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* genirq/affinity: Create affinity mask for single vectorMing Lei2019-08-081-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | Since commit c66d4bd110a1f8 ("genirq/affinity: Add new callback for (re)calculating interrupt sets"), irq_create_affinity_masks() returns NULL in case of single vector. This change has caused regression on some drivers, such as lpfc. The problem is that single vector requests can happen in some generic cases: 1) kdump kernel 2) irq vectors resource is close to exhaustion. If in that situation the affinity mask for a single vector is not created, every caller has to handle the special case. There is no reason why the mask cannot be created, so remove the check for a single vector and create the mask. Fixes: c66d4bd110a1f8 ("genirq/affinity: Add new callback for (re)calculating interrupt sets") Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20190805011906.5020-1-ming.lei@redhat.com
* genirq/affinity: Remove unused argument from [__]irq_build_affinity_masks()Minwoo Im2019-06-121-7/+5
| | | | | | | | | | | | | The *affd argument is neither used in irq_build_affinity_masks() nor __irq_build_affinity_masks(). Remove it. Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Cc: Minwoo Im <minwoo.im@samsung.com> Cc: linux-block@vger.kernel.org Link: https://lkml.kernel.org/r/20190602112117.31839-1-minwoo.im.dev@gmail.com
* genirq/affinity: Remove the leftovers of the original set supportThomas Gleixner2019-02-181-16/+4
| | | | | | | | | | | | | | | | | | | | | | Now that the NVME driver is converted over to the calc_set() callback, the workarounds of the original set support can be removed. 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/20190216172228.689834224@linutronix.de
* genirq/affinity: Add new callback for (re)calculating interrupt setsMing Lei2019-02-181-18/+44
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 is required in struct irq_affinity, which can be invoked by the core code. The callback gets the number of available interupts as an argument, so the driver can calculate the corresponding number and size of interrupt sets. 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', but for the callback to be able to modify the data in the struct it's required to remove the 'const' qualifier. Add the optional callback to struct irq_affinity, which allows drivers to recalculate the number and size of interrupt sets and remove the 'const' qualifier. For simple invocations, which do not supply a callback, a default callback is installed, which just sets nr_sets to 1 and transfers the number of spreadable vectors to the set_size array at index 0. This is for now guarded by a check for nr_sets != 0 to keep the NVME driver working until it is converted to the callback mechanism. To make sure that the driver configuration is correct under all circumstances the callback is invoked even when there are no interrupts for queues left, i.e. the pre/post requirements already exhaust the numner of available interrupts. At the PCI layer irq_create_affinity_masks() has to be invoked even for the case where the legacy interrupt is used. That ensures that the callback is invoked and the device driver can adjust to that situation. [ tglx: Fixed the simple case (no sets required). Moved the sanity check for nr_sets after the invocation of the callback so it catches broken drivers. 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/20190216172228.512444498@linutronix.de
* genirq/affinity: Store interrupt sets size in struct irq_affinityMing Lei2019-02-181-4/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* genirq/affinity: Code consolidationThomas Gleixner2019-02-181-29/+27
| | | | | | | | | | | | | | | | | | | | | | | | 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
* genirq/affinity: Move allocation of 'node_to_cpumask' to ↵Ming Lei2019-02-101-14/+13
| | | | | | | | | | | | | | | | | | | | | 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
* genirq/affinity: Add is_managed to struct irq_affinity_descDou Liyang2018-12-191-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* genirq/core: Introduce struct irq_affinity_descDou Liyang2018-12-191-10/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* genirq/affinity: Remove excess indentationThomas Gleixner2018-12-191-11/+11
