The user space interface does not filter out offline cpus. It merily
verifies that the mask contains at least one online cpu. So the
selector in the irq chip implementation needs to make sure to pick
only an online cpu because otherwise:
Offline Core 1
Set affinity to 0xe
Selector will pick first set bit, i.e. core 1
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Xen <xen-devel@lists.xenproject.org>
Link: http://lkml.kernel.org/r/20140304203100.978031089@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The [user space] interface does not filter out offline cpus. It merily
guarantees that the mask contains at least one online cpu.
So the selector in the irq chip implementation needs to make sure to
pick only an online cpu because otherwise:
Offline Core 1
Set affinity to 0xe (is valid due to online mask 0xd)
cpumask_first will pick core 1, which is offline
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Link: http://lkml.kernel.org/r/20140304203100.744800502@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The [user space] interface does not filter out offline cpus. It merily
guarantees that the mask contains at least one online cpu.
So the selector in the irq chip implementation needs to make sure to
pick only an online cpu because otherwise:
Offline Core 1
Set affinity to 0xe (is valid due to online mask 0xd)
cpumask_first will pick core 1, which is offline
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: ia64 <linux-ia64@vger.kernel.org>
Link: http://lkml.kernel.org/r/20140304203100.650414633@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LTO patches add __visible to the asmlinkage define, causing
compilation warnings like:
drivers/irqchip/irq-gic.c:283:1: warning: 'externally_visible'
attribute have effect only on public objects [-Wattributes]
Drop asmlinkage here to avoid such warnings.
Reported-by: Olof's autobuilder <build@lixom.net>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: khilman@linaro.org
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Josh Cartwright <joshc@codeaurora.org>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1393980030-17770-1-git-send-email-sboyd@codeaurora.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
drivers/irqchip/irq-gic.c:53:23: warning: duplicate [noderef]
drivers/irqchip/irq-gic.c:651:6: warning: symbol 'gic_raise_softirq' was not declared. Should it be static?
drivers/irqchip/irq-gic.c:872:29: warning: symbol 'gic_irq_domain_ops' was not declared. Should it be static?
drivers/irqchip/irq-gic.c:977:12: warning: symbol 'gic_of_init' was not declared. Should it be static?
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1393981321-25721-1-git-send-email-sboyd@codeaurora.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Compiling last minute changes without setting the proper config
options is not really clever.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
commit: 8f945a33 (genirq: Move kstat_incr_irqs_this_cpu() to core)
unearthed the following:
arch/m68k/kernel/ints.c:34:15: error: variable 'auto_irq_chip' has initializer but incomplete type
arch/m68k/kernel/ints.c:35:2: error: unknown field 'name' specified in initializer
arch/m68k/kernel/ints.c:35:2: warning: excess elements in struct initializer [enabled by default]
The reason is that this file requires linux/irq.h and magically
pulled that in via linux/kernel_stat.h
The commit above got rid of the pointless include of linux/irq.h in
linux/kernel_stat.h and therefor broke the build.
Include linux/irq.h
Reported-by: fengguang.wu@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Commit b8a9a11b9 (powerpc: eeh: Kill another abuse of irq_desc) is
missing some brackets .....
It's not a good idea to write patches in grumpy mode and then forget
to at least compile test them or rely on the few eyeballs discussing
that patch to spot it.....
Reported-by: fengguang.wu@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Gavin Shan <shangw@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: ppc <linuxppc-dev@lists.ozlabs.org>
commit: 8f945a33 (genirq: Move kstat_incr_irqs_this_cpu() to core)
unearthed the following:
arch/s390/kernel/irq.c: In function 'init_IRQ':
>> arch/s390/kernel/irq.c:93:2: error: implicit declaration of function 'irq_reserve_irqs'
[-Werror=implicit-function-declaration]
....
cc1: some warnings being treated as errors
--
drivers/s390/cio/cio.c: In function 'init_cio_interrupts':
>> drivers/s390/cio/cio.c:594:2: error: implicit declaration of function
'irq_set_chip_and_handler' [-Werror=implicit-function-declaration]
[-Werror=implicit-function-declaration]
....
cc1: some warnings being treated as errors
The reason is that those files require linux/irq.h and magically
pulled that in via linux/kernel_stat.h
The commit above got rid of the pointless include of linux/irq.h in
linux/kernel_stat.h and therefor broke the build.
