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2019-02-18genirq/affinity: Store interrupt sets size in struct irq_affinityMing Lei
The interrupt affinity spreading mechanism supports to spread out affinities for one or more interrupt sets. A interrupt set contains one or more interrupts. Each set is mapped to a specific functionality of a device, e.g. general I/O queues and read I/O queus of multiqueue block devices. The number of interrupts per set is defined by the driver. It depends on the total number of available interrupts for the device, which is determined by the PCI capabilites and the availability of underlying CPU resources, and the number of queues which the device provides and the driver wants to instantiate. The driver passes initial configuration for the interrupt allocation via a pointer to struct irq_affinity. Right now the allocation mechanism is complex as it requires to have a loop in the driver to determine the maximum number of interrupts which are provided by the PCI capabilities and the underlying CPU resources. This loop would have to be replicated in every driver which wants to utilize this mechanism. That's unwanted code duplication and error prone. In order to move this into generic facilities it is required to have a mechanism, which allows the recalculation of the interrupt sets and their size, in the core code. As the core code does not have any knowledge about the underlying device, a driver specific callback will be added to struct affinity_desc, which will be invoked by the core code. The callback will get the number of available interupts as an argument, so the driver can calculate the corresponding number and size of interrupt sets. To support this, two modifications for the handling of struct irq_affinity are required: 1) The (optional) interrupt sets size information is contained in a separate array of integers and struct irq_affinity contains a pointer to it. This is cumbersome and as the maximum number of interrupt sets is small, there is no reason to have separate storage. Moving the size array into struct affinity_desc avoids indirections and makes the code simpler. 2) At the moment the struct irq_affinity pointer which is handed in from the driver and passed through to several core functions is marked 'const'. With the upcoming callback to recalculate the number and size of interrupt sets, it's necessary to remove the 'const' qualifier. Otherwise the callback would not be able to update the data. Implement #1 and store the interrupt sets size in 'struct irq_affinity'. No functional change. [ tglx: Fixed the memcpy() size so it won't copy beyond the size of the source. Fixed the kernel doc comments for struct irq_affinity and de-'This patch'-ed the changelog ] Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Bjorn Helgaas <helgaas@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: linux-block@vger.kernel.org Cc: Sagi Grimberg <sagi@grimberg.me> Cc: linux-nvme@lists.infradead.org Cc: linux-pci@vger.kernel.org Cc: Keith Busch <keith.busch@intel.com> Cc: Sumit Saxena <sumit.saxena@broadcom.com> Cc: Kashyap Desai <kashyap.desai@broadcom.com> Cc: Shivasharan Srikanteshwara <shivasharan.srikanteshwara@broadcom.com> Link: https://lkml.kernel.org/r/20190216172228.423723127@linutronix.de
2019-02-18genirq/affinity: Code consolidationThomas Gleixner
All information and calculations in the interrupt affinity spreading code is strictly unsigned int. Though the code uses int all over the place. Convert it over to unsigned int. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Bjorn Helgaas <helgaas@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: linux-block@vger.kernel.org Cc: Sagi Grimberg <sagi@grimberg.me> Cc: linux-nvme@lists.infradead.org Cc: linux-pci@vger.kernel.org Cc: Keith Busch <keith.busch@intel.com> Cc: Sumit Saxena <sumit.saxena@broadcom.com> Cc: Kashyap Desai <kashyap.desai@broadcom.com> Cc: Shivasharan Srikanteshwara <shivasharan.srikanteshwara@broadcom.com> Link: https://lkml.kernel.org/r/20190216172228.336424556@linutronix.de
2019-02-17Merge tag 'gpio-v5.1-updates-for-linus' of ↵Linus Walleij
git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux into devel gpio updates for v5.1 - support for a new variant of pca953x - documentation fix from Wolfram - some tegra186 name changes - two minor fixes for madera and altera-a10sr
2019-02-14Merge branch 'linus' into irq/coreThomas Gleixner
Pick up upstream changes to avoid conflicts for pending patches.
