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2026-02-10Merge tag 'irq-msi-2026-02-09' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull MSI updates from Thomas Gleixner: "Updates for the [PCI] MSI subsystem: - Add interrupt redirection infrastructure Some PCI controllers use a single demultiplexing interrupt for the MSI interrupts of subordinate devices. This prevents setting the interrupt affinity of device interrupts, which causes device interrupts to be delivered to a single CPU. That obviously is counterproductive for multi-queue devices and interrupt balancing. To work around this limitation the new infrastructure installs a dummy irq_set_affinity() callback which captures the affinity mask and picks a redirection target CPU out of the mask. When the PCI controller demultiplexes the interrupts it invokes a new handling function in the core, which either runs the interrupt handler in the context of the target CPU or delegates it to irq_work on the target CPU. - Utilize the interrupt redirection mechanism in the PCI DWC host controller driver. This allows affinity control for the subordinate device MSI interrupts instead of being randomly executed on the CPU which runs the demultiplex handler. - Replace the binary 64-bit MSI flag with a DMA mask Some PCI devices have PCI_MSI_FLAGS_64BIT in the MSI capability, but implement less than 64 address bits. This breaks on platforms where such a device is assigned an MSI address higher than what's supported. With the binary 64-bit flag there is no other choice than disabling 64-bit MSI support which leaves the device disfunctional. By using a DMA mask the address limit of a device can be described correctly which provides support for the above scenario. - Make use of the DMA mask based address limit in the hda/intel and radeon drivers to enable them on affected platforms - The usual small cleanups and improvements" * tag 'irq-msi-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: ALSA: hda/intel: Make MSI address limit based on the device DMA limit drm/radeon: Make MSI address limit based on the device DMA limit PCI/MSI: Check the device specific address mask in msi_verify_entries() PCI/MSI: Convert the boolean no_64bit_msi flag to a DMA address mask genirq/redirect: Prevent writing MSI message on affinity change PCI/MSI: Unmap MSI-X region on error genirq: Update effective affinity for redirected interrupts PCI: dwc: Enable MSI affinity support PCI: dwc: Code cleanup genirq: Add interrupt redirection infrastructure genirq/msi: Correct kernel-doc in <linux/msi.h>
2026-02-10Merge tag 'irq-core-2026-02-09' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq core updates from Thomas Gleixner: "Updates for the interrupt core subsystem: - Remove the interrupt timing infrastructure This was added seven years ago to be used for power management purposes, but that integration never happened. - Clean up the remaining setup_percpu_irq() users The memory allocator is available when interrupts can be requested so there is not need for static irq_action. Move the remaining users to request_percpu_irq() and delete the historical cruft. - Warn when interrupt flag inconsistencies are detected in request*_irq(). Inconsistent flags can lead to hard to diagnose malfunction. The fallout of this new warning has been addressed in next and the fixes are coming in via the maintainer trees and the tip irq/cleanup pull requests. - Invoke affinity notifier when CPU hotplug breaks affinity Otherwise the code using the notifier misses the affinity change and operates on stale information. - The usual cleanups and improvements" * tag 'irq-core-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq/proc: Replace snprintf with strscpy in register_handler_proc genirq/cpuhotplug: Notify about affinity changes breaking the affinity mask genirq: Move clear of kstat_irqs to free_desc() genirq: Warn about using IRQF_ONESHOT without a threaded handler irqdomain: Fix up const problem in irq_domain_set_name() genirq: Remove setup_percpu_irq() clocksource/drivers/mips-gic-timer: Move GIC timer to request_percpu_irq() MIPS: Move IP27 timer to request_percpu_irq() MIPS: Move IP30 timer to request_percpu_irq() genirq: Remove __request_percpu_irq() helper genirq: Remove IRQ timing tracking infrastructure
