dd Input: add driver for Sharp gp2ap002a00f proximity sensor
This driver adds support for Sharp's GP2AP002A00F proximity sensor. The
proximity is measured as a binary switch, i.e. an object is either
detected or not detected. Hence, this driver is implemented as a switch
that reports SW_FRONT_PROXIMITY.

Reviewed-by: Datta Shubhrajyoti <shubhrajyoti@ti.com>
Signed-off-by: Courtney Cavin <courtney.cavin@sonyericsson.com>
Signed-off-by: Oskar Andero <oskar.andero@sonyericsson.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2011-12-12 00:03:36 -08:00
Mark Brown
ce37954e93 Merge branch 'topic/irq' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap into mfd/da9052 2011-12-12 13:10:02 +08:00
Mark Einon
a469ebd56f types.h: fix comment spelling for 'architectures'
Spelling change, architetures -> architectures

Signed-off-by: Mark Einon <mark.einon@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-12-12 00:30:38 +01:00
Eric Dumazet
dfd56b8b38 net: use IS_ENABLED(CONFIG_IPV6)
Instead of testing defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-11 18:25:16 -05:00
Paul E. McKenney
4968c300e1 rcu: Augment rcu_batch_end tracing for idle and callback state
The current rcu_batch_end event trace records only the name of the RCU
flavor and the total number of callbacks that remain queued on the
current CPU.  This is insufficient for testing and tuning the new
dyntick-idle RCU_FAST_NO_HZ code, so this commit adds idle state along
with whether or not any of the callbacks that were ready to invoke
at the beginning of rcu_do_batch() are still queued.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-12-11 10:32:22 -08:00
Josh Triplett
2987557f52 driver-core/cpu: Expose hotpluggability to the rest of the kernel
When architectures register CPUs, they indicate whether the CPU allows
hotplugging; notably, x86 and ARM don't allow hotplugging CPU 0.
Userspace can easily query the hotpluggability of a CPU via sysfs;
however, the kernel has no convenient way of accessing that property in
an architecture-independent way.  While the kernel can simply try it and
see, some code needs to distinguish between "hotplug failed" and
"hotplug has no hope of working on this CPU"; for example, rcutorture's
CPU hotplug tests want to avoid drowning out real hotplug failures with
expected failures.

Expose this property via a new cpu_is_hotpluggable function, so that the
rest of the kernel can access it in an architecture-independent way.

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-12-11 10:32:20 -08:00
Paul E. McKenney
7cb9249900 rcu: Permit dyntick-idle with callbacks pending
The current implementation of RCU_FAST_NO_HZ prevents CPUs from entering
dyntick-idle state if they have RCU callbacks pending.  Unfortunately,
this has the side-effect of often preventing them from entering this
state, especially if at least one other CPU is not in dyntick-idle state.
However, the resulting per-tick wakeup is wasteful in many cases: if the
CPU has already fully responded to the current RCU grace period, there
will be nothing for it to do until this grace period ends, which will
frequently take several jiffies.

This commit therefore permits a CPU that has done everything that the
current grace period has asked of it (rcu_pending() == 0) even if it
still as RCU callbacks pending.  However, such a CPU posts a timer to
wake it up several jiffies later (6 jiffies, based on experience with
grace-period lengths).  This wakeup is required to handle situations
that can result in all CPUs being in dyntick-idle mode, thus failing
to ever complete the current grace period.  If a CPU wakes up before
the timer goes off, then it cancels that timer, thus avoiding spurious
wakeups.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-12-11 10:32:07 -08:00
Paul E. McKenney
3842a0832a rcu: Document same-context read-side constraints
The intent is that a given RCU read-side critical section be confined
to a single context.  For example, it is illegal to invoke rcu_read_lock()
in an exception handler and then invoke rcu_read_unlock() from the
context of the task that received the exception.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-12-11 10:32:06 -08:00
Paul E. McKenney
f535a607c1 rcu: Eliminate RCU_FAST_NO_HZ grace-period hang
With the new implementation of RCU_FAST_NO_HZ, it was possible to hang
RCU grace periods as follows:

o	CPU 0 attempts to go idle, cycles several times through the
	rcu_prepare_for_idle() loop, then goes dyntick-idle when
	RCU needs nothing more from it, while still having at least
	on RCU callback pending.

o	CPU 1 goes idle with no callbacks.

Both CPUs can then stay in dyntick-idle mode indefinitely, preventing
the RCU grace period from ever completing, possibly hanging the system.

