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path: root/kernel/irq/handle.c
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2009-04-01Merge branch 'tracing/core-v2' into tracing-for-linusIngo Molnar
Conflicts: include/linux/slub_def.h lib/Kconfig.debug mm/slob.c mm/slub.c
2009-03-27Merge branch 'core/percpu' into percpu-cpumask-x86-for-linus-2Ingo Molnar
Conflicts: arch/parisc/kernel/irq.c arch/x86/include/asm/fixmap_64.h arch/x86/include/asm/setup.h kernel/irq/handle.c Semantic merge: arch/x86/include/asm/fixmap.h Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-16Merge branches 'irq/genirq' and 'linus' into irq/coreIngo Molnar
2009-03-13genirq: deprecate __do_IRQThomas Gleixner
Two years migration time is enough. Remove the compability cruft. Add the deprecated warning in kernel/irq/handle.c because marking __do_IRQ itself is way too noisy. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-03-06Merge branch 'x86/core' into tracing/texteditIngo Molnar
Conflicts: arch/x86/Kconfig block/blktrace.c kernel/irq/handle.c Semantic conflict: kernel/trace/blktrace.c Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-02genirq: assert that irq handlers are indeed running in hardirq contextPeter Zijlstra
Make sure the genirq layer handlers are indeed running handlers in hardirq context. That is the genirq expectation and doing anything else is broken. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Andrew Morton <akpm@linux-foundation.org> LKML-Reference: <1236006812.5330.632.camel@laptop> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-26tracing, genirq: add irq enter and exit trace eventsJason Baron
Impact: add new tracepoints Add them to the generic IRQ code, that way every architecture gets these new tracepoints, not just x86. Using Steve's new 'TRACE_FORMAT', I can get function graph trace as follows using the original two IRQ tracepoints: 3) | handle_IRQ_event() { 3) | /* (irq_handler_entry) irq=28 handler=eth0 */ 3) | e1000_intr_msi() { 3) 2.460 us | __napi_schedule(); 3) 9.416 us | } 3) | /* (irq_handler_exit) irq=28 handler=eth0 return=handled */ 3) + 22.935 us | } Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Mathieu Desnoyers <compudj@krystal.dyndns.org> Cc: "Frank Ch. Eigler" <fche@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-13Merge branches 'irq/genirq', 'irq/sparseirq' and 'irq/urgent' into irq/coreIngo Molnar
2009-02-09irq: optimize init_kstat_irqs/init_copy_kstat_irqsYinghai Lu
Simplify and make init_kstat_irqs etc more type proof, suggested by Andrew. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-09irq: clear kstat_irqsYinghai Lu
Impact: get correct kstat_irqs [/proc/interrupts] for msi/msi-x etc need to call clear_kstat_irqs(), so when we reuse that irq_desc, we get correct kstat in /proc/interrupts. This makes /proc/interrupts not have <NULL> entries. Don't need to worry about arch that doesn't support genirq, because they will not call dynamic_irq_cleanup(). v2: simplify and make clear_kstat_irqs more robust Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-30Merge branch 'linus' into core/percpuIngo Molnar
Conflicts: kernel/irq/handle.c
2009-01-28cpumask fallout: Initialize irq_default_affinity earlierDavid Daney
Move the initialization of irq_default_affinity to early_irq_init as core_initcall is too late. irq_default_affinity can be used in init_IRQ and potentially timer and SMP init as well. All of these happen before core_initcall. Moving the initialization to early_irq_init ensures that it is initialized before it is used. Signed-off-by: David Daney <ddaney@caviumnetworks.com> Acked-by: Mike Travis <travis@sgi.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-13x86: arch_probe_nr_irqsYinghai Lu
Impact: save RAM with large NR_CPUS, get smaller nr_irqs Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Mike Travis <travis@sgi.com>
