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2013-06-28genirq: Fix can_request_irq() for IRQs without an actionBen Hutchings
Commit 02725e7471b8 ('genirq: Use irq_get/put functions'), inadvertently changed can_request_irq() to return 0 for IRQs that have no action. This causes pcibios_lookup_irq() to select only IRQs that already have an action with IRQF_SHARED set, or to fail if there are none. Change can_request_irq() to return 1 for IRQs that have no action (if the first two conditions are met). Reported-by: Bjarni Ingi Gislason <bjarniig@rhi.hi.is> Tested-by: Bjarni Ingi Gislason <bjarniig@rhi.hi.is> (against 3.2) Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: 709647@bugs.debian.org Cc: stable@vger.kernel.org # 2.6.39+ Link: http://bugs.debian.org/709647 Link: http://lkml.kernel.org/r/1372383630.23847.40.camel@deadeye.wl.decadent.org.uk Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-06-11genirq: Set irq thread to RT priority on creationIvo Sieben
When a threaded irq handler is installed the irq thread is initially created on normal scheduling priority. Only after the irq thread is woken up it sets its priority to RT_FIFO MAX_USER_RT_PRIO/2 itself. This means that interrupts that occur directly after the irq handler is installed will be handled on a normal scheduling priority instead of the realtime priority that one would expect. Fix this by setting the RT priority on creation of the irq_thread. Signed-off-by: Ivo Sieben <meltedpianoman@gmail.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1370254322-17240-1-git-send-email-meltedpianoman@gmail.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-02-20Merge branch 'sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler changes from Ingo Molnar: "Main changes: - scheduler side full-dynticks (user-space execution is undisturbed and receives no timer IRQs) preparation changes that convert the cputime accounting code to be full-dynticks ready, from Frederic Weisbecker. - Initial sched.h split-up changes, by Clark Williams - select_idle_sibling() performance improvement by Mike Galbraith: " 1 tbench pair (worst case) in a 10 core + SMT package: pre 15.22 MB/sec 1 procs post 252.01 MB/sec 1 procs " - sched_rr_get_interval() ABI fix/change. We think this detail is not used by apps (so it's not an ABI in practice), but lets keep it under observation. - misc RT scheduling cleanups, optimizations" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) sched/rt: Add <linux/sched/rt.h> header to <linux/init_task.h> cputime: Remove irqsave from seqlock readers sched, powerpc: Fix sched.h split-up build failure cputime: Restore CPU_ACCOUNTING config defaults for PPC64 sched/rt: Move rt specific bits into new header file sched/rt: Add a tuning knob to allow changing SCHED_RR timeslice sched: Move sched.h sysctl bits into separate header sched: Fix signedness bug in yield_to() sched: Fix select_idle_sibling() bouncing cow syndrome sched/rt: Further simplify pick_rt_task() sched/rt: Do not account zero delta_exec in update_curr_rt() cputime: Safely read cputime of full dynticks CPUs kvm: Prepare to add generic guest entry/exit callbacks cputime: Use accessors to read task cputime stats cputime: Allow dynamic switch between tick/virtual based cputime accounting cputime: Generic on-demand virtual cputime accounting cputime: Move default nsecs_to_cputime() to jiffies based cputime file cputime: Librarize per nsecs resolution cputime definitions cputime: Avoid multiplication overflow on utime scaling context_tracking: Export context state for generic vtime ... Fix up conflict in kernel/context_tracking.c due to comment additions.