This commit therefore prevents CPUs that have RCU callbacks from entering
dyntick-idle mode.  This approach also eliminates the need for the
end-of-grace-period IPIs used previously.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-12-11 10:32:02 -08:00
Paul E. McKenney
433cdddcd9 rcu: Add tracing for RCU_FAST_NO_HZ
This commit adds trace_rcu_prep_idle(), which is invoked from
rcu_prepare_for_idle() and rcu_wake_cpu() to trace attempts on
the part of RCU to force CPUs into dyntick-idle mode.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-12-11 10:32:00 -08:00
Paul E. McKenney
045fb9315a rcu: Update trace_rcu_dyntick() header comment
This commit updates the trace_rcu_dyntick() header comment to reflect
events added by commit 4b4f421.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-12-11 10:31:59 -08:00
Frederic Weisbecker
1268fbc746 nohz: Remove tick_nohz_idle_enter_norcu() / tick_nohz_idle_exit_norcu()
Those two APIs were provided to optimize the calls of
tick_nohz_idle_enter() and rcu_idle_enter() into a single
irq disabled section. This way no interrupt happening in-between would
needlessly process any RCU job.

Now we are talking about an optimization for which benefits
have yet to be measured. Let's start simple and completely decouple
idle rcu and dyntick idle logics to simplify.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-12-11 10:31:57 -08:00
Paul E. McKenney
c4f3060843 sched: Add is_idle_task() to handle invalidated uses of idle_cpu()
Commit 908a3283 (Fix idle_cpu()) invalidated some uses of idle_cpu(),
which used to say whether or not the CPU was running the idle task,
but now instead says whether or not the CPU is running the idle task
in the absence of pending wakeups.  Although this new implementation
gives a better answer to the question "is this CPU idle?", it also
invalidates other uses that were made of idle_cpu().

This commit therefore introduces a new is_idle_task() API member
that determines whether or not the specified task is one of the
idle tasks, allowing open-coded "->pid == 0" sequences to be replaced
by something more meaningful.

Suggested-by: Josh Triplett <josh@joshtriplett.org>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-12-11 10:31:47 -08:00
Paul E. McKenney
4145fa7fbe rcu: Deconfuse dynticks entry-exit tracing
The trace_rcu_dyntick() trace event did not print both the old and
the new value of the nesting level, and furthermore printed only
the low-order 32 bits of it.  This could result in some confusion
when interpreting trace-event dumps, so this commit prints both
the old and the new value, prints the full 64 bits, and also selects
the process-entry/exit increment to print nicely in hexadecimal.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-12-11 10:31:42 -08:00
Paul E. McKenney
0c53dd8b31 rcu: Introduce raw SRCU read-side primitives
The RCU implementations, including SRCU, are designed to be used in a
lock-like fashion, so that the read-side lock and unlock primitives must
execute in the same context for any given read-side critical section.
This constraint is enforced by lockdep-RCU.  However, there is a need
to enter an SRCU read-side critical section within the context of an
exception and then exit in the context of the task that encountered the
exception.  The cost of this capability is that the read-side operations
incur the overhead of disabling interrupts.

Note that although the current implementation allows a given read-side
critical section to be entered by one task and then exited by another, all
known possible implementations that allow this have scalability problems.
Therefore, a given read-side critical section must be exited by the same
task that entered it, though perhaps from an interrupt or exception
handler running within that task's context.  But if you are thinking
in terms of interrupt handlers, make sure that you have considered the
possibility of threaded interrupt handlers.

Credit goes to Peter Zijlstra for suggesting use of the existing _raw
suffix to indicate disabling lockdep over the earlier "bulkref" names.

Requested-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2011-12-11 10:31:40 -08:00
Frederic Weisbecker
2bbb6817c0 nohz: Allow rcu extended quiescent state handling seperately from tick stop
It is assumed that rcu won't be used once we switch to tickless
mode and until we restart the tick. However this is not always
true, as in x86-64 where we dereference the idle notifiers after
the tick is stopped.

To prepare for fixing this, add two new APIs:
tick_nohz_idle_enter_norcu() and tick_nohz_idle_exit_norcu().

If no use of RCU is made in the idle loop between
tick_nohz_enter_idle() and tick_nohz_exit_idle() calls, the arch
must instead call the new *_norcu() version such that the arch doesn't
need to call rcu_idle_enter() and rcu_idle_exit().