2026-01-13genirq/cpuhotplug: Notify about affinity changes breaking the affinity maskImran Khan
During CPU offlining the interrupts affined to that CPU are moved to other online CPUs, which might break the original affinity mask if the outgoing CPU was the last online CPU in that mask. This change is not propagated to irq_desc::affinity_notify(), which leaves users of the affinity notifier mechanism with stale information. Avoid this by scheduling affinity change notification work for interrupts that were affined to the CPU being offlined, if the new target CPU is not part of the original affinity mask. Since irq_set_affinity_locked() uses the same logic to schedule affinity change notification work, split out this logic into a dedicated function and use that at both places. [ tglx: Removed the EXPORT(), removed the !SMP stub, moved the prototype, added a lockdep assert instead of a comment, fixed up coding style and name space. Polished and clarified the change log ] Signed-off-by: Imran Khan <imran.f.khan@oracle.com> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Link: https://patch.msgid.link/20260113143727.1041265-1-imran.f.khan@oracle.com
2026-01-13genirq: Warn about using IRQF_ONESHOT without a threaded handlerSebastian Andrzej Siewior
IRQF_ONESHOT disables the interrupt source until after the threaded handler completed its work. This is needed to allow the threaded handler to run - otherwise the CPU will get back to the interrupt handler because the interrupt source remains active and the threaded handler will not able to do its work. Specifying IRQF_ONESHOT without a threaded handler does not make sense. It could be a leftover if the handler _was_ threaded and changed back to primary and the flag was not removed. This can be problematic in the `threadirqs' case because the handler is exempt from forced-threading. This in turn can become a problem on a PREEMPT_RT system if the handler attempts to acquire sleeping locks. Warn about missing threaded handlers with the IRQF_ONESHOT flag. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Link: https://patch.msgid.link/20260112134013.eQWyReHR@linutronix.de
2025-12-15genirq: Add interrupt redirection infrastructureRadu Rendec
Add infrastructure to redirect interrupt handler execution to a different CPU when the current CPU is not part of the interrupt's CPU affinity mask. This is primarily aimed at (de)multiplexed interrupts, where the child interrupt handler runs in the context of the parent interrupt handler, and therefore CPU affinity control for the child interrupt is typically not available. With the new infrastructure, the child interrupt is allowed to freely change its affinity setting, independently of the parent. If the interrupt handler happens to be triggered on an "incompatible" CPU (a CPU that's not part of the child interrupt's affinity mask), the handler is redirected and runs in IRQ work context on a "compatible" CPU. No functional change is being made to any existing irqchip driver, and irqchip drivers must be explicitly modified to use the newly added infrastructure to support interrupt redirection. Originally-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Radu Rendec <rrendec@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/linux-pci/878qpg4o4t.ffs@tglx/ Link: https://patch.msgid.link/20251128212055.1409093-2-rrendec@redhat.com
2025-12-15genirq: Remove setup_percpu_irq()Marc Zyngier
setup_percpu_irq() was always a bad kludge, and should have never been there the first place. Now that the last users are gone, remove it for good. Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://patch.msgid.link/20251210082242.360936-7-maz@kernel.org
2025-12-15genirq: Remove __request_percpu_irq() helperMarc Zyngier
With the IRQ timing stuff being gone, there is no need to specify a flag when requesting a percpu interrupt. Not only IRQF_TIMER was the only flag (set of flags actually) allowed, but nobody ever passed it. Get rid of __request_percpu_irq(), which was only getting 0 as flags, and promote request_percpu_irq_affinity() as its replacement. Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jinjie Ruan <ruanjinjie@huawei.com> Link: https://patch.msgid.link/20251210082242.360936-3-maz@kernel.org
