From patchwork Mon Aug 18 15:30:32 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tomeu Vizoso X-Patchwork-Id: 4737701 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 8E86FC0338 for ; Mon, 18 Aug 2014 15:38:26 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 9D6CE20136 for ; Mon, 18 Aug 2014 15:38:25 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id A42B920120 for ; Mon, 18 Aug 2014 15:38:24 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1XJOut-0004O9-Rf; Mon, 18 Aug 2014 15:32:15 +0000 Received: from mail-lb0-x232.google.com ([2a00:1450:4010:c04::232]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1XJOuK-00045z-R3 for linux-arm-kernel@lists.infradead.org; Mon, 18 Aug 2014 15:31:42 +0000 Received: by mail-lb0-f178.google.com with SMTP id c11so4271567lbj.23 for ; Mon, 18 Aug 2014 08:31:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references; bh=IT6lP3hGrwrlx7H6E49LnqG2K3CBRvACdvfuc3iaYWM=; b=Y6rzEYNBQEDmHZ6Q2JoWTvb3hnYIKumVzpukC4t833TBIcpKUaUO0k/fooPmSwfrr1 9bMAgUvcXK97EVOKdk5nhOi8iUApBpP0hfcdDoTBNp+yl9MUcSecbuZfDWBbvgbFZ9Yv AnyMUoV93wRVNVHOyIjjswOBRRZAalUotVP/cljURFQOmBViG6brZWWNcjWZ+US+p67o NEsY2VMIlW8RIfOJZd/yFeRI/mbfGpKN8q9Ril6oSzAIZbmGz5mGemWJuwssFEC95/UP k4Iow1aGnR2GlODbj/tUzvMLz7tnoCJ+XTfVFCy2se5QBm2IuO6ZokohX/uft8PmmVQ1 kd4w== X-Received: by 10.112.166.2 with SMTP id zc2mr3601228lbb.98.1408375877699; Mon, 18 Aug 2014 08:31:17 -0700 (PDT) Received: from cizrna.lan (37-48-35-72.tmcz.cz. [37.48.35.72]) by mx.google.com with ESMTPSA id q7sm1793990lag.16.2014.08.18.08.31.15 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 18 Aug 2014 08:31:16 -0700 (PDT) From: Tomeu Vizoso To: Mike Turquette Subject: [PATCH v7 7/8] clk: per-user clock accounting for debug Date: Mon, 18 Aug 2014 17:30:32 +0200 Message-Id: <1408375833-10703-7-git-send-email-tomeu.vizoso@collabora.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1408375833-10703-1-git-send-email-tomeu.vizoso@collabora.com> References: <1408375833-10703-1-git-send-email-tomeu.vizoso@collabora.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140818_083141_096037_6DE81AB1 X-CRM114-Status: GOOD ( 16.93 ) X-Spam-Score: 0.0 (/) Cc: Tomeu Vizoso , Stephen Warren , Tomasz Figa , linux-kernel@vger.kernel.org, Javier Martinez Canillas , rabin@rab.in, Thierry Reding , Peter De Schrijver , linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-2.5 required=5.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_NONE,RP_MATCHES_RCVD,T_DKIM_INVALID,UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP When a clock has multiple users, the WARNING on imbalance of enable/disable may not show the guilty party since although they may have commited the error earlier, the warning is emitted later when some other user, presumably innocent, disables the clock. Provide per-user clock enable/disable accounting and disabler tracking in order to help debug these problems. Based on previous work by Rabin Vincent . Signed-off-by: Tomeu Vizoso --- drivers/clk/clk.c | 38 ++++++++++++++++++++++++++++++++++---- drivers/clk/clk.h | 3 ++- drivers/clk/clkdev.c | 12 ++++++++---- include/linux/clk-private.h | 4 ++++ 4 files changed, 48 insertions(+), 9 deletions(-) diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index a2d0ee5..f94c444 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -543,7 +543,8 @@ static int clk_disable_unused(void) } late_initcall_sync(clk_disable_unused); -struct clk *__clk_create_clk(struct clk_core *clk_core) +struct clk *__clk_create_clk(struct clk_core *clk_core, const char *dev, + const char *con) { struct clk *clk; @@ -556,6 +557,8 @@ struct clk *__clk_create_clk(struct clk_core *clk_core) return ERR_PTR(-ENOMEM); clk->core = clk_core; + clk->dev_id = dev; + clk->con_id = con; return clk; } @@ -936,10 +939,25 @@ EXPORT_SYMBOL_GPL(clk_provider_disable); */ void clk_disable(struct clk *clk_user) { + struct clk_core *clk; + unsigned long flags; + if (IS_ERR_OR_NULL(clk_user)) return; - clk_provider_disable(clk_to_clk_core(clk_user)); + clk = clk_to_clk_core(clk_user); + + flags = clk_enable_lock(); + if (!WARN(clk_user->enable_count == 0, + "incorrect disable clk dev %s con %s last disabler %pF\n", + clk_user->dev_id, clk_user->con_id, clk_user->last_disable)) { + + clk_user->last_disable = __builtin_return_address(0); + clk_user->enable_count--; + + __clk_disable(clk); + } + clk_enable_unlock(flags); } EXPORT_SYMBOL_GPL(clk_disable); @@ -1000,10 +1018,22 @@ EXPORT_SYMBOL_GPL(clk_provider_enable); */ int clk_enable(struct clk *clk_user) { + struct clk_core *clk; + unsigned long flags; + int ret; + if (!clk_user) return 0; - return clk_provider_enable(clk_to_clk_core(clk_user)); + clk = clk_to_clk_core(clk_user); + + flags = clk_enable_lock(); + ret = __clk_enable(clk); + if (!ret) + clk_user->enable_count++; + clk_enable_unlock(flags); + + return ret; } EXPORT_SYMBOL_GPL(clk_enable); @@ -1719,7 +1749,7 @@ struct clk *clk_get_parent(struct clk *clk_user) clk = clk_to_clk_core(clk_user); parent = clk_provider_get_parent(clk); - return __clk_create_clk(parent); + return __clk_create_clk(parent, clk_user->dev_id, clk_user->con_id); } EXPORT_SYMBOL_GPL(clk_get_parent); diff --git a/drivers/clk/clk.h b/drivers/clk/clk.h index 3b3068b..49eff38 100644 --- a/drivers/clk/clk.h +++ b/drivers/clk/clk.h @@ -19,5 +19,6 @@ void of_clk_unlock(void); #endif #if defined(CONFIG_COMMON_CLK) -struct clk *__clk_create_clk(struct clk_core *clk_core); +struct clk *__clk_create_clk(struct clk_core *clk_core, const char *dev, + const char *con); #endif diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c index 810935f..0752cc9 100644 --- a/drivers/clk/clkdev.c +++ b/drivers/clk/clkdev.c @@ -76,7 +76,9 @@ struct clk_core *of_clk_provider_get(struct device_node *np, int index) struct clk *of_clk_get(struct device_node *np, int index) { - return __clk_create_clk(of_clk_provider_get(np, index)); + struct clk_core *clk = of_clk_provider_get(np, index); + + return __clk_create_clk(clk, np->full_name, NULL); } EXPORT_SYMBOL(of_clk_get); @@ -129,