From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753905AbbKCLNp (ORCPT ); Tue, 3 Nov 2015 06:13:45 -0500 Received: from mailapp01.imgtec.com ([195.59.15.196]:37469 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753575AbbKCLNj (ORCPT ); Tue, 3 Nov 2015 06:13:39 -0500 From: Qais Yousef To: CC: , , , , , , Qais Yousef Subject: [PATCH 07/14] genirq: Add a new generic IPI reservation code to irq core Date: Tue, 3 Nov 2015 11:12:54 +0000 Message-ID: <1446549181-31788-8-git-send-email-qais.yousef@imgtec.com> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1446549181-31788-1-git-send-email-qais.yousef@imgtec.com> References: <1446549181-31788-1-git-send-email-qais.yousef@imgtec.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [192.168.154.94] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add a generic mechanism to dynamically allocate an IPI. With this change the user can call irq_reserve_ipi() to dynamically allocate an IPI and use the associated virq to send one to 1 or more cpus. Signed-off-by: Qais Yousef --- include/linux/irqdomain.h | 6 +++ kernel/irq/irqdomain.c | 98 +++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 104 insertions(+) diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h index 422b6a1617b8..9ba67bfe8ad2 100644 --- a/include/linux/irqdomain.h +++ b/include/linux/irqdomain.h @@ -39,6 +39,7 @@ struct irq_domain; struct of_device_id; struct irq_chip; struct irq_data; +struct ipi_mask; /* Number of irqs reserved for a legacy isa controller */ #define NUM_ISA_INTERRUPTS 16 @@ -333,6 +334,11 @@ int irq_domain_xlate_onetwocell(struct irq_domain *d, struct device_node *ctrlr, const u32 *intspec, unsigned int intsize, irq_hw_number_t *out_hwirq, unsigned int *out_type); +/* IPI functions */ +unsigned int irq_reserve_ipi(struct irq_domain *domain, + const struct ipi_mask *dest); +void irq_destroy_ipi(unsigned int irq); + /* V2 interfaces to support hierarchy IRQ domains. */ extern struct irq_data *irq_domain_get_irq_data(struct irq_domain *domain, unsigned int virq); diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index 22aa9612ef7c..dd240914301d 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -852,6 +852,104 @@ static int irq_domain_alloc_descs(int virq, unsigned int cnt, return virq; } +/** + * irq_reserve_ipi() - setup an IPI to destination cpumask + * @domain: IPI domain + * @dest: cpumask of cpus to receive the IPI + * + * Allocate a virq that can be used to send IPI to any CPU in dest mask. + * + * On success it'll return linux irq number and 0 on failure + */ +unsigned int irq_reserve_ipi(struct irq_domain *domain, + const struct ipi_mask *dest) +{ + struct irq_data *data; + unsigned int nr_irqs; + int virq, i; + + if (domain == NULL) { + pr_warn("Must provide a valid IPI domain!\n"); + return 0; + } + + if (!irq_domain_is_ipi(domain)) { + pr_warn("Not an IPI domain!\n"); + return 0; + } + + /* always allocate a virq per cpu */ + nr_irqs = ipi_mask_weight(dest); + + virq = irq_domain_alloc_descs(-1, nr_irqs, 0, NUMA_NO_NODE); + if (virq <= 0) { + pr_warn("Can't reserve IPI, failed to alloc descs\n"); + return 0; + } + + virq = __irq_domain_alloc_irqs(domain, virq, nr_irqs, NUMA_NO_NODE, + (void *) dest, true); + if (virq <= 0) { + pr_warn("Can't reserve IPI, failed to alloc irqs\n"); + goto free_descs; + } + + for (i = virq; i < virq + nr_irqs; i++) { + data = irq_get_irq_data(i); + data->common->ipi_mask = ipi_mask_alloc(dest->nbits); + if (!data->common->ipi_mask) + goto free_ipi_mask; + ipi_mask_copy(data->common->ipi_mask, dest); + } + + return virq; + +free_ipi_mask: + for (i = virq; i < virq + nr_irqs; i++) { + data = irq_get_irq_data(i); + ipi_mask_free(data->common->ipi_mask); + } +free_descs: + irq_free_descs(virq, nr_irqs); + return 0; +} + +/** + * irq_destroy_ipi() - unreserve an IPI that was previously allocated + * @irq: linux irq number to be destroyed + * + * Return the IPIs allocated with irq_reserve_ipi() to the system destroying all + * virqs associated with them. + */ +void irq_destroy_ipi(unsigned int irq) +{ + struct irq_data *data = irq_get_irq_data(irq); + struct irq_domain *domain; + unsigned int nr_irqs, i; + + if (!irq || !data) + return; + + domain = data->domain; + if (WARN_ON(domain == NULL)) + return; + + if (!irq_domain_is_ipi(domain)) { + pr_warn("Not an IPI domain!\n"); + return; + } + + nr_irqs = ipi_mask_weight(data->common->ipi_mask); + ipi_mask_free(data->common->ipi_mask); + + for (i = irq + 1; i < irq + nr_irqs; i++) { + data = irq_get_irq_data(i); + ipi_mask_free(data->common->ipi_mask); + } + + irq_domain_free_irqs(irq, nr_irqs); +} + #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY /** * irq_domain_create_hierarchy - Add a irqdomain into the hierarchy -- 2.1.0