Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1281722

[PATCH v3 11/19] genirq: Implement ipi_send_{mask, single}()

Show all headers | View raw

Add APIs to send single or mask IPI. We have 2 variants, one that uses cpumask
and to be used by arch code to send regular SMP IPIs. And another that uses
ipi_mask to be used by drivers to send IPIs to coprocessors.

Signed-off-by: Qais Yousef <qais.yousef@imgtec.com>
---
 include/linux/irq.h |   5 ++
 kernel/irq/ipi.c    | 165 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 170 insertions(+)

diff --git a/include/linux/irq.h b/include/linux/irq.h
index b0556c5787d7..f521f1ac36d4 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -988,4 +988,9 @@ irq_hw_number_t irq_ipi_mapping_get_hwirq(struct ipi_mapping *map,
 
 irq_hw_number_t ipi_get_hwirq(unsigned int irq, unsigned int cpu);
 
+int __ipi_send_single(struct irq_desc *desc, unsigned int cpu);
+int __ipi_send_mask(struct irq_desc *desc, const struct cpumask *dest);
+int ipi_send_single(unsigned int virq, unsigned int cpu);
+int ipi_send_mask(unsigned int virq, const struct cpumask *dest);
+
 #endif /* _LINUX_IRQ_H */
diff --git a/kernel/irq/ipi.c b/kernel/irq/ipi.c
index 814162b72aed..02882ca8f336 100644
--- a/kernel/irq/ipi.c
+++ b/kernel/irq/ipi.c
@@ -270,3 +270,168 @@ irq_hw_number_t ipi_get_hwirq(unsigned int irq, unsigned int cpu)
 	return hwirq;
 }
 EXPORT_SYMBOL_GPL(ipi_get_hwirq);
+
+/**
+ * __ipi_send_single - send an IPI to a target Linux SMP CPU
+ * @desc: pointer to irq_desc of the IRQ
+ * @cpu: dest CPU, must be the same or a subset of the mask passed to
+ *        irq_reserve_ipi()
+ *
+ * Sends an IPI to a single smp cpu
+ * This function is meant to be used from arch code to send single SMP IPI.
+ *
+ * Returns zero on success and negative error number on failure.
+ */
+int __ipi_send_single(struct irq_desc *desc, unsigned int cpu)
+{
+	struct irq_data *data = irq_desc_get_irq_data(desc);
+	struct irq_chip *chip = irq_data_get_irq_chip(data);
+	const struct cpumask *dest = cpumask_of(cpu);
+
+#ifdef DEBUG
+	/*
+	 * Minimise the overhead by omitting the checks for Linux SMP IPIs.
+	 * Since the callers should be ARCH code which is generally trusted,
+	 * only check for errors when debugging.
+	 */
+	struct cpumask *ipimask = data ? irq_data_get_affinity_mask(data) : NULL;
+
+	if (!chip || !ipimask)
+		return -EINVAL;
+
+	if (!chip->ipi_send_single && !chip->ipi_send_mask)
+		return -EINVAL;
+
+	if (cpu > nr_cpu_ids)
+		return -EINVAL;
+
+	if (!cpumask_test_cpu(cpu, ipimask))
+		return -EINVAL;
+#endif
+
+	if (chip->ipi_send_single)
+		chip->ipi_send_single(data, cpu);
+	else
+		chip->ipi_send_mask(data, dest);
+	return 0;
+}
+
+/**
+ * ipi_send_mask - send an IPI to target Linux SMP CPU(s)
+ * @desc: pointer to irq_desc of the IRQ
+ * @dest: dest CPU(s), must be the same or a subset of the mask passed to
+ *        irq_reserve_ipi()
+ *
+ * Sends an IPI to all smp cpus in dest mask.
+ * This function is meant to be used from arch code to send SMP IPIs.
+ *
+ * Returns zero on success and negative error number on failure.
+ */
+int __ipi_send_mask(struct irq_desc *desc, const struct cpumask *dest)
+{
+	struct irq_data *data = irq_desc_get_irq_data(desc);
+	struct irq_chip *chip = irq_data_get_irq_chip(data);
+	unsigned int cpu;
+
+#ifdef DEBUG
+	/*
+	 * Minimise the overhead by omitting the checks for Linux SMP IPIs.
+	 * Since the callers should be ARCH code which is generally trusted,
+	 * only check for errors when debugging.
+	 */
+	struct cpumask *ipimask = data ? irq_data_get_affinity_mask(data) : NULL;
+
+	if (!chip || !ipimask)
+		return -EINVAL;
+
+	if (!chip->ipi_send_single && !chip->ipi_send_mask)
+		return -EINVAL;
+
+	if (!cpumask_subset(dest, ipimask))
+		return -EINVAL;
+#endif
+
+	if (chip->ipi_send_mask) {
+		chip->ipi_send_mask(data, dest);
+		return 0;
+	}
+
+	if (irq_domain_is_ipi_per_cpu(data->domain)) {
+		unsigned int base_virq = data->irq;
+		for_each_cpu(cpu, dest) {
+			data = irq_get_irq_data(base_virq + cpu - data->common->ipi_offset);
+			chip->ipi_send_single(data, cpu);
+		}
+	} else {
+		for_each_cpu(cpu, dest)
+			chip->ipi_send_single(data, cpu);
+	}
+
+	return 0;
+}
+
+/**
+ * ipi_send_single - send an IPI to a single CPU
+ * @virq: linux irq number from irq_reserve_ipi()
+ * @cpu: CPU ID. Must be a subset of the mask passed to irq_reserve_ipi()
+ *
+ * Sends an IPI to destination CPU
+ *
+ * Returns zero on success and negative error number on failure.
+ */
+int ipi_send_single(unsigned int virq, unsigned int cpu)
+{
+	struct irq_desc *desc = irq_to_desc(virq);
+	struct irq_data *data = desc ? irq_desc_get_irq_data(desc) : NULL;
+	struct irq_chip *chip = data ? irq_data_get_irq_chip(data) : NULL;
+	struct cpumask *ipimask = data ? irq_data_get_affinity_mask(data) : NULL;
+
+	if (!chip || !ipimask)
+		return -EINVAL;
+
+	if (!chip->ipi_send_single && !chip->ipi_send_mask)
+		return -EINVAL;
+
+	if (cpu > nr_cpu_ids)
+		return -EINVAL;
+
+	if (!cpumask_test_cpu(cpu, ipimask))
+		return -EINVAL;
+
+	__ipi_send_single(desc, cpu);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(ipi_send_single);
+
+/**
+ * ipi_send_mask - send an IPI to target CPU(s)
+ * @virq: linux irq number from irq_reserve_ipi()
+ * @dest: dest CPU(s), must be the same or a subset of the mask passed to
+ *        irq_reserve_ipi()
+ *
+ * Sends an IPI to all prcessors in dest mask.
+ *
+ * Returns zero on success and negative error number on failure.
+ */
+int ipi_send_mask(unsigned int virq, const struct cpumask *dest)
+{
+	struct irq_desc *desc = irq_to_desc(virq);
+	struct irq_data *data = desc ? irq_desc_get_irq_data(desc) : NULL;
+	struct irq_chip *chip = data ? irq_data_get_irq_chip(data) : NULL;
+	struct cpumask *ipimask = data ? irq_data_get_affinity_mask(data) : NULL;
+
+	if (!chip || !ipimask)
+		return -EINVAL;
+
+	if (!chip->ipi_send_single && !chip->ipi_send_mask)
+		return -EINVAL;
+
+	if (!cpumask_subset(dest, ipimask))
+		return -EINVAL;
+
+	__ipi_send_mask(desc, dest);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(ipi_send_mask);
-- 
2.1.0

