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path: root/kernel/irq/irqdesc.c
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2015-06-20Merge branch 'irq/for-x86' into irq/coreThomas Gleixner
Get the infrastructure patches which are required for x86/apic into core
2015-06-12genirq: Introduce helper function irq_data_get_node()Jiang Liu
Introduce helper function irq_data_get_node() and variants thereof to hide struct irq_data implementation details. Convert the core code to use them. Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Jason Cooper <jason@lakedaemon.net> Cc: Kevin Cernekee <cernekee@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Link: http://lkml.kernel.org/r/1433145945-789-5-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-06-12genirq: Introduce struct irq_common_data to host shared irq dataJiang Liu
With the introduction of hierarchy irqdomain, struct irq_data becomes per-chip instead of per-irq and there may be multiple irq_datas associated with the same irq. Some per-irq data stored in struct irq_data now may get duplicated into multiple irq_datas, and causes inconsistent view. So introduce struct irq_common_data to host per-irq common data and to achieve consistent view among irq_chips. Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Jason Cooper <jason@lakedaemon.net> Cc: Kevin Cernekee <cernekee@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Marc Zyngier <marc.zyngier@arm.com> Link: http://lkml.kernel.org/r/1433145945-789-4-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-05-05genirq: Fix type inconsistencyNicholas Mc Guire
The return type of kstat_irqs_usr() is unsigned int and kstat_irqs() also returns unsigned int so sum should be unsigned int here as well. Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Link: http://lkml.kernel.org/r/1430642951-23964-1-git-send-email-hofrat@osadl.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-05-05genirq: Fix unnecessary automatic type conversionNicholas Mc Guire
kstat_irqs is unsigned int and the return type of kstat_irqs() is also unsigned int so sum should be unsigned int as well even if the result is correct due to automatic type conversion. Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Link: http://lkml.kernel.org/r/1430642930-23929-1-git-send-email-hofrat@osadl.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-13genirq: Prevent proc race against freeing of irq descriptorsThomas Gleixner
Since the rework of the sparse interrupt code to actually free the unused interrupt descriptors there exists a race between the /proc interfaces to the irq subsystem and the code which frees the interrupt descriptor. CPU0 CPU1 show_interrupts() desc = irq_to_desc(X); free_desc(desc) remove_from_radix_tree(); kfree(desc); raw_spinlock_irq(&desc->lock); /proc/interrupts is the only interface which can actively corrupt kernel memory via the lock access. /proc/stat can only read from freed memory. Extremly hard to trigger, but possible. The interfaces in /proc/irq/N/ are not affected by this because the removal of the proc file is serialized in procfs against concurrent readers/writers. The removal happens before the descriptor is freed. For architectures which have CONFIG_SPARSE_IRQ=n this is a non issue as the descriptor is never freed. It's merely cleared out with the irq descriptor lock held. So any concurrent proc access will either see the old correct value or the cleared out ones. Protect the lookup and access to the irq descriptor in show_interrupts() with the sparse_irq_lock. Provide kstat_irqs_usr() which is protecting the lookup and access with sparse_irq_lock and switch /proc/stat to use it. Document the existing kstat_irqs interfaces so it's clear that the caller needs to take care about protection. The users of these interfaces are either not affected due to SPARSE_IRQ=n or already protected against removal. Fixes: 1f5a5b87f78f "genirq: Implement a sane sparse_irq allocator" Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org
2014-09-03genirq: Add irq_domain-aware core IRQ handlerMarc Zyngier
Calling irq_find_mapping from outside a irq_{enter,exit} section is unsafe and produces ugly messages if CONFIG_PROVE_RCU is enabled: If coming from the idle state, the rcu_read_lock call in irq_find_mapping will generate an unpleasant warning: <quote> =============================== [ INFO: suspicious RCU usage. ] 3.16.0-rc1+ #135 Not tainted ------------------------------- include/linux/rcupdate.h:871 rcu_read_lock() used illegally while idle! 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: (rcu_read_lock){......}, at: [<ffffffc00010206c>] irq_find_mapping+0x4c/0x198 </quote> As this issue is fairly widespread and involves at least three different architectures, a possible solution is to add a new handle_domain_irq entry point into the generic IRQ code that the interrupt controller code can call. This new function takes an irq_domain, and calls into irq_find_domain inside the irq_{enter,exit} block. An additional "lookup" parameter is used to allow non-domain architecture code to be replaced by this as well. Interrupt controllers can then be updated to use the new mechanism. This code is sitting behind a new CONFIG_HANDLE_DOMAIN_IRQ, as not all architectures implement set_irq_regs (yes, mn10300, I'm looking at you...). Reported-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Link: https://lkml.kernel.org/r/1409047421-27649-2-git-send-email-marc.zyngier@arm.com Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2014-07-05genirq: Fix memory leak when calling irq_free_hwirqs()Keith Busch
