| Message ID | 20180323221923.24545-1-keith.busch@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Keith Thanks for your time and patch for this. On 03/24/2018 06:19 AM, Keith Busch wrote: > The PCI interrupt vectors intended to be associated with a queue may > not start at 0. This patch adds an offset parameter so blk-mq may find > the intended affinity mask. The default value is 0 so existing drivers > that don't care about this parameter don't need to change. > > Signed-off-by: Keith Busch <keith.busch@intel.com> > --- > block/blk-mq-pci.c | 12 ++++++++++-- > include/linux/blk-mq-pci.h | 2 ++ > 2 files changed, 12 insertions(+), 2 deletions(-) > > diff --git a/block/blk-mq-pci.c b/block/blk-mq-pci.c > index 76944e3271bf..1040a7705c13 100644 > --- a/block/blk-mq-pci.c > +++ b/block/blk-mq-pci.c > @@ -21,6 +21,7 @@ > * blk_mq_pci_map_queues - provide a default queue mapping for PCI device > * @set: tagset to provide the mapping for > * @pdev: PCI device associated with @set. > + * @offset: PCI irq starting vector offset > * > * This function assumes the PCI device @pdev has at least as many available > * interrupt vectors as @set has queues. It will then query the vector > @@ -28,13 +29,14 @@ > * that maps a queue to the CPUs that have irq affinity for the corresponding > * vector. > */ > -int blk_mq_pci_map_queues(struct blk_mq_tag_set *set, struct pci_dev *pdev) > +int __blk_mq_pci_map_queues(struct blk_mq_tag_set *set, struct pci_dev *pdev, > + int offset) > { > const struct cpumask *mask; > unsigned int queue, cpu; > > for (queue = 0; queue < set->nr_hw_queues; queue++) { > - mask = pci_irq_get_affinity(pdev, queue); > + mask = pci_irq_get_affinity(pdev, queue + offset); > if (!mask) > goto fallback; > Maybe we could provide a callback parameter for __blk_mq_pci_map_queues which give the mapping from hctx queue num to device-relative interrupt vector index. Thanks Jianchao
On Fri, Mar 23, 2018 at 04:19:21PM -0600, Keith Busch wrote: > The PCI interrupt vectors intended to be associated with a queue may > not start at 0. This patch adds an offset parameter so blk-mq may find > the intended affinity mask. The default value is 0 so existing drivers > that don't care about this parameter don't need to change. > > Signed-off-by: Keith Busch <keith.busch@intel.com> > --- > block/blk-mq-pci.c | 12 ++++++++++-- > include/linux/blk-mq-pci.h | 2 ++ > 2 files changed, 12 insertions(+), 2 deletions(-) > > diff --git a/block/blk-mq-pci.c b/block/blk-mq-pci.c > index 76944e3271bf..1040a7705c13 100644 > --- a/block/blk-mq-pci.c > +++ b/block/blk-mq-pci.c > @@ -21,6 +21,7 @@ > * blk_mq_pci_map_queues - provide a default queue mapping for PCI device > * @set: tagset to provide the mapping for > * @pdev: PCI device associated with @set. > + * @offset: PCI irq starting vector offset > * > * This function assumes the PCI device @pdev has at least as many available > * interrupt vectors as @set has queues. It will then query the vector > @@ -28,13 +29,14 @@ > * that maps a queue to the CPUs that have irq affinity for the corresponding > * vector. > */ > -int blk_mq_pci_map_queues(struct blk_mq_tag_set *set, struct pci_dev *pdev) > +int __blk_mq_pci_map_queues(struct blk_mq_tag_set *set, struct pci_dev *pdev, > + int offset) > { > const struct cpumask *mask; > unsigned int queue, cpu; > > for (queue = 0; queue < set->nr_hw_queues; queue++) { > - mask = pci_irq_get_affinity(pdev, queue); > + mask = pci_irq_get_affinity(pdev, queue + offset); > if (!mask) > goto fallback; > > @@ -50,4 +52,10 @@ int blk_mq_pci_map_queues(struct blk_mq_tag_set *set, struct pci_dev *pdev) > set->mq_map[cpu] = 0; > return 0; > } > +EXPORT_SYMBOL_GPL(__blk_mq_pci_map_queues); > + > +int blk_mq_pci_map_queues(struct blk_mq_tag_set *set, struct pci_dev *pdev) > +{ > + return __blk_mq_pci_map_queues(set, pdev, 0); > +} > EXPORT_SYMBOL_GPL(blk_mq_pci_map_queues); > diff --git a/include/linux/blk-mq-pci.h b/include/linux/blk-mq-pci.h > index 6338551e0fb9..5a92ecdbd78e 100644 > --- a/include/linux/blk-mq-pci.h > +++ b/include/linux/blk-mq-pci.h > @@ -5,6 +5,8 @@ > struct blk_mq_tag_set; > struct pci_dev; > > +int __blk_mq_pci_map_queues(struct blk_mq_tag_set *set, struct pci_dev *pdev, > + int offset); > int blk_mq_pci_map_queues(struct blk_mq_tag_set *set, struct pci_dev *pdev); > > #endif /* _LINUX_BLK_MQ_PCI_H */ > -- > 2.14.3 > Given no many callers of blk_mq_pci_map_queues(), I suggest to add the parameter of 'offset' to this API directly, then people may keep the '.pre_vectors' stuff in mind, and avoid to misuse it. Thanks, Ming
On Sat, Mar 24, 2018 at 09:55:49PM +0800, jianchao.wang wrote: > Maybe we could provide a callback parameter for __blk_mq_pci_map_queues which > give the mapping from hctx queue num to device-relative interrupt vector index. If a driver's mapping is so complicated as to require a special per-hctx callback, it'd be just as easy to implement the mapping in that driver's blk_mq_ops' 'map_queues' directly.
