| Message ID | 20241115-refactor-blk-affinity-helpers-v5-4-c472afd84d9f@kernel.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | blk: refactor queue affinity helpers | expand |
On Fri, Nov 15, 2024 at 05:37:48PM +0100, Daniel Wagner wrote: > blk_mq_pci_map_queues and blk_mq_virtio_map_queues will create a CPU to > hardware queue mapping based on affinity information. These two function > share common code and only differ on how the affinity information is > retrieved. Also, those functions are located in the block subsystem > where it doesn't really fit in. They are virtio and pci subsystem > specific. > > Thus introduce provide a generic mapping function which uses the > irq_get_affinity callback from bus_type. > > Originally idea from Ming Lei <ming.lei@redhat.com> > > Reviewed-by: Christoph Hellwig <hch@lst.de> > Reviewed-by: Hannes Reinecke <hare@suse.de> > Signed-off-by: Daniel Wagner <wagi@kernel.org> Reviewed-by: Ming Lei <ming.lei@redhat.com>
On 15/11/2024 16:37, Daniel Wagner wrote: > blk_mq_pci_map_queues and blk_mq_virtio_map_queues will create a CPU to > hardware queue mapping based on affinity information. These two function > share common code and only differ on how the affinity information is > retrieved. Also, those functions are located in the block subsystem > where it doesn't really fit in. They are virtio and pci subsystem > specific. > > Thus introduce provide a generic mapping function which uses the > irq_get_affinity callback from bus_type. > > Originally idea from Ming Lei <ming.lei@redhat.com> > > Reviewed-by: Christoph Hellwig <hch@lst.de> > Reviewed-by: Hannes Reinecke <hare@suse.de> > Signed-off-by: Daniel Wagner <wagi@kernel.org> Just a couple of styling queries/comments, below: Reviewed-by: John Garry <john.g.garry@oracle.com> > --- > block/blk-mq-cpumap.c | 37 +++++++++++++++++++++++++++++++++++++ > include/linux/blk-mq.h | 2 ++ > 2 files changed, 39 insertions(+) > > diff --git a/block/blk-mq-cpumap.c b/block/blk-mq-cpumap.c > index 9638b25fd52124f0173e968ebdca5f1fe0b42ad9..0b65ffa5a183cc8e6697df4a16748eff15bfa8b3 100644 > --- a/block/blk-mq-cpumap.c > +++ b/block/blk-mq-cpumap.c > @@ -11,6 +11,7 @@ > #include <linux/smp.h> > #include <linux/cpu.h> > #include <linux/group_cpus.h> > +#include <linux/device/bus.h> > > #include "blk.h" > #include "blk-mq.h" > @@ -54,3 +55,39 @@ int blk_mq_hw_queue_to_node(struct blk_mq_queue_map *qmap, unsigned int index) > > return NUMA_NO_NODE; > } > + > +/** > + * blk_mq_map_hw_queues - Create CPU to hardware queue mapping > + * @qmap: CPU to hardware queue map. > + * @dev: The device to map queues. > + * @offset: Queue offset to use for the device. supernit: maybe no '.' > + * > + * Create a CPU to hardware queue mapping in @qmap. The struct bus_type > + * irq_get_affinity callback will be used to retrieve the affinity. > + */ > +void blk_mq_map_hw_queues(struct blk_mq_queue_map *qmap, > + struct device *dev, unsigned int offset) > + > +{ > + const struct cpumask *mask; > + unsigned int queue, cpu; > + > + if (!dev->bus->irq_get_affinity) > + goto fallback; > + > + for (queue = 0; queue < qmap->nr_queues; queue++) { > + mask = dev->bus->irq_get_affinity(dev, queue + offset); > + if (!mask) > + goto fallback; > + > + for_each_cpu(cpu, mask) > + qmap->mq_map[cpu] = qmap->queue_offset + queue; > + } > + > + return; > + > +fallback: > + WARN_ON_ONCE(qmap->nr_queues > 1); > + blk_mq_clear_mq_map(qmap); > +} > +EXPORT_SYMBOL_GPL(blk_mq_map_hw_queues); is there still a blank line at the bottom of the file? > diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h > index 2035fad3131fb60781957095ce8a3a941dd104be..05f544a9ed873d2f96d72c18e124c94146f6943f 100644 > --- a/include/linux/blk-mq.h > +++ b/include/linux/blk-mq.h > @@ -923,6 +923,8 @@ void blk_mq_unfreeze_queue_non_owner(struct request_queue *q); > void blk_freeze_queue_start_non_owner(struct request_queue *q); > > void blk_mq_map_queues(struct blk_mq_queue_map *qmap); > +void blk_mq_map_hw_queues(struct blk_mq_queue_map *qmap, > + struct device *dev, unsigned int offset); > void blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, int nr_hw_queues); > > void blk_mq_quiesce_queue_nowait(struct request_queue *q); >
diff --git a/block/blk-mq-cpumap.c b/block/blk-mq-cpumap.c index 9638b25fd52124f0173e968ebdca5f1fe0b42ad9..0b65ffa5a183cc8e6697df4a16748eff15bfa8b3 100644 --- a/block/blk-mq-cpumap.c +++ b/block/blk-mq-cpumap.c @@ -11,6 +11,7 @@ #include <linux/smp.h> #include <linux/cpu.h> #include <linux/group_cpus.h> +#include <linux/device/bus.h> #include "blk.h" #include "blk-mq.h" @@ -54,3 +55,39 @@ int blk_mq_hw_queue_to_node(struct blk_mq_queue_map *qmap, unsigned int index) return NUMA_NO_NODE; } + +/** + * blk_mq_map_hw_queues - Create CPU to hardware queue mapping + * @qmap: CPU to hardware queue map. + * @dev: The device to map queues. + * @offset: Queue offset to use for the device. + * + * Create a CPU to hardware queue mapping in @qmap. The struct bus_type + * irq_get_affinity callback will be used to retrieve the affinity. + */ +void blk_mq_map_hw_queues(struct blk_mq_queue_map *qmap, + struct device *dev, unsigned int offset) + +{ + const struct cpumask *mask; + unsigned int queue, cpu; + + if (!dev->bus->irq_get_affinity) + goto fallback; + + for (queue = 0; queue < qmap->nr_queues; queue++) { + mask = dev->bus->irq_get_affinity(dev, queue + offset); + if (!mask) + goto fallback; + + for_each_cpu(cpu, mask) + qmap->mq_map[cpu] = qmap->queue_offset + queue; + } + + return; + +fallback: + WARN_ON_ONCE(qmap->nr_queues > 1); + blk_mq_clear_mq_map(qmap); +} +EXPORT_SYMBOL_GPL(blk_mq_map_hw_queues); diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 2035fad3131fb60781957095ce8a3a941dd104be..05f544a9ed873d2f96d72c18e124c94146f6943f 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -923,6 +923,8 @@ void blk_mq_unfreeze_queue_non_owner(struct request_queue *q); void blk_freeze_queue_start_non_owner(struct request_queue *q); void blk_mq_map_queues(struct blk_mq_queue_map *qmap); +void blk_mq_map_hw_queues(struct blk_mq_queue_map *qmap, + struct device *dev, unsigned int offset); void blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, int nr_hw_queues); void blk_mq_quiesce_queue_nowait(struct request_queue *q);