irq_free_hwirqs() always calls irq_free_descs() with a cnt == 0 which makes it a no-op since the interrupt count to free is decremented in itself. Fixes: 7b6ef1262549f6afc5c881aaef80beb8fd15f908 Signed-off-by: Keith Busch <keith.busch@intel.com> Acked-by: David Rientjes <rientjes@google.com> Link: http://lkml.kernel.org/r/1404167084-8070-1-git-send-email-keith.busch@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-05-16genirq: Remove dynamic_irq messThomas Gleixner
No more users. Get rid of the cruft. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Grant Likely <grant.likely@linaro.org> Tested-by: Tony Luck <tony.luck@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20140507154341.012847637@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-05-16genirq: Replace dynamic_irq_init/cleanupThomas Gleixner
Create a new interface and confine it with a config switch which makes clear that this is just legacy support and not to be used for new code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Grant Likely <grant.likely@linaro.org> Tested-by: Tony Luck <tony.luck@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20140507154340.574437049@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-05-16genirq: Remove irq_reserve_irq[s]Thomas Gleixner
No more users. And it's not going to come back. If you need hotplugable irq chips, use irq domains. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-and-acked-by: Grant Likely <grant.likely@linaro.org> Tested-by: Tony Luck <tony.luck@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20140507154340.302183048@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-05-16genirq: Replace reserve_irqs in core codeThomas Gleixner
We want to get rid of the public interface. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Grant Likely <grant.likely@linaro.org> Tested-by: Tony Luck <tony.luck@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20140507154340.061990194@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-05-16genirq: Provide generic hwirq allocation facilityThomas Gleixner
Not really the solution to the problem, but at least it confines the mess in the core code and allows to get rid of the create/destroy_irq variants from hell, i.e. 3 implementations with different semantics plus the x86 specific variants __create_irqs and create_irq_nr which have been invented in another circle of hell. x86 : x86 should be converted to irq domains and I'm deliberately making it impossible to do the multi-vector MSI support by adding more crap to the current mess. It's not that hard to do and I'm really tired of the trainwrecks which have been invented by baindaid engineering so far. Any attempt to do multi-vector MSI or ioapic hotplug without converting to irq domains is NAKed hereby. tile: Might use irq domains as well, but it has a very limited interrupt space, so handling it via this functionality might be the right thing to do even in the long run. ia64: That's an hopeless case, as I doubt that anyone has the stomach to rewrite the homebrewn dynamic allocation facilities. I stared at it for a couple of hours and gave up. The create/destroy_irq mess could be made private to itanic right away if there wouldn't be the iommu/dmar driver being shared with x86. So to do that I'm going to add a separate ia64 specific implementation later in order not to deep-six itanic right away. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Grant Likely <grant.likely@linaro.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: x86@kernel.org Link: http://lkml.kernel.org/r/20140507154334.208629358@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-04-28genirq: x86: Ensure that dynamic irq allocation does not conflictThomas Gleixner