On Mon, Mar 26, 2018 at 09:50:38AM +0800, Ming Lei wrote: > > Given no many callers of blk_mq_pci_map_queues(), I suggest to add the > parameter of 'offset' to this API directly, then people may keep the > '.pre_vectors' stuff in mind, and avoid to misuse it. Yeah, I think I have to agree. I was trying really hard to not touch other drivers, but the concept doesn't seem odd enough to justify hiding it behind a default parameter. I'll send v2 tomorrow if there's no other feedback.
On Fri, Mar 23, 2018 at 04:19:21PM -0600, Keith Busch wrote: > The PCI interrupt vectors intended to be associated with a queue may > not start at 0. This patch adds an offset parameter so blk-mq may find > the intended affinity mask. The default value is 0 so existing drivers > that don't care about this parameter don't need to change. > > Signed-off-by: Keith Busch <keith.busch@intel.com> > --- > block/blk-mq-pci.c | 12 ++++++++++-- > include/linux/blk-mq-pci.h | 2 ++ > 2 files changed, 12 insertions(+), 2 deletions(-) > > diff --git a/block/blk-mq-pci.c b/block/blk-mq-pci.c > index 76944e3271bf..1040a7705c13 100644 > --- a/block/blk-mq-pci.c > +++ b/block/blk-mq-pci.c > @@ -21,6 +21,7 @@ > * blk_mq_pci_map_queues - provide a default queue mapping for PCI device > * @set: tagset to provide the mapping for > * @pdev: PCI device associated with @set. > + * @offset: PCI irq starting vector offset > * > * This function assumes the PCI device @pdev has at least as many available > * interrupt vectors as @set has queues. It will then query the vector > @@ -28,13 +29,14 @@ > * that maps a queue to the CPUs that have irq affinity for the corresponding > * vector. > */ > -int blk_mq_pci_map_queues(struct blk_mq_tag_set *set, struct pci_dev *pdev) > +int __blk_mq_pci_map_queues(struct blk_mq_tag_set *set, struct pci_dev *pdev, > + int offset) Can you just change the blk_mq_pci_map_queues prototype instead?
diff --git a/block/blk-mq-pci.c b/block/blk-mq-pci.c index 76944e3271bf..1040a7705c13 100644 --- a/block/blk-mq-pci.c +++ b/block/blk-mq-pci.c @@ -21,6 +21,7 @@ * blk_mq_pci_map_queues - provide a default queue mapping for PCI device * @set: tagset to provide the mapping for * @pdev: PCI device associated with @set. + * @offset: PCI irq starting vector offset * * This function assumes the PCI device @pdev has at least as many available * interrupt vectors as @set has queues. It will then query the vector @@ -28,13 +29,14 @@ * that maps a queue to the CPUs that have irq affinity for the corresponding * vector. */ -int blk_mq_pci_map_queues(struct blk_mq_tag_set *set, struct pci_dev *pdev) +int __blk_mq_pci_map_queues(struct blk_mq_tag_set *set, struct pci_dev *pdev, + int offset) { const struct cpumask *mask; unsigned int queue, cpu; for (queue = 0; queue < set->nr_hw_queues; queue++) { - mask = pci_irq_get_affinity(pdev, queue); + mask = pci_irq_get_affinity(pdev, queue + offset); if (!mask) goto fallback; @@ -50,4 +52,10 @@ int blk_mq_pci_map_queues(struct blk_mq_tag_set *set, struct pci_dev *pdev) set->mq_map[cpu] = 0; return 0; } +EXPORT_SYMBOL_GPL(__blk_mq_pci_map_queues); + +int blk_mq_pci_map_queues(struct blk_mq_tag_set *set, struct pci_dev *pdev) +{ + return __blk_mq_pci_map_queues(set, pdev, 0); +} EXPORT_SYMBOL_GPL(blk_mq_pci_map_queues); diff --git a/include/linux/blk-mq-pci.h b/include/linux/blk-mq-pci.h index 6338551e0fb9..5a92ecdbd78e 100644 --- a/include/linux/blk-mq-pci.h +++ b/include/linux/blk-mq-pci.h @@ -5,6 +5,8 @@ struct blk_mq_tag_set; struct pci_dev; +int __blk_mq_pci_map_queues(struct blk_mq_tag_set *set, struct pci_dev *pdev, + int offset); int blk_mq_pci_map_queues(struct blk_mq_tag_set *set, struct pci_dev *pdev); #endif /* _LINUX_BLK_MQ_PCI_H */
The PCI interrupt vectors intended to be associated with a queue may not start at 0. This patch adds an offset parameter so blk-mq may find the intended affinity mask. The default value is 0 so existing drivers that don't care about this parameter don't need to change. Signed-off-by: Keith Busch <keith.busch@intel.com> --- block/blk-mq-pci.c | 12 ++++++++++-- include/linux/blk-mq-pci.h | 2 ++ 2 files changed, 12 insertions(+), 2 deletions(-)