2013-02-18genirq: Export enable/disable_percpu_irq()Chris Metcalf
These functions are used by the tilegx onchip network driver, and it's useful to be able to load that driver as a module. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> Link: http://lkml.kernel.org/r/201302012043.r11KhNZF024371@farm-0021.internal.tilera.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-02-07sched/rt: Move rt specific bits into new header fileClark Williams
Move rt scheduler definitions out of include/linux/sched.h into new file include/linux/sched/rt.h Signed-off-by: Clark Williams <williams@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20130207094707.7b9f825f@riff.lan Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-12-18irq: tsk->comm is an arrayAlan Cox
The array check is useless so remove it. [akpm@linux-foundation.org: remove comment, per David] Signed-off-by: Alan Cox <alan@linux.intel.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-11-12genirq: Always force thread affinityThomas Gleixner
Sankara reported that the genirq core code fails to adjust the affinity of an interrupt thread in several cases: 1) On request/setup_irq() the call to setup_affinity() happens before the new action is registered, so the new thread is not notified. 2) For secondary shared interrupts nothing notifies the new thread to change its affinity. 3) Interrupts which have the IRQ_NO_BALANCE flag set are not moving the thread either. Fix this by setting the thread affinity flag right on thread creation time. This ensures that under all circumstances the thread moves to the right place. Requires a check in irq_thread_check_affinity for an existing affinity mask (CONFIG_CPU_MASK_OFFSTACK=y) Reported-and-tested-by: Sankara Muthukrishnan <sankara.m@gmail.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1209041738200.2754@ionos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-11-01irq: Set CPU affinity right on thread creationSankara Muthukrishnan
As irq_thread_check_affinity is called ONLY inside the while loop in the irq thread, the core affinity is set only when an interrupt occurs. This patch sets the core affinity right after the irq thread is created and before it waits for interrupts. In real-tiime targets that do not typically change the core affinity of irqs during run-time, this patch will save additional latency of an irq thread in setting the core affinity during the first interrupt occurrence for that irq. Signed-off-by: Sankara S Muthukrishnan <sankara.m@ni.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/CAFQPvXeVZ858WFYimEU5uvLNxLDd6bJMmqWihFmbCf3ntokz0A@mail.gmail.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-11-01genirq: Provide means to retrigger parentThomas Gleixner
Attempts to retrigger nested threaded IRQs currently fail because they have no primary handler. In order to support retrigger of nested IRQs, the parent IRQ needs to be retriggered. To fix, when an IRQ needs to be resent, if the interrupt has a parent IRQ and runs in the context of the parent IRQ, then resend the parent. Also, handle_nested_irq() needs to clear the replay flag like the other handlers, otherwise check_irq_resend() will set it and it will never be cleared. Without clearing, it results in the first resend working fine, but check_irq_resend() returning early on subsequent resends because the replay flag is still set. Problem discovered on ARM/OMAP platforms where a nested IRQ that's also a wakeup IRQ happens late in suspend and needed to be retriggered during the resume process. [khilman@ti.com: changelog edits, clear IRQS_REPLAY in handle_nested_irq()] Reported-by: Kevin Hilman <khilman@ti.com> Tested-by: Kevin Hilman <khilman@ti.com> Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1350425269-11489-1-git-send-email-khilman@deeprootsystems.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-08-03Merge branch 'irq-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fix from Ingo Molnar. * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq: Allow irq chips to mark themself oneshot safe
2012-08-01Merge tag 'random_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random Pull random subsystem patches from Ted Ts'o: "This patch series contains a major revamp of how we collect entropy from interrupts for /dev/random and /dev/urandom. The goal is to addresses weaknesses discussed in the paper "Mining your Ps and Qs: Detection of Widespread Weak Keys in Network Devices", by Nadia Heninger, Zakir Durumeric, Eric Wustrow, J. Alex Halderman, which will be published in the Proceedings of the 21st Usenix Security Symposium, August 2012. (See https://factorable.net for more information and an extended version of the paper.)" Fix up trivial conflicts due to nearby changes in drivers/{mfd/ab3100-core.c, usb/gadget/omap_udc.c} * tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random: (33 commits) random: mix in architectural randomness in extract_buf() dmi: Feed DMI table to /dev/random driver random: Add comment to random_initialize() random: final removal of IRQF_SAMPLE_RANDOM um: remove IRQF_SAMPLE_RANDOM which is now a no-op sparc/ldc: remove IRQF_SAMPLE_RANDOM which is now a no-op [ARM] pxa: remove IRQF_SAMPLE_RANDOM which is now a no-op board-palmz71: remove IRQF_SAMPLE_RANDOM which is now a no-op isp1301_omap: remove IRQF_SAMPLE_RANDOM which is now a no-op pxa25x_udc: remove IRQF_SAMPLE_RANDOM which is now a no-op omap_udc: remove IRQF_SAMPLE_RANDOM which is now a no-op goku_udc: remove IRQF_SAMPLE_RANDOM which was commented out uartlite: remove IRQF_SAMPLE_RANDOM which is now a no-op drivers: hv: remove IRQF_SAMPLE_RANDOM which is now a no-op xen-blkfront: remove IRQF_SAMPLE_RANDOM which is now a no-op n2_crypto: remove IRQF_SAMPLE_RANDOM which is now a no-op pda_power: remove IRQF_SAMPLE_RANDOM which is now a no-op i2c-pmcmsp: remove IRQF_SAMPLE_RANDOM which is now a no-op input/serio/hp_sdc.c: remove IRQF_SAMPLE_RANDOM which is now a no-op mfd: remove IRQF_SAMPLE_RANDOM which is now a no-op ...