On x86 the allocation of irq descriptors may allocate interrupts which are in the range of the GSI interrupts. That's wrong as those interrupts are hardwired and we don't have the irq domain translation like PPC. So one of these interrupts can be hooked up later to one of the devices which are hard wired to it and the io_apic init code for that particular interrupt line happily reuses that descriptor with a completely different configuration so hell breaks lose. Inside x86 we allocate dynamic interrupts from above nr_gsi_irqs, except for a few usage sites which have not yet blown up in our face for whatever reason. But for drivers which need an irq range, like the GPIO drivers, we have no limit in place and we don't want to expose such a detail to a driver. To cure this introduce a function which an architecture can implement to impose a lower bound on the dynamic interrupt allocations. Implement it for x86 and set the lower bound to nr_gsi_irqs, which is the end of the hardwired interrupt space, so all dynamic allocations happen above. That not only allows the GPIO driver to work sanely, it also protects the bogus callsites of create_irq_nr() in hpet, uv, irq_remapping and htirq code. They need to be cleaned up as well, but that's a separate issue. Reported-by: Jin Yao <yao.jin@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: Mathias Nyman <mathias.nyman@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Grant Likely <grant.likely@linaro.org> Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Krogerus Heikki <heikki.krogerus@intel.com> Cc: Linus Walleij <linus.walleij@linaro.org> Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1404241617360.28206@ionos.tec.linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-04genirq: Add a kstat helper to increment irq statsThomas Gleixner
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>
2014-02-11genirq: Add missing irq_to_desc export for CONFIG_SPARSE_IRQ=nPaul Gortmaker
In allmodconfig builds for sparc and any other arch which does not set CONFIG_SPARSE_IRQ, the following will be seen at modpost: CC [M] lib/cpu-notifier-error-inject.o CC [M] lib/pm-notifier-error-inject.o ERROR: "irq_to_desc" [drivers/gpio/gpio-mcp23s08.ko] undefined! make[2]: *** [__modpost] Error 1 This happens because commit 3911ff30f5 ("genirq: export handle_edge_irq() and irq_to_desc()") added one export for it, but there were actually two instances of it, in an if/else clause for CONFIG_SPARSE_IRQ. Add the second one. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: stable@vger.kernel.org # 3.4+ Link: http://lkml.kernel.org/r/1392057610-11514-1-git-send-email-paul.gortmaker@windriver.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-05-15genirq: export handle_edge_irq() and irq_to_desc()Jiri Kosina
Export handle_edge_irq() and irq_to_desc() to modules to allow them to do things such as __irq_set_handler_locked(...., handle_edge_irq); This fixes ERROR: "handle_edge_irq" [drivers/gpio/gpio-pch.ko] undefined! ERROR: "irq_to_desc" [drivers/gpio/gpio-pch.ko] undefined! when gpio-pch is being built as a module. This was introduced by commit df9541a60af0 ("gpio: pch9: Use proper flow type handlers") that added __irq_set_handler_locked(d->irq, handle_edge_irq); but handle_edge_irq() was not exported for modules (and inlined __irq_set_handler_locked() requires irq_to_desc() exported as well) Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31irq: don't put module.h into irq.h for tracking irqgen modules.Paul Gortmaker
Recent commit "irq: Track the owner of irq descriptor" in commit ID b6873807a7143b7 placed module.h into linux/irq.h but we are trying to limit module.h inclusion to just C files that really need it, due to its size and number of children includes. This targets just reversing that include. Add in the basic "struct module" since that is all we really need to ensure things compile. In theory, b687380 should have added the module.h include to the irqdesc.h header as well, but the implicit module.h everywhere presence masked this from showing up. So give it the "struct module" as well. As for the C files, irqdesc.c is only using THIS_MODULE, so it does not need module.h - give it export.h instead. The C file irq/manage.c is now (as of b687380) using try_module_get and module_put and so it needs module.h (which it already has). Also convert the irq_alloc_descs variants to macros, since all they really do is is call the __irq_alloc_descs primitive. This avoids including export.h and no debug info is lost. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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>
2011-08-18irqdesc: fix new kernel-doc warningRandy Dunlap
Fix kernel-doc warning in irqdesc.c: Warning(kernel/irq/irqdesc.c:353): No description found for parameter 'owner' Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-28irq: Track the owner of irq descriptorSebastian Andrzej Siewior
Interrupt descriptors can be allocated from modules. The interrupts are used by other modules, but we have no refcount on the module which provides the interrupts and there is no way to establish one on the device level as the interrupt using module is agnostic to the fact that the interrupt is provided by a module rather than by some builtin interrupt controller. To prevent removal of the interrupt providing module, we can track the owner of the interrupt descriptor, which also provides the relevant irq chip functions in the irq descriptor. request/setup_irq() can now acquire a refcount on the owner module to prevent unloading. free_irq() drops the refcount. Signed-off-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc> Link: http://lkml.kernel.org/r/20110711101731.GA13804@Chamillionaire.breakpoint.cc Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-06-03genirq: Ensure we locate the passed IRQ in irq_alloc_descs()Mark Brown