2019-02-14genirq: Fix wrong name in request_percpu_nmi() descriptionJulien Thierry
ready_percpu_nmi() was the previous name of prepare_percpu_nmi(). Update request_percpu_nmi() comment with the correct function name. Signed-off-by: Julien Thierry <julien.thierry@arm.com> Reported-by: Li Wei <liwei391@huawei.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-02-13genirq: introduce irq_chip_mask_ack_parent()Linus Walleij
The hierarchical irqchip never before ran into a situation where the parent is not "simple", i.e. does not implement .irq_ack() and .irq_mask() like most, but the qcom-pm8xxx.c happens to implement only .irq_mask_ack(). Since we want to make ssbi-gpio a hierarchical child of this irqchip, it must *also* only implement .irq_mask_ack() and call down to the parent, and for this we of course need irq_chip_mask_ack_parent(). Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Brian Masney <masneyb@onstation.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-02-13genirq: introduce irq_domain_translate_twocellBrian Masney
Add a new function irq_domain_translate_twocell() that is to be used as the translate function in struct irq_domain_ops for the v2 IRQ API. This patch also changes irq_domain_xlate_twocell() from the v1 IRQ API to call irq_domain_translate_twocell() in the v2 IRQ API. This required changes to of_phandle_args_to_fwspec()'s arguments so that it can be called from multiple places. Cc: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Brian Masney <masneyb@onstation.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-02-10genirq: Avoid summation loops for /proc/statThomas Gleixner
Waiman reported that on large systems with a large amount of interrupts the readout of /proc/stat takes a long time to sum up the interrupt statistics. In principle this is not a problem. but for unknown reasons some enterprise quality software reads /proc/stat with a high frequency. The reason for this is that interrupt statistics are accounted per cpu. So the /proc/stat logic has to sum up the interrupt stats for each interrupt. This can be largely avoided for interrupts which are not marked as 'PER_CPU' interrupts by simply adding a per interrupt summation counter which is incremented along with the per interrupt per cpu counter. The PER_CPU interrupts need to avoid that and use only per cpu accounting because they share the interrupt number and the interrupt descriptor and concurrent updates would conflict or require unwanted synchronization. Reported-by: Waiman Long <longman@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Waiman Long <longman@redhat.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Davidlohr Bueso <dbueso@suse.de> Cc: Matthew Wilcox <willy@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Kees Cook <keescook@chromium.org> Cc: linux-fsdevel@vger.kernel.org Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Daniel Colascione <dancol@google.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Randy Dunlap <rdunlap@infradead.org> Link: https://lkml.kernel.org/r/20190208135020.925487496@linutronix.de 8<------------- v2: Undo the unintentional layout change of struct irq_desc. include/linux/irqdesc.h | 1 + kernel/irq/chip.c | 12 ++++++++++-- kernel/irq/internals.h | 8 +++++++- kernel/irq/irqdesc.c | 7 ++++++- 4 files changed, 24 insertions(+), 4 deletions(-)
2019-02-10genirq/affinity: Move allocation of 'node_to_cpumask' to ↵Ming Lei
irq_build_affinity_masks() 'node_to_cpumask' is just one temparay variable for irq_build_affinity_masks(), so move it into irq_build_affinity_masks(). No functioanl change. Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: linux-block@vger.kernel.org Cc: Sagi Grimberg <sagi@grimberg.me> Cc: linux-nvme@lists.infradead.org Cc: linux-pci@vger.kernel.org Link: https://lkml.kernel.org/r/20190125095347.17950-2-ming.lei@redhat.com
2019-02-05irqdesc: Add domain handler for NMIsJulien Thierry
NMI handling code should be executed between calls to nmi_enter and nmi_exit. Add a separate domain handler to properly setup NMI context when handling an interrupt requested as NMI. Signed-off-by: Julien Thierry <julien.thierry@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-02-05genirq: Provide NMI handlersJulien Thierry
Provide flow handlers that are NMI safe for interrupts and percpu_devid interrupts. Signed-off-by: Julien Thierry <julien.thierry@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-02-05genirq: Provide NMI management for percpu_devid interruptsJulien Thierry
Add support for percpu_devid interrupts treated as NMIs. Percpu_devid NMIs need to be setup/torn down on each CPU they target. The same restrictions as for global NMIs still apply for percpu_devid NMIs. Signed-off-by: Julien Thierry <julien.thierry@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-02-05genirq: Provide basic NMI management for interrupt linesJulien Thierry
Add functionality to allocate interrupt lines that will deliver IRQs as Non-Maskable Interrupts. These allocations are only successful if the irqchip provides the necessary support and allows NMI delivery for the interrupt line. Interrupt lines allocated for NMI delivery must be enabled/disabled through enable_nmi/disable_nmi_nosync to keep their state consistent. To treat a PERCPU IRQ as NMI, the interrupt must not be shared nor threaded, the irqchip directly managing the IRQ must be the root irqchip and the irqchip cannot be behind a slow bus. Signed-off-by: Julien Thierry <julien.thierry@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-02-04genirq: export irq_chip_set_wake_parent symbolBrian Masney
Export the irq_chip_set_wake_parent symbol so that drivers with hierarchical IRQ chips can be built as a module. Signed-off-by: Brian Masney <masneyb@onstation.org> Reported-by: Mark Brown <broonie@kernel.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-01-29genirq/debugfs: No need to check return value of debugfs_create functionsGreg Kroah-Hartman
