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-rw-r--r--kernel/irq/Makefile1
-rw-r--r--kernel/irq/affinity.c61
-rw-r--r--kernel/irq/internals.h2
-rw-r--r--kernel/irq/ipi.c2
-rw-r--r--kernel/irq/irqdesc.c63
-rw-r--r--kernel/irq/irqdomain.c22
-rw-r--r--kernel/irq/manage.c28
-rw-r--r--kernel/irq/msi.c11
-rw-r--r--kernel/irq/proc.c2
9 files changed, 153 insertions, 39 deletions
diff --git a/kernel/irq/Makefile b/kernel/irq/Makefile
index 2ee42e95a3ce..1d3ee3169202 100644
--- a/kernel/irq/Makefile
+++ b/kernel/irq/Makefile
@@ -9,3 +9,4 @@ obj-$(CONFIG_GENERIC_IRQ_MIGRATION) += cpuhotplug.o
obj-$(CONFIG_PM_SLEEP) += pm.o
obj-$(CONFIG_GENERIC_MSI_IRQ) += msi.o
obj-$(CONFIG_GENERIC_IRQ_IPI) += ipi.o
+obj-$(CONFIG_SMP) += affinity.o
diff --git a/kernel/irq/affinity.c b/kernel/irq/affinity.c
new file mode 100644
index 000000000000..f68959341c0f
--- /dev/null
+++ b/kernel/irq/affinity.c
@@ -0,0 +1,61 @@
+
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/cpu.h>
+
+static int get_first_sibling(unsigned int cpu)
+{
+ unsigned int ret;
+
+ ret = cpumask_first(topology_sibling_cpumask(cpu));
+ if (ret < nr_cpu_ids)
+ return ret;
+ return cpu;
+}
+
+/*
+ * Take a map of online CPUs and the number of available interrupt vectors
+ * and generate an output cpumask suitable for spreading MSI/MSI-X vectors
+ * so that they are distributed as good as possible around the CPUs. If
+ * more vectors than CPUs are available we'll map one to each CPU,
+ * otherwise we map one to the first sibling of each socket.
+ *
+ * If there are more vectors than CPUs we will still only have one bit
+ * set per CPU, but interrupt code will keep on assigning the vectors from
+ * the start of the bitmap until we run out of vectors.
+ */
+struct cpumask *irq_create_affinity_mask(unsigned int *nr_vecs)
+{
+ struct cpumask *affinity_mask;
+ unsigned int max_vecs = *nr_vecs;
+
+ if (max_vecs == 1)
+ return NULL;
+
+ affinity_mask = kzalloc(cpumask_size(), GFP_KERNEL);
+ if (!affinity_mask) {
+ *nr_vecs = 1;
+ return NULL;
+ }
+
+ if (max_vecs >= num_online_cpus()) {
+ cpumask_copy(affinity_mask, cpu_online_mask);
+ *nr_vecs = num_online_cpus();
+ } else {
+ unsigned int vecs = 0, cpu;
+
+ for_each_online_cpu(cpu) {
+ if (cpu == get_first_sibling(cpu)) {
+ cpumask_set_cpu(cpu, affinity_mask);
+ vecs++;
+ }
+
+ if (--max_vecs == 0)
+ break;
+ }
+ *nr_vecs = vecs;
+ }
+
+ return affinity_mask;
+}
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index 0c6f35ba9cc0..bc226e783bd2 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -107,6 +107,8 @@ static inline void unregister_handler_proc(unsigned int irq,
struct irqaction *action) { }
#endif
+extern bool irq_can_set_affinity_usr(unsigned int irq);
+
extern int irq_select_affinity_usr(unsigned int irq, struct cpumask *mask);
extern void irq_set_thread_affinity(struct irq_desc *desc);
diff --git a/kernel/irq/ipi.c b/kernel/irq/ipi.c
index 89b49f6773f0..4fd23510d5f2 100644
--- a/kernel/irq/ipi.c
+++ b/kernel/irq/ipi.c
@@ -76,7 +76,7 @@ int irq_reserve_ipi(struct irq_domain *domain,
}
}
- virq = irq_domain_alloc_descs(-1, nr_irqs, 0, NUMA_NO_NODE);
+ virq = irq_domain_alloc_descs(-1, nr_irqs, 0, NUMA_NO_NODE, NULL);
if (virq <= 0) {
pr_warn("Can't reserve IPI, failed to alloc descs\n");
return -ENOMEM;
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 8731e1c5d1e7..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;
@@ -223,13 +231,32 @@ 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)
{
+ 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();
}
@@ -328,11 +355,12 @@ 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);
}
static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
+ const struct cpumask *affinity,
struct module *owner)
{
u32 i;
@@ -453,12 +481,15 @@ 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 +525,7 @@ __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 +543,7 @@ 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;
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 5d89d724a02a..a82853739694 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -481,7 +481,7 @@ unsigned int irq_create_mapping(struct irq_domain *domain,
}
/* Allocate a virtual interrupt number */
- virq = irq_domain_alloc_descs(-1, 1, hwirq, of_node_to_nid(of_node));
+ virq = irq_domain_alloc_descs(-1, 1, hwirq, of_node_to_nid(of_node), NULL);
if (virq <= 0) {
pr_debug("-> virq allocation failed\n");
return 0;
@@ -879,19 +879,23 @@ const struct irq_domain_ops irq_domain_simple_ops = {
EXPORT_SYMBOL_GPL(irq_domain_simple_ops);
int irq_domain_alloc_descs(int virq, unsigned int cnt, irq_hw_number_t hwirq,
- int node)
+ int node, const struct cpumask *affinity)
{
unsigned int hint;
if (virq >= 0) {
- virq = irq_alloc_descs(virq, virq, cnt, node);
+ virq = __irq_alloc_descs(virq, virq, cnt, node, THIS_MODULE,
+ affinity);
} else {
hint = hwirq % nr_irqs;
if (hint == 0)
hint++;
- virq = irq_alloc_descs_from(hint, cnt, node);
- if (virq <= 0 && hint > 1)
- virq = irq_alloc_descs_from(1, cnt, node);
+ virq = __irq_alloc_descs(-1, hint, cnt, node, THIS_MODULE,
+ affinity);
+ if (virq <= 0 && hint > 1) {
+ virq = __irq_alloc_descs(-1, 1, cnt, node, THIS_MODULE,
+ affinity);
+ }
}
return virq;
@@ -1204,6 +1208,7 @@ int irq_domain_alloc_irqs_recursive(struct irq_domain *domain,
* @node: NUMA node id for memory allocation
* @arg: domain specific argument
* @realloc: IRQ descriptors have already been allocated if true
+ * @affinity: Optional irq affinity mask for multiqueue devices
*
* Allocate IRQ numbers and initialized all data structures to support
* hierarchy IRQ domains.