When irq_alloc_descs() is called with no base IRQ specified then it will search for a range of IRQs starting from a specified base address. In the case where an IRQ is specified it still does this search in order to ensure that none of the requested range is already allocated and it still uses the from parameter to specify the base for the search. This means that in the case where a base is specified but from is zero (which is reasonable as any IRQ number is in the range specified by a zero from) the function will get confused and try to allocate the first suitably sized block of free IRQs it finds. Instead use a specified IRQ as the base address for the search, and insist that any from that is specified can support that IRQ. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Link: http://lkml.kernel.org/r/1307037313-15733-1-git-send-email-broonie@opensource.wolfsonmicro.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-06-03genirq: Fix descriptor init on non-sparse IRQsLinus Walleij
The genirq changes are initializing descriptors for sparse IRQs quite differently from how non-sparse (stacked?) IRQs are initialized, with the effect that on my platform all IRQs are default-disabled on sparse IRQs and default-enabled if non-sparse IRQs are used, crashing some GPIO driver. Fix this by refactoring the non-sparse IRQs to use the same descriptor init function as the sparse IRQs. Signed-off: Linus Walleij <linus.walleij@linaro.org> Link: http://lkml.kernel.org/r/1306858479-16622-1-git-send-email-linus.walleij@stericsson.com Cc: stable@kernel.org # 2.6.39 Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-05-18irq: Export functions to allow modular irq driversJonathan Cameron
Export handle_simple_irq, irq_modify_status, irq_alloc_descs, irq_free_descs and generic_handle_irq to allow their usage in modules. First user is IIO, which wants to be built modular, but needs to be able to create irq chips, allocate and configure interrupt descriptors and handle demultiplexing interrupts. [ tglx: Moved the uninlinig of generic_handle_irq to a separate patch ] Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk> Link: http://lkml.kernel.org/r/%3C1305711544-505-1-git-send-email-jic23%40cam.ac.uk%3E Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-05-18genirq: Uninline and sanity check generic_handle_irq()Thomas Gleixner
generic_handle_irq() is missing a NULL pointer check for the result of irq_to_desc. This was a not a big problem, but we want to expose it to drivers, so we better have sanity checks in place. Add a return value as well, which indicates that the irq number was valid and the handler was invoked. Based on the pure code move from Jonathan Cameron. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jonathan Cameron <jic23@cam.ac.uk>
2011-05-18genirq: Remove pointless ifdefsThomas Gleixner
kernel/irq/ is only built when CONFIG_GENERIC_HARDIRQS=y. So making code inside of kernel/irq/ conditional on CONFIG_GENERIC_HARDIRQS is pointless. 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>
2011-03-27genirq: Add irq disabled flag to irq_data stateThomas Gleixner
Some irq_chip implementation require to know the disabled state of the interrupt in certain callbacks. Add a state flag and accessor to irq_data. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-03-23genirq; Remove the last leftovers of the old sparse irq codeThomas Gleixner
All users converted. Get rid of it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-21genirq: Use IRQ_BITMAP_BITS as search size in irq_alloc_descs()Yinghai Lu
The runtime expansion of nr_irqs does not take into account that bitmap_find_next_zero_area() returns "start" + size in case the search for an matching zero area fails. That results in a start value which can be completely off and is not covered by the following expand_nr_irqs() and possibly outside of the absolute limit. But we use it without further checking. Use IRQ_BITMAP_BITS as the limit for the bitmap search and expand nr_irqs when the start bit is beyond nr_irqs. So start is always pointing to the correct area in the bitmap. nr_irqs is just the limit for irq enumerations, not the real limit for the irq space. [ tglx: Let irq_expand_nr_irqs() take the new upper end so we do not expand nr_irqs more than necessary. Made changelog readable ] Signed-off-by: Yinghai Lu <yinghai@kernel.org> LKML-Reference: <4D6014F9.8040605@kernel.org> Signed-off-by: Thomas Gleixner <tglx@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: Force wrapped access to desc->status in core codeThomas Gleixner
Force the usage of wrappers by another nasty CPP substitution. 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: 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: Make nr_irqs runtime expandableThomas Gleixner