2009-01-11cpumask, irq: non-x86 build failuresMike Travis
Ingo Molnar wrote: > All non-x86 architectures fail to build: > > In file included from /home/mingo/tip/include/linux/random.h:11, > from /home/mingo/tip/include/linux/stackprotector.h:6, > from /home/mingo/tip/init/main.c:17: > /home/mingo/tip/include/linux/irqnr.h:26:63: error: asm/irq_vectors.h: No such file or directory Do not include asm/irq_vectors.h in generic code - it's not available on all architectures. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-11kstat: modify kstat_irqs_legacy to be variable sizedMike Travis
Impact: reduce memory usage. Allocate kstat_irqs_legacy based on nr_cpu_ids to deal with this memory usage bump when NR_CPUS bumped from 128 to 4096: 8192 +253952 262144 +3100% kstat_irqs_legacy(.bss) This is only when CONFIG_SPARSE_IRQS=y. Signed-off-by: Mike Travis <travis@sgi.com>
2009-01-11irq: initialize nr_irqs based on nr_cpu_idsMike Travis
Impact: Reduce memory usage. This is the second half of the changes to make the irq_desc_ptrs be variable sized based on nr_cpu_ids. This is done by adding a new "max_nr_irqs" macro to irq_vectors.h (and a dummy in irqnr.h) to return a max NR_IRQS value based on NR_CPUS or nr_cpu_ids. This necessitated moving the define of MAX_IO_APICS to a separate file (asm/apicnum.h) so it could be included without the baggage of the other asm/apicdef.h declarations. Signed-off-by: Mike Travis <travis@sgi.com>
2009-01-11irq: allocate irq_desc_ptrs array based on nr_irqsMike Travis
Impact: allocate irq_desc_ptrs in preparation for making it variable-sized. This addresses this memory usage bump when NR_CPUS bumped from 128 to 4096: 34816 +229376 264192 +658% irq_desc_ptrs(.data.read_mostly) The patch is split into two parts, the first simply allocates the irq_desc_ptrs array. Then next will deal with making it variable. This is only when CONFIG_SPARSE_IRQS=y. Signed-off-by: Mike Travis <travis@sgi.com>
2009-01-11irq: use WARN() instead of WARN_ON().Mike Travis
Impact: cleanup WARN msg. Ingo requested: > While at it, could you please also convert this to a WARN() construct > instead? (in a separate commit) ... and it shall be done. ;-) Signed-off-by: Mike Travis <travis@sgi.com>
2009-01-11irq: change references from NR_IRQS to nr_irqsMike Travis
Impact: preparation, cleanup, add KERN_INFO printk Modify references from NR_IRQS to nr_irqs as the later will become variable-sized based on nr_cpu_ids when CONFIG_SPARSE_IRQS=y. Signed-off-by: Mike Travis <travis@sgi.com>
2009-01-11cpumask: fix bug in use cpumask_var_t in irq_descMike Travis
Impact: fix bug where new irq_desc uses old cpumask pointers which are freed. As Yinghai pointed out, init_copy_one_irq_desc() copies the old desc to the new desc overwriting the cpumask pointers. Since the old_desc and the cpumask pointers are freed, then memory corruption will occur if these old pointers are used. Move the allocation of these pointers to after the copy. Signed-off-by: Mike Travis <travis@sgi.com> Cc: Yinghai Lu <yinghai@kernel.org>
2009-01-11cpumask: update irq_desc to use cpumask_var_tMike Travis
Impact: reduce memory usage, use new cpumask API. Replace the affinity and pending_masks with cpumask_var_t's. This adds to the significant size reduction done with the SPARSE_IRQS changes. The added functions (init_alloc_desc_masks & init_copy_desc_masks) are in the include file so they can be inlined (and optimized out for the !CONFIG_CPUMASKS_OFFSTACK case.) [Naming chosen to be consistent with the other init*irq functions, as well as the backwards arg declaration of "from, to" instead of the more common "to, from" standard.] Includes a slight change to the declaration of struct irq_desc to embed the pending_mask within ifdef(CONFIG_SMP) to be consistent with other references, and some small changes to Xen. Tested: sparse/non-sparse/cpumask_offstack/non-cpumask_offstack/nonuma/nosmp on x86_64 Signed-off-by: Mike Travis <travis@sgi.com> Cc: Chris Wright <chrisw@sous-sol.org> Cc: Jeremy Fitzhardinge <jeremy@xensource.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Cc: virtualization@lists.osdl.org Cc: xen-devel@lists.xensource.com Cc: Yinghai Lu <yhlu.kernel@gmail.com>