When calling debugfs functions, there is no need to ever check the return value. The function can work or not, but the code logic should never do something different based on this. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Marc Zyngier <marc.zyngier@arm.com> Link: https://lkml.kernel.org/r/20190122152151.16139-50-gregkh@linuxfoundation.org
2019-01-18genirq/irqdesc: Fix double increment in alloc_descs()Huacai Chen
The recent rework of alloc_descs() introduced a double increment of the loop counter. As a consequence only every second affinity mask is validated. Remove it. [ tglx: Massaged changelog ] Fixes: c410abbbacb9 ("genirq/affinity: Add is_managed to struct irq_affinity_desc") Signed-off-by: Huacai Chen <chenhc@lemote.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Fuxin Zhang <zhangfx@lemote.com> Cc: Zhangjin Wu <wuzhangjin@gmail.com> Cc: Huacai Chen <chenhuacai@gmail.com> Cc: Dou Liyang <douliyangs@gmail.com> Link: https://lkml.kernel.org/r/1547694009-16261-1-git-send-email-chenhc@lemote.com
2019-01-15genirq: Make sure the initial affinity is not emptySrinivas Ramana
If all CPUs in the irq_default_affinity mask are offline when an interrupt is initialized then irq_setup_affinity() can set an empty affinity mask for a newly allocated interrupt. Fix this by falling back to cpu_online_mask in case the resulting affinity mask is zero. Signed-off-by: Srinivas Ramana <sramana@codeaurora.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arm-msm@vger.kernel.org Link: https://lkml.kernel.org/r/1545312957-8504-1-git-send-email-sramana@codeaurora.org
2019-01-15genirq: Correctly annotate implicit fall throughMathieu Malaterre
There is a plan to build the kernel with -Wimplicit-fallthrough. The fallthrough in __handle_irq_event_percpu() has a fallthrough annotation which is followed by an additional comment and is not recognized by GCC. Separate the 'fall through' and the rest of the comment with a dash so the regular expression used by GCC matches. Signed-off-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190114203633.18557-1-malat@debian.org
2019-01-15genirq: Annotate implicit fall throughMathieu Malaterre
There is a plan to build the kernel with -Wimplicit-fallthrough. The fallthrough in __irq_set_trigger() lacks an annotation. Add it. Signed-off-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190114203154.17125-1-malat@debian.org
2018-12-19genirq/affinity: Add is_managed to struct irq_affinity_descDou Liyang
Devices which use managed interrupts usually have two classes of interrupts: - Interrupts for multiple device queues - Interrupts for general device management Currently both classes are treated the same way, i.e. as managed interrupts. The general interrupts get the default affinity mask assigned while the device queue interrupts are spread out over the possible CPUs. Treating the general interrupts as managed is both a limitation and under certain circumstances a bug. Assume the following situation: default_irq_affinity = 4..7 So if CPUs 4-7 are offlined, then the core code will shut down the device management interrupts because the last CPU in their affinity mask went offline. It's also a limitation because it's desired to allow manual placement of the general device interrupts for various reasons. If they are marked managed then the interrupt affinity setting from both user and kernel space is disabled. That limitation was reported by Kashyap and Sumit. Expand struct irq_affinity_desc with a new bit 'is_managed' which is set for truly managed interrupts (queue interrupts) and cleared for the general device interrupts. [ tglx: Simplify code and massage changelog ] Reported-by: Kashyap Desai <kashyap.desai@broadcom.com> Reported-by: Sumit Saxena <sumit.saxena@broadcom.com> Signed-off-by: Dou Liyang <douliyangs@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-pci@vger.kernel.org Cc: shivasharan.srikanteshwara@broadcom.com Cc: ming.lei@redhat.com Cc: hch@lst.de Cc: bhelgaas@google.com Cc: douliyang1@huawei.com Link: https://lkml.kernel.org/r/20181204155122.6327-3-douliyangs@gmail.com
2018-12-19genirq/core: Introduce struct irq_affinity_descDou Liyang
The interrupt affinity management uses straight cpumask pointers to convey the automatically assigned affinity masks for managed interrupts. The core interrupt descriptor allocation also decides based on the pointer being non NULL whether an interrupt is managed or not. Devices which use managed interrupts usually have two classes of interrupts: - Interrupts for multiple device queues - Interrupts for general device management Currently both classes are treated the same way, i.e. as managed interrupts. The general interrupts get the default affinity mask assigned while the device queue interrupts are spread out over the possible CPUs. Treating the general interrupts as managed is both a limitation and under certain circumstances a bug. Assume the following situation: default_irq_affinity = 4..7 So if CPUs 4-7 are offlined, then the core code will shut down the device management interrupts because the last CPU in their affinity mask went offline. It's also a limitation because it's desired to allow manual placement of the general device interrupts for various reasons. If they are marked managed then the interrupt affinity setting from both user and kernel space is disabled. To remedy that situation it's required to convey more information than the cpumasks through various interfaces related to interrupt descriptor allocation. Instead of adding yet another argument, create a new data structure 'irq_affinity_desc' which for now just contains the cpumask. This struct can be expanded to convey auxilliary information in the next step. No functional change, just preparatory work. [ tglx: Simplified logic and clarified changelog ] Suggested-by: Thomas Gleixner <tglx@linutronix.de> Suggested-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Dou Liyang <douliyangs@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-pci@vger.kernel.org Cc: kashyap.desai@broadcom.com Cc: shivasharan.srikanteshwara@broadcom.com Cc: sumit.saxena@broadcom.com Cc: ming.lei@redhat.com Cc: hch@lst.de Cc: douliyang1@huawei.com Link: https://lkml.kernel.org/r/20181204155122.6327-2-douliyangs@gmail.com