2012-07-25genirq: Allow irq chips to mark themself oneshot safeThomas Gleixner
Some interrupt chips like MSI are oneshot safe by implementation. For those interrupts we can avoid the mask/unmask sequence for threaded interrupt handlers. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1207132056540.32033@ionos Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Avi Kivity <avi@redhat.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Jan Kiszka <jan.kiszka@web.de>
2012-07-22merge task_work and rcu_head, get rid of separate allocation for keyring caseAl Viro
task_work and rcu_head are identical now; merge them (calling the result struct callback_head, rcu_head #define'd to it), kill separate allocation in security/keys since we can just use cred->rcu now. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-22trimming task_work: kill ->dataAl Viro
get rid of the only user of ->data; this is _not_ the final variant - in the end we'll have task_work and rcu_head identical and just use cred->rcu, at which point the separate allocation will be gone completely. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-19random: remove rand_initialize_irq()Theodore Ts'o
With the new interrupt sampling system, we are no longer using the timer_rand_state structure in the irq descriptor, so we can stop initializing it now. [ Merged in fixes from Sedat to find some last missing references to rand_initialize_irq() ] Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Sedat Dilek <sedat.dilek@gmail.com>
2012-06-04Merge branches 'irq-urgent-for-linus' and 'smp-hotplug-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq and smpboot updates from Thomas Gleixner: "Just cleanup patches with no functional change and a fix for suspend issues." * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq: Introduce irq_do_set_affinity() to reduce duplicated code genirq: Add IRQS_PENDING for nested and simple irq * 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: smpboot, idle: Fix comment mismatch over idle_threads_init() smpboot, idle: Optimize calls to smp_processor_id() in idle_threads_init()
2012-06-01Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull second pile of signal handling patches from Al Viro: "This one is just task_work_add() series + remaining prereqs for it. There probably will be another pull request from that tree this cycle - at least for helpers, to get them out of the way for per-arch fixes remaining in the tree." Fix trivial conflict in kernel/irq/manage.c: the merge of Andrew's pile had brought in commit 97fd75b7b8e0 ("kernel/irq/manage.c: use the pr_foo() infrastructure to prefix printks") which changed one of the pr_err() calls that this merge moves around. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: keys: kill task_struct->replacement_session_keyring keys: kill the dummy key_replace_session_keyring() keys: change keyctl_session_to_parent() to use task_work_add() genirq: reimplement exit_irq_thread() hook via task_work_add() task_work_add: generic process-context callbacks avr32: missed _TIF_NOTIFY_RESUME on one of do_notify_resume callers parisc: need to check NOTIFY_RESUME when exiting from syscall move key_repace_session_keyring() into tracehook_notify_resume() TIF_NOTIFY_RESUME is defined on all targets now
2012-06-01kernel/irq/manage.c: use the pr_foo() infrastructure to prefix printksAndrew Morton
Use the module-wide pr_fmt() mechanism rather than open-coding "genirq: " everywhere. Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-24genirq: Introduce irq_do_set_affinity() to reduce duplicated codeJiang Liu
All invocations of chip->irq_set_affinity() are doing the same return value checks. Let them all use a common function. [ tglx: removed the silly likely while at it ] Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: Keping Chen <chenkeping@huawei.com> Link: http://lkml.kernel.org/r/1333120296-13563-3-git-send-email-jiang.liu@huawei.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-05-24genirq: reimplement exit_irq_thread() hook via task_work_add()Oleg Nesterov
