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path: root/kernel/irq/internals.h
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2012-03-13Merge branch 'linus' into irq/coreThomas Gleixner
Reason: Get upstream fixes integrated before further modifications. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-09genirq: Get rid of unnecessary IRQTF_DIED flagAlexander Gordeev
Currently IRQTF_DIED flag is set when a IRQ thread handler calls do_exit() But also PF_EXITING per process flag gets set when a thread exits. This fix eliminates the duplicate by using PF_EXITING flag. Also, there is a race condition in exit_irq_thread(). In case a thread's bit is cleared in desc->threads_oneshot (and the IRQ line gets unmasked), but before IRQTF_DIED flag is set, a new interrupt might come in and set just cleared bit again, this time forever. This fix throws IRQTF_DIED flag away, eliminating the race as a result. [ tglx: Test THREAD_EXITING first as suggested by Oleg ] Reported-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Link: http://lkml.kernel.org/r/20120309135958.GD2114@dhcp-26-207.brq.redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-02-15genirq: Handle pending irqs in irq_startup()Thomas Gleixner
An interrupt might be pending when irq_startup() is called, but the startup code does not invoke the resend logic. In some cases this prevents the device from issuing another interrupt which renders the device non functional. Call the resend function in irq_startup() to keep things going. Reported-and-tested-by: Russell King <rmk+kernel@arm.linux.org.uk> Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-01-13module_param: make bool parameters really bool (core code)Rusty Russell
module_param(bool) used to counter-intuitively take an int. In fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy trick. It's time to remove the int/unsigned int option. For this version it'll simply give a warning, but it'll break next kernel version. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-10-03genirq: Add support for per-cpu dev_id interruptsMarc Zyngier
The ARM GIC interrupt controller offers per CPU interrupts (PPIs), which are usually used to connect local timers to each core. Each CPU has its own private interface to the GIC, and only sees the PPIs that are directly connect to it. While these timers are separate devices and have a separate interrupt line to a core, they all use the same IRQ number. For these devices, request_irq() is not the right API as it assumes that an IRQ number is visible by a number of CPUs (through the affinity setting), but makes it very awkward to express that an IRQ number can be handled by all CPUs, and yet be a different interrupt line on each CPU, requiring a different dev_id cookie to be passed back to the handler. The *_percpu_irq() functions is designed to overcome these limitations, by providing a per-cpu dev_id vector: int request_percpu_irq(unsigned int irq, irq_handler_t handler, const char *devname, void __percpu *percpu_dev_id); void free_percpu_irq(unsigned int, void __percpu *); int setup_percpu_irq(unsigned int irq, struct irqaction *new); void remove_percpu_irq(unsigned int irq, struct irqaction *act); void enable_percpu_irq(unsigned int irq); void disable_percpu_irq(unsigned int irq); The API has a number of limitations: - no interrupt sharing - no threading - common handler across all the CPUs Once the interrupt is requested using setup_percpu_irq() or request_percpu_irq(), it must be enabled by each core that wishes its local interrupt to be delivered. Based on an initial patch by Thomas Gleixner. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1316793788-14500-2-git-send-email-marc.zyngier@arm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-03-29genirq: Remove compat codeThomas Gleixner
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-03-28genirq: Move INPROGRESS, MASKED and DISABLED state flags to irq_dataThomas Gleixner
We really need these flags for some of the interrupt chips. Move it from internal state to irq_data and provide proper accessors. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: David Daney <ddaney@caviumnetworks.com>
2011-02-26genirq: Provide forced interrupt threadingThomas Gleixner
Add a commandline parameter "threadirqs" which forces all interrupts except those marked IRQF_NO_THREAD to run threaded. That's mostly a debug option to allow retrieving better debug data from crashing interrupt handlers. If "threadirqs" is not enabled on the kernel command line, then there is no impact in the interrupt hotpath. Architecture code needs to select CONFIG_IRQ_FORCED_THREADING after marking the interrupts which cant be threaded IRQF_NO_THREAD. All interrupts which have IRQF_TIMER set are implict marked IRQF_NO_THREAD. Also all PER_CPU interrupts are excluded. Forced threading hard interrupts also forces all soft interrupt handling into thread context. When enabled it might slow down things a bit, but for debugging problems in interrupt code it's a reasonable penalty as it does not immediately crash and burn the machine when an interrupt handler is buggy. Some test results on a Core2Duo machine: Cache cold run of: # time git grep irq_desc non-threaded threaded real 1m18.741s 1m19.061s user 0m1.874s 0m1.757s sys 0m5.843s 0m5.427s # iperf -c server non-threaded [ 3] 0.0-10.0 sec 1.09 GBytes 933 Mbits/sec [ 3] 0.0-10.0 sec 1.09 GBytes 934 Mbits/sec [ 3] 0.0-10.0 sec 1.09 GBytes 933 Mbits/sec threaded [ 3] 0.0-10.0 sec 1.09 GBytes 939 Mbits/sec [ 3] 0.0-10.0 sec 1.09 GBytes 934 Mbits/sec [ 3] 0.0-10.0 sec 1.09 GBytes 937 Mbits/sec Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> LKML-Reference: <20110223234956.772668648@linutronix.de>