2025-12-15genirq: Remove IRQ timing tracking infrastructureMarc Zyngier
The IRQ timing tracking infrastructure was merged in 2019, but was never plumbed in, is not selectable, and is therefore never used. As Daniel agrees that there is little hope for this infrastructure to be completed in the near term, drop it altogether. Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jinjie Ruan <ruanjinjie@huawei.com> Link: https://lore.kernel.org/r/87zf7vex6h.wl-maz@kernel.org Link: https://patch.msgid.link/20251210082242.360936-2-maz@kernel.org
2025-12-13genirq: Don't overwrite interrupt thread flags on setupThomas Gleixner
Chris reported that the recent affinity management changes result in overwriting the already initialized thread flags. Use set_bit() to set the affinity bit instead of assigning the bit value to the flags. Fixes: 801afdfbfcd9 ("genirq: Fix interrupt threads affinity vs. cpuset isolated partitions") Reported-by: Chris Mason <clm@meta.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Frederic Weisbecker <frederic@kernel.org> Link: https://patch.msgid.link/87ecp0e4cf.ffs@tglx Closes: https://lore.kernel.org/all/20251212014848.3509622-1-clm@meta.com
2025-12-10genirq: Allow NULL affinity for setup_percpu_irq()Marc Zyngier
setup_percpu_irq() was forgotten when the percpu_devid infrastructure was updated to deal with CPU affinities. In order to keep ignoring users of this legacy API, provide sensible defaults by setting the affinity to cpu_online_mask if none was provided by the caller. Fixes: bdf4e2ac295fe ("genirq: Allow per-cpu interrupt sharing for non-overlapping affinities") Reported-by: Daniel Thompson <danielt@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://patch.msgid.link/20251205091814.3944205-1-maz@kernel.org Closes: https://lore.kernel.org/r/aTFozefMQRg7lYxh@aspen.lan
2025-12-02Merge tag 'irq-core-2025-11-30' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq core updates from Thomas Gleixner: "Updates for the interrupt core and treewide cleanups: - Rework of the Per Processor Interrupt (PPI) management on ARM[64] PPI support was built under the assumption that the systems are homogenous so that the same CPU local device types are connected to them. That's unfortunately wishful thinking and created horrible workarounds. This rework provides affinity management for PPIs so that they can be individually configured in the firmware tables and mops up the related drivers all over the place. - Prevent CPUSET/isolation changes to arbitrarily affine interrupt threads to random CPUs, which ignores user or driver settings. - Plug a harmless race in the interrupt affinity proc interface, which allows to see a half updated mask - Adjust the priority of secondary interrupt threads on RT, so that the combination of primary and secondary thread emulates the hardware interrupt plus thread scenario. Having them at the same priority can cause starvation issues in some drivers" * tag 'irq-core-2025-11-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits) genirq: Remove cpumask availability check on kthread affinity setting genirq: Fix interrupt threads affinity vs. cpuset isolated partitions genirq: Prevent early spurious wake-ups of interrupt threads genirq: Use raw_spinlock_irq() in irq_set_affinity_notifier() genirq/manage: Reduce priority of forced secondary interrupt handler genirq/proc: Fix race in show_irq_affinity() genirq: Fix percpu_devid irq affinity documentation perf: arm_pmu: Kill last use of per-CPU cpu_armpmu pointer irqdomain: Kill of_node_to_fwnode() helper genirq: Kill irq_{g,s}et_percpu_devid_partition() irqchip: Kill irq-partition-percpu irqchip/apple-aic: Drop support for custom PMU irq partitions irqchip/gic-v3: Drop support for custom PPI partitions coresight: trbe: Request specific affinities for per CPU interrupts perf: arm_spe_pmu: Request specific affinities for per CPU interrupts perf: arm_pmu: Request specific affinities for per CPU NMIs/interrupts genirq: Add request_percpu_irq_affinity() helper genirq: Allow per-cpu interrupt sharing for non-overlapping affinities genirq: Update request_percpu_nmi() to take an affinity genirq: Add affinity to percpu_devid interrupt requests ...
