From patchwork Tue Nov 24 06:17:16 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexey Kardashevskiy X-Patchwork-Id: 1405284 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-gpio-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=ozlabs.ru Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4CgDbs2jqvz9sTR for ; Tue, 24 Nov 2020 17:28:09 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729188AbgKXG2I (ORCPT ); Tue, 24 Nov 2020 01:28:08 -0500 Received: from ozlabs.ru ([107.174.27.60]:51420 "EHLO ozlabs.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729552AbgKXG2H (ORCPT ); Tue, 24 Nov 2020 01:28:07 -0500 Received: from fstn1-p1.ozlabs.ibm.com (localhost [IPv6:::1]) by ozlabs.ru (Postfix) with ESMTP id 894A2AE8024F; Tue, 24 Nov 2020 01:17:57 -0500 (EST) From: Alexey Kardashevskiy To: linux-kernel@vger.kernel.org Cc: =?utf-8?q?C=C3=A9dric_Le_Goater?= , Frederic Barrat , =?utf-8?q?Michal_Such=C3=A1nek?= , "Oliver O'Halloran" , Marc Zyngier , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, linux-gpio@vger.kernel.org, x86@kernel.org, linuxppc-dev@lists.ozlabs.org, Alexey Kardashevskiy Subject: [PATCH kernel v4 4/8] genirq: Free IRQ descriptor via embedded kobject Date: Tue, 24 Nov 2020 17:17:16 +1100 Message-Id: <20201124061720.86766-5-aik@ozlabs.ru> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20201124061720.86766-1-aik@ozlabs.ru> References: <20201124061720.86766-1-aik@ozlabs.ru> Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org At the moment the IRQ descriptor is freed via the free_desc() helper. We want to add reference counting to IRQ descriptors and there is already kobj embedded into irq_desc which we want to reuse. This shuffles free_desc()/etc to make it simply call kobject_put() and moves all the cleanup into the kobject_release hook. As a bonus, we do not need irq_sysfs_del() as kobj removes itself from sysfs if it knows that it was added. This should cause no behavioral change. Signed-off-by: Alexey Kardashevskiy --- kernel/irq/irqdesc.c | 42 ++++++++++++------------------------------ 1 file changed, 12 insertions(+), 30 deletions(-) diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c index 1a7723604399..75374b7944b5 100644 --- a/kernel/irq/irqdesc.c +++ b/kernel/irq/irqdesc.c @@ -295,18 +295,6 @@ static void irq_sysfs_add(int irq, struct irq_desc *desc) } } -static void irq_sysfs_del(struct irq_desc *desc) -{ - /* - * If irq_sysfs_init() has not yet been invoked (early boot), then - * irq_kobj_base is NULL and the descriptor was never added. - * kobject_del() complains about a object with no parent, so make - * it conditional. - */ - if (irq_kobj_base) - kobject_del(&desc->kobj); -} - static int __init irq_sysfs_init(void) { struct irq_desc *desc; @@ -337,7 +325,6 @@ static struct kobj_type irq_kobj_type = { }; static void irq_sysfs_add(int irq, struct irq_desc *desc) {} -static void irq_sysfs_del(struct irq_desc *desc) {} #endif /* CONFIG_SYSFS */ @@ -419,39 +406,34 @@ static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags, return NULL; } -static void irq_kobj_release(struct kobject *kobj) -{ - struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj); - - free_masks(desc); - free_percpu(desc->kstat_irqs); - kfree(desc); -} - static void delayed_free_desc(struct rcu_head *rhp) { struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu); + free_masks(desc); + free_percpu(desc->kstat_irqs); + kfree(desc); +} + +static void free_desc(unsigned int irq) +{ + struct irq_desc *desc = irq_to_desc(irq); + kobject_put(&desc->kobj); } -static void free_desc(unsigned int irq) +static void irq_kobj_release(struct kobject *kobj) { - struct irq_desc *desc = irq_to_desc(irq); + struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj); + unsigned int irq = desc->irq_data.irq; irq_remove_debugfs_entry(desc); unregister_irq_proc(irq, desc); /* - * sparse_irq_lock protects also show_interrupts() and - * kstat_irq_usr(). Once we deleted the descriptor from the - * sparse tree we can free it. Access in proc will fail to - * lookup the descriptor. - * * The sysfs entry must be serialized against a concurrent * irq_sysfs_init() as well. */ - irq_sysfs_del(desc); delete_irq_desc(irq); /*