From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753326AbdFTAAf (ORCPT ); Mon, 19 Jun 2017 20:00:35 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:40259 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753277AbdFTAAa (ORCPT ); Mon, 19 Jun 2017 20:00:30 -0400 Message-Id: <20170619235447.112094565@linutronix.de> User-Agent: quilt/0.63-1 Date: Tue, 20 Jun 2017 01:37:49 +0200 From: Thomas Gleixner To: LKML Cc: Marc Zyngier , Christoph Hellwig , Ingo Molnar , Peter Zijlstra , Michael Ellerman , Jens Axboe , Keith Busch Subject: [patch 49/55] genirq: Add force argument to irq_startup() References: <20170619233700.547167146@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Disposition: inline; filename=genirq--Add-force-argument-to-irq_startup--.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In order to handle managed interrupts gracefully on irq_startup() so they won't lose their assigned affinity, it's necessary to allow startups which keep the interrupts in managed shutdown state, if none of the assigend CPUs is online. This allows drivers to request interrupts w/o the CPUs being online, which avoid online/offline churn in drivers. Add a force argument which can override that decision and let only request_irq() and enable_irq() allow the managed shutdown handling. enable_irq() is required, because the interrupt might be requested with IRQF_NOAUTOEN and enable_irq() invokes irq_startup() which would then wreckage the assignment again. All other callers force startup and potentially break the assigned affinity. No functional change as this only adds the function argument. Signed-off-by: Thomas Gleixner --- kernel/irq/autoprobe.c | 4 ++-- kernel/irq/chip.c | 4 ++-- kernel/irq/internals.h | 9 ++++++++- kernel/irq/manage.c | 4 ++-- 4 files changed, 14 insertions(+), 7 deletions(-) --- a/kernel/irq/autoprobe.c +++ b/kernel/irq/autoprobe.c @@ -53,7 +53,7 @@ unsigned long probe_irq_on(void) if (desc->irq_data.chip->irq_set_type) desc->irq_data.chip->irq_set_type(&desc->irq_data, IRQ_TYPE_PROBE); - irq_startup(desc, false); + irq_startup(desc, IRQ_NORESEND, IRQ_START_FORCE); } raw_spin_unlock_irq(&desc->lock); } @@ -70,7 +70,7 @@ unsigned long probe_irq_on(void) raw_spin_lock_irq(&desc->lock); if (!desc->action && irq_settings_can_probe(desc)) { desc->istate |= IRQS_AUTODETECT | IRQS_WAITING; - if (irq_startup(desc, false)) + if (irq_startup(desc, IRQ_NORESEND, IRQ_START_FORCE)) desc->istate |= IRQS_PENDING; } raw_spin_unlock_irq(&desc->lock); --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -212,7 +212,7 @@ static int __irq_startup(struct irq_desc return ret; } -int irq_startup(struct irq_desc *desc, bool resend) +int irq_startup(struct irq_desc *desc, bool resend, bool force) { int ret = 0; @@ -892,7 +892,7 @@ static void irq_settings_set_norequest(desc); irq_settings_set_nothread(desc); desc->action = &chained_action; - irq_startup(desc, true); + irq_startup(desc, IRQ_RESEND, IRQ_START_FORCE); } } --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -66,7 +66,14 @@ extern int __irq_set_trigger(struct irq_ extern void __disable_irq(struct irq_desc *desc); extern void __enable_irq(struct irq_desc *desc); -extern int irq_startup(struct irq_desc *desc, bool resend); +#define IRQ_RESEND true +#define IRQ_NORESEND false + +#define IRQ_START_FORCE true +#define IRQ_START_COND false + +extern int irq_startup(struct irq_desc *desc, bool resend, bool force); + extern void irq_shutdown(struct irq_desc *desc); extern void irq_enable(struct irq_desc *desc); extern void irq_disable(struct irq_desc *desc); --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -509,7 +509,7 @@ void __enable_irq(struct irq_desc *desc) * time. If it was already started up, then irq_startup() * will invoke irq_enable() under the hood. */ - irq_startup(desc, true); + irq_startup(desc, IRQ_RESEND, IRQ_START_COND); break; } default: @@ -1304,7 +1304,7 @@ static int } if (irq_settings_can_autoenable(desc)) { - irq_startup(desc, true); + irq_startup(desc, IRQ_RESEND, IRQ_START_COND); } else { /* * Shared interrupts do not go well with disabling