2009-01-11sparseirq: make some func to be used with genirqYinghai Lu
Impact: clean up sparseirq fallout on random.c Ingo suggested to change some ifdef from SPARSE_IRQ to GENERIC_HARDIRQS so we could some #ifdef later if all arch support genirq Signed-off-by: Yinghai Lu <yinghai@kernel.org> Acked-by: Matt Mackall <mpm@selenic.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-28sparseirq: work around __weak alias bugIngo Molnar
Impact: fix boot crash if the kernel is built with certain GCC versions GCC has a bug with __weak alias functions: if the functions are in the same compilation unit as their call site, GCC can decide to inline them - and thus rob the linker of the opportunity to override the weak alias with the real thing. This can lead to the boot crash reported by Kamalesh Babulal: ACPI: Core revision 20080926 Setting APIC routing to flat BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 IP: [<ffffffff8021f9a8>] add_pin_to_irq_cpu+0x14/0x74 PGD 0 Oops: 0000 [#1] SMP [...] So move the arch_init_chip_data() function from handle.c to manage.c. Reported-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-27sparseirq: fix hang with !SPARSE_IRQYinghai Lu
Impact: fix hang Suresh report his two sockets system only works with SPARSE_IRQ enable it turns out we miss the setting desc->irq so provide early_irq_init() even !SPARSE_IRQ to set desc->irq Reported-by: "Siddha, Suresh B" <suresh.b.siddha@intel.com> Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-27sparseirq: set lock_class for legacy irq when sparse_irq is selectedYinghai Lu
Impact: add lockdep annotation to legacy IRQ descs Warnings resulting out of this were not seen in practice, but it's prudent to initialize the legacy descriptors to the lock class as well, symmetric to how we do it with other descriptors. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-27sparseirq: work around compiler optimizing away __weak functionsYinghai Lu
Impact: fix panic on null pointer with sparseirq Some GCC versions seem to inline the weak global function, when that function is empty. Work it around, by making the functions return a (dummy) integer. Signed-off-by: Yinghai <yinghai@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-27sparseirq: fix desc->lock initIngo Molnar
Impact: cleanup init_one_irq_desc() does not initialize the desc->lock properly - you cannot init a lock by memcpying some other lock on it. This happens to work right now (because irq_desc_init is never in use), but it's a dangerous construct nevertheless, so fix it. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-26sparseirq: remove duplicated arch_early_irq_init()Yinghai Lu
Impact: clean up We already have a weak copy of this function in init/main.c Signed-off-by: Yinghai <yinghai@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-26irq: simplify for_each_irq_desc() usageKOSAKI Motohiro
Impact: cleanup all for_each_irq_desc() usage point have !desc check. then its check can move into for_each_irq_desc() macro. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-26proc: remove ifdef CONFIG_SPARSE_IRQ from stat.cKOSAKI Motohiro
Impact: cleanup irq_desc can be NULL when CONFIG_SPARSE_IRQ=y only. therefore, NULL checking can move into kstat_irqs_cpu() of SPARSE_IRQ version. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: "Yinghai Lu" <yinghai@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-26irq: for_each_irq_desc() move to irqnr.hKOSAKI Motohiro