exit_irq_thread() and task->irq_thread are needed to handle the unexpected (and unlikely) exit of irq-thread. We can use task_work instead and make this all private to kernel/irq/manage.c, cleanup plus micro-optimization. 1. rename exit_irq_thread() to irq_thread_dtor(), make it static, and move it up before irq_thread(). 2. change irq_thread() to do task_work_add(irq_thread_dtor) at the start and task_work_cancel() before return. tracehook_notify_resume() can never play with kthreads, only do_exit()->exit_task_work() can call the callback and this is what we want. 3. remove task_struct->irq_thread and the special hook in do_exit(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: David Howells <dhowells@redhat.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Alexander Gordeev <agordeev@redhat.com> Cc: Chris Zankel <chris@zankel.net> Cc: David Smith <dsmith@redhat.com> Cc: "Frank Ch. Eigler" <fche@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-23Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/umlLinus Torvalds
Pull UML updates from Richard Weinberger: "Most changes are bug fixes and cleanups" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: um: missing checks of __put_user()/__get_user() return values um: stub_rt_sigsuspend isn't needed these days anymore um/x86: merge (and trim) 32- and 64-bit variants of ptrace.h irq: Remove irq_chip->release() um: Remove CONFIG_IRQ_RELEASE_METHOD um: Remove usage of irq_chip->release() um: Implement um_free_irq() um: Fix __swp_type() um: Implement a custom pte_same() function um: Add BUG() to do_ops()'s error path um: Remove unused variables um: bury unused _TIF_RESTORE_SIGMASK um: wrong sigmask saved in case of multiple sigframes um: add TIF_NOTIFY_RESUME um: ->restart_block.fn needs to be reset on sigreturn
2012-05-21irq: Remove irq_chip->release()Richard Weinberger
As it's only user (UML) does no longer need it we can get rid of it. Signed-off-by: Richard Weinberger <richard@nod.at> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
2012-04-19genirq: Be more informative on irq type mismatchThomas Gleixner
We require that shared interrupts agree on a few flag settings. Right now we silently return with an error code without giving any hint why we reject it. Make the printout unconditionally and actually useful by printing the flags of the new and the already registered action. Convert all printks to pr_* and use a proper prefix while at it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-04-19genirq: Reject bogus threaded irq requestsThomas Gleixner
Requesting a threaded interrupt without a primary handler and without IRQF_ONESHOT set is dangerous. The core will use the default primary handler for it, which merily wakes the thread. For a level type interrupt this results in an interrupt storm, because the interrupt line is reenabled after the primary handler runs. The device has still the line asserted, which brings us back into the primary handler. While this works for edge type interrupts, we play it safe and reject unconditionally because we can't say for sure which type this interrupt really has. The type flags are unreliable as the underlying chip implementation can override them. And we cannot assume that developers using that interface know what they are doing. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-29genirq: Respect NUMA node affinity in setup_irq_irq affinity()Prarit Bhargava
We respect node affinity of devices already in the irq descriptor allocation, but we ignore it for the initial interrupt affinity setup, so the interrupt might be routed to a different node. Restrict the default affinity mask to the node on which the irq descriptor is allocated. [ tglx: Massaged changelog ] Signed-off-by: Prarit Bhargava <prarit@redhat.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: David Rientjes <rientjes@google.com> Link: http://lkml.kernel.org/r/1332788538-17425-1-git-send-email-prarit@redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-29genirq: Get rid of unneeded force parameter in irq_finalize_oneshot()Alexander Gordeev