2025-11-22genirq: Remove cpumask availability check on kthread affinity settingFrederic Weisbecker
Failing to allocate the affinity mask of an interrupt descriptor fails the whole descriptor initialization. It is then guaranteed that the cpumask is always available whenever the related interrupt objects are alive, such as the kthread handler. Therefore remove the superfluous check since it is merely a historical leftover. Get rid also of the comments above it that are obsolete and useless. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://patch.msgid.link/20251121143500.42111-4-frederic@kernel.org
2025-11-22genirq: Fix interrupt threads affinity vs. cpuset isolated partitionsFrederic Weisbecker
When a cpuset isolated partition is created / updated or destroyed, the interrupt threads are affined blindly to all the non-isolated CPUs. This happens without taking into account the interrupt threads initial affinity that becomes ignored. For example in a system with 8 CPUs, if an interrupt and its kthread are initially affine to CPU 5, creating an isolated partition with only CPU 2 inside will eventually end up affining the interrupt kthread to all CPUs but CPU 2 (that is CPUs 0,1,3-7), losing the kthread preference for CPU 5. Besides the blind re-affining, this doesn't take care of the actual low level interrupt which isn't migrated. As of today the only way to isolate non managed interrupts, along with their kthreads, is to overwrite their affinity separately, for example through /proc/irq/ To avoid doing that manually, future development should focus on updating the interrupt's affinity whenever cpuset isolated partitions are updated. In the meantime, cpuset shouldn't fiddle with interrupt threads directly. To prevent from that, set the PF_NO_SETAFFINITY flag to them. This is done through kthread_bind_mask() by affining them initially to all possible CPUs as at that point the interrupt is not started up which means the affinity of the hard interrupt is not known. The thread will adjust that once it reaches the handler, which is guaranteed to happen after the initial affinity of the hard interrupt is established. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://patch.msgid.link/20251121143500.42111-3-frederic@kernel.org
2025-11-18genirq: Use raw_spinlock_irq() in irq_set_affinity_notifier()Chengkaitao
Since irq_set_affinity_notifier() may sleep, interrupts are enabled. So raw_spinlock_irqsave() can be replaced with raw_spinlock_irq(). Signed-off-by: Chengkaitao <chengkaitao@kylinos.cn> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://patch.msgid.link/20251118012754.61805-1-pilgrimtao@gmail.com
2025-11-01genirq/manage: Reduce priority of forced secondary interrupt handlerLukas Wunner
Crystal reports that the PCIe Advanced Error Reporting driver gets stuck in an infinite loop on PREEMPT_RT: Both the primary interrupt handler aer_irq() as well as the secondary handler aer_isr() are forced into threads with identical priority. Crystal writes that on the ARM system in question, the primary handler has to clear an error in the Root Error Status register... "before the next error happens, or else the hardware will set the Multiple ERR_COR Received bit. If that bit is set, then aer_isr() can't rely on the Error Source Identification register, so it scans through all devices looking for errors -- and for some reason, on this system, accessing the AER registers (or any Config Space above 0x400, even though there are capabilities located there) generates an Unsupported Request Error (but returns valid data). Since this happens more than once, without aer_irq() preempting, it causes another multi error and we get stuck in a loop." The issue does not show on non-PREEMPT_RT because the primary handler runs in hardirq context and thus can preempt the threaded secondary handler, clear the Root Error Status register and prevent the secondary handler from getting stuck. Emulate the same behavior on PREEMPT_RT by assigning a lower default priority to the secondary handler if the primary handler is forced into a thread. Reported-by: Crystal Wood <crwood@redhat.com> Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Crystal Wood <crwood@redhat.com> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://patch.msgid.link/f6dcdb41be2694886b8dbf4fe7b3ab89e9d5114c.1761569303.git.lukas@wunner.de Closes: https://lore.kernel.org/r/20250902224441.368483-1-crwood@redhat.com/
2025-10-27genirq: Allow per-cpu interrupt sharing for non-overlapping affinitiesMarc Zyngier
