| Message ID | 20240913-refactor-blk-affinity-helpers-v1-1-8e058f77af12@suse.de |
|---|---|
| State | New |
| Headers | show |
| Series | EDITME: blk: refactor queue affinity helpers | expand |
On Fri, Sep 13, 2024 at 09:41:59AM +0200, Daniel Wagner wrote: > From: Ming Lei <ming.lei@redhat.com> > > 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 code which only differs on how the affinity information > is retrieved. Also there is the hisi_sas which open codes the same loop. > > Thus introduce a new helper function for creating these mappings which > takes an callback function for fetching the affinity mask. Also > introduce common helper function for PCI and virtio devices to retrieve > affinity masks. > diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c > index e3a49f66982d..84f9c16b813b 100644 > --- a/drivers/pci/pci.c > +++ b/drivers/pci/pci.c > @@ -6370,6 +6370,26 @@ int pci_set_vga_state(struct pci_dev *dev, bool decode, > return 0; > } > > +#ifdef CONFIG_BLK_MQ_PCI > +/** > + * pci_get_blk_mq_affinity - get affinity mask queue mapping for PCI device > + * @dev_data: Pointer to struct pci_dev. > + * @offset: Offset to use for the pci irq vector > + * @queue: Queue index > + * > + * This function returns for a queue the affinity mask for a PCI device. > + * It is usually used as callback for blk_mq_hctx_map_queues(). > + */ > +const struct cpumask *pci_get_blk_mq_affinity(void *dev_data, int offset, > + int queue) > +{ > + struct pci_dev *pdev = dev_data; > + > + return pci_irq_get_affinity(pdev, offset + queue); > +} > +EXPORT_SYMBOL_GPL(pci_get_blk_mq_affinity); > +#endif IMO this doesn't really fit well in drivers/pci since it doesn't add any PCI-specific knowledge or require any PCI core internals, and the parameters are blk-specific. I don't object to the code, but it seems like it could go somewhere in block/? Bjorn
On 9/13/24 10:26 AM, Bjorn Helgaas wrote: > On Fri, Sep 13, 2024 at 09:41:59AM +0200, Daniel Wagner wrote: >> From: Ming Lei <ming.lei@redhat.com> >> >> 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 code which only differs on how the affinity information >> is retrieved. Also there is the hisi_sas which open codes the same loop. >> >> Thus introduce a new helper function for creating these mappings which >> takes an callback function for fetching the affinity mask. Also >> introduce common helper function for PCI and virtio devices to retrieve >> affinity masks. > >> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c >> index e3a49f66982d..84f9c16b813b 100644 >> --- a/drivers/pci/pci.c >> +++ b/drivers/pci/pci.c >> @@ -6370,6 +6370,26 @@ int pci_set_vga_state(struct pci_dev *dev, bool decode, >> return 0; >> } >> >> +#ifdef CONFIG_BLK_MQ_PCI >> +/** >> + * pci_get_blk_mq_affinity - get affinity mask queue mapping for PCI device >> + * @dev_data: Pointer to struct pci_dev. >> + * @offset: Offset to use for the pci irq vector >> + * @queue: Queue index >> + * >> + * This function returns for a queue the affinity mask for a PCI device. >> + * It is usually used as callback for blk_mq_hctx_map_queues(). >> + */ >> +const struct cpumask *pci_get_blk_mq_affinity(void *dev_data, int offset, >> + int queue) >> +{ >> + struct pci_dev *pdev = dev_data; >> + >> + return pci_irq_get_affinity(pdev, offset + queue); >> +} >> +EXPORT_SYMBOL_GPL(pci_get_blk_mq_affinity); >> +#endif > > IMO this doesn't really fit well in drivers/pci since it doesn't add > any PCI-specific knowledge or require any PCI core internals, and the > parameters are blk-specific. I don't object to the code, but it seems > like it could go somewhere in block/? Probably not a bad idea. Unrelated to that topic, but Daniel, all your email gets marked as spam. I didn't see your series before this reply. This has been common recently for people that haven't kept up with kernel.org changes, please check for smtp changes there.