We face more and more the requirement to expand nr_irqs at runtime. The reason are irq expanders which can not be detected in the early boot stage. So we speculate nr_irqs to have enough room. Further Xen needs extra irq numbers and we really want to avoid adding more "detection" code into the early boot. There is no real good reason why we need to limit nr_irqs at early boot. Allow the allocation code to expand nr_irqs. We have already 8k extra number space in the allocation bitmap, so lets use it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19Merge branch 'irq/urgent' into irq/coreThomas Gleixner
Reason: Further patches are conflicting with mainline fixes 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>
2011-02-08genirq: Remove dead codeThomas Gleixner
CONFIG_KSTAT_IRQS_ONDEMAND does not exist. It's not worth to implement it. Use sparse irqs if you care about memory consumption of the interrupt layer. Found by undertaker: http://vamos.informatik.uni-erlangen.de/trac/undertaker Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-01-13irq: use per_cpu kstat_irqsEric Dumazet
Use modern per_cpu API to increment {soft|hard}irq counters, and use per_cpu allocation for (struct irq_desc)->kstats_irq instead of an array. This gives better SMP/NUMA locality and saves few instructions per irq. With small nr_cpuids values (8 for example), kstats_irq was a small array (less than L1_CACHE_BYTES), potentially source of false sharing. In the !CONFIG_SPARSE_IRQ case, remove the huge, NUMA/cache unfriendly kstat_irqs_all[NR_IRQS][NR_CPUS] array. Note: we still populate kstats_irq for all possible irqs in early_irq_init(). We probably could use on-demand allocations. (Code included in alloc_descs()). Problem is not all IRQS are used with a prior alloc_descs() call. kstat_irqs_this_cpu() is not used anymore, remove it. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Reviewed-by: Christoph Lameter <cl@linux.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andi Kleen <andi@firstfloor.org> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-27/proc/stat: fix scalability of irq sum of all cpuKAMEZAWA Hiroyuki
In /proc/stat, the number of per-IRQ event is shown by making a sum each irq's events on all cpus. But we can make use of kstat_irqs(). kstat_irqs() do the same calculation, If !CONFIG_GENERIC_HARDIRQ, it's not a big cost. (Both of the number of cpus and irqs are small.) If a system is very big and CONFIG_GENERIC_HARDIRQ, it does for_each_irq() for_each_cpu() - look up a radix tree - read desc->irq_stat[cpu] This seems not efficient. This patch adds kstat_irqs() for CONFIG_GENRIC_HARDIRQ and change the calculation as for_each_irq() look up radix tree for_each_cpu() - read desc->irq_stat[cpu] This reduces cost. A test on (4096cpusp, 256 nodes, 4592 irqs) host (by Jack Steiner) %time cat /proc/stat > /dev/null Before Patch: 2.459 sec After Patch : .561 sec [akpm@linux-foundation.org: unexport kstat_irqs, coding-style tweaks] [akpm@linux-foundation.org: fix unused variable 'per_irq_sum'] Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Tested-by: Jack Steiner <steiner@sgi.com> Acked-by: Jack Steiner <steiner@sgi.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-12genirq: Fix CONFIG_GENIRQ_NO_DEPRECATED=y buildThomas Gleixner
This option can be set to verify the full conversion to the new chip functions. Fix the fallout of the patch rework, so the core code compiles and works with it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-10-12genirq: Switch sparse_irq allocator to GFP_KERNELThomas Gleixner
The allocator functions are now called outside of preempt disabled regions. Switch to GFP_KERNEL. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-10-12genirq: Make sparse_lock a mutexThomas Gleixner
No callers from atomic regions. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@elte.hu>
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: Remove arch_init_chip_data()Thomas Gleixner
This function should have not been there in the first place. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-10-12genirq: Query arch for number of early descriptorsThomas Gleixner
sparse irq sets up NR_IRQS_LEGACY irq descriptors and archs then go ahead and allocate more. Use the unused return value of arch_probe_nr_irqs() to let the architecture return the number of early allocations. Fix up all users. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-10-12genirq: Use sane sparse allocatorThomas Gleixner
Make irq_to_desc_alloc_node() a wrapper around the new allocator. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-10-12genirq: Implement irq reservationThomas Gleixner
Mark a range of interrupts as allocated. In the SPARSE_IRQ=n case we need this to update the bitmap for the legacy irqs so the enumerator via irq_get_next_irq() works. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-10-12genirq: Implement sane enumerationThomas Gleixner
Use the allocator bitmap to lookup active interrupts. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@elte.hu>