| | | | | | Plus other coding style issues which stood out while staring at that code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* genirq/affinity: Add support for allocating interrupt setsJens Axboe2018-11-051-23/+54
| | | | | | | | | | | | | | | | | | | | | 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
* genirq/affinity: Pass first vector to __irq_build_affinity_masks()Ming Lei2018-11-051-9/+11
| | | | | | | | | | | | | | | | | | | | | 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
* genirq/affinity: Move two stage affinity spreading into a helper functionMing Lei2018-11-051-36/+56
| | | | | | | | | | | | | | | | | 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
* genirq/affinity: Spread IRQs to all available NUMA nodesLong Li2018-11-051-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* genirq/affinity: Spread irq vectors among present CPUs as far as possibleMing Lei2018-04-061-6/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 84676c1f21 ("genirq/affinity: assign vectors to all possible CPUs") tried to spread the interrupts accross all possible CPUs to make sure that in case of phsyical hotplug (e.g. virtualization) the CPUs which get plugged in after the device was initialized are targeted by a hardware queue and the corresponding interrupt. This has a downside in cases where the ACPI tables claim that there are more possible CPUs than present CPUs and the number of interrupts to spread out is smaller than the number of possible CPUs. These bogus ACPI tables are unfortunately not uncommon. In such a case the vector spreading algorithm assigns interrupts to CPUs which can never be utilized and as a consequence these interrupts are unused instead of being mapped to present CPUs. As a result the performance of the device is suboptimal. To fix this spread the interrupt vectors in two stages: 1) Spread as many interrupts as possible among the present CPUs 2) Spread the remaining vectors among non present CPUs On a 8 core system, where CPU 0-3 are present and CPU 4-7 are not present, for a device with 4 queues the resulting interrupt affinity is: 1) Before 84676c1f21 ("genirq/affinity: assign vectors to all possible CPUs") irq 39, cpu list 0 irq 40, cpu list 1 irq 41, cpu list 2 irq 42, cpu list 3 2) With 84676c1f21 ("genirq/affinity: assign vectors to all possible CPUs") irq 39, cpu list 0-2 irq 40, cpu list 3-4,6 irq 41, cpu list 5 irq 42, cpu list 7 3) With the refined vector spread applied: irq 39, cpu list 0,4 irq 40, cpu list 1,6 irq 41, cpu list 2,5 irq 42, cpu list 3,7 On a 8 core system, where all CPUs are present the resulting interrupt affinity for the 4 queues is: irq 39, cpu list 0,1 irq 40, cpu list 2,3 irq 41, cpu list 4,5 irq 42, cpu list 6,7 This is independent of the number of CPUs which are online at the point of initialization because in such a system the offline CPUs can be easily onlined afterwards, while in non-present CPUs need to be plugged physically or virtually which requires external interaction. The downside of this approach is that in case of physical hotplug the interrupt vector spreading might be suboptimal when CPUs 4-7 are physically plugged. Suboptimal from a NUMA point of view and due to the single target nature of interrupt affinities the later plugged CPUs might not be targeted by interrupts at all. Though, physical hotplug systems are not the common case while the broken ACPI table disease is wide spread. So it's preferred to have as many interrupts as possible utilized at the point where the device is initialized. Block multi-queue devices like NVME create a hardware queue per possible CPU, so the goal of commit 84676c1f21 to assign one interrupt vector per possible CPU is still achieved even with physical/virtual hotplug. [ tglx: Changed from online to present CPUs for the first spreading stage, renamed variables for readability sake, added comments and massaged changelog ] Reported-by: Laurence Oberman <loberman@redhat.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: linux-block@vger.kernel.org Cc: Christoph Hellwig <hch@infradead.org> Link: https://lkml.kernel.org/r/20180308105358.1506-5-ming.lei@redhat.com
* genirq/affinity: Allow irq spreading from a given starting pointMing Lei2018-04-061-15/+20