diff --git a/block/blk-mq-cpumap.c b/block/blk-mq-cpumap.c index 9638b25fd521..c4993c0f822e 100644 --- a/block/blk-mq-cpumap.c +++ b/block/blk-mq-cpumap.c @@ -54,3 +54,38 @@ int blk_mq_hw_queue_to_node(struct blk_mq_queue_map *qmap, unsigned int index) return NUMA_NO_NODE; } + +/** + * blk_mq_hctx_map_queues - Create CPU to hardware queue mapping + * @qmap: CPU to hardware queue map. + * @dev_off: Offset to use for the device. + * @dev_data: Device data passed to get_queue_affinity(). + * @get_queue_affinity: Callback to retrieve queue affinity. + * + * Create a CPU to hardware queue mapping in @qmap. For each queue + * @get_queue_affinity will be called to retrieve the affinity for given + * queue. + */ +void blk_mq_hctx_map_queues(struct blk_mq_queue_map *qmap, + void *dev_data, int dev_off, + get_queue_affinty_fn *get_queue_affinity) +{ + const struct cpumask *mask; + unsigned int queue, cpu; + + for (queue = 0; queue < qmap->nr_queues; queue++) { + mask = get_queue_affinity(dev_data, dev_off, queue); + 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_hctx_map_queues); diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index e3a49f66982d..84f9c16b813b 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -6370,6 +6370,26 @@ int pci_set_vga_state(struct pci_dev *dev, bool decode, return 0; } +#ifdef CONFIG_BLK_MQ_PCI +/** + * pci_get_blk_mq_affinity - get affinity mask queue mapping for PCI device + * @dev_data: Pointer to struct pci_dev. + * @offset: Offset to use for the pci irq vector + * @queue: Queue index + * + * This function returns for a queue the affinity mask for a PCI device. + * It is usually used as callback for blk_mq_hctx_map_queues(). + */ +const struct cpumask *pci_get_blk_mq_affinity(void *dev_data, int offset, + int queue) +{ + struct pci_dev *pdev = dev_data; + + return pci_irq_get_affinity(pdev, offset + queue); +} +EXPORT_SYMBOL_GPL(pci_get_blk_mq_affinity); +#endif + #ifdef CONFIG_ACPI bool pci_pr3_present(struct pci_dev *pdev) { diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c index a9b93e99c23a..21667309ca9a 100644 --- a/drivers/virtio/virtio.c +++ b/drivers/virtio/virtio.c @@ -592,6 +592,37 @@ int virtio_device_restore(struct virtio_device *dev) EXPORT_SYMBOL_GPL(virtio_device_restore); #endif +const struct cpumask *virtio_get_vq_affinity(struct virtio_device *dev, + int index) +{ + if (!dev->config->get_vq_affinity) + return NULL; + + return dev->config->get_vq_affinity(dev, index); +} +EXPORT_SYMBOL_GPL(virtio_get_vq_affinity); + +#ifdef CONFIG_BLK_MQ_VIRTIO +/** + * virtio_get_blk_mq_affinity - get affinity mask queue mapping for + * virtio device + * @dev_data: Pointer to struct virtio_device. + * @offset: Offset to use for the virtio irq vector + * @queue: Queue index + * + * This function returns for a queue the affinity mask for a virtio device. + * It is usually used as callback for blk_mq_hctx_map_queues(). + */ +const struct cpumask *virtio_get_blk_mq_affinity(void *dev_data, + int offset, int queue) +{ + struct virtio_device *vdev = dev_data; + + return virtio_get_vq_affinity(vdev, offset + queue); +} +EXPORT_SYMBOL_GPL(virtio_get_blk_mq_affinity); +#endif + static int virtio_init(void) { if (bus_register(&virtio_bus) != 0) diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 8d304b1d16b1..b9881a8794af 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -929,7 +929,12 @@ void blk_mq_freeze_queue_wait(struct request_queue *q); int blk_mq_freeze_queue_wait_timeout(struct request_queue *q, unsigned long timeout); +typedef const struct cpumask *(get_queue_affinty_fn)(void *dev_data, + int dev_off, int queue_idx); void blk_mq_map_queues(struct blk_mq_queue_map *qmap); +void blk_mq_hctx_map_queues(struct blk_mq_queue_map *qmap, + void *dev_data, int dev_off, + get_queue_affinty_fn *get_queue_affinity); 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/include/linux/pci.h b/include/linux/pci.h index 4cf89a4b4cbc..97f4797b5060 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1633,6 +1633,17 @@ resource_size_t pcibios_window_alignment(struct pci_bus *bus, int pci_set_vga_state(struct pci_dev *pdev, bool decode, unsigned int command_bits, u32 flags); +#ifdef CONFIG_BLK_MQ_PCI +const struct cpumask *pci_get_blk_mq_affinity(void *dev_data, + int offset, int queue); +#else +static inline const struct cpumask *pci_get_blk_mq_affinity(void *dev_data, + int offset, int queue) +{ + return cpu_possible_mask; +} +#endif + /* * Virtual interrupts allow for more interrupts to be allocated * than the device has interrupts for. These are not programmed diff --git a/include/linux/virtio.h b/include/linux/virtio.h index ecc5cb7b8c91..49d4f7353e5c 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -170,6 +170,19 @@ int virtio_device_restore(struct virtio_device *dev); void virtio_reset_device(struct virtio_device *dev); size_t virtio_max_dma_size(const struct virtio_device *vdev); +const struct cpumask *virtio_get_vq_affinity(struct virtio_device *dev, + int index); + +#ifdef CONFIG_BLK_MQ_VIRTIO +const struct cpumask *virtio_get_blk_mq_affinity(void *dev_data, + int offset, int queue); +#else +static inline const struct cpumask *virtio_get_blk_mq_affinity(void *dev_data, + int offset, int queue) +{ + return cpu_possible_mask; +} +#endif #define virtio_device_for_each_vq(vdev, vq) \ list_for_each_entry(vq, &vdev->vqs, list)