From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1C2D4C433F4 for ; Tue, 18 Sep 2018 16:37:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CB2F8214DD for ; Tue, 18 Sep 2018 16:37:34 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CB2F8214DD Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=zytor.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730362AbeIRWKz (ORCPT ); Tue, 18 Sep 2018 18:10:55 -0400 Received: from terminus.zytor.com ([198.137.202.136]:55841 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728982AbeIRWKy (ORCPT ); Tue, 18 Sep 2018 18:10:54 -0400 Received: from terminus.zytor.com (localhost [127.0.0.1]) by terminus.zytor.com (8.15.2/8.15.2) with ESMTPS id w8IGbPQA848179 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Tue, 18 Sep 2018 09:37:26 -0700 Received: (from tipbot@localhost) by terminus.zytor.com (8.15.2/8.15.2/Submit) id w8IGbP6L848176; Tue, 18 Sep 2018 09:37:25 -0700 Date: Tue, 18 Sep 2018 09:37:25 -0700 X-Authentication-Warning: terminus.zytor.com: tipbot set sender to tipbot@zytor.com using -f From: tip-bot for Dou Liyang Message-ID: Cc: linux-kernel@vger.kernel.org, tglx@linutronix.de, hpa@zytor.com, douly.fnst@cn.fujitsu.com, mingo@kernel.org Reply-To: douly.fnst@cn.fujitsu.com, mingo@kernel.org, hpa@zytor.com, tglx@linutronix.de, linux-kernel@vger.kernel.org In-Reply-To: <20180908175838.14450-2-dou_liyang@163.com> References: <20180908175838.14450-2-dou_liyang@163.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/apic] irq/matrix: Spread managed interrupts on allocation Git-Commit-ID: 76f99ae5b54d48430d1f0c5512a84da0ff9761e0 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 76f99ae5b54d48430d1f0c5512a84da0ff9761e0 Gitweb: https://git.kernel.org/tip/76f99ae5b54d48430d1f0c5512a84da0ff9761e0 Author: Dou Liyang AuthorDate: Sun, 9 Sep 2018 01:58:38 +0800 Committer: Thomas Gleixner CommitDate: Tue, 18 Sep 2018 18:27:24 +0200 irq/matrix: Spread managed interrupts on allocation Linux spreads out the non managed interrupt across the possible target CPUs to avoid vector space exhaustion. Managed interrupts are treated differently, as for them the vectors are reserved (with guarantee) when the interrupt descriptors are initialized. When the interrupt is requested a real vector is assigned. The assignment logic uses the first CPU in the affinity mask for assignment. If the interrupt has more than one CPU in the affinity mask, which happens when a multi queue device has less queues than CPUs, then doing the same search as for non managed interrupts makes sense as it puts the interrupt on the least interrupt plagued CPU. For single CPU affine vectors that's obviously a NOOP. Restructre the matrix allocation code so it does the 'best CPU' search, add the sanity check for an empty affinity mask and adapt the call site in the x86 vector management code. [ tglx: Added the empty mask check to the core and improved change log ] Signed-off-by: Dou Liyang Signed-off-by: Thomas Gleixner Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/20180908175838.14450-2-dou_liyang@163.com --- arch/x86/kernel/apic/vector.c | 9 ++++----- include/linux/irq.h | 3 ++- kernel/irq/matrix.c | 17 ++++++++++++++--- 3 files changed, 20 insertions(+), 9 deletions(-) diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c index 7654febd5102..652e7ffa9b9d 100644 --- a/arch/x86/kernel/apic/vector.c +++ b/arch/x86/kernel/apic/vector.c @@ -313,14 +313,13 @@ assign_managed_vector(struct irq_data *irqd, const struct cpumask *dest) struct apic_chip_data *apicd = apic_chip_data(irqd); int vector, cpu; - cpumask_and(vector_searchmask, vector_searchmask, affmsk); - cpu = cpumask_first(vector_searchmask); - if (cpu >= nr_cpu_ids) - return -EINVAL; + cpumask_and(vector_searchmask, dest, affmsk); + /* set_affinity might call here for nothing */ if (apicd->vector && cpumask_test_cpu(apicd->cpu, vector_searchmask)) return 0; - vector = irq_matrix_alloc_managed(vector_matrix, cpu); + vector = irq_matrix_alloc_managed(vector_matrix, vector_searchmask, + &cpu); trace_vector_alloc_managed(irqd->irq, vector, vector); if (vector < 0) return vector; diff --git a/include/linux/irq.h b/include/linux/irq.h index 201de12a9957..c9bffda04a45 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -1151,7 +1151,8 @@ void irq_matrix_offline(struct irq_matrix *m); void irq_matrix_assign_system(struct irq_matrix *m, unsigned int bit, bool replace); int irq_matrix_reserve_managed(struct irq_matrix *m, const struct cpumask *msk); void irq_matrix_remove_managed(struct irq_matrix *m, const struct cpumask *msk); -int irq_matrix_alloc_managed(struct irq_matrix *m, unsigned int cpu); +int irq_matrix_alloc_managed(struct irq_matrix *m, const struct cpumask *msk, + unsigned int *mapped_cpu); void irq_matrix_reserve(struct irq_matrix *m); void irq_matrix_remove_reserved(struct irq_matrix *m); int irq_matrix_alloc(struct irq_matrix *m, const struct cpumask *msk, diff --git a/kernel/irq/matrix.c b/kernel/irq/matrix.c index 67768bbe736e..6e6d467f3dec 100644 --- a/kernel/irq/matrix.c +++ b/kernel/irq/matrix.c @@ -260,11 +260,21 @@ void irq_matrix_remove_managed(struct irq_matrix *m, const struct cpumask *msk) * @m: Matrix pointer * @cpu: On which CPU the interrupt should be allocated */ -int irq_matrix_alloc_managed(struct irq_matrix *m, unsigned int cpu) +int irq_matrix_alloc_managed(struct irq_matrix *m, const struct cpumask *msk, + unsigned int *mapped_cpu) { - struct cpumap *cm = per_cpu_ptr(m->maps, cpu); - unsigned int bit, end = m->alloc_end; + unsigned int bit, cpu, end = m->alloc_end; + struct cpumap *cm; + + if (cpumask_empty(msk)) + return -EINVAL; + cpu = matrix_find_best_cpu(m, msk); + if (cpu == UINT_MAX) + return -ENOSPC; + + cm = per_cpu_ptr(m->maps, cpu); + end = m->alloc_end; /* Get managed bit which are not allocated */ bitmap_andnot(m->scratch_map, cm->managed_map, cm->alloc_map, end); bit = find_first_bit(m->scratch_map, end); @@ -273,6 +283,7 @@ int irq_matrix_alloc_managed(struct irq_matrix *m, unsigned int cpu) set_bit(bit, cm->alloc_map); cm->allocated++; m->total_allocated++; + *mapped_cpu = cpu; trace_irq_matrix_alloc_managed(bit, cpu, m, cm); return bit; }