| | | | | | | | | | | | | | | | | | To support two stage irq vector spreading, it's required to add a starting point to the spreading function. No functional change, just preparatory work for the actual two stage change. [ tglx: Renamed variables, tidied up the code and massaged changelog ] Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: linux-block@vger.kernel.org Cc: Laurence Oberman <loberman@redhat.com> Cc: Christoph Hellwig <hch@infradead.org> Link: https://lkml.kernel.org/r/20180308105358.1506-4-ming.lei@redhat.com
* genirq/affinity: Move actual irq vector spreading into a helper functionMing Lei2018-04-061-42/+55
| | | | | | | | | | | | | | | No functional change, just prepare for converting to 2-stage irq vector spreading. Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: linux-block@vger.kernel.org Cc: Laurence Oberman <loberman@redhat.com> Cc: Christoph Hellwig <hch@infradead.org> Link: https://lkml.kernel.org/r/20180308105358.1506-3-ming.lei@redhat.com
* genirq/affinity: Rename *node_to_possible_cpumask as *node_to_cpumaskMing Lei2018-04-061-13/+13
| | | | | | | | | | | | | | | | | The following patches will introduce two stage irq spreading for improving irq spread on all possible CPUs. No functional change. Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: linux-block@vger.kernel.org Cc: Laurence Oberman <loberman@redhat.com> Cc: Christoph Hellwig <hch@infradead.org> Link: https://lkml.kernel.org/r/20180308105358.1506-2-ming.lei@redhat.com
* genirq/affinity: Don't return with empty affinity masks on errorThomas Gleixner2018-04-061-7/+8
| | | | | | | | | | | | | | When the allocation of node_to_possible_cpumask fails, then irq_create_affinity_masks() returns with a pointer to the empty affinity masks array, which will cause malfunction. Reorder the allocations so the masks array allocation comes last and every failure path returns NULL. Fixes: 9a0ef98e186d ("genirq/affinity: Assign vectors to all present CPUs") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Christoph Hellwig <hch@infradead.org> Cc: Ming Lei <ming.lei@redhat.com>
* genirq/affinity: assign vectors to all possible CPUsChristoph Hellwig2018-01-121-15/+15
| | | | | | | | | | | | | | | | | | | Currently we assign managed interrupt vectors to all present CPUs. This works fine for systems were we only online/offline CPUs. But in case of systems that support physical CPU hotplug (or the virtualized version of it) this means the additional CPUs covered for in the ACPI tables or on the command line are not catered for. To fix this we'd either need to introduce new hotplug CPU states just for this case, or we can start assining vectors to possible but not present CPUs. Reported-by: Christian Borntraeger <borntraeger@de.ibm.com> Tested-by: Christian Borntraeger <borntraeger@de.ibm.com> Tested-by: Stefan Haberland <sth@linux.vnet.ibm.com> Fixes: 4b855ad37194 ("blk-mq: Create hctx for each present CPU") Cc: linux-kernel@vger.kernel.org Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman2017-11-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge tag 'pci-v4.13-changes' of ↵Linus Torvalds2017-07-081-1/+12
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: - add sysfs max_link_speed/width, current_link_speed/width (Wong Vee Khee) - make host bridge IRQ mapping much more generic (Matthew Minter, Lorenzo Pieralisi) - convert most drivers to pci_scan_root_bus_bridge() (Lorenzo Pieralisi) - mutex sriov_configure() (Jakub Kicinski) - mutex pci_error_handlers callbacks (Christoph Hellwig) - split ->reset_notify() into ->reset_prepare()/reset_done() (Christoph Hellwig) - support multiple PCIe portdrv interrupts for MSI as well as MSI-X (Gabriele Paoloni) - allocate MSI/MSI-X vector for Downstream Port Containment (Gabriele Paoloni) - fix MSI IRQ affinity pre/post/min_vecs issue (Michael Hernandez) - test INTx masking during enumeration, not at run-time (Piotr Gregor) - avoid using device_may_wakeup() for runtime PM (Rafael J. Wysocki) - restore the status of PCI devices across hibernation (Chen Yu) - keep parent resources that start at 0x0 (Ard Biesheuvel) - enable ECRC only if device supports it (Bjorn Helgaas) - restore PRI and PASID state after Function-Level Reset (CQ Tang) - skip DPC event if device is not present (Keith Busch) - check domain when matching SMBIOS info (Sujith Pandel) - mark Intel XXV710 NIC INTx masking as broken (Alex Williamson) - avoid AMD SB7xx EHCI USB wakeup defect (Kai-Heng Feng) - work around long-standing Macbook Pro