Include linux/irq.h
Reported-by: fengguang.wu@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: s390 <linux-s390@vger.kernel.org>
Reported-by: fengguang.wu@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linuxdrivers <devel@linuxdriverproject.org>
Cc: x86 <x86@kernel.org>
Commit 1aec16967 (x86: Hyperv: Cleanup the irq mess) removed the
ability to build the hyperv stuff as a module. Bring it back.
Reported-by: fengguang.wu@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linuxdrivers <devel@linuxdriverproject.org>
Cc: x86 <x86@kernel.org>
There is no point in having an incomplete copy of irq_set_affinity()
for the hotplug irq migration code.
Use the core function instead and while at it switch to
for_each_active_irq()
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: xtensa <linux-xtensa@linux-xtensa.org>
Link: http://lkml.kernel.org/r/20140223212736.664624945@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The user space interface does not filter out offline cpus. It merily
verifies that the mask contains at least one online cpu. So the
selector in the irq chip implementation needs to make sure to pick
only an online cpu because otherwise:
Offline Core 1
Set affinity to 0xe
Selector will pick first set bit, i.e. core 1
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Chris Zankel <chris@zankel.net>
Cc: xtensa <linux-xtensa@linux-xtensa.org>
There is no point in having an incomplete copy of irq_set_affinity()
for the hotplug irq migration code.
Use the core function instead.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: sh <linux-sh@vger.kernel.org>
Link: http://lkml.kernel.org/r/20140223212736.774961401@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
No more users outside the core code. Put it into the poison
cabinet. That also gets rid of the linux/irq.h include in
kernel_stat.h
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140223212739.124207133@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The vmbus/hyperv interrupt handling is another complete trainwreck and
probably the worst of all currently in tree.
If CONFIG_HYPERV=y then the interrupt delivery to the vmbus happens
via the direct HYPERVISOR_CALLBACK_VECTOR. So far so good, but:
The driver requests first a normal device interrupt. The only reason
to do so is to increment the interrupt stats of that device
interrupt. For no reason it also installs a private flow handler.
We have proper accounting mechanisms for direct vectors, but of
course it's too much effort to add that 5 lines of code.
Aside of that the alloc_intr_gate() is not protected against
reallocation which makes module reload impossible.
Solution to the problem is simple to rip out the whole mess and
implement it correctly.
First of all move all that code to arch/x86/kernel/cpu/mshyperv.c and
merily install the HYPERVISOR_CALLBACK_VECTOR with proper reallocation
protection and use the proper direct vector accounting mechanism.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linuxdrivers <devel@linuxdriverproject.org>
Cc: x86 <x86@kernel.org>
Link: http://lkml.kernel.org/r/20140223212739.028307673@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
HyperV abuses a device interrupt to account for the
HYPERVISOR_CALLBACK_VECTOR.
Provide proper accounting as we have for the other vectors as well.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: x86 <x86@kernel.org>
Link: http://lkml.kernel.org/r/20140223212738.681855582@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Let the core do the irq_desc resolution.
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: ia64 <linux-ia64@vger.kernel.org>
Link: http://lkml.kernel.org/r/20140223212738.099977064@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Let the core do the irq_desc resolution.
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: s390 <linux-s390@vger.kernel.org>
Link: http://lkml.kernel.org/r/20140223212737.983433636@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Let the core do the irq_desc resolution.
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: David Howells <dhowells@redhat.com>
Cc: mn10300 <linux-am33-list@redhat.com>
Link: http://lkml.kernel.org/r/20140223212737.751487689@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Let the core do the irq_desc resolution.
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Xen <xen-devel@lists.xenproject.org>
Cc: x86 <x86@kernel.org>
Link: http://lkml.kernel.org/r/20140223212737.869264085@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Let the core do the irq_desc resolution.
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: David S. Miller <davem@davemloft.net>
Link: http://lkml.kernel.org/r/20140223212737.635609567@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Let the core do the irq_desc resolution.
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: mips <inux-mips@linux-mips.org>
Link: http://lkml.kernel.org/r/20140223212737.517340416@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
There is a common pattern all over the place:
kstat_incr_irqs_this_cpu(irq, irq_to_desc(irq));
This results in a call to core code anyway. So provide a function
which does the same thing in core.
While at it, replace the butt ugly macro with an inline.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140223212737.422068876@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Warn if any PIRQ cannot be bound to an event channel. Remove the check
for irq_desc->action. This hypercall never fails in practice so we can
emit a warning unconditionally.