Otherwise the arch must call tick_nohz_enter_idle() and
tick_nohz_exit_idle() and also call explicitly:

- rcu_idle_enter() after its last use of RCU before the CPU is put
to sleep.
- rcu_idle_exit() before the first use of RCU after the CPU is woken
up.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: David Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-12-11 10:31:36 -08:00
Frederic Weisbecker
280f06774a nohz: Separate out irq exit and idle loop dyntick logic
The tick_nohz_stop_sched_tick() function, which tries to delay
the next timer tick as long as possible, can be called from two
places:

- From the idle loop to start the dytick idle mode
- From interrupt exit if we have interrupted the dyntick
idle mode, so that we reprogram the next tick event in
case the irq changed some internal state that requires this
action.

There are only few minor differences between both that
are handled by that function, driven by the ts->inidle
cpu variable and the inidle parameter. The whole guarantees
that we only update the dyntick mode on irq exit if we actually
interrupted the dyntick idle mode, and that we enter in RCU extended
quiescent state from idle loop entry only.

Split this function into:

- tick_nohz_idle_enter(), which sets ts->inidle to 1, enters
dynticks idle mode unconditionally if it can, and enters into RCU
extended quiescent state.

- tick_nohz_irq_exit() which only updates the dynticks idle mode
when ts->inidle is set (ie: if tick_nohz_idle_enter() has been called).

To maintain symmetry, tick_nohz_restart_sched_tick() has been renamed
into tick_nohz_idle_exit().

This simplifies the code and micro-optimize the irq exit path (no need
for local_irq_save there). This also prepares for the split between
dynticks and rcu extended quiescent state logics. We'll need this split to
further fix illegal uses of RCU in extended quiescent states in the idle
loop.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: David Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-12-11 10:31:35 -08:00
Paul E. McKenney
867f236bd1 rcu: Make srcu_read_lock_held() call common lockdep-enabled function
A common debug_lockdep_rcu_enabled() function is used to check whether
RCU lockdep splats should be reported, but srcu_read_lock() does not
use it.  This commit therefore brings srcu_read_lock_held() up to date.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-12-11 10:31:34 -08:00
Paul E. McKenney
ff195cb69b rcu: Warn when srcu_read_lock() is used in an extended quiescent state
Catch SRCU up to the other variants of RCU by making PROVE_RCU
complain if either srcu_read_lock() or srcu_read_lock_held() are
used from within RCU-idle mode.

Frederic reworked this to allow for the new versions of his patches
that check for extended quiescent states.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-12-11 10:31:33 -08:00
Paul E. McKenney
d8ab29f8be rcu: Remove one layer of abstraction from PROVE_RCU checking
Simplify things a bit by substituting the definitions of the single-line
rcu_read_acquire(), rcu_read_release(), rcu_read_acquire_bh(),
rcu_read_release_bh(), rcu_read_acquire_sched(), and
rcu_read_release_sched() functions at their call points.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-12-11 10:31:32 -08:00
Frederic Weisbecker
00f49e5729 rcu: Warn when rcu_read_lock() is used in extended quiescent state
We are currently able to detect uses of rcu_dereference_check() inside
extended quiescent states (such as the RCU-free window in idle).
But rcu_read_lock() and friends can be used without rcu_dereference(),
so that the earlier commit checking for use of rcu_dereference() and
friends while in RCU idle mode miss some error conditions.  This commit
therefore adds extended quiescent state checking to rcu_read_lock() and
friends.

Uses of RCU from within RCU-idle mode are totally ignored by
RCU, hence the importance of these checks.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-12-11 10:31:31 -08:00
Frederic Weisbecker
e6b80a3b09 rcu: Detect illegal rcu dereference in extended quiescent state
Report that none of the rcu read lock maps are held while in an RCU
extended quiescent state (the section between rcu_idle_enter()
and rcu_idle_exit()). This helps detect any use of rcu_dereference()
and friends from within the section in idle where RCU is not allowed.

This way we can guarantee an extended quiescent window where the CPU
can be put in dyntick idle mode or can simply aoid to be part of any
global grace period completion while in the idle loop.

Uses of RCU from such mode are totally ignored by RCU, hence the
importance of these checks.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-12-11 10:31:30 -08:00
Paul E. McKenney
91afaf3002 rcu: Add failure tracing to rcutorture
Trace the rcutorture RCU accesses and dump the trace buffer when the
first failure is detected.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-12-11 10:31:26 -08:00
Paul E. McKenney
9b2e4f1880 rcu: Track idleness independent of idle tasks
Earlier versions of RCU used the scheduling-clock tick to detect idleness
by checking for the idle task, but handled idleness differently for
CONFIG_NO_HZ=y.  But there are now a number of uses of RCU read-side
critical sections in the idle task, for example, for tracing.  A more
fine-grained detection of idleness is therefore required.