The only place irq_finalize_oneshot() is called with force parameter set is the threaded handler error exit path. But IRQTF_RUNTHREAD is dropped at this point and irq_wake_thread() is not going to set it again, since PF_EXITING is set for this thread already. So irq_finalize_oneshot() will drop the threads bit in threads_oneshot anyway and hence the force parameter is superfluous. Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Link: http://lkml.kernel.org/r/20120321162234.GP24806@dhcp-26-207.brq.redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-16genirq: Remove paranoid warnons and bogus fixupsThomas Gleixner
Alexander pointed out that the warnons in the regular exit path are bogus and the thread_mask one actually could be triggered when __setup_irq() hands out that thread_mask again after __free_irq() dropped irq_desc->lock. Thinking more about it, neither IRQTF_RUNTHREAD nor the bit in thread_mask can be set as this is the regular exit path. We come here due to: __free_irq() remove action from desc synchronize_irq() kthread_stop() So synchronize_irq() makes sure that the thread finished running and cleaned up both the thread_active count and thread_mask. After that point nothing can set IRQTF_RUNTHREAD on this action. So the warnons and the cleanups are pointless. Reported-by: Alexander Gordeev <agordeev@redhat.com> Cc: Ido Yariv <ido@wizery.com> Link: http://lkml.kernel.org/r/20120315190755.GA6732@dhcp-26-207.brq.redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-14genirq: Flush the irq thread on synchronizationIdo Yariv
The current implementation does not always flush the threaded handler when disabling the irq. In case the irq handler was called, but the threaded handler hasn't started running yet, the interrupt will be flagged as pending, and the handler will not run. This implementation has some issues: First, if the interrupt is a wake source and flagged as pending, the system will not be able to suspend. Second, when quickly disabling and re-enabling the irq, the threaded handler might continue to run after the irq is re-enabled without the irq handler being called first. This might be an unexpected behavior. In addition, it might be counter-intuitive that the threaded handler will not be called even though the irq handler was called and returned IRQ_WAKE_THREAD. Fix this by always waiting for the threaded handler to complete in synchronize_irq(). [ tglx: Massaged comments, added WARN_ONs and the missing IRQTF_RUNTHREAD check in exit_irq_thread() ] Signed-off-by: Ido Yariv <ido@wizery.com> Link: http://lkml.kernel.org/r/1322843052-7166-1-git-send-email-ido@wizery.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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>
2012-03-09genirq: No need to check IRQTF_DIED before stopping a thread handlerAlexander Gordeev
Since 63706172f332fd3f6e7458ebfb35fa6de9c21dc5 kthread_stop() is not afraid of dead kernel threads. So no need to check if a thread is alive before stopping it. These checks still were racy. Reported-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Link: http://lkml.kernel.org/r/20120309135939.GC2114@dhcp-26-207.brq.redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-09genirq: Get rid of unnecessary irqaction field in task_structAlexander Gordeev
When a new thread handler is created, an irqaction is passed to it as data. Not only that irqaction is stored in task_struct by the handler for later use, but also a structure associated with the kernel thread keeps this value as long as the thread exists. This fix kicks irqaction out off task_struct. Yes, I introduce new bit field. But it allows not only to eliminate the duplicate, but also shortens size of task_struct. Reported-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Link: http://lkml.kernel.org/r/20120309135925.GB2114@dhcp-26-207.brq.redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-09genirq: Fix incorrect check for forced IRQ thread handlerAlexander Gordeev