2011-02-19genirq: Implement irq_get/put_desc_[bus]locked/unlock()Thomas Gleixner
Most of the managing functions get the irq descriptor and lock it - either with or without buslock. Instead of open coding this over and over provide a common function to do that. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Remove real old transition functionsThomas Gleixner
These transition helpers are stale for years now. Remove them. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Remove desc->status when GENERIC_HARDIRQS_NO_COMPAT=yThomas Gleixner
If everything uses the right accessors, then enabling GENERIC_HARDIRQS_NO_COMPAT should just work. If not it will tell you. Don't be lazy and use the trick which I use in the core code! git grep status_use_accessors will unearth it in a split second. Offenders are tracked down and not slapped with stinking trouts. This time we use frozen shark for a better educational value. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Move wakeup state to irq_dataThomas Gleixner
Some irq_chips need to know the state of wakeup mode for setting the trigger type etc. Reflect it in irq_data state. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Add IRQCHIP_SET_TYPE_MASKED flagThomas Gleixner
irq_chips, which require to mask the chip before changing the trigger type should set this flag. So the core takes care of it and the requirement for looking into desc->status in the chip goes away. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Walleij <linus.walleij@stericsson.com> Cc: Lars-Peter Clausen <lars@metafoo.de>
2011-02-19genirq: Move IRQ_AFFINITY_SET to coreThomas Gleixner
Keep status in sync until last abuser is gone. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Mirror IRQ_PER_CPU and IRQ_NO_BALANCING in irq_data.stateThomas Gleixner
That's the right data structure to look at for arch code. Accessor functions are provided. irqd_is_per_cpu(irqdata); irqd_can_balance(irqdata); Coders who access them directly will be tracked down and slapped with stinking trouts. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Move debug code to separate headerThomas Gleixner
It'll break when I'm going to undefine the constants. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Remove CONFIG_IRQ_PER_CPUThomas Gleixner
The saving of this switch is minimal versus the ifdef mess it creates. Simple enable PER_CPU unconditionally and remove the config switch. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Add IRQ_MOVE_PENDING to irq_data.stateThomas Gleixner
chip implementations need to know about it. Keep status in sync until all users are fixed. Accessor function: irqd_is_setaffinity_pending(irqdata) Coders who access them directly will be tracked down and slapped with stinking trouts. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Move IRQ_WAKEUP to coreThomas Gleixner
No users outside of core. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Move IRQ_SUSPENDED to coreThomas Gleixner
No users outside of core. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Move IRQ_MASKED to coreThomas Gleixner
Keep status in sync until all users are fixed. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Move IRQ_PENDING flag to coreThomas Gleixner
Keep status in sync until all users are fixed. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Move IRQ_DISABLED to coreThomas Gleixner
Keep status in sync until all abusers are fixed. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Move IRQ_REPLAY and IRQ_WAITING to coreThomas Gleixner
No users outside of core. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Move IRQ_ONESHOT to coreThomas Gleixner
No users outside of core. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Add IRQ_INPROGRESS to coreThomas Gleixner
We need to maintain the flag for now in both fields status and istate. Add a CONFIG_GENERIC_HARDIRQS_NO_COMPAT switch to allow testing w/o the status one. Wrap the access to status IRQ_INPROGRESS in a inline which can be turned of with CONFIG_GENERIC_HARDIRQS_NO_COMPAT along with the define. There is no reason that anything outside of core looks at this. That needs some modifications, but we'll get there. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Move IRQ_POLL_INPROGRESS to coreThomas Gleixner
No users outside of core. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Move IRQ_SPURIOUS_DISABLED to core stateThomas Gleixner
No users outside. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Move IRQ_AUTODETECT to internal stateThomas Gleixner
No users outside of core Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Protect tglx from tripping over his own feetThomas Gleixner
The irq_desc.status field will either go away or renamed to settings. Anyway we need to maintain compatibility to avoid breaking the world and some more. While moving bits into the core, I need to avoid that I use any of the still existing IRQ_ bits in the core code by typos. So that file will hold the inline wrappers and some nasty CPP tricks to break the build when typoed. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Add internal state field to irq_descThomas Gleixner