2018-12-19genirq/affinity: Remove excess indentationThomas Gleixner
Plus other coding style issues which stood out while staring at that code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2018-12-18Merge tag 'irqchip-4.21' of ↵Thomas Gleixner
git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core Pull irqchip updates from Marc Zyngier: - A bunch of new irqchip drivers (RDA8810PL, Madera, imx-irqsteer) - Updates for new (and old) platforms (i.MX8MQ, F1C100s) - A number of SPDX cleanups - A workaround for a very broken GICv3 implementation - A platform-msi fix - Various cleanups
2018-12-18genirq: Fix various typos in commentsIngo Molnar
Go over the IRQ subsystem source code (including irqchip drivers) and fix common typos in comments. No change in functionality intended. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jason Cooper <jason@lakedaemon.net> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: linux-kernel@vger.kernel.org
2018-12-13irq/irq_sim: Store multiple interrupt offsets in a bitmapBartosz Golaszewski
Two threads can try to fire the irq_sim with different offsets and will end up fighting for the irq_work asignment. Thomas Gleixner suggested a solution based on a bitfield where we set a bit for every offset associated with an interrupt that should be fired and then iterate over all set bits in the interrupt handler. This is a slightly modified solution using a bitmap so that we don't impose a limit on the number of interrupts one can allocate with irq_sim. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-11-06genirq/matrix: Improve target CPU selection for managed interrupts.Long Li
On large systems with multiple devices of the same class (e.g. NVMe disks, using managed interrupts), the kernel can affinitize these interrupts to a small subset of CPUs instead of spreading them out evenly. irq_matrix_alloc_managed() tries to select the CPU in the supplied cpumask of possible target CPUs which has the lowest number of interrupt vectors allocated. This is done by searching the CPU with the highest number of available vectors. While this is correct for non-managed CPUs it can select the wrong CPU for managed interrupts. Under certain constellations this results in affinitizing the managed interrupts of several devices to a single CPU in a set. The book keeping of available vectors works the following way: 1) Non-managed interrupts: available is decremented when the interrupt is actually requested by the device driver and a vector is assigned. It's incremented when the interrupt and the vector are freed. 2) Managed interrupts: Managed interrupts guarantee vector reservation when the MSI/MSI-X functionality of a device is enabled, which is achieved by reserving vectors in the bitmaps of the possible target CPUs. This reservation decrements the available count on each possible target CPU. When the interrupt is requested by the device driver then a vector is allocated from the reserved region. The operation is reversed when the interrupt is freed by the device driver. Neither of these operations affect the available count. The reservation persist up to the point where the MSI/MSI-X functionality is disabled and only this operation increments the available count again. For non-managed interrupts the available count is the correct selection criterion because the guaranteed reservations need to be taken into account. Using the allocated counter could lead to a failing allocation in the following situation (total vector space of 10 assumed): CPU0 CPU1 available: 2 0 allocated: 5 3 <--- CPU1 is selected, but available space = 0 managed reserved: 3 7 while available yields the correct result. For managed interrupts the available count is not the appropriate selection criterion because as explained above the available count is not affected by the actual vector allocation. The following example illustrates that. Total vector space of 10 assumed. The starting point is: CPU0 CPU1 available: 5 4 allocated: 2 3 managed reserved: 3 3 Allocating vectors for three non-managed interrupts will result in affinitizing the first two to CPU0 and the third one to CPU1 because the available count is adjusted with each allocation: CPU0 CPU1 available: 5 4 <- Select CPU0 for 1st allocation --> allocated: 3 3 available: 4 4 <- Select CPU0 for 2nd allocation --> allocated: 4 3 available: 3 4 <- Select CPU1 for 3rd allocation --> allocated: 4 4 But the allocation of three managed interrupts starting from the same point will affinitize all of them to CPU0 because the available count is not affected by the allocation (see above). So the end result is: CPU0 CPU1 available: 5 4 allocated: 5 3 Introduce a "managed_allocated" field in struct cpumap to track the vector allocation for managed interrupts separately. Use this information to select the target CPU when a vector is allocated for a managed interrupt, which results in more evenly distributed vector assignments. The above example results in the following allocations: CPU0 CPU1 managed_allocated: 0 0 <- Select CPU0 for 1st allocation --> allocated: 3 3 managed_allocated: 1 0 <- Select CPU1 for 2nd allocation --> allocated: 3 4 managed_allocated: 1 1 <- Select CPU0 for 3rd allocation --> allocated: 4 4 The allocation of non-managed interrupts is not affected by this change and is still evaluating the available count. The overall distribution of interrupt vectors for both types of interrupts might still not be perfectly even depending on the number of non-managed and managed interrupts in a system, but due to the reservation guarantee for managed interrupts this cannot be avoided. Expose the new field in debugfs as well. [ tglx: Clarified the background of the problem in the changelog and described it independent of NVME ] Signed-off-by: Long Li <longli@microsoft.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Michael Kelley <mikelley@microsoft.com> Link: https://lkml.kernel.org/r/20181106040000.27316-1-longli@linuxonhyperv.com
2018-11-05genirq/affinity: Add support for allocating interrupt setsJens Axboe