poweroff issue (Bjorn Helgaas) - add Switchtec "running" status flag (Logan Gunthorpe) - fix dra7xx incorrect RW1C IRQ register usage (Arvind Yadav) - modify xilinx-nwl IRQ chip for legacy interrupts (Bharat Kumar Gogada) - move VMD SRCU cleanup after bus, child device removal (Jon Derrick) - add Faraday clock handling (Linus Walleij) - configure Rockchip MPS and reorganize (Shawn Lin) - limit Qualcomm TLP size to 2K (hardware issue) (Srinivas Kandagatla) - support Tegra MSI 64-bit addressing (Thierry Reding) - use Rockchip normal (not privileged) register bank (Shawn Lin) - add HiSilicon Kirin SoC PCIe controller driver (Xiaowei Song) - add Sigma Designs Tango SMP8759 PCIe controller driver (Marc Gonzalez) - add MediaTek PCIe host controller support (Ryder Lee) - add Qualcomm IPQ4019 support (John Crispin) - add HyperV vPCI protocol v1.2 support (Jork Loeser) - add i.MX6 regulator support (Quentin Schulz) * tag 'pci-v4.13-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (113 commits) PCI: tango: Add Sigma Designs Tango SMP8759 PCIe host bridge support PCI: Add DT binding for Sigma Designs Tango PCIe controller PCI: rockchip: Use normal register bank for config accessors dt-bindings: PCI: Add documentation for MediaTek PCIe PCI: Remove __pci_dev_reset() and pci_dev_reset() PCI: Split ->reset_notify() method into ->reset_prepare() and ->reset_done() PCI: xilinx: Make of_device_ids const PCI: xilinx-nwl: Modify IRQ chip for legacy interrupts PCI: vmd: Move SRCU cleanup after bus, child device removal PCI: vmd: Correct comment: VMD domains start at 0x10000, not 0x1000 PCI: versatile: Add local struct device pointers PCI: tegra: Do not allocate MSI target memory PCI: tegra: Support MSI 64-bit addressing PCI: rockchip: Use local struct device pointer consistently PCI: rockchip: Check for clk_prepare_enable() errors during resume MAINTAINERS: Remove Wenrui Li as Rockchip PCIe driver maintainer PCI: rockchip: Configure RC's MPS setting PCI: rockchip: Reconfigure configuration space header type PCI: rockchip: Split out rockchip_pcie_cfg_configuration_accesses() PCI: rockchip: Move configuration accesses into rockchip_pcie_cfg_atu() ...
| * PCI/MSI: Ignore affinity if pre/post vector count is more than min_vecsMichael Hernandez2017-05-221-1/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | min_vecs is the minimum amount of vectors needed to operate in MSI-X mode which may just include the vectors that don't need affinity. Disabling affinity settings causes the qla2xxx driver scsi_add_host() to fail when blk_mq is enabled as the blk_mq_pci_map_queues() expects affinity masks on each vector. Fixes: dfef358bd1be ("PCI/MSI: Don't apply affinity if there aren't enough vectors left") Signed-off-by: Michael Hernandez <michael.hernandez@cavium.com> Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: stable@vger.kernel.org # v4.10+
* | genirq/affinity: Assign vectors to all present CPUsChristoph Hellwig2017-06-221-13/+63
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | Currently the irq vector spread algorithm is restricted to online CPUs, which ties the IRQ mapping to the currently online devices and doesn't deal nicely with the fact that CPUs could come and go rapidly due to e.g. power management. Instead assign vectors to all present CPUs to avoid this churn. Build a map of all possible CPUs for a given node, as the architectures only provide a map of all onlines CPUs. Do this dynamically on each call for the vector assingments, which is a bit suboptimal and could be optimized in the future by provinding a mapping from the arch code. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: linux-block@vger.kernel.org Cc: Sagi Grimberg <sagi@grimberg.me> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: linux-nvme@lists.infradead.org Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20170603140403.27379-5-hch@lst.de
* genirq/affinity: Fix calculating vectors to assignKeith Busch2017-04-201-1/+1
| | | | | | | | | | | | | | The vectors_per_node is calculated from the remaining available vectors. The current vector starts after pre_vectors, so we need to subtract that from the current to properly account for the number of remaining vectors to assign. Fixes: 3412386b531 ("irq/affinity: Fix extra vecs calculation") Reported-by: Andrei Vagin <avagin@virtuozzo.com> Signed-off-by: Keith Busch <keith.busch@intel.com> Link: http://lkml.kernel.org/r/1492645870-13019-1-git-send-email-keith.busch@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* irq/affinity: Fix extra vecs calculationKeith Busch2017-04-131-1/+1