Impact: cleanup before CONFIG_SPARSE_IRQ age, for_each_irq_desc() sat in irqnr.h and could be called from generic code. CONFIG_SPARSE_IRQ breaks this assumption, but SPARSE_IRQ version for_each_irq_desc() also can move into irqnr.h easily. Also, this patch unifies CONFIG_SPARSE_IRQ and !CONFIG_SPARSE_IRQ for_each_irq_desc(). Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-18locking, irq: enclose irq_desc_lock_class in CONFIG_LOCKDEPKOSAKI Motohiro
Impact: simplify code commit "08678b0: generic: sparse irqs: use irq_desc() [...]" introduced the irq_desc_lock_class variable. But it is used only if CONFIG_SPARSE_IRQ=Y or CONFIG_TRACE_IRQFLAGS=Y. Otherwise, following warnings happen: CC kernel/irq/handle.o kernel/irq/handle.c:26: warning: 'irq_desc_lock_class' defined but not used Actually, current early_init_irq_lock_class has a bit strange and messy ifdef. In addition, it is not valueable. 1. this function is protected by !CONFIG_SPARSE_IRQ, but that is not necessary. if CONFIG_SPARSE_IRQ=Y, desc of all irq number are initialized by NULL at first - then this function calling is safe. 2. this function protected by CONFIG_TRACE_IRQFLAGS too. but it is not necessary either, because lockdep_set_class() doesn't have bad side effect even if CONFIG_TRACE_IRQFLAGS=n. This patch bloat kernel size a bit on CONFIG_TRACE_IRQFLAGS=n and CONFIG_SPARSE_IRQ=Y - but that's ok. early_init_irq_lock_class() is not a fastpatch at all. To avoid messy ifdefs is more important than a few bytes diet. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-16x86, sparseirq: move irq_desc according to smp_affinity, v7Yinghai Lu
Impact: improve NUMA handling by migrating irq_desc on smp_affinity changes if CONFIG_NUMA_MIGRATE_IRQ_DESC is set: - make irq_desc to go with affinity aka irq_desc moving etc - call move_irq_desc in irq_complete_move() - legacy irq_desc is not moved, because they are allocated via static array for logical apic mode, need to add move_desc_in_progress_in_same_domain, otherwise it will not be moved ==> also could need two phases to get irq_desc moved. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-08x86: use NR_IRQS_LEGACYYinghai Lu
Impact: cleanup Introduce NR_IRQS_LEGACY instead of hard coded number. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-08sparse irq_desc[] array: core kernel and x86 changesYinghai Lu
Impact: new feature Problem on distro kernels: irq_desc[NR_IRQS] takes megabytes of RAM with NR_CPUS set to large values. The goal is to be able to scale up to much larger NR_IRQS value without impacting the (important) common case. To solve this, we generalize irq_desc[NR_IRQS] to an (optional) array of irq_desc pointers. When CONFIG_SPARSE_IRQ=y is used, we use kzalloc_node to get irq_desc, this also makes the IRQ descriptors NUMA-local (to the site that calls request_irq()). This gets rid of the irq_cfg[] static array on x86 as well: irq_cfg now uses desc->chip_data for x86 to store irq_cfg. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-16genirq: use iterators for irq_desc loopsThomas Gleixner
Use for_each_irq_desc[_reverse] for all the iteration loops. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-10-16genirq: cleanup the sparseirq modificationsThomas Gleixner
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-10-16genirq: revert dynarrayThomas Gleixner
Revert the dynarray changes. They need more thought and polishing. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-10-16genirq: remove sparse irq codeThomas Gleixner
This code is not ready, but we need to rip it out instead of rebasing as we would lose the APIC/IO_APIC unification otherwise. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-10-16genirq: use inline function for irq_to_descThomas Gleixner
For the non sparse irq case an inline function is perfectly fine. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-10-16x86: fix typo in irq_desc arrayYinghai Lu