A driver may have a need to allocate multiple sets of MSI/MSI-X interrupts, and have them appropriately affinitized. Add support for defining a number of sets in the irq_affinity structure, of varying sizes, and get each set affinitized correctly across the machine. [ tglx: Minor changelog tweaks ] Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Keith Busch <keith.busch@intel.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Cc: linux-block@vger.kernel.org Link: https://lkml.kernel.org/r/20181102145951.31979-5-ming.lei@redhat.com
2018-11-05genirq/affinity: Pass first vector to __irq_build_affinity_masks()Ming Lei
No functional change. Prepares for support of allocating and affinitizing sets of interrupts, in which each set of interrupts needs a full two stage spreading. The first vector argument is necessary for this so the affinitizing starts from the first vector of each set. [ tglx: Minor changelog tweaks ] Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: linux-block@vger.kernel.org Cc: Hannes Reinecke <hare@suse.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Sagi Grimberg <sagi@grimberg.me> Link: https://lkml.kernel.org/r/20181102145951.31979-4-ming.lei@redhat.com
2018-11-05genirq/affinity: Move two stage affinity spreading into a helper functionMing Lei
No functional change. Prepares for supporting allocating and affinitizing interrupt sets. [ tglx: Minor changelog tweaks ] Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: linux-block@vger.kernel.org Cc: Hannes Reinecke <hare@suse.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Sagi Grimberg <sagi@grimberg.me> Link: https://lkml.kernel.org/r/20181102145951.31979-3-ming.lei@redhat.com
2018-11-05genirq/affinity: Spread IRQs to all available NUMA nodesLong Li
If the number of NUMA nodes exceeds the number of MSI/MSI-X interrupts which are allocated for a device, the interrupt affinity spreading code fails to spread them across all nodes. The reason is, that the spreading code starts from node 0 and continues up to the number of interrupts requested for allocation. This leaves the nodes past the last interrupt unused. This results in interrupt concentration on the first nodes which violates the assumption of the block layer that all nodes are covered evenly. As a consequence the NUMA nodes above the number of interrupts are all assigned to hardware queue 0 and therefore NUMA node 0, which results in bad performance and has CPU hotplug implications, because queue 0 gets shut down when the last CPU of node 0 is offlined. Go over all NUMA nodes and assign them round-robin to all requested interrupts to solve this. [ tglx: Massaged changelog ] Signed-off-by: Long Li <longli@microsoft.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Cc: Michael Kelley <mikelley@microsoft.com> Link: https://lkml.kernel.org/r/20181102180248.13583-1-longli@linuxonhyperv.com
2018-11-01irq/matrix: Fix memory overallocationMichael Kelley
IRQ_MATRIX_SIZE is the number of longs needed for a bitmap, multiplied by the size of a long, yielding a byte count. But it is used to size an array of longs, which is way more memory than is needed. Change IRQ_MATRIX_SIZE so it is just the number of longs needed and the arrays come out the correct size. Fixes: 2f75d9e1c905 ("genirq: Implement bitmap matrix allocator") Signed-off-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: KY Srinivasan <kys@microsoft.com> Link: https://lkml.kernel.org/r/1541032428-10392-1-git-send-email-mikelley@microsoft.com
2018-10-25Merge branch 'irq-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: "The interrupt brigade came up with the following updates: - Driver for the Marvell System Error Interrupt machinery - Overhaul of the GIC-V3 ITS driver - Small updates and fixes all over the place" * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits) genirq: Fix race on spurious interrupt detection softirq: Fix typo in __do_softirq() comments genirq: Fix grammar s/an /a / irqchip/gic: Unify GIC priority definitions irqchip/gic-v3: Remove acknowledge loop dt-bindings/interrupt-controller: Add documentation for Marvell SEI controller dt-bindings/interrupt-controller: Update Marvell ICU bindings irqchip/irq-mvebu-icu: Add support for System Error Interrupts (SEI) arm64: marvell: Enable SEI driver irqchip/irq-mvebu-sei: Add new driver for Marvell SEI irqchip/irq-mvebu-icu: Support ICU subnodes irqchip/irq-mvebu-icu: Disociate ICU and NSR irqchip/irq-mvebu-icu: Clarify the reset operation of configured interrupts irqchip/irq-mvebu-icu: Fix wrong private data retrieval dt-bindings/interrupt-controller: Fix Marvell ICU length in the example genirq/msi: Allow creation of a tree-based irqdomain for platform-msi dt-bindings: irqchip: renesas-irqc: Document r8a7744 support dt-bindings: irqchip: renesas-irqc: Document R-Car E3 support irqchip/pdc: Setup all edge interrupts as rising edge at GIC irqchip/gic-v3-its: Allow use of LPI tables in reserved memory ...
2018-10-19genirq: Fix race on spurious interrupt detectionLukas Wunner
Commit 1e77d0a1ed74 ("genirq: Sanitize spurious interrupt detection of threaded irqs") made detection of spurious interrupts work for threaded handlers by: a) incrementing a counter every time the thread returns IRQ_HANDLED, and b) checking whether that counter has increased every time the thread is woken. However for oneshot interrupts, the commit unmasks the interrupt before incrementing the counter. If another interrupt occurs right after unmasking but before the counter is incremented, that interrupt is incorrectly considered spurious: time | irq_thread() | irq_thread_fn() | action->thread_fn() | irq_finalize_oneshot() | unmask_threaded_irq() /* interrupt is unmasked */ | | /* interrupt fires, incorrectly deemed spurious */ | | atomic_inc(&desc->threads_handled); /* counter is incremented */ v This is observed with a hi3110 CAN controller receiving data at high volume (from a separate machine sending with "cangen -g 0 -i -x"): The controller signals a huge number of interrupts (hundreds of millions per day) and every second there are about a dozen which are deemed spurious. In theory with high CPU load and the presence of higher priority tasks, the number of incorrectly detected spurious interrupts might increase beyond the 99,900 threshold and cause disablement of the interrupt. In practice it just increments the spurious interrupt count. But that can cause people to waste time investigating it over and over. Fix it by moving the accounting before the invocation of irq_finalize_oneshot(). [ tglx: Folded change log update ] Fixes: 1e77d0a1ed74 ("genirq: Sanitize spurious interrupt detection of threaded irqs") Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Mathias Duckeck <m.duckeck@kunbus.de> Cc: Akshay Bhat <akshay.bhat@timesys.com> Cc: Casey Fitzpatrick <casey.fitzpatrick@timesys.com> Cc: stable@vger.kernel.org # v3.16+ Link: https://lkml.kernel.org/r/1dfd8bbd16163940648045495e3e9698e63b50ad.1539867047.git.lukas@wunner.de
