From patchwork Thu Jul 11 23:43:58 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joel Fernandes X-Patchwork-Id: 1131077 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=joelfernandes.org Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=joelfernandes.org header.i=@joelfernandes.org header.b="ZR89dJ0g"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 45lCMw5D6Lz9s4Y for ; Fri, 12 Jul 2019 09:45:00 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729612AbfGKXo5 (ORCPT ); Thu, 11 Jul 2019 19:44:57 -0400 Received: from mail-pf1-f193.google.com ([209.85.210.193]:39644 "EHLO mail-pf1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730476AbfGKXo1 (ORCPT ); Thu, 11 Jul 2019 19:44:27 -0400 Received: by mail-pf1-f193.google.com with SMTP id j2so3461773pfe.6 for ; Thu, 11 Jul 2019 16:44:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=DxaBT1tnbAEQu4unrE+ZIdJanB1uVhDn4/7rfKQHrQ8=; b=ZR89dJ0gCvmFd48H56kuCm2XzQpnVhPx64wtgiHyZvxa33ANSu0oXUTttSIxFI0x9Z fHKlA+45Bqn3L3g08DQds8w60ml29tD/QN8R/vX0Ix2Z2Akl/LzUSDrgZDI4Q/+otrRY I+DBueCyfUEugUlr0uSGpkRYwIAjZJZdHOtgc= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=DxaBT1tnbAEQu4unrE+ZIdJanB1uVhDn4/7rfKQHrQ8=; b=N8R02lgYALYxmJKgi3u6kgiGZ1kYJhUyz44w5djEwf7/6PA2kCrAEM6iZ0tXuNf15l R1WGLstRaahrl1y/0X+/r0qd64IwfD2ryULSwakI9AJOrm7tph/gIE8WixKjwHZHy3vs 78giOluw9FIPGplnMCrs97xbjAAS7B6gpxuh8TtzT4OqOPNJmGnEsvtgV2dXkVqNuQnw Olmi0/yMXd2jlE9VgJD5K2gACwIBerRUDcoWkJNvk3P3ue4e77QQrJEd2Jtt9qIH9xXO yyytPahBGcS8Vmf7ERdnQ99jT2COsO0sv8laCtByAbJwKIa+SGFUpDNgqL03gKNQLLkX VbPA== X-Gm-Message-State: APjAAAXbByiG3BP367HFgv+zPD/xl9RguD/ht+CReRpRUnJSD2o7s9Mt aKVej3nM4QEjcAd05xSJzME= X-Google-Smtp-Source: APXvYqzUKLrrGWpDYD2bC1yFQhR2A3bxbRxsjgXB3UX8GkC2wLperL0TYvgWXgyR72s0kBdwkN7Ihw== X-Received: by 2002:a63:5212:: with SMTP id g18mr2790151pgb.387.1562888666095; Thu, 11 Jul 2019 16:44:26 -0700 (PDT) Received: from joelaf.cam.corp.google.com ([2620:15c:6:12:9c46:e0da:efbf:69cc]) by smtp.gmail.com with ESMTPSA id t10sm6163450pjr.13.2019.07.11.16.44.22 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Thu, 11 Jul 2019 16:44:25 -0700 (PDT) From: "Joel Fernandes (Google)" To: linux-kernel@vger.kernel.org Cc: "Joel Fernandes (Google)" , Alexey Kuznetsov , Bjorn Helgaas , Borislav Petkov , c0d1n61at3@gmail.com, "David S. Miller" , edumazet@google.com, Greg Kroah-Hartman , Hideaki YOSHIFUJI , "H. Peter Anvin" , Ingo Molnar , Josh Triplett , keescook@chromium.org, kernel-hardening@lists.openwall.com, Lai Jiangshan , Len Brown , linux-acpi@vger.kernel.org, linux-pci@vger.kernel.org, linux-pm@vger.kernel.org, Mathieu Desnoyers , neilb@suse.com, netdev@vger.kernel.org, oleg@redhat.com, "Paul E. McKenney" , Pavel Machek , peterz@infradead.org, "Rafael J. Wysocki" , Rasmus Villemoes , rcu@vger.kernel.org, Steven Rostedt , Tejun Heo , Thomas Gleixner , will@kernel.org, x86@kernel.org (maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)) Subject: [PATCH v1 3/6] driver/core: Convert to use built-in RCU list checking Date: Thu, 11 Jul 2019 19:43:58 -0400 Message-Id: <20190711234401.220336-4-joel@joelfernandes.org> X-Mailer: git-send-email 2.22.0.410.gd8fdbe21b5-goog In-Reply-To: <20190711234401.220336-1-joel@joelfernandes.org> References: <20190711234401.220336-1-joel@joelfernandes.org> MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org