Remove a check for a valid irq desc. The only caller of
xen_destroy_irq() will only do so if the irq was previously fully
setup, which means the descriptor has been allocated as well.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Xen <xen-devel@lists.xenproject.org>
Cc: David Vrabel <david.vrabel@citrix.com>
Link: http://lkml.kernel.org/r/20140223212738.579581220@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
generic_handler_irq() already tests for !desc so use this instead of
generic_handle_irq_desc().
Use irq_get_irq_data() instead of desc->irq_data.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Xen <xen-devel@lists.xenproject.org>
Link: http://lkml.kernel.org/r/20140223212738.222412125@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The pm-mmp2 and pm-pxa910 power management related irq_set_wake
callbacks fiddle pointlessly with the irq actions for no reason except
for lack of understanding how the wakeup mechanism works.
On supsend the core disables all interrupts lazily, i.e. it does not
mask them at the irq controller level. So any interrupt which is
firing during suspend will mark the corresponding interrupt line as
pending. Just before the core powers down it checks whether there are
interrupts pending from interrupt lines which are marked as wakeup
sources and if so it aborts the suspend and resends the interrupts.
If there was no interrupt at this point, the cpu goes into suspend
with these interrupts unmasked.
The IRQF_NO_SUSPEND flag for interrupt actions is a totally different
mechanism. That allows the device driver to prevent the core from
disabling the interrupt despite the fact that it is not marked as a
wakeup source. This has nothing to do with the case at hand. It was
introduced for special cases where lazy disable is not possible.
Remove the nonsense along with the braindamaged boundary check. The
core code does NOT call these functions out of boundary.
Add a FIXME comment to an unhandled error path which merily printks
some useless blurb instead of returning a proper error code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: arm <linux-arm-kernel@lists.infradead.org>
Cc: Eric Miao <eric.y.miao@gmail.com>
Cc: Haojian Zhuang <haojian.zhuang@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Link: http://lkml.kernel.org/r/20140223212737.214342433@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Use the proper functions. There is no need to fiddle with irq_desc.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Shawn Guo <shawn.guo@linaro.org>C
Acked-by: Tony Lindgren <tony@atomide.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: arm <linux-arm-kernel@lists.infradead.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Link: http://lkml.kernel.org/r/20140223212737.099151500@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
There is no reason to care about irq_desc in that context, escpecially
as irq_data for that interrupt is retrieved as well.
Use the proper accessor for the msi descriptor
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Cc: Mohit Kumar <mohit.kumar@st.com>
Cc: pci <linux-pci@vger.kernel.org>
Link: http://lkml.kernel.org/r/20140223212736.987803648@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
commit 91150af3a (powerpc/eeh: Fix unbalanced enable for IRQ) is
another brilliant example of trainwreck engineering.
The patch "fixes" the issue of an unbalanced call to irq_enable()
which causes a prominent warning by checking the disabled state of the
interrupt line and call conditionally into the core code.
This is wrong in two aspects:
1) The warning is there to tell users, that they need to fix their
asymetric enable/disable patterns by finding the root cause and
solving it there.
It's definitely not meant to work around it by conditionally
calling into the core code depending on the random state of the irq
line.
Asymetric irq_disable/enable calls are a clear sign of wrong usage
of the interfaces which have to be cured at the root and not by
somehow hacking around it.
2) The abuse of core internal data structure instead of using the
proper interfaces for retrieving the information for the 'hack
around'
irq_desc is core internal and it's clear enough stated.
Replace at least the irq_desc abuse with the proper functions and add
a big fat comment why this is absurd and completely wrong.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Gavin Shan <shangw@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: ppc <linuxppc-dev@lists.ozlabs.org>
Link: http://lkml.kernel.org/r/20140223212736.562906212@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
No functional change
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: ppc <linuxppc-dev@lists.ozlabs.org>
Link: http://lkml.kernel.org/r/20140223212736.333718121@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
I'm really grumpy about this one. The line:
#include "../../../kernel/irq/settings.h"
should have been an alarm sign for all people who added their SOB to
this trainwreck.
When I cleaned up the mess people made with interrupt descriptors a
few years ago, I warned that I'm going to hunt down new offenders and
treat them with stinking trouts. In this case I'll use frozen shark
for a better educational value.
The whole idiocy which was done there could have been avoided with two
lines of perfectly fine code. And do not complain about the lack of
correct examples in tree.