Interrupt sharing for percpu-devid interrupts is forbidden, and for good reasons. These are interrupts generated *from* a CPU and handled by itself (timer, for example). Nobody in their right mind would put two devices on the same pin (and if they have, they get to keep the pieces...). But this also prevents more benign cases, where devices are connected to groups of CPUs, and for which the affinities are not overlapping. Effectively, the only thing they share is the interrupt number, and nothing else. Tweak the definition of IRQF_SHARED applied to percpu_devid interrupts to allow this particular use case. This results in extra validation at the point of the interrupt being setup and freed, as well as a tiny bit of extra complexity for interrupts at handling time (to pick the correct irqaction). Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Will Deacon <will@kernel.org> Link: https://patch.msgid.link/20251020122944.3074811-17-maz@kernel.org
2025-10-27genirq: Update request_percpu_nmi() to take an affinityMarc Zyngier
Continue spreading the notion of affinity to the per CPU interrupt request code by updating the call sites that use request_percpu_nmi() (all two of them) to take an affinity pointer. This pointer is firmly NULL for now. Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Will Deacon <will@kernel.org> Link: https://patch.msgid.link/20251020122944.3074811-16-maz@kernel.org
2025-10-27genirq: Add affinity to percpu_devid interrupt requestsMarc Zyngier
Add an affinity field to both the irqaction structure and the interrupt request primitives. Nothing is making use of it yet, and the only value used it NULL, which is used as a shorthand for cpu_possible_mask. This will shortly get used with actual affinities. Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Will Deacon <will@kernel.org> Link: https://patch.msgid.link/20251020122944.3074811-15-maz@kernel.org
2025-10-27genirq: Factor-in percpu irqaction creationMarc Zyngier
Move the code creating a per-cpu irqaction into its own helper, so that future changes to this code can be kept localised. At the same time, fix the documentation which appears to say the wrong thing when it comes to interrupts being automatically enabled (percpu_devid interrupts never are). Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Will Deacon <will@kernel.org> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Link: https://patch.msgid.link/20251020122944.3074811-14-maz@kernel.org
2025-10-24genirq/manage: Add buslock back in to enable_irq()Charles Keepax
The locking was changed from a buslock to a plain lock, but the patch description states there was no functional change. Assuming this was accidental so reverting to using the buslock. Fixes: bddd10c55407 ("genirq/manage: Rework enable_irq()") Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://patch.msgid.link/20251023154901.1333755-4-ckeepax@opensource.cirrus.com
2025-10-24genirq/manage: Add buslock back in to __disable_irq_nosync()Charles Keepax
The locking was changed from a buslock to a plain lock, but the patch description states there was no functional change. Assuming this was accidental so reverting to using the buslock. Fixes: 1b7444446724 ("genirq/manage: Rework __disable_irq_nosync()") Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://patch.msgid.link/20251023154901.1333755-3-ckeepax@opensource.cirrus.com
2025-05-14genirq/manage: Use the correct lock guard in irq_set_irq_wake()Jon Hunter
Commit 8589e325ba4f ("genirq/manage: Rework irq_set_irq_wake()") updated the irq_set_irq_wake() to use the new guards for locking the interrupt descriptor. However, in doing so it inadvertently changed irq_set_irq_wake() such that the 'chip_bus_lock' is no longer acquired. This has caused system suspend tests to fail on some Tegra platforms. Fix this by correcting the guard used in irq_set_irq_wake() to ensure the 'chip_bus_lock' is held. Fixes: 8589e325ba4f ("genirq/manage: Rework irq_set_irq_wake()") Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250514095041.1109783-1-jonathanh@nvidia.com
2025-05-07genirq: Use scoped_guard() to shut clang upThomas Gleixner
This code pattern trips clang up: if (fail) goto undo; guard(lock)(lock); do_stuff(); return 0; undo: ... as it somehow extends the scope of the guard beyond the return statement. Replace it with a scoped guard to help it to get its act together. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Closes: https://lore.kernel.org/oe-kbuild-all/202505071809.ajpPxfoZ-lkp@intel.com/
2025-05-07genirq: Remove unused remove_percpu_irq()Dr. David Alan Gilbert
remove_percpu_irq() has been unused since it was added in 2011 by commit 31d9d9b6d830 ("genirq: Add support for per-cpu dev_id interrupts") Remove it. Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250420164656.112641-1-linux@treblig.org
2025-05-07genirq/manage: Rework irq_set_irqchip_state()Thomas Gleixner