That field will contain internal state information which is not going to be exposed to anything outside the core code - except via accessor functions. I'm tired of everyone fiddling in irq_desc.status. core_internal_state__do_not_mess_with_it is clear enough, annoying to type and easy to grep for. Offenders will be tracked down and slapped with stinking trouts. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Implement handle_irq_event()Thomas Gleixner
Core code replacement for the ugly camel case. It contains all the code which is shared in all handlers. clear status flags set INPROGRESS flag unlock call action chain note_interrupt lock clr INPROGRESS flag Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Consolidate disable/enableThomas Gleixner
Create irq_disable/enable and use them to keep the flags consistent. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Consolidate startup/shutdown of interruptsThomas Gleixner
Aside of duplicated code some of the startup/shutdown sites do not handle the MASKED/DISABLED flags and the depth field at all. Move that to a helper function and take care of it there. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> LKML-Reference: <20110202212551.787481468@linutronix.de>
2011-02-19genirq: Move irq thread flags to coreThomas Gleixner
Soleley used in core code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Mark polled irqs and defer the real handlerThomas Gleixner
With the chip.end() function gone we might run into a situation where a poll call runs and the real interrupt comes in, sees IRQ_INPROGRESS and disables the line. That might be a perfect working one, which will then be masked forever. So mark them polled while the poll runs. When the real handler sees IRQ_INPROGRESS it checks the poll flag and waits for the polling to complete. Add the necessary amount of sanity checks to it to avoid deadlocks. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Do not copy affinity before setThomas Gleixner
While rumaging through arch code I found that there are a few workarounds which deal with the fact that the initial affinity setting from request_irq() copies the mask into irq_data->affinity before the chip code is called. In the normal path we unconditionally copy the mask when the chip code returns 0. Copy after the code is called and add a return code IRQ_SET_MASK_OK_NOCOPY for the chip functions, which prevents the copy. That way we see the real mask when the chip function decided to truncate it further as some arches do. IRQ_SET_MASK_OK is 0, which is the current behaviour. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19genirq: Prevent access beyond allocated_irqs bitmapThomas Gleixner
Lars-Peter Clausen pointed out: I stumbled upon this while looking through the existing archs using SPARSE_IRQ. Even with SPARSE_IRQ the NR_IRQS is still the upper limit for the number of IRQs. Both PXA and MMP set NR_IRQS to IRQ_BOARD_START, with IRQ_BOARD_START being the number of IRQs used by the core. In various machine files the nr_irqs field of the ARM machine defintion struct is then set to "IRQ_BOARD_START + NR_BOARD_IRQS". As a result "nr_irqs" will greater then NR_IRQS which then again causes the "allocated_irqs" bitmap in the core irq code to be accessed beyond its size overwriting unrelated data. The core code really misses a sanity check there. This went unnoticed so far as by chance the compiler/linker places data behind that bitmap which gets initialized later on those affected platforms. So the obvious fix would be to add a sanity check in early_irq_init() and break all affected platforms. Though that check wants to be backported to stable as well, which will require to fix all known problematic platforms and probably some more yet not known ones as well. Lots of churn. A way simpler solution is to allocate a slightly larger bitmap and avoid the whole churn w/o breaking anything. Add a few warnings when an arch returns utter crap. Reported-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@kernel.org # .37 Cc: Haojian Zhuang <haojian.zhuang@marvell.com> Cc: Eric Miao <eric.y.miao@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org>
2010-10-12genirq: Remove the now unused sparse irq leftoversThomas Gleixner
The move_irq_desc() function was only used due to the problem that the allocator did not free the old descriptors. So the descriptors had to be moved in create_irq_nr(). That's history. The code would have never been able to move active interrupt descriptors on affinity settings. That can be done in a completely different way w/o all this horror. Remove all of it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-10-12genirq: Sanitize dynamic irq handlingThomas Gleixner
Use the cleanup functions of the dynamic allocator. No need to have separate implementations. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-10-12genirq: Prepare proc for real sparse irq supportThomas Gleixner
/proc/irq never removes any entries, but when irq descriptors can be freed for real this is necessary. Otherwise we'd reference a freed descriptor in /proc/irq/N Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-10-12genirq: Distangle irq.hThomas Gleixner