The solution is simple:
Remove the brainfart and use the proper functions, which should
have been used in the first place
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ashish Kalra <ashish.kalra@freescale.com>
Cc: Timur Tabi <timur@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: ppc <linuxppc-dev@lists.ozlabs.org>
Link: http://lkml.kernel.org/r/20140223212736.451970660@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This reverts commit 40b367d95f.
Russell King has raised the idea of creating a proper PMU driver for
this SoC that would incorporate the functionality currently in this
driver. It would also cover the use case for the graphics subsystem on
this SoC.
To prevent having to maintain the devicetree ABI for this limited
interrupt-handler driver, we revert the driver before it hits a mainline
tagged release (eg v3.15).
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@googlemail.com>
Cc: Gregory CLEMENT <gregory.clement@free-electrons.com>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Link: http://lkml.kernel.org/r/1393911160-7688-1-git-send-email-jason@lakedaemon.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The new Armada 375 and Armada 38x Marvell SoCs are based on Cortex-A9
CPU cores and use the ARM GIC as their main interrupt controller.
However, for various purposes (wake-up from suspend, MSI interrupts),
they have kept a separate MPIC interrupt controller, acting as a slave
to the GIC. This MPIC was already used as the primary controller on
previous Marvell SoCs, so this commit extends the existing driver to
allow the MPIC to be used as a GIC slave.
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
Introduce a helper function to handle the MSI interrupts. This makes
the code more readable. In addition, this will allow to introduce a
chained IRQ handler mechanism, which is needed in situations where the
MPIC is used as a slave to another interrupt controller.
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
Pull the functionality which is required to cleanup sdhci/sdio
in. It's in a separate branch so it can be pulled from others
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
In course of the sdhci/sdio discussion with Russell about killing the
sdio kthread hackery we discovered the need to be able to wake an
interrupt thread from software.
The rationale for this is, that sdio hardware can lack proper
interrupt support for certain features. So the driver needs to poll
the status registers, but at the same time it needs to be woken up by
an hardware interrupt.
To be able to get rid of the home brewn kthread construct of sdio we
need a way to wake an irq thread independent of an actual hardware
interrupt.
Provide an irq_wake_thread() function which wakes up the thread which
is associated to a given dev_id. This allows sdio to invoke the irq
thread from the hardware irq handler via the IRQ_WAKE_THREAD return
value and provides a possibility to wake it via a timer for the
polling scenarios. That allows to simplify the sdio logic
significantly.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Chris Ball <chris@printf.net>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140215003823.772565780@linutronix.de
synchronize_irq() waits for hard irq and threaded handlers to complete
before returning. For some special cases we only need to make sure
that the hard interrupt part of the irq line is not in progress when
we disabled the - possibly shared - interrupt at the device level.
A proper use case for this was provided by Russell. The sdhci driver
requires some irq triggered functions to be run in thread context. The
current implementation of the thread context is a sdio private kthread
construct, which has quite some shortcomings. These can be avoided
when the thread is directly associated to the device interrupt via the
generic threaded irq infrastructure.
Though there is a corner case related to run time power management
where one side disables the device interrupts at the device level and
needs to make sure, that an already running hard interrupt handler has
completed before proceeding further. Though that hard interrupt
handler might wake the associated thread, which in turn can request
the runtime PM to reenable the device. Using synchronize_irq() leads
to an immediate deadlock of the irq thread waiting for the PM lock and
the synchronize_irq() waiting for the irq thread to complete.
Due to the fact that it is sufficient for this case to ensure that no
hard irq handler is executing a new function which avoids the check
for the thread is required.
Add a function, which just monitors the hard irq parts and ignores the
threaded handlers.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Russell King <linux@arm.linux.org.uk>
Cc: Chris Ball <chris@printf.net>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140215003823.653236081@linutronix.de
Pull btrfs fixes from Chris Mason:
"We have a small collection of fixes in my for-linus branch.
The big thing that stands out is a revert of a new ioctl. Users
haven't shipped yet in btrfs-progs, and Dave Sterba found a better way
to export the information"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: use right clone root offset for compressed extents
btrfs: fix null pointer deference at btrfs_sysfs_add_one+0x105
Btrfs: unset DCACHE_DISCONNECTED when mounting default subvol
Btrfs: fix max_inline mount option
Btrfs: fix a lockdep warning when cleaning up aborted transaction
Revert "btrfs: add ioctl to export size of global metadata reservation"
