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 <[email protected]> --- include/linux/irq.h | 5 ++ kernel/irq/ipi.c | 192 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 197 insertions(+) diff --git a/include/linux/irq.h b/include/linux/irq.h index ee01e89c2140..eee522a04a7c 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -1081,4 +1081,9 @@ 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_coproc_single(unsigned int virq, unsigned int cpu); +int ipi_send_coproc_mask(unsigned int virq, const struct ipi_mask *dest); + #endif /* _LINUX_IRQ_H */ diff --git a/kernel/irq/ipi.c b/kernel/irq/ipi.c index d6faa0e768b8..e07642d0e59a 100644 --- a/kernel/irq/ipi.c +++ b/kernel/irq/ipi.c @@ -284,3 +284,195 @@ 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 = desc ? irq_desc_get_irq_data(desc) : NULL; + struct irq_chip *chip = data ? irq_data_get_irq_chip(data) : NULL; + struct ipi_mask *ipimask = data ? irq_data_get_ipi_mask(data) : NULL; + const struct cpumask *dest = cpumask_of(cpu); + + /* do we want to make the checks below optional to reduce the overhead + * since the only user of this function is arch code? */ + if (!chip || !ipimask) + return -EINVAL; + + if (!chip->ipi_send_single && !chip->ipi_send_mask) + return -EINVAL; + + if (!ipimask->global || cpu > nr_cpu_ids) + return -EINVAL; + + if (!cpumask_subset(dest, &ipimask->cpumask)) + return -EINVAL; + + 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 = desc ? irq_desc_get_irq_data(desc) : NULL; + struct irq_chip *chip = data ? irq_data_get_irq_chip(data) : NULL; + struct ipi_mask *ipimask = data ? irq_data_get_ipi_mask(data) : NULL; + unsigned int cpu; + + /* do we want to make the checks below optional to reduce the overhead + * since the only user of this function is arch code? */ + if (!chip || !ipimask) + return -EINVAL; + + if (!chip->ipi_send_single && !chip->ipi_send_mask) + return -EINVAL; + + if (!ipimask->global) + return -EINVAL; + + if (!cpumask_subset(dest, &ipimask->cpumask)) + return -EINVAL; + + 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 - ipimask->offset); + chip->ipi_send_single(data, cpu); + } + } else { + for_each_cpu(cpu, dest) + chip->ipi_send_single(data, cpu); + } + + return 0; +} + +/** + * ipi_send_coproc_single - send an IPI to a single coprocessor + * @virq: linux irq number from irq_reserve_ipi() + * @cpu: cpu value of coprocessor. + * Must be a subset of the mask passed to irq_reserve_ipi() + * + * Sends an IPI to single coprcessor + * + * Returns zero on success and negative error number on failure. + */ +int ipi_send_coproc_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 ipi_mask *ipimask = data ? irq_data_get_ipi_mask(data) : NULL; + + if (!chip || !ipimask) + return -EINVAL; + + if (!chip->ipi_send_coproc_single && !chip->ipi_send_coproc_mask) + return -EINVAL; + + if (cpu > ipimask->nbits) + return -EINVAL; + + if (ipimask->global) + return -EINVAL; + + if (!test_bit(cpu, ipimask->cpu_bitmap)) + return -EINVAL; + + if (chip->ipi_send_single) { + chip->ipi_send_coproc_single(data, cpu); + } else { + struct ipi_mask *dest = ipi_mask_alloc(cpu); + if (!dest) + return -ENOMEM; + set_bit(cpu, dest->cpu_bitmap); + chip->ipi_send_coproc_mask(data, dest); + ipi_mask_free(dest); + } + + return 0; +} +EXPORT_SYMBOL_GPL(ipi_send_coproc_single); + +/** + * ipi_send_coproc_mask - send an IPI to target coprocessor(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 coprcessors in dest mask. + * + * Returns zero on success and negative error number on failure. + */ +int ipi_send_coproc_mask(unsigned int virq, const struct ipi_mask *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 ipi_mask *ipimask = data ? irq_data_get_ipi_mask(data) : NULL; + unsigned int cpu; + + if (!chip || !ipimask) + return -EINVAL; + + if (!chip->ipi_send_coproc_single && !chip->ipi_send_coproc_mask) + return -EINVAL; + + if (dest->nbits > ipimask->nbits) + return -EINVAL; + + if (ipimask->global || dest->global) + return -EINVAL; + + if (!bitmap_subset(dest->cpu_bitmap, + ipimask->cpu_bitmap, + dest->nbits)) + return -EINVAL; + + if (chip->ipi_send_mask) { + chip->ipi_send_coproc_mask(data, dest); + return 0; + } + + if (irq_domain_is_ipi_per_cpu(data->domain)) { + unsigned int base_virq = data->irq; + ipi_mask_for_each_cpu(cpu, dest) { + data = irq_get_irq_data(base_virq + cpu - ipimask->offset); + chip->ipi_send_coproc_single(data, cpu); + } + } else { + ipi_mask_for_each_cpu(cpu, dest) + chip->ipi_send_coproc_single(data, cpu); + } + + return 0; +} +EXPORT_SYMBOL_GPL(ipi_send_coproc_mask); -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