2018-10-09genirq: Fix grammar s/an /a /Geert Uytterhoeven
Fix a grammar mistake in <linux/interrupt.h>. [ mingo: While at it also fix another similar error in another comment as well. ] Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Jiri Kosina <trivial@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20181008111726.26286-1-geert%2Brenesas@glider.be Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-01genirq/debugfs: Reinstate full OF path for domain nameMarc Zyngier
On a DT based system, we use the of_node full name to name the corresponding irq domain. We expect that name to be unique, so so that domains with the same base name won't clash (this happens on multi-node topologies, for example). Since a7e4cfb0a7ca ("of/fdt: only store the device node basename in full_name"), of_node_full_name() lies and only returns the basename. This breaks the above requirement, and we end-up with only a subset of the domains in /sys/kernel/debug/irq/domains. Let's reinstate the feature by using the fancy new %pOF format specifier, which happens to do the right thing. Fixes: a7e4cfb0a7ca ("of/fdt: only store the device node basename in full_name") Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20181001100522.180054-3-marc.zyngier@arm.com
2018-10-01genirq/debugfs: Reset domain debugfs_file on removal of the debugfs fileMarc Zyngier
When removing a debugfs file for a given irq domain, we fail to clear the corresponding field, meaning that the corresponding domain won't be created again if we need to do so. It turns out that this is exactly what irq_domain_update_bus_token does (delete old file, update domain name, recreate file). This doesn't have any impact other than making debug more difficult, but we do value ease of debugging... So clear the debugfs_file field. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20181001100522.180054-2-marc.zyngier@arm.com
2018-09-18irq/matrix: Spread managed interrupts on allocationDou Liyang
Linux spreads out the non managed interrupt across the possible target CPUs to avoid vector space exhaustion. Managed interrupts are treated differently, as for them the vectors are reserved (with guarantee) when the interrupt descriptors are initialized. When the interrupt is requested a real vector is assigned. The assignment logic uses the first CPU in the affinity mask for assignment. If the interrupt has more than one CPU in the affinity mask, which happens when a multi queue device has less queues than CPUs, then doing the same search as for non managed interrupts makes sense as it puts the interrupt on the least interrupt plagued CPU. For single CPU affine vectors that's obviously a NOOP. Restructre the matrix allocation code so it does the 'best CPU' search, add the sanity check for an empty affinity mask and adapt the call site in the x86 vector management code. [ tglx: Added the empty mask check to the core and improved change log ] Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/20180908175838.14450-2-dou_liyang@163.com
2018-09-18irq/matrix: Split out the CPU selection code into a helperDou Liyang
Linux finds the CPU which has the lowest vector allocation count to spread out the non managed interrupts across the possible target CPUs, but does not do so for managed interrupts. Split out the CPU selection code into a helper function for reuse. No functional change. Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/20180908175838.14450-1-dou_liyang@163.com
2018-08-13Merge branch 'irq-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull genirq updates from Thomas Gleixner: "The irq departement provides: - A synchronization fix for free_irq() to synchronize just the removed interrupt thread on shared interrupt lines. - Consolidate the multi low level interrupt entry handling and mvoe it to the generic code instead of adding yet another copy for RISC-V - Refactoring of the ARM LPI allocator and LPI exposure to the hypervisor - Yet another interrupt chip driver for the JZ4725B SoC - Speed up for /proc/interrupts as people seem to love reading this file with high frequency - Miscellaneous fixes and updates" * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) irqchip/gic-v3-its: Make its_lock a raw_spin_lock_t genirq/irqchip: Remove MULTI_IRQ_HANDLER as it's now obselete openrisc: Use the new GENERIC_IRQ_MULTI_HANDLER arm64: Use the new GENERIC_IRQ_MULTI_HANDLER ARM: Convert to GENERIC_IRQ_MULTI_HANDLER irqchip: Port the ARM IRQ drivers to GENERIC_IRQ_MULTI_HANDLER irqchip/gic-v3-its: Reduce minimum LPI allocation to 1 for PCI devices dt-bindings: irqchip: renesas-irqc: Document r8a77980 support dt-bindings: irqchip: renesas-irqc: Document r8a77470 support irqchip/ingenic: Add support for the JZ4725B SoC irqchip/stm32: Add exti0 translation for stm32mp1 genirq: Remove redundant NULL pointer check in __free_irq() irqchip/gic-v3-its: Honor hypervisor enforced LPI range irqchip/gic-v3: Expose GICD_TYPER in the rdist structure irqchip/gic-v3-its: Drop chunk allocation compatibility irqchip/gic-v3-its: Move minimum LPI requirements to individual busses irqchip/gic-v3-its: Use full range of LPIs irqchip/gic-v3-its: Refactor LPI allocator genirq: Synchronize only with single thread on free_irq() genirq: Update code comments wrt recycled thread_mask ...