We do not want a bitwise AND between boolean operands Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Link: http://lkml.kernel.org/r/20120309135912.GA2114@dhcp-26-207.brq.redhat.com Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-07genirq: Clear action->thread_mask if IRQ_ONESHOT is not setThomas Gleixner
Xommit ac5637611(genirq: Unmask oneshot irqs when thread was not woken) fails to unmask when a !IRQ_ONESHOT threaded handler is handled by handle_level_irq. This happens because thread_mask is or'ed unconditionally in irq_wake_thread(), but for !IRQ_ONESHOT interrupts never cleared. So the check for !desc->thread_active fails and keeps the interrupt disabled. Keep the thread_mask zero for !IRQ_ONESHOT interrupts. Document the thread_mask magic while at it. Reported-and-tested-by: Sven Joachim <svenjoac@gmx.de> Reported-and-tested-by: Stefan Lippers-Hollmann <s.l-h@gmx.de> Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
2012-01-08Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (53 commits) Kconfig: acpi: Fix typo in comment. misc latin1 to utf8 conversions devres: Fix a typo in devm_kfree comment btrfs: free-space-cache.c: remove extra semicolon. fat: Spelling s/obsolate/obsolete/g SCSI, pmcraid: Fix spelling error in a pmcraid_err() call tools/power turbostat: update fields in manpage mac80211: drop spelling fix types.h: fix comment spelling for 'architectures' typo fixes: aera -> area, exntension -> extension devices.txt: Fix typo of 'VMware'. sis900: Fix enum typo 'sis900_rx_bufer_status' decompress_bunzip2: remove invalid vi modeline treewide: Fix comment and string typo 'bufer' hyper-v: Update MAINTAINERS treewide: Fix typos in various parts of the kernel, and fix some comments. clockevents: drop unknown Kconfig symbol GENERIC_CLOCKEVENTS_MIGR gpio: Kconfig: drop unknown symbol 'CS5535_GPIO' leds: Kconfig: Fix typo 'D2NET_V2' sound: Kconfig: drop unknown symbol ARCH_CLPS7500 ... Fix up trivial conflicts in arch/powerpc/platforms/40x/Kconfig (some new kconfig additions, close to removed commented-out old ones)
2011-12-02genirq: Fix race condition when stopping the irq threadIdo Yariv
In irq_wait_for_interrupt(), the should_stop member is verified before setting the task's state to TASK_INTERRUPTIBLE and calling schedule(). In case kthread_stop sets should_stop and wakes up the process after should_stop is checked by the irq thread but before the task's state is changed, the irq thread might never exit: kthread_stop irq_wait_for_interrupt ------------ ---------------------- ... ... while (!kthread_should_stop()) { kthread->should_stop = 1; wake_up_process(k); wait_for_completion(&kthread->exited); ... set_current_state(TASK_INTERRUPTIBLE); ... schedule(); } Fix this by checking if the thread should stop after modifying the task's state. [ tglx: Simplified it a bit ] Signed-off-by: Ido Yariv <ido@wizery.com> Link: http://lkml.kernel.org/r/1322740508-22640-1-git-send-email-ido@wizery.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@kernel.org
2011-11-17genirq: Don't allow per cpu interrupts to be suspendedMarc Zyngier
The power management functions related to interrupts do not know (yet) about per-cpu interrupts and end up calling the wrong low-level methods to enable/disable interrupts. This leads to all kind of interesting issues (action taken on one CPU only, updating a refcount which is not used otherwise...). The workaround for the time being is simply to flag these interrupts with IRQF_NO_SUSPEND. At least on ARM, these interrupts are actually dealt with at the architecture level. Reported-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1321446459-31409-1-git-send-email-marc.zyngier@arm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-11-13Merge branch 'master' into for-nextJiri Kosina
Sync with Linus tree to have 157550ff ("mtd: add GPMI-NAND driver in the config and Makefile") as I have patch depending on that one.
