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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 E4558C11F66 for ; Tue, 29 Jun 2021 12:51:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CE04461DD7 for ; Tue, 29 Jun 2021 12:51:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233989AbhF2Mxr (ORCPT ); Tue, 29 Jun 2021 08:53:47 -0400 Received: from foss.arm.com ([217.140.110.172]:50418 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233291AbhF2MxV (ORCPT ); Tue, 29 Jun 2021 08:53:21 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id CF188143B; Tue, 29 Jun 2021 05:50:53 -0700 (PDT) Received: from e113632-lin.cambridge.arm.com (e113632-lin.cambridge.arm.com [10.1.194.46]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id CEFB53F718; Tue, 29 Jun 2021 05:50:52 -0700 (PDT) From: Valentin Schneider To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: Marc Zyngier , Thomas Gleixner , Lorenzo Pieralisi , Vincenzo Frascino Subject: [PATCH v3 06/13] genirq: Don't mask IRQ within flow handler if IRQ is flow-masked Date: Tue, 29 Jun 2021 13:50:03 +0100 Message-Id: <20210629125010.458872-7-valentin.schneider@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210629125010.458872-1-valentin.schneider@arm.com> References: <20210629125010.458872-1-valentin.schneider@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org mask_irq() lets an IRQ with IRQD_IRQ_FLOW_MASKED set be further masked via chip->irq_mask(). This is necessary for unhandled IRQs as we want to keep them masked beyond eoi_irq() (which clears IRQD_IRQ_FLOW_MASKED). This is however not necessary in paths that do end up handling the IRQ and are bounded by a final eoi_irq() - this is the case for chips with IRQCHIP_AUTOMASKS_FLOW and IRQCHIP_EOI_THREADED. Make handle_strict_flow_irq() leverage IRQCHIP_AUTOMASKS_FLOW and issue an ack_irq() rather than a mask_ack_irq() when possible. Signed-off-by: Valentin Schneider --- kernel/irq/chip.c | 24 ++++++++++++++++++++---- 1 file changed, 20 insertions(+), 4 deletions(-) diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index 699e70b51aae..c2ca6b748987 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -896,6 +896,12 @@ void handle_edge_eoi_irq(struct irq_desc *desc) } #endif +/* + * AUTOMASKS_FLOW tells us ack/eoi handle the masking, EOI_THREADED tells us + * that masking will persist until irq_finalize_oneshot() + */ +#define ONESHOT_AUTOMASK_FLAGS (IRQCHIP_AUTOMASKS_FLOW | IRQCHIP_EOI_THREADED) + /** * handle_strict_flow_irq - irq handler for strict controllers * @desc: the interrupt description structure for this irq @@ -909,10 +915,9 @@ void handle_strict_flow_irq(struct irq_desc *desc) struct irq_chip *chip = desc->irq_data.chip; raw_spin_lock(&desc->lock); - mask_ack_irq(desc); if (!irq_may_run(desc)) - goto out; + goto out_mask; desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); @@ -922,10 +927,20 @@ void handle_strict_flow_irq(struct irq_desc *desc) */ if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) { desc->istate |= IRQS_PENDING; - goto out; + goto out_mask; } kstat_incr_irqs_this_cpu(desc); + /* + * Masking is required if IRQ is ONESHOT and we can't rely on the + * flow-masking persisting down to irq_finalize_oneshot() + * (in the IRQ thread). + */ + if ((desc->istate & IRQS_ONESHOT) && + ((chip->flags & ONESHOT_AUTOMASK_FLAGS) != ONESHOT_AUTOMASK_FLAGS)) + mask_ack_irq(desc); + else + ack_irq(desc); handle_irq_event(desc); @@ -933,7 +948,8 @@ void handle_strict_flow_irq(struct irq_desc *desc) raw_spin_unlock(&desc->lock); return; -out: +out_mask: + mask_ack_irq(desc); /* * XXX: this is where IRQCHIP_EOI_IF_HANDLED would be checked, but * it's conceptually incompatible with this handler (it breaks the -- 2.25.1