2018-08-06Merge tag 'irqchip-4.19' of ↵Thomas Gleixner
git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core Pull irqchip updates from Marc Zyngier: - GICv3 ITS LPI allocation revamp - GICv3 support for hypervisor-enforced LPI range - GICv3 ITS conversion to raw spinlock
2018-08-03genirq: Make force irq threading setup more robustThomas Gleixner
The support of force threading interrupts which are set up with both a primary and a threaded handler wreckaged the setup of regular requested threaded interrupts (primary handler == NULL). The reason is that it does not check whether the primary handler is set to the default handler which wakes the handler thread. Instead it replaces the thread handler with the primary handler as it would do with force threaded interrupts which have been requested via request_irq(). So both the primary and the thread handler become the same which then triggers the warnon that the thread handler tries to wakeup a not configured secondary thread. Fortunately this only happens when the driver omits the IRQF_ONESHOT flag when requesting the threaded interrupt, which is normaly caught by the sanity checks when force irq threading is disabled. Fix it by skipping the force threading setup when a regular threaded interrupt is requested. As a consequence the interrupt request which lacks the IRQ_ONESHOT flag is rejected correctly instead of silently wreckaging it. Fixes: 2a1d3ab8986d ("genirq: Handle force threading of irqs with primary and thread handler") Reported-by: Kurt Kanzenbach <kurt.kanzenbach@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Kurt Kanzenbach <kurt.kanzenbach@linutronix.de> Cc: stable@vger.kernel.org
2018-08-03genirq/irqchip: Remove MULTI_IRQ_HANDLER as it's now obseletePalmer Dabbelt
Now that every user of MULTI_IRQ_HANDLER has been convereted over to use GENERIC_IRQ_MULTI_HANDLER remove the references to MULTI_IRQ_HANDLER. Signed-off-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux@armlinux.org.uk Cc: catalin.marinas@arm.com Cc: Will Deacon <will.deacon@arm.com> Cc: jonas@southpole.se Cc: stefan.kristiansson@saunalahti.fi Cc: shorne@gmail.com Cc: jason@lakedaemon.net Cc: marc.zyngier@arm.com Cc: Arnd Bergmann <arnd@arndb.de> Cc: nicolas.pitre@linaro.org Cc: vladimir.murzin@arm.com Cc: keescook@chromium.org Cc: jinb.park7@gmail.com Cc: yamada.masahiro@socionext.com Cc: alexandre.belloni@bootlin.com Cc: pombredanne@nexb.com Cc: Greg KH <gregkh@linuxfoundation.org> Cc: kstewart@linuxfoundation.org Cc: jhogan@kernel.org Cc: mark.rutland@arm.com Cc: ard.biesheuvel@linaro.org Cc: james.morse@arm.com Cc: linux-arm-kernel@lists.infradead.org Cc: openrisc@lists.librecores.org Link: https://lkml.kernel.org/r/20180622170126.6308-6-palmer@sifive.com
2018-07-17genirq: Remove redundant NULL pointer check in __free_irq()RAGHU Halharvi
The NULL pointer check in __free_irq() triggers a 'dereference before NULL pointer check' warning in static code analysis. It turns out that the check is redundant because all callers have a NULL pointer check already. Remove it. Signed-off-by: RAGHU Halharvi <raghuhack78@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20180717102009.7708-1-raghuhack78@gmail.com
2018-06-24genirq: Synchronize only with single thread on free_irq()Lukas Wunner
When pciehp is converted to threaded IRQ handling, removal of unplugged devices below a PCIe hotplug port happens synchronously in the IRQ thread. Removal of devices typically entails a call to free_irq() by their drivers. If those devices share their IRQ with the hotplug port, __free_irq() deadlocks because it calls synchronize_irq() to wait for all hard IRQ handlers as well as all threads sharing the IRQ to finish. Actually it's sufficient to wait only for the IRQ thread of the removed device, so call synchronize_hardirq() to wait for all hard IRQ handlers to finish, but no longer for any threads. Compensate by rearranging the control flow in irq_wait_for_interrupt() such that the device's thread is allowed to run one last time after kthread_stop() has been called. kthread_stop() blocks until the IRQ thread has completed. On completion the IRQ thread clears its oneshot thread_mask bit. This is safe because __free_irq() holds the request_mutex, thereby preventing __setup_irq() from handing out the same oneshot thread_mask bit to a newly requested action. Stack trace for posterity: INFO: task irq/17-pciehp:94 blocked for more than 120 seconds. schedule+0x28/0x80 synchronize_irq+0x6e/0xa0 __free_irq+0x15a/0x2b0 free_irq+0x33/0x70 pciehp_release_ctrl+0x98/0xb0 pcie_port_remove_service+0x2f/0x40 device_release_driver_internal+0x157/0x220 bus_remove_device+0xe2/0x150 device_del+0x124/0x340 device_unregister+0x16/0x60 remove_iter+0x1a/0x20 device_for_each_child+0x4b/0x90 pcie_port_device_remove+0x1e/0x30 pci_device_remove+0x36/0xb0 device_release_driver_internal+0x157/0x220 pci_stop_bus_device+0x7d/0xa0 pci_stop_bus_device+0x3d/0xa0 pci_stop_and_remove_bus_device+0xe/0x20 pciehp_unconfigure_device+0xb8/0x160 pciehp_disable_slot+0x84/0x130 pciehp_ist+0x158/0x190 irq_thread_fn+0x1b/0x50 irq_thread+0x143/0x1a0 kthread+0x111/0x130 Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: linux-pci@vger.kernel.org Link: https://lkml.kernel.org/r/d72b41309f077c8d3bee6cc08ad3662d50b5d22a.1529828292.git.lukas@wunner.de
2018-06-24genirq: Update code comments wrt recycled thread_maskLukas Wunner