when SPARSE_IRQ is not used, should still use irq_desc->lock Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-16fix warning: "x86: sparse_irq needs spin_lock in allocations"Andrew Morton
caused by commit a532e19680ada3b8579b81e67e76d3ebd19c340f Author: Yinghai Lu <yhlu.kernel@gmail.com> Date: Wed Aug 20 20:46:25 2008 -0700 x86: sparse_irq needs spin_lock in allocations Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-16sparseirq: remove some debug print outYinghai Lu
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-16sparseirq: move kstat_irqs from kstat to irq_desc - fixYinghai Lu
fix non-sparseirq architectures. Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-16x86: sparse_irq needs spin_lock in allocationsYinghai Lu
Suresh Siddha noticed that we should have a spinlock around it. Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-16sparseirq: fix lockdepIngo Molnar
-tip testing found this lockdep splat: [ 0.000000] Initializing CPU#0 [ 0.000000] found new irq_desc for irq 0 [ 0.000000] INFO: trying to register non-static key. [ 0.000000] the code is fine but needs lockdep annotation. [ 0.000000] turning off the locking correctness validator. [ 0.000000] Pid: 0, comm: swapper Not tainted 2.6.27-rc3-tip-00191-g98ccb89-dirty #1 [ 0.000000] [<c0153c22>] register_lock_class+0x3d2/0x400 [ 0.000000] [<c0104d87>] ? mcount_call+0x5/0xa [ 0.000000] [<c0154f3a>] __lock_acquire+0x22a/0x5d0 [ 0.000000] [<c0104d87>] ? mcount_call+0x5/0xa [ 0.000000] [<c0155351>] lock_acquire+0x71/0xa0 [ 0.000000] [<c016d61f>] ? set_irq_chip+0x3f/0x90 [ 0.000000] [<c070f148>] _spin_lock_irqsave+0x58/0x90 [ 0.000000] [<c016d61f>] ? set_irq_chip+0x3f/0x90 [ 0.000000] [<c016d61f>] set_irq_chip+0x3f/0x90 [ 0.000000] [<c016d7e0>] ? handle_level_irq+0x0/0xe0 [ 0.000000] [<c016da1a>] set_irq_chip_and_handler_name+0x1a/0x40 [ 0.000000] [<c0a396c1>] init_ISA_irqs+0x51/0xa0 [ 0.000000] [<c0a4a365>] pre_intr_init_hook+0x25/0x30 [ 0.000000] [<c0a39723>] native_init_IRQ+0x13/0x370 [ 0.000000] [<c015569c>] ? lock_release+0xcc/0x1d0 [ 0.000000] [<c0104d87>] ? mcount_call+0x5/0xa [ 0.000000] [<c070dc22>] ? __mutex_unlock_slowpath+0x92/0x110 [ 0.000000] [<c070dcad>] ? mutex_unlock+0xd/0x10 [ 0.000000] [<c0135f62>] ? cpu_maps_update_done+0x12/0x20 [ 0.000000] [<c06c6743>] ? register_cpu_notifier+0x23/0x30 [ 0.000000] [<c011e8ae>] init_IRQ+0xe/0x10 [ 0.000000] [<c0a357a5>] start_kernel+0x1c5/0x340 [ 0.000000] [<c0a35280>] ? unknown_bootoption+0x0/0x210 [ 0.000000] [<c0a3506b>] i386_start_kernel+0x6b/0x80 [ 0.000000] ======================= [ 0.000000] found new irq_desc for irq 1 [ 0.000000] found new irq_desc for irq 2 [ 0.000000] found new irq_desc for irq 3 this: static void init_one_irq_desc(struct irq_desc *desc) { memcpy(desc, &irq_desc_init, sizeof(struct irq_desc)); #ifdef CONFIG_TRACE_IRQFLAGS lockdep_set_class(&desc->lock, &irq_desc_lock_class); #endif } should be unconditional. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-16irq: separate sparse_irqs from sparse_irqs_freeYinghai Lu
so later don't need compare with -1U Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-16x86_64: rename irq_desc/irq_desc_allocYinghai Lu
change names: irq_desc() ==> irq_desc_alloc __irq_desc() ==> irq_desc Also split a few of the uses in lowlevel x86 code. v2: need to check if desc is null in smp_irq_move_cleanup Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-16generic: add irq_desc in function in parameterYinghai Lu
So we could remove some duplicated calling to irq_desc v2: make sure irq_desc in init/main.c is not used without generic_hardirqs Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-16irq: add irq_desc_without_newYinghai Lu
add an irq_desc accessor that will not allocate any sparse entry but returns failure if there's no entry present. Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>