@@ -1219,7 +1224,7 @@ int irq_domain_alloc_irqs_recursive(struct irq_domain *domain,
*/
int __irq_domain_alloc_irqs(struct irq_domain *domain, int irq_base,
unsigned int nr_irqs, int node, void *arg,
- bool realloc)
+ bool realloc, const struct cpumask *affinity)
{
int i, ret, virq;
@@ -1237,7 +1242,8 @@ int __irq_domain_alloc_irqs(struct irq_domain *domain, int irq_base,
if (realloc && irq_base >= 0) {
virq = irq_base;
} else {
- virq = irq_domain_alloc_descs(irq_base, nr_irqs, 0, node);
+ virq = irq_domain_alloc_descs(irq_base, nr_irqs, 0, node,
+ affinity);
if (virq < 0) {
pr_debug("cannot allocate IRQ(base %d, count %d)\n",
irq_base, nr_irqs);
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 00cfc852cca8..73a2b786b5e9 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -115,12 +115,12 @@ EXPORT_SYMBOL(synchronize_irq);
#ifdef CONFIG_SMP
cpumask_var_t irq_default_affinity;
-static int __irq_can_set_affinity(struct irq_desc *desc)
+static bool __irq_can_set_affinity(struct irq_desc *desc)
{
if (!desc || !irqd_can_balance(&desc->irq_data) ||
!desc->irq_data.chip || !desc->irq_data.chip->irq_set_affinity)
- return 0;
- return 1;
+ return false;
+ return true;
}
/**
@@ -134,6 +134,21 @@ int irq_can_set_affinity(unsigned int irq)
}
/**
+ * irq_can_set_affinity_usr - Check if affinity of a irq can be set from user space
+ * @irq: Interrupt to check
+ *
+ * Like irq_can_set_affinity() above, but additionally checks for the
+ * AFFINITY_MANAGED flag.
+ */
+bool irq_can_set_affinity_usr(unsigned int irq)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ return __irq_can_set_affinity(desc) &&
+ !irqd_affinity_is_managed(&desc->irq_data);
+}
+
+/**
* irq_set_thread_affinity - Notify irq threads to adjust affinity
* @desc: irq descriptor which has affitnity changed
*
@@ -338,10 +353,11 @@ static int setup_affinity(struct irq_desc *desc, struct cpumask *mask)
return 0;
/*
- * Preserve an userspace affinity setup, but make sure that
- * one of the targets is online.
+ * Preserve the managed affinity setting and an userspace affinity
+ * setup, but make sure that one of the targets is online.
*/
- if (irqd_has_set(&desc->irq_data, IRQD_AFFINITY_SET)) {
+ if (irqd_affinity_is_managed(&desc->irq_data) ||
+ irqd_has_set(&desc->irq_data, IRQD_AFFINITY_SET)) {
if (cpumask_intersects(desc->irq_common_data.affinity,
cpu_online_mask))
set = desc->irq_common_data.affinity;
diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c
index 38e89ce7b071..0e2a736b14a7 100644
--- a/kernel/irq/msi.c
+++ b/kernel/irq/msi.c
@@ -324,7 +324,7 @@ int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,
struct msi_domain_ops *ops = info->ops;
msi_alloc_info_t arg;
struct msi_desc *desc;
- int i, ret, virq = -1;
+ int i, ret, virq;
ret = msi_domain_prepare_irqs(domain, dev, nvec, &arg);
if (ret)
@@ -332,13 +332,10 @@ int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,
for_each_msi_entry(desc, dev) {
ops->set_desc(&arg, desc);
- if (info->flags & MSI_FLAG_IDENTITY_MAP)
- virq = (int)ops->get_hwirq(info, &arg);
- else
- virq = -1;
- virq = __irq_domain_alloc_irqs(domain, virq, desc->nvec_used,
- dev_to_node(dev), &arg, false);
+ virq = __irq_domain_alloc_irqs(domain, -1, desc->nvec_used,
+ dev_to_node(dev), &arg, false,
+ desc->affinity);
if (virq < 0) {
ret = -ENOSPC;
if (ops->handle_error)
diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c
index f30425dce9dd..feaa813b84a9 100644
--- a/kernel/irq/proc.c
+++ b/kernel/irq/proc.c
@@ -96,7 +96,7 @@ static ssize_t write_irq_affinity(int type, struct file *file,
cpumask_var_t new_value;
int err;
- if (!irq_can_set_affinity(irq) || no_irq_affinity)
+ if (!irq_can_set_affinity_usr(irq) || no_irq_affinity)
return -EIO;
if (!alloc_cpumask_var(&new_value, GFP_KERNEL))