Use the new guards to get and lock the interrupt descriptor and tidy up the code. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/20250429065422.670808288@linutronix.de
2025-05-07genirq/manage: Rework irq_get_irqchip_state()Thomas Gleixner
Use the new guards to get and lock the interrupt descriptor and tidy up the code. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/20250429065422.612184618@linutronix.de
2025-05-07genirq/manage: Rework teardown_percpu_nmi()Thomas Gleixner
Use the new guards to get and lock the interrupt descriptor and tidy up the code. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/20250429065422.552884529@linutronix.de
2025-05-07genirq/manage: Rework prepare_percpu_nmi()Thomas Gleixner
Use the new guards to get and lock the interrupt descriptor and tidy up the code. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/20250429065422.494561120@linutronix.de
2025-05-07genirq/manage: Rework disable_percpu_irq()Thomas Gleixner
Use the new guards to get and lock the interrupt descriptor and tidy up the code. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/20250429065422.435932527@linutronix.de
2025-05-07genirq/manage: Rework irq_percpu_is_enabled()Thomas Gleixner
Use the new guards to get and lock the interrupt descriptor and tidy up the code. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/20250429065422.376836282@linutronix.de
2025-05-07genirq/manage: Rework enable_percpu_irq()Thomas Gleixner
Use the new guards to get and lock the interrupt descriptor and tidy up the code. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/20250429065422.315844964@linutronix.de
2025-05-07genirq/manage: Rework irq_set_parent()Thomas Gleixner
Use the new guards to get and lock the interrupt descriptor and tidy up the code. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/20250429065422.258216558@linutronix.de
2025-05-07genirq/manage: Rework can_request_irq()Thomas Gleixner
Use the new guards to get and lock the interrupt descriptor and tidy up the code. Make the return value boolean to reflect it's meaning. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/20250429065422.187250840@linutronix.de
2025-05-07genirq/manage: Rework irq_set_irq_wake()Thomas Gleixner
Use the new guards to get and lock the interrupt descriptor and tidy up the code. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/87ldrhq0hc.ffs@tglx
2025-05-07genirq/manage: Rework enable_irq()Thomas Gleixner
Use the new guards to get and lock the interrupt descriptor and tidy up the code. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/20250429065422.071157729@linutronix.de
2025-05-07genirq/manage: Rework __disable_irq_nosync()Thomas Gleixner
Use the new guards to get and lock the interrupt descriptor and tidy up the code. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/20250429065422.013088277@linutronix.de
2025-05-07genirq/manage: Rework irq_set_vcpu_affinity()Thomas Gleixner
Use the new guards to get and lock the interrupt descriptor and tidy up the code. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/87ikmlq0fk.ffs@tglx
2025-05-07genirq/manage: Rework __irq_apply_affinity_hint()Thomas Gleixner
Use the new guards to get and lock the interrupt descriptor and tidy up the code. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/20250429065421.897188799@linutronix.de
2025-05-07genirq/manage: Rework irq_update_affinity_desc()Thomas Gleixner
Use the new guards to get and lock the interrupt descriptor and tidy up the code. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/20250429065421.830357569@linutronix.de
2025-05-07genirq/manage: Convert to lock guardsThomas Gleixner
Convert lock/unlock pairs to guards. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/20250429065421.771476066@linutronix.de
2025-05-07genirq/manage: Cleanup kernel doc commentsThomas Gleixner
Get rid of the extra tab to make it consistent. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/20250429065421.710273122@linutronix.de
2025-03-10genirq: Make a few functions staticThomas Gleixner
None of these functions are used outside of their source files. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/878qpe2gnx.ffs@tglx
2024-12-03genirq: Reuse irq_thread_fn() for forced thread caseAndy Shevchenko
rq_forced_thread_fn() uses the same action callback as the non-forced variant but with different locking decorations. Reuse irq_thread_fn() here to make that clear. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20241119104339.2112455-3-andriy.shevchenko@linux.intel.com
2024-12-03genirq: Move irq_thread_fn() further up in the codeAndy Shevchenko
In a preparation to reuse irq_thread_fn() move it further up in the code. No functional change intended. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20241119104339.2112455-2-andriy.shevchenko@linux.intel.com