2011-10-29irq: Fix comment typo ist->isJavi Merino
Signed-off-by: Javi Merino <javi.merino@arm.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-10-04genirq: Fix fatfinered fixup reallyThomas Gleixner
Putting the argument inside the quote does not really help. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-10-03genirq: percpu: allow interrupt type to be set at enable timeMarc Zyngier
As request_percpu_irq() doesn't allow for a percpu interrupt to have its type configured (it is generally impossible to configure it on all CPUs at once), add a 'type' argument to enable_percpu_irq(). This allows some low-level, board specific init code to be switched to a generic API. [ tglx: Added WARN_ON argument ] Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Abhijeet Dharmapurikar <adharmap@codeaurora.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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>
2011-09-12genirq: Add IRQCHIP_SKIP_SET_WAKE flagSantosh Shilimkar
Some irq chips need the irq_set_wake() functionality, but do not require a irq_set_wake() callback. Instead of forcing an empty callback to be implemented add a flag which notes this fact. Check for the flag in set_irq_wake_real() and return success when set. Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Cc: Thomas Gleixner <tglx@linutronix.de>
2011-08-23Revert "irq: Always set IRQF_ONESHOT if no primary handler is specified"Linus Torvalds
This reverts commit f3637a5f2e2eb391ff5757bc83fb5de8f9726464. It turns out that this breaks several drivers, one example being OMAP boards which use the on-board OMAP UARTs and the omap-serial driver that will not boot to userspace after the commit. Paul Walmsley reports that enabling CONFIG_DEBUG_SHIRQ reveals 'IRQ handler type mismatch' errors: IRQ handler type mismatch for IRQ 74 current handler: serial idle ... and the reason is that setting IRQF_ONESHOT will now result in those interrupt handlers having different IRQF flags, and thus being unsharable. So the commit log in the reverted commit: "Since it is required for those users and there is no difference for others it makes sense to add this flag unconditionally." is simply not true: there may not be any difference from a "actions at irq time", but there is a *big* difference wrt this flag testing irq management (see __setup_irq() in kernel/irq/manage.c). One solution may be to stop verifying IRQF_ONESHOT in __setup_irq(), but right now the safe course of action is to revert the change. Let's revisit this in a later merge window. Reported-by: Paul Walmsley <paul@pwsan.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Requested-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Acked-by: Thomas Gleixner <tglx@linutronix.de> 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>
2011-07-28irq: Always set IRQF_ONESHOT if no primary handler is specifiedSebastian Andrzej Siewior
If no primary handler is specified then a default one is assigned which always returns IRQ_WAKE_THREAD. This handler requires the IRQF_ONESHOT flag on LEVEL / EIO typed irqs because the source of interrupt is not disabled. Since it is required for those users and there is no difference for others it makes sense to add this flag unconditionally. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: http://lkml.kernel.org/r/1310070737-18514-1-git-send-email-bigeasy@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-06-10genirq: Prevent potential NULL dereference in irq_set_irq_wake()Jesper Juhl
In kernel/irq/manage.c::irq_set_irq_wake() we call irq_get_desc_buslock() which may return NULL, but the code dereferences the result unconditionally. irq_set_irq_wake() has lots of callers - I checked a few and I couldn't find anything that guarantees that they won't call it with some input that will cause irq_get_desc_buslock() to return NULL, so I think it's a good thing to test and -EINVAL was the most sane error code in this situation that I could think of. Not all callers test the return value of irq_set_irq_wake(), but those that do take != 0 to mean error as far as I can see, so they should be fine. I guess those that don't test actually should, but that's a different issue. Signed-off-by: Jesper Juhl <jj@chaosbits.net> Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1106092300360.17868@swampdragon.chaosbits.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-06-03irq: Handle spurios irq detection for threaded irqsSebastian Andrzej Siewior
The detection of spurios interrupts is currently limited to first level handler. In force-threaded mode we never notice if the threaded irq does not feel responsible. This patch catches the return value of the threaded handler and forwards it to the spurious detector. If the primary handler returns only IRQ_WAKE_THREAD then the spourious detector ignores it because it gets called again from the threaded handler. [ tglx: Report the erroneous return value early and bail out ] Signed-off-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc> Link: http://lkml.kernel.org/r/1306824972-27067-2-git-send-email-sebastian@breakpoint.cc Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-04-23genirq: Support per-IRQ thread disabling.Paul Mundt
This adds support for disabling threading on a per-IRQ basis via the IRQ status instead of the IRQ flow, which is necessary for interrupts that don't follow the natural IRQ flow channels, such as those that are virtually created. The new APIs added are simply: irq_set_thread() irq_set_nothread() which follow the rest of the IRQ status routines. Chained handlers also have IRQ_NOTHREAD set on them automatically, making the lack of threading explicit rather than implicit. Subsequently, the nothread flag can be viewed through the standard genirq debugging facilities. [ tglx: Fixed cleanup fallout ] Signed-off-by: Paul Mundt <lethal@linux-sh.org> Link: http://lkml.kernel.org/r/%3C20110406210135.GF18426%40linux-sh.org%3E Signed-off-by: Thomas Gleixner <tglx@linutronix.de>