This commit presses the old dyntick-idle code into full-time service,
so that rcu_idle_enter(), previously known as rcu_enter_nohz(), is
always invoked at the beginning of an idle loop iteration.  Similarly,
rcu_idle_exit(), previously known as rcu_exit_nohz(), is always invoked
at the end of an idle-loop iteration.  This allows the idle task to
use RCU everywhere except between consecutive rcu_idle_enter() and
rcu_idle_exit() calls, in turn allowing architecture maintainers to
specify exactly where in the idle loop that RCU may be used.

Because some of the userspace upcall uses can result in what looks
to RCU like half of an interrupt, it is not possible to expect that
the irq_enter() and irq_exit() hooks will give exact counts.  This
patch therefore expands the ->dynticks_nesting counter to 64 bits
and uses two separate bitfields to count process/idle transitions
and interrupt entry/exit transitions.  It is presumed that userspace
upcalls do not happen in the idle loop or from usermode execution
(though usermode might do a system call that results in an upcall).
The counter is hard-reset on each process/idle transition, which
avoids the interrupt entry/exit error from accumulating.  Overflow
is avoided by the 64-bitness of the ->dyntick_nesting counter.

This commit also adds warnings if a non-idle task asks RCU to enter
idle state (and these checks will need some adjustment before applying
Frederic's OS-jitter patches (http://lkml.org/lkml/2011/10/7/246).
In addition, validation of ->dynticks and ->dynticks_nesting is added.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-12-11 10:31:24 -08:00
Guennadi Liakhovetski
4c0b036db8 [media] V4L: soc-camera: fix compiler warnings on 64-bit platforms
On 64-bit platforms assigning a pointer to a 32-bit variable causes a
compiler warning and cannot actually work. Soc-camera currently doesn't
support any 64-bit systems, but such platforms can be added in the
and in any case compiler warnings should be avoided.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-12-11 09:34:00 -02:00
Stefan Nilsson XK
6de5fc9cf7 mmc: core: Add quirk for long data read time
Adds a quirk that sets the data read timeout to a fixed value instead
of relying on the information in the CSD. The timeout value chosen
is 300ms since that has proven enough for the problematic cards found,
but could be increased if other cards require this.

This patch also enables this quirk for certain Micron cards known to
have this problem.

Signed-off-by: Stefan Nilsson XK <stefan.xk.nilsson@stericsson.com>
Signed-off-by: Ulf Hansson <ulf.hansson@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: <stable@kernel.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
2011-12-10 16:18:35 -05:00
Paul Gortmaker
9deaa53ac7 serial: add irq handler for Freescale 16550 errata.
Sending a break on the SOC UARTs found in some MPC83xx/85xx/86xx
chips seems to cause a short lived IRQ storm (/proc/interrupts
typically shows somewhere between 300 and 1500 events).  Unfortunately
this renders SysRQ over the serial console completely inoperable.

The suggested workaround in the errata is to read the Rx register,
wait one character period, and then read the Rx register again.
We achieve this by tracking the old LSR value, and on the subsequent
interrupt event after a break, we don't read LSR, instead we just
read the RBR again and return immediately.

The "fsl,ns16550" is used in the compatible field of the serial
device to mark UARTs known to have this issue.

Thanks to Scott Wood for providing the errata data which led to
a much cleaner fix.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-12-09 19:14:13 -08:00
Paul Gortmaker
3986fb2ba6 serial: export the key functions for an 8250 IRQ handler
For drivers that need to construct their own IRQ handler, the
three components are seen in the current handle_port -- i.e.
Rx, Tx and modem_status.

Make these exported symbols so that "almost" 8250 UARTs can
construct their own IRQ handler with these shared components,
while working around their own unique errata issues.

The function names are given a serial8250 prefix, since they
are now entering the global namespace.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-12-09 19:14:13 -08:00
Matt Fleming
55839d5154 efi: Add EFI file I/O data types
The x86 EFI stub needs to access files, for example when loading
initrd's. Add the required data types.

Cc: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1318848017-12301-1-git-send-email-matt@console-pimps.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-12-09 17:35:51 -08:00
Matt Fleming
e2527a7cbe efi.h: Add boottime->locate_handle search types
The x86 EFI boot stub needs to locate handles for various protocols.

Cc: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1318848017-12301-1-git-send-email-matt@console-pimps.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-12-09 17:35:49 -08:00
Matt Fleming
0f7c5d477f efi.h: Add graphics protocol guids
The x86 EFI boot stub uses the Graphics Output Protocol and Universal
Graphics Adapter (UGA) protocol guids when initialising graphics
during boot.

Cc: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1318848017-12301-1-git-send-email-matt@console-pimps.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-12-09 17:35:46 -08:00