2024-08-27genirq: Get rid of global lock in irq_do_set_affinity()Marc Zyngier
Kunkun Jiang reports that for a workload involving the simultaneous startup of a large number of VMs (for a total of about 200 vcpus), a lot of CPU time gets spent on spinning on the tmp_mask_lock that exists as a static raw spinlock in irq_do_set_affinity(). This lock protects a global cpumask (tmp_mask) that is used as a temporary variable to compute the resulting affinity. While this is triggered by KVM issuing a irq_set_affinity() call each time a vcpu is about to execute, it is obvious that having a single global resource is not very scalable. Since a cpumask can be a fairly large structure on systems with a high core count, a stack allocation is not really appropriate. Instead, turn the global cpumask into a per-CPU variable, removing the need for locking altogether as the code is executed with preemption and interrupts disabled. [ tglx: Moved the per CPU variable declaration outside of the function ] Reported-by: Kunkun Jiang <jiangkunkun@huawei.com> Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Kunkun Jiang <jiangkunkun@huawei.com> Link: https://lore.kernel.org/all/20240826080618.3886694-1-maz@kernel.org Link: https://lore.kernel.org/all/a7fc58e4-64c2-77fc-c1dc-f5eb78dbbb01@huawei.com
2024-07-09task_work: s/task_work_cancel()/task_work_cancel_func()/Frederic Weisbecker
A proper task_work_cancel() API that actually cancels a callback and not *any* callback pointing to a given function is going to be needed for perf events event freeing. Do the appropriate rename to prepare for that. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240621091601.18227-2-frederic@kernel.org
2024-05-14Merge tag 'irq-core-2024-05-12' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull interrupt subsystem updates from Thomas Gleixner: "Core code: - Interrupt storm detection for the lockup watchdog: Lockups which are caused by interrupt storms are not easy to debug because there is no information about the events which make the lockup detector trigger. To make this more user friendly, provide an extenstion to interrupt statistics which allows to take snapshots and an interface to retrieve the delta to the snapshot. Use this new mechanism in the watchdog code to do a two stage lockup analysis by taking the snapshot and printing the deltas for the topmost active interrupts on the second trigger. Note: This contains both the interrupt and the watchdog changes as the latter depend on the former obviously. - Avoid summation loops in the /proc/interrupts output and use the global counter when possible - Skip suspended interrupts on CPU hotplug operations to ensure that they are not delivered before the system resumes the device drivers when coming out of suspend. - On CPU hot-unplug interrupts which are affine to the outgoing CPU are migrated to a different CPU in the affinity mask. This can fail when the CPUs have no vectors left. Instead of giving up try to migrate it to any online CPU and thereby breaking the affinity setting in order to prevent a stale device interrupt which targets an offline CPU - The usual small cleanups Driver code: - Support for the RISCV AIA MSI controller - Make the interrupt allocation for the Loongson PCH controller more flexible to prevent vector exhaustion - The usual set of cleanups and fixes all over the place" * tag 'irq-core-2024-05-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits) irqchip/gic-v3-its: Remove BUG_ON in its_vpe_irq_domain_alloc cpuidle: Avoid explicit cpumask allocation on stack irqchip/sifive-plic: Avoid explicit cpumask allocation on stack irqchip/riscv-aplic-direct: Avoid explicit cpumask allocation on stack irqchip/loongson-eiointc: Avoid explicit cpumask allocation on stack irqchip/gic-v3-its: Avoid explicit cpumask allocation on stack irqchip/irq-bcm6345-l1: Avoid explicit cpumask allocation on stack cpumask: Introduce cpumask_first_and_and() irqchip/irq-brcmstb-l2: Avoid saving mask on shutdown genirq: Reuse irq_is_nmi() genirq/cpuhotplug: Retry with cpu_online_mask when migration fails genirq/cpuhotplug: Skip suspended interrupts when restoring affinity arm64: dts: st: Add interrupt parent to pinctrl on stm32mp251 arm64: dts: st: Add exti1 and exti2 nodes on stm32mp251 ARM: dts: stm32: List exti parent interrupts on stm32mp131 ARM: dts: stm32: List exti parent interrupts on stm32mp151 arm64: Kconfig.platforms: Enable STM32_EXTI for ARCH_STM32 irqchip/stm32-exti: Mark events reserved with RIF configuration check irqchip/stm32-exti: Skip secure events irqchip/stm32-exti: Convert driver to standard PM ...
