From 06ee6d571f0e350253a8fc3492316b2be007fae2 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Mon, 4 Jul 2016 17:39:24 +0900 Subject: genirq: Add affinity hint to irq allocation Add an extra argument to the irq(domain) allocation functions, so we can hand down affinity hints to the allocator. Thats necessary to implement proper support for multiqueue devices. Signed-off-by: Thomas Gleixner Cc: Christoph Hellwig 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/1467621574-8277-4-git-send-email-hch@lst.de Signed-off-by: Thomas Gleixner --- kernel/irq/irqdesc.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) (limited to 'kernel/irq/irqdesc.c') diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c index 8731e1c5d1e7..b8df4fcdbb5f 100644 --- a/kernel/irq/irqdesc.c +++ b/kernel/irq/irqdesc.c @@ -223,7 +223,7 @@ static void free_desc(unsigned int irq) } static int alloc_descs(unsigned int start, unsigned int cnt, int node, - struct module *owner) + const struct cpumask *affinity, struct module *owner) { struct irq_desc *desc; int i; @@ -333,6 +333,7 @@ static void free_desc(unsigned int irq) } static inline int alloc_descs(unsigned int start, unsigned int cnt, int node, + const struct cpumask *affinity, struct module *owner) { u32 i; @@ -453,12 +454,15 @@ EXPORT_SYMBOL_GPL(irq_free_descs); * @cnt: Number of consecutive irqs to allocate. * @node: Preferred node on which the irq descriptor should be allocated * @owner: Owning module (can be NULL) + * @affinity: Optional pointer to an affinity mask which hints where the + * irq descriptors should be allocated and which default + * affinities to use * * Returns the first irq number or error code */ int __ref __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node, - struct module *owner) + struct module *owner, const struct cpumask *affinity) { int start, ret; @@ -494,7 +498,7 @@ __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node, bitmap_set(allocated_irqs, start, cnt); mutex_unlock(&sparse_irq_lock); - return alloc_descs(start, cnt, node, owner); + return alloc_descs(start, cnt, node, affinity, owner); err: mutex_unlock(&sparse_irq_lock); @@ -512,7 +516,7 @@ EXPORT_SYMBOL_GPL(__irq_alloc_descs); */ unsigned int irq_alloc_hwirqs(int cnt, int node) { - int i, irq = __irq_alloc_descs(-1, 0, cnt, node, NULL); + int i, irq = __irq_alloc_descs(-1, 0, cnt, node, NULL, NULL); if (irq < 0) return 0; -- cgit v1.2.3-70-g09d2 From 45ddcecbfa947f1dd8e8019bad9e90d6c9f2665c Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Mon, 4 Jul 2016 17:39:25 +0900 Subject: genirq: Use affinity hint in irqdesc allocation Use the affinity hint in the irqdesc allocator. The hint is used to determine the node for the allocation and to set the affinity of the interrupt. If multiple interrupts are allocated (multi-MSI) then the allocator iterates over the cpumask and for each set cpu it allocates on their node and sets the initial affinity to that cpu. If a single interrupt is allocated (MSI-X) then the allocator uses the first cpu in the mask to compute the allocation node and uses the mask for the initial affinity setting. Interrupts set up this way are marked with the AFFINITY_MANAGED flag to prevent userspace from messing with their affinity settings. Signed-off-by: Thomas Gleixner Cc: Christoph Hellwig 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/1467621574-8277-5-git-send-email-hch@lst.de Signed-off-by: Thomas Gleixner --- kernel/irq/irqdesc.c | 51 +++++++++++++++++++++++++++++++++++++++------------ 1 file changed, 39 insertions(+), 12 deletions(-) (limited to 'kernel/irq/irqdesc.c') diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c index b8df4fcdbb5f..a623b44f2d4b 100644 --- a/kernel/irq/irqdesc.c +++ b/kernel/irq/irqdesc.c @@ -68,9 +68,13 @@ static int alloc_masks(struct irq_desc *desc, gfp_t gfp, int node) return 0; } -static void desc_smp_init(struct irq_desc *desc, int node) +static void desc_smp_init(struct irq_desc *desc, int node, + const struct cpumask *affinity) { - cpumask_copy(desc->irq_common_data.affinity, irq_default_affinity); + if (!affinity) + affinity = irq_default_affinity; + cpumask_copy(desc->irq_common_data.affinity, affinity); + #ifdef CONFIG_GENERIC_PENDING_IRQ cpumask_clear(desc->pending_mask); #endif @@ -82,11 +86,12 @@ static void desc_smp_init(struct irq_desc *desc, int node) #else static inline int alloc_masks(struct irq_desc *desc, gfp_t gfp, int node) { return 0; } -static inline void desc_smp_init(struct irq_desc *desc, int node) { } +static inline void +desc_smp_init(struct irq_desc *desc, int node, const struct cpumask *affinity) { } #endif static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node, - struct module *owner) + const struct cpumask *affinity, struct module *owner) { int cpu; @@ -107,7 +112,7 @@ static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node, desc->owner = owner; for_each_possible_cpu(cpu) *per_cpu_ptr(desc->kstat_irqs, cpu) = 0; - desc_smp_init(desc, node); + desc_smp_init(desc, node, affinity); } int nr_irqs = NR_IRQS; @@ -158,7 +163,9 @@ void irq_unlock_sparse(void) mutex_unlock(&sparse_irq_lock); } -static struct irq_desc *alloc_desc(int irq, int node, struct module *owner) +static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags, + const struct cpumask *affinity, + struct module *owner) { struct irq_desc *desc; gfp_t gfp = GFP_KERNEL; @@ -178,7 +185,8 @@ static struct irq_desc *alloc_desc(int irq, int node, struct module *owner) lockdep_set_class(&desc->lock, &irq_desc_lock_class); init_rcu_head(&desc->rcu); - desc_set_defaults(irq, desc, node, owner); + desc_set_defaults(irq, desc, node, affinity, owner); + irqd_set(&desc->irq_data, flags); return desc; @@ -225,11 +233,30 @@ static void free_desc(unsigned int irq) static int alloc_descs(unsigned int start, unsigned int cnt, int node, const struct cpumask *affinity, struct module *owner) { + const struct cpumask *mask = NULL; struct irq_desc *desc; - int i; + unsigned int flags; + int i, cpu = -1; + + if (affinity && cpumask_empty(affinity)) + return -EINVAL; + + flags = affinity ? IRQD_AFFINITY_MANAGED : 0; for (i = 0; i < cnt; i++) { - desc = alloc_desc(start + i, node, owner); + if (affinity) { + cpu = cpumask_next(cpu, affinity); + if (cpu >= nr_cpu_ids) + cpu = cpumask_first(affinity); + node = cpu_to_node(cpu); + + /* + * For single allocations we use the caller provided + * mask otherwise we use the mask of the target cpu + */ + mask = cnt == 1 ? affinity : cpumask_of(cpu); + } + desc = alloc_desc(start + i, node, flags, mask, owner); if (!desc) goto err; mutex_lock(&sparse_irq_lock); @@ -277,7 +304,7 @@ int __init early_irq_init(void) nr_irqs = initcnt; for (i = 0; i < initcnt; i++) { - desc = alloc_desc(i, node, NULL); + desc = alloc_desc(i, node, 0, NULL, NULL); set_bit(i, allocated_irqs); irq_insert_desc(i, desc); } @@ -311,7 +338,7 @@ int __init early_irq_init(void) alloc_masks(&desc[i], GFP_KERNEL, node); raw_spin_lock_init(&desc[i].lock); lockdep_set_class(&desc[i].lock, &irq_desc_lock_class); - desc_set_defaults(i, &desc[i], node, NULL); + desc_set_defaults(i, &desc[i], node, NULL, NULL); } return arch_early_irq_init(); } @@ -328,7 +355,7 @@ static void free_desc(unsigned int irq) unsigned long flags; raw_spin_lock_irqsave(&desc->lock, flags); - desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL); + desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL); raw_spin_unlock_irqrestore(&desc->lock, flags); } -- cgit v1.2.3-70-g09d2