list_for_each_entry_rcu has built-in RCU and lock checking. Make use of it in driver core. Signed-off-by: Joel Fernandes (Google) Acked-by: Greg Kroah-Hartman --- drivers/base/base.h | 1 + drivers/base/core.c | 10 ++++++++++ drivers/base/power/runtime.c | 15 ++++++++++----- 3 files changed, 21 insertions(+), 5 deletions(-) diff --git a/drivers/base/base.h b/drivers/base/base.h index b405436ee28e..0d32544b6f91 100644 --- a/drivers/base/base.h +++ b/drivers/base/base.h @@ -165,6 +165,7 @@ static inline int devtmpfs_init(void) { return 0; } /* Device links support */ extern int device_links_read_lock(void); extern void device_links_read_unlock(int idx); +extern int device_links_read_lock_held(void); extern int device_links_check_suppliers(struct device *dev); extern void device_links_driver_bound(struct device *dev); extern void device_links_driver_cleanup(struct device *dev); diff --git a/drivers/base/core.c b/drivers/base/core.c index fd7511e04e62..6c5ca9685647 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -68,6 +68,11 @@ void device_links_read_unlock(int idx) { srcu_read_unlock(&device_links_srcu, idx); } + +int device_links_read_lock_held(void) +{ + return srcu_read_lock_held(&device_links_srcu); +} #else /* !CONFIG_SRCU */ static DECLARE_RWSEM(device_links_lock); @@ -91,6 +96,11 @@ void device_links_read_unlock(int not_used) { up_read(&device_links_lock); } + +int device_links_read_lock_held(void) +{ + return lock_is_held(&device_links_lock); +} #endif /* !CONFIG_SRCU */ /** diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index 952a1e7057c7..7a10e8379a70 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -287,7 +287,8 @@ static int rpm_get_suppliers(struct device *dev) { struct device_link *link; - list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) { + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node, + device_links_read_lock_held()) { int retval; if (!(link->flags & DL_FLAG_PM_RUNTIME) || @@ -309,7 +310,8 @@ static void rpm_put_suppliers(struct device *dev) { struct device_link *link; - list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) { + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node, + device_links_read_lock_held()) { if (READ_ONCE(link->status) == DL_STATE_SUPPLIER_UNBIND) continue; @@ -1640,7 +1642,8 @@ void pm_runtime_clean_up_links(struct device *dev) idx = device_links_read_lock(); - list_for_each_entry_rcu(link, &dev->links.consumers, s_node) { + list_for_each_entry_rcu(link, &dev->links.consumers, s_node, + device_links_read_lock_held()) { if (link->flags & DL_FLAG_STATELESS) continue; @@ -1662,7 +1665,8 @@ void pm_runtime_get_suppliers(struct device *dev) idx = device_links_read_lock(); - list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node, + device_links_read_lock_held()) if (link->flags & DL_FLAG_PM_RUNTIME) { link->supplier_preactivated = true; refcount_inc(&link->rpm_active); @@ -1683,7 +1687,8 @@ void pm_runtime_put_suppliers(struct device *dev) idx = device_links_read_lock(); - list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node, + device_links_read_lock_held()) if (link->supplier_preactivated) { link->supplier_preactivated = false; if (refcount_dec_not_one(&link->rpm_active))