Move irq_desc and internal functions out of irq.h Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-10-04genirq: Provide config option to disable deprecated codeThomas Gleixner
This option covers now the old chip functions and the irq_desc data fields which are moving to struct irq_data. More stuff will follow. Pretty handy for testing a conversion, whether something broke or not. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-10-04genirq: Provide compat handling for bus_lock/bus_sync_unlockThomas Gleixner
Wrap the old chip functions for bus_lock/bus_sync_unlock until the migration is complete and the old chip functions are removed. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> LKML-Reference: <20100927121841.842536121@linutronix.de> Reviewed-by: H. Peter Anvin <hpa@zytor.com> Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-10-04genirq: Add new functions to dummy chipsThomas Gleixner
The compat functions go away when the core code is converted. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-10-04genirq: Convert core code to irq_dataThomas Gleixner
Convert all references in the core code to orq, chip, handler_data, chip_data, msi_desc, affinity to irq_data.* Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-02-17sparseirq: Change irq_desc_ptrs to staticYinghai Lu
Add replace_irq_desc() instead of poking at the array directly. -v2: remove unneeded boundary check in replace_irq_desc Signed-off-by: Yinghai Lu <yinghai@kernel.org> LKML-Reference: <1265793639-15071-31-git-send-email-yinghai@kernel.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-12-14genirq: Convert irq_desc.lock to raw_spinlockThomas Gleixner
Convert locks which cannot be sleeping locks in preempt-rt to raw_spinlocks. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Ingo Molnar <mingo@elte.hu>
2009-08-17genirq: Add buslock supportThomas Gleixner
Some interrupt chips are connected to a "slow" bus (i2c, spi ...). The bus access needs to sleep and therefor cannot be called in atomic contexts. Some of the generic interrupt management functions like disable_irq(), enable_irq() ... call interrupt chip functions with the irq_desc->lock held and interrupts disabled. This does not work for such devices. Provide a separate synchronization mechanism for such interrupt chips. The irq_chip structure is extended by two optional functions (bus_lock and bus_sync_and_unlock). The idea is to serialize the bus access for those operations in the core code so that drivers which are behind that bus operated interrupt controller do not have to worry about it and just can use the normal interfaces. To achieve this we add two function pointers to the irq_chip: bus_lock and bus_sync_unlock. bus_lock() is called to serialize access to the interrupt controller bus. Now the core code can issue chip->mask/unmask ... commands without changing the fast path code at all. The chip implementation merily stores that information in a chip private data structure and returns. No bus interaction as these functions are called from atomic context. After that bus_sync_unlock() is called outside the atomic context. Now the chip implementation issues the bus commands, waits for completion and unlocks the interrupt controller bus. The irq_chip implementation as pseudo code: struct irq_chip_data { struct mutex mutex; unsigned int irq_offset; unsigned long mask; unsigned long mask_status; } static void bus_lock(unsigned int irq) { struct irq_chip_data *data = get_irq_desc_chip_data(irq); mutex_lock(&data->mutex); } static void mask(unsigned int irq) { struct irq_chip_data *data = get_irq_desc_chip_data(irq); irq -= data->irq_offset; data->mask |= (1 << irq); } static void unmask(unsigned int irq) { struct irq_chip_data *data = get_irq_desc_chip_data(irq); irq -= data->irq_offset; data->mask &= ~(1 << irq); } static void bus_sync_unlock(unsigned int irq) { struct irq_chip_data *data = get_irq_desc_chip_data(irq); if (data->mask != data->mask_status) { do_bus_magic_to_set_mask(data->mask); data->mask_status = data->mask; } mutex_unlock(&data->mutex); } The device drivers can use request_threaded_irq, free_irq, disable_irq and enable_irq as usual with the only restriction that the calls need to come from non atomic context. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Trilok Soni <soni.trilok@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Brian Swetland <swetland@google.com> Cc: Joonyoung Shim <jy0922.shim@samsung.com> Cc: m.szyprowski@samsung.com Cc: t.fujak@samsung.com Cc: kyungmin.park@samsung.com, Cc: David Brownell <david-b@pacbell.net> Cc: Daniel Ribeiro <drwyrm@gmail.com> Cc: arve@android.com Cc: Barry Song <21cnbao@gmail.com>
2009-07-21genirq: Delegate irq affinity setting to the irq threadThomas Gleixner
irq_set_thread_affinity() calls set_cpus_allowed_ptr() which might sleep, but irq_set_thread_affinity() is called with desc->lock held and can be called from hard interrupt context as well. The code has another bug as it does not hold a ref on the task struct as required by set_cpus_allowed_ptr(). Just set the IRQTF_AFFINITY bit in action->thread_flags. The next time the thread runs it migrates itself. Solves all of the above problems nicely. Add kerneldoc to irq_set_thread_affinity() while at it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> LKML-Reference: <new-submission>