2024-04-24genirq: Reuse irq_is_nmi()Jinjie Ruan
Move irq_is_nmi() to the internal header file and reuse it all over the place. Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20240423024037.3331215-1-ruanjinjie@huawei.com
2024-04-24genirq/cpuhotplug: Skip suspended interrupts when restoring affinityDavid Stevens
irq_restore_affinity_of_irq() restarts managed interrupts unconditionally when the first CPU in the affinity mask comes online. That's correct during normal hotplug operations, but not when resuming from S3 because the drivers are not resumed yet and interrupt delivery is not expected by them. Skip the startup of suspended interrupts and let resume_device_irqs() deal with restoring them. This ensures that irqs are not delivered to drivers during the noirq phase of resuming from S3, after non-boot CPUs are brought back online. Signed-off-by: David Stevens <stevensd@chromium.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20240424090341.72236-1-stevensd@chromium.org
2024-03-25genirq: Introduce IRQF_COND_ONESHOT and use it in pinctrl-amdRafael J. Wysocki
There is a problem when a driver requests a shared interrupt line to run a threaded handler on it without IRQF_ONESHOT set if that flag has been set already for the IRQ in question by somebody else. Namely, the request fails which usually leads to a probe failure even though the driver might have worked just fine with IRQF_ONESHOT, but it does not want to use it by default. Currently, the only way to handle this is to try to request the IRQ without IRQF_ONESHOT, but with IRQF_PROBE_SHARED set and if this fails, try again with IRQF_ONESHOT set. However, this is a bit cumbersome and not very clean. When commit 7a36b901a6eb ("ACPI: OSL: Use a threaded interrupt handler for SCI") switched the ACPI subsystem over to using a threaded interrupt handler for the SCI, it had to use IRQF_ONESHOT for it because that's required due to the way the SCI handler works (it needs to walk all of the enabled GPEs before the interrupt line can be unmasked). The SCI interrupt line is not shared with other users very often due to the SCI handling overhead, but on sone systems it is shared and when the other user of it attempts to install a threaded handler, a flags mismatch related to IRQF_ONESHOT may occur. As it turned out, that happened to the pinctrl-amd driver and so commit 4451e8e8415e ("pinctrl: amd: Add IRQF_ONESHOT to the interrupt request") attempted to address the issue by adding IRQF_ONESHOT to the interrupt flags in that driver, but this is now causing an IRQF_ONESHOT-related mismatch to occur on another system which cannot boot as a result of it. Clearly, pinctrl-amd can work with IRQF_ONESHOT if need be, but it should not set that flag by default, so it needs a way to indicate that to the interrupt subsystem. To that end, introdcuce a new interrupt flag, IRQF_COND_ONESHOT, which will only have effect when the IRQ line is shared and IRQF_ONESHOT has been set for it already, in which case it will be promoted to the latter. This is sufficient for drivers sharing the interrupt line with the SCI as it is requested by the ACPI subsystem before any drivers are probed, so they will always see IRQF_ONESHOT set for the interrupt in question. Fixes: 4451e8e8415e ("pinctrl: amd: Add IRQF_ONESHOT to the interrupt request") Reported-by: Francisco Ayala Le Brun <francisco@videowindow.eu> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Cc: 6.8+ <stable@vger.kernel.org> # 6.8+ Closes: https://lore.kernel.org/lkml/CAN-StX1HqWqi+YW=t+V52-38Mfp5fAz7YHx4aH-CQjgyNiKx3g@mail.gmail.com/ Link: https://lore.kernel.org/r/12417336.O9o76ZdvQC@kreacher