| | | | | | | | | | | | | | This fixes a math error calculating the extra_vecs. The error assumed only 1 cpu per vector, but the value needs to account for the actual number of cpus per vector in order to get the correct remainder for extra CPU assignment. Fixes: 7bf8222b9bd0 ("irq/affinity: Fix CPU spread for unbalanced nodes") Reported-by: Xiaolong Ye <xiaolong.ye@intel.com> Signed-off-by: Keith Busch <keith.busch@intel.com> Link: http://lkml.kernel.org/r/1492104492-19943-1-git-send-email-keith.busch@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* irq/affinity: Fix CPU spread for unbalanced nodesKeith Busch2017-04-041-9/+11
| | | | | | | | | | | | | | | | | | | | | | | The irq_create_affinity_masks routine is responsible for assigning a number of interrupt vectors to CPUs. The optimal assignemnet will spread requested vectors to all CPUs, with the fewest CPUs sharing a vector. The algorithm may fail to assign some vectors to any CPUs if a node's CPU count is lower than the average number of vectors per node. These vectors are unusable and create an un-optimal spread. Recalculate the number of vectors to assign at each node iteration by using the remaining number of vectors and nodes to be assigned, not exceeding the number of CPUs in that node. This will guarantee that every CPU is assigned at least one vector. Signed-off-by: Keith Busch <keith.busch@intel.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: linux-nvme@lists.infradead.org Link: http://lkml.kernel.org/r/1491247553-7603-1-git-send-email-keith.busch@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* genirq/affinity: Fix node generation from cpumaskGuilherme G. Piccoli2016-12-151-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 34c3d9819fda ("genirq/affinity: Provide smarter irq spreading infrastructure") introduced a better IRQ spreading mechanism, taking account of the available NUMA nodes in the machine. Problem is that the algorithm of retrieving the nodemask iterates "linearly" based on the number of online nodes - some architectures present non-linear node distribution among the nodemask, like PowerPC. If this is the case, the algorithm lead to a wrong node count number and therefore to a bad/incomplete IRQ affinity distribution. For example, this problem were found in a machine with 128 CPUs and two nodes, namely nodes 0 and 8 (instead of 0 and 1, if it was linearly distributed). This led to a wrong affinity distribution which then led to a bad mq allocation for nvme driver. Finally, we take the opportunity to fix a comment regarding the affinity distribution when we have _more_ nodes than vectors. Fixes: 34c3d9819fda ("genirq/affinity: Provide smarter irq spreading infrastructure") Reported-by: Gabriel Krisman Bertazi <gabriel@krisman.be> Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Gabriel Krisman Bertazi <gabriel@krisman.be> Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Cc: linux-pci@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: hch@lst.de Link: http://lkml.kernel.org/r/1481738472-2671-1-git-send-email-gpiccoli@linux.vnet.ibm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* genirq/affinity: Use default affinity mask for reserved vectorsThomas Gleixner2016-11-161-2/+2
| | | | | | | | | | | | | | The reserved vectors at the beginning and the end of the vector space get cpu_possible_mask assigned as their affinity mask. All other non-auto affine interrupts get the default irq affinity mask assigned. Using cpu_possible_mask breaks that rule. Treat them like any other interrupt and use irq_default_affinity as target mask. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Christoph Hellwig <hch@lst.de>
* genirq/affinity: Take reserved vectors into account when spreading irqsChristoph Hellwig2016-11-161-3/+5
| | | | | | | | | | | | | | | | | | | The recent addition of reserved vectors at the beginning or the end of the vector space did not take the reserved vectors at the beginning into account for the various loop exit conditions. As a consequence the last vectors of the spread area are not included into the spread algorithm and are treated like the reserved vectors at the end of the vector space and get the default affinity mask assigned. Sum up the affinity vectors and the reserved vectors at the beginning and use the sum as exit condition. [ tglx: Fixed all conditions instead of only one and massaged changelog ] Signed-off-by: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/1479201178-29604-2-git-send-email-hch@lst.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* genirq/affinity: Handle pre/post vectors in irq_create_affinity_masks()Christoph Hellwig2016-11-091-21/+25
| | | | | | | | | | | | | | | | | | | Only calculate the affinity for the main I/O vectors, and skip the pre or post vectors specified by struct irq_affinity. Also remove the irq_affinity cpumask argument that has never been used. If we ever need it in the future we can pass it through struct irq_affinity. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Jens Axboe <axboe@kernel.dk> Cc: linux-block@vger.kernel.org Cc: linux-pci@vger.kernel.org Link: http://lkml.kernel.org/r/1478654107-7384-4-git-send-email-hch@lst.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* genirq/affinity: Handle pre/post vectors in irq_calc_affinity_vectors()Christoph Hellwig2016-11-091-14/+10
| | | | | | | | | | | | | | | | | Only calculate the affinity for the main I/O vectors, and skip the pre or post vectors specified by struct irq_affinity. Also remove the irq_affinity cpumask argument that has never been used. If we ever need it in the future we can pass it through struct irq_affinity. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Acked-by: Jens Axboe <axboe@kernel.dk> Cc: linux-block@vger.kernel.org Cc: linux-pci@vger.kernel.org Link: http://lkml.kernel.org/r/1478654107-7384-3-git-send-email-hch@lst.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* genirq/affinity: Remove old irq spread infrastructureThomas Gleixner2016-09-141-58/+0
| | | | | | | | | | | | | | No more users. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Christoph Hellwig <hch@lst.de> Cc: axboe@fb.com Cc: keith.busch@intel.com Cc: agordeev@redhat.com Cc: linux-block@vger.kernel.org Link: http://lkml.kernel.org/r/1473862739-15032-5-git-send-email-hch@lst.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* genirq/affinity: Provide smarter irq spreading infrastructureThomas Gleixner2016-09-141-0/+149
| | | | | | | | | | | | | | | | | | | | The current irq spreading infrastructure is just looking at a cpumask and tries to spread the interrupts over the mask. Thats suboptimal as it does not take numa nodes into account. Change the logic so the interrupts are spread across numa nodes and inside the nodes. If there are more cpus than vectors per node, then we set the affinity to several cpus. If HT siblings are available we take that into account and try to set all siblings to a single vector. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Christoph Hellwig <hch@lst.de> Cc: axboe@fb.com Cc: keith.busch@intel.com Cc: agordeev@redhat.com Cc: linux-block@vger.kernel.org Link: http://lkml.kernel.org/r/1473862739-15032-3-git-send-email-hch@lst.de
* genirq/affinity: Use get/put_online_cpus around cpumask operationsChristoph Hellwig2016-08-221-0/+2
| | | | | | | | | | | Without locking out CPU mask operations we might end up with an inconsistent view of the cpumask in the function. Fixes: 5e385a6ef31f: "genirq: Add a helper to spread an affinity mask for MSI/MSI-X vectors" Signed-off-by: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/1470924405-25728-1-git-send-email-hch@lst.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* genirq: Add a helper to spread an affinity mask for MSI/MSI-X vectorsChristoph Hellwig2016-07-041-0/+61
This is lifted from the blk-mq code and adopted to use the affinity mask concept just introduced in the irq handling code. It tries to keep the algorithm the same as the one current used by blk-mq, but improvements like assining vectors on a per-node basis instead of just per sibling are possible with this simple move and refactoring. Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: linux-block@vger.kernel.org Cc: linux-pci@vger.kernel.org Cc: linux-nvme@lists.infradead.org Cc: axboe@fb.com Cc: agordeev@redhat.com Link: http://lkml.kernel.org/r/1467621574-8277-7-git-send-email-hch@lst.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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