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH v3 00/19] Implement generic IPI support mechanism Qais Yousef <qais.yousef@imgtec.com> - 2015-12-02 13:30 +0100
  [PATCH v3 01/19] genirq: Add new IRQ_DOMAIN_FLAGS_IPI Qais Yousef <qais.yousef@imgtec.com> - 2015-12-02 13:30 +0100
  [PATCH v3 04/19] genirq: Add struct ipi_mapping and its helper functions Qais Yousef <qais.yousef@imgtec.com> - 2015-12-02 13:30 +0100
  [PATCH v3 08/19] genirq: Add a new generic IPI reservation code to irq core Qais Yousef <qais.yousef@imgtec.com> - 2015-12-02 13:30 +0100
  [PATCH v3 11/19] genirq: Implement ipi_send_{mask, single}() Qais Yousef <qais.yousef@imgtec.com> - 2015-12-02 13:30 +0100
  [PATCH v3 09/19] genirq: Add a new function to get IPI reverse mapping Qais Yousef <qais.yousef@imgtec.com> - 2015-12-02 13:30 +0100
  [PATCH v3 17/19] MIPS: Make smp CMP, CPS and MT use the new generic IPI functions Qais Yousef <qais.yousef@imgtec.com> - 2015-12-02 13:30 +0100
  [PATCH v3 18/19] MIPS: Delete smp-gic.c Qais Yousef <qais.yousef@imgtec.com> - 2015-12-02 13:30 +0100
  [PATCH v3 03/19] genirq: Add GENERIC_IRQ_IPI Kconfig symbol Qais Yousef <qais.yousef@imgtec.com> - 2015-12-02 13:30 +0100
  [PATCH v3 02/19] genirq: Add DOMAIN_BUS_IPI Qais Yousef <qais.yousef@imgtec.com> - 2015-12-02 13:30 +0100
  [PATCH v3 05/19] genirq: Add ipi_offset to irq_common_data Qais Yousef <qais.yousef@imgtec.com> - 2015-12-02 13:30 +0100
  [PATCH v3 13/19] irqchip/mips-gic: Add device hierarchy domain Qais Yousef <qais.yousef@imgtec.com> - 2015-12-02 13:30 +0100
  [PATCH v3 19/19] irqchip/mips-gic: Add new DT property to reserve IPIs Qais Yousef <qais.yousef@imgtec.com> - 2015-12-02 13:30 +0100
  [PATCH v3 07/19] genirq: Make irq_domain_alloc_descs() non static Qais Yousef <qais.yousef@imgtec.com> - 2015-12-02 13:30 +0100
  [PATCH v3 10/19] genirq: Add a new irq_send_ipi() to irq_chip Qais Yousef <qais.yousef@imgtec.com> - 2015-12-02 13:30 +0100
  [PATCH v3 16/19] MIPS: Add generic SMP IPI support Qais Yousef <qais.yousef@imgtec.com> - 2015-12-02 13:30 +0100
  [PATCH v3 06/19] genirq: Add an extra comment about the use of affinity in irq_common_data Qais Yousef <qais.yousef@imgtec.com> - 2015-12-02 13:30 +0100
  [PATCH v3 12/19] irqchip/mips-gic: Add a IPI hierarchy domain Qais Yousef <qais.yousef@imgtec.com> - 2015-12-02 13:30 +0100

csiph-web