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* 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>