Previously a race existed between __free_irq() and __setup_irq() wherein the thread_mask of a just removed action could be handed out to a newly added action and the freed irq thread would then tread on the oneshot mask bit of the newly added irq thread in irq_finalize_oneshot(): time | __free_irq() | raw_spin_lock_irqsave(&desc->lock, flags); | <remove action from linked list> | raw_spin_unlock_irqrestore(&desc->lock, flags); | | __setup_irq() | raw_spin_lock_irqsave(&desc->lock, flags); | <traverse linked list to determine oneshot mask bit> | raw_spin_unlock_irqrestore(&desc->lock, flags); | | irq_thread() of freed irq (__free_irq() waits in synchronize_irq()) | irq_thread_fn() | irq_finalize_oneshot() | raw_spin_lock_irq(&desc->lock); | desc->threads_oneshot &= ~action->thread_mask; | raw_spin_unlock_irq(&desc->lock); v The race was known at least since 2012 when it was documented in a code comment by commit e04268b0effc ("genirq: Remove paranoid warnons and bogus fixups"). The race itself is harmless as nothing touches any of the potentially freed data after synchronize_irq(). In 2017 the race was close by commit 9114014cf4e6 ("genirq: Add mutex to irq desc to serialize request/free_irq()"), apparently inadvertantly so because the race is neither mentioned in the commit message nor was the code comment updated. Make up for that. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: linux-pci@vger.kernel.org Link: https://lkml.kernel.org/r/32fc25aa35ecef4b2692f57687bb7fc2a57230e2.1529828292.git.lukas@wunner.de
2018-06-22genirq: Speedup show_interrupts()Eric Dumazet
Since commit 425a5072dcd1 ("genirq: Free irq_desc with rcu"), show_interrupts() can be switched to rcu locking, which removes possible contention on sparse_irq_lock. The per_cpu count scan and print can be done without holding desc spinlock. And there is no need to call kstat_irqs_cpu() and abuse irq_to_desc() while holding rcu read lock, since desc and desc->kstat_irqs wont disappear or change. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Eric Dumazet <eric.dumazet@gmail.com> Link: https://lkml.kernel.org/r/20180620150332.163320-1-edumazet@google.com
2018-06-22genirq/debugfs: Add missing IRQCHIP_SUPPORTS_LEVEL_MSI debugMarc Zyngier
Debug is missing the IRQCHIP_SUPPORTS_LEVEL_MSI debug entry, making debugfs slightly less useful. Take this opportunity to also add a missing comment in the definition of IRQCHIP_SUPPORTS_LEVEL_MSI. Fixes: 6988e0e0d283 ("genirq/msi: Limit level-triggered MSI to platform devices") Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jason Cooper <jason@lakedaemon.net> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Yang Yingliang <yangyingliang@huawei.com> Cc: Sumit Garg <sumit.garg@linaro.org> Link: https://lkml.kernel.org/r/20180622095254.5906-2-marc.zyngier@arm.com
2018-06-19genirq: Fix editing error in a commentJonathan Neuschäfer
When the comment was reflowed to a wider format, the "*" snuck in. Fixes: ae88a23b32fa ("irq: refactor and clean up the free_irq() code flow") Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20180617124018.25539-1-j.neuschaefer@gmx.net
2018-06-19genirq: Use rcu in kstat_irqs_usr()Eric Dumazet
Jeremy Dorfman identified mutex contention when multiple threads parse /proc/stat concurrently. Since commit 425a5072dcd1 ("genirq: Free irq_desc with rcu"), kstat_irqs_usr() can be switched to rcu locking, which removes this mutex contention. show_interrupts() case will be handled in a separate patch. Reported-by: Jeremy Dorfman <jdorfman@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Willem de Bruijn <willemb@google.com> Link: https://lkml.kernel.org/r/20180618125612.155057-1-edumazet@google.com
2018-06-10Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 updates and fixes from Thomas Gleixner: - Fix the (late) fallout from the vector management rework causing hlist corruption and irq descriptor reference leaks caused by a missing sanity check. The straight forward fix triggered another long standing issue to surface. The pre rework code hid the issue due to being way slower, but now the chance that user space sees an EBUSY error return when updating irq affinities is way higher, though quite a bunch of userspace tools do not handle it properly despite the fact that EBUSY could be returned for at least 10 years. It turned out that the EBUSY return can be avoided completely by utilizing the existing delayed affinity update mechanism for irq remapped scenarios as well. That's a bit more error handling in the kernel, but avoids fruitless fingerpointing discussions with tool developers. - Decouple PHYSICAL_MASK from AMD SME as its going to be required for the upcoming Intel memory encryption support as well. - Handle legacy device ACPI detection properly for newer platforms - Fix the wrong argument ordering in the vector allocation tracepoint - Simplify the IDT setup code for the APIC=n case - Use the proper string helpers in the MTRR code - Remove a stale unused VDSO source file - Convert the microcode update lock to a raw spinlock as its used in atomic context. * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/intel_rdt: Enable CMT and MBM on new Skylake stepping x86/apic/vector: Print APIC control bits in debugfs genirq/affinity: Defer affinity setting if irq chip is busy x86/platform/uv: Use apic_ack_irq() x86/ioapic: Use apic_ack_irq() irq_remapping: Use apic_ack_irq() x86/apic: Provide apic_ack_irq() genirq/migration: Avoid out of line call if pending is not set genirq/generic_pending: Do not lose pending affinity update x86/apic/vector: Prevent hlist corruption and leaks x86/vector: Fix the args of vector_alloc tracepoint x86/idt: Simplify the idt_setup_apic_and_irq_gates() x86/platform/uv: Remove extra parentheses x86/mm: Decouple dynamic __PHYSICAL_MASK from AMD SME x86: Mark native_set_p4d() as __always_inline x86/microcode: Make the late update update_lock a raw lock for RT x86/mtrr: Convert to use strncpy_from_user() helper x86/mtrr: Convert to use match_string() helper x86/vdso: Remove unused file x86/i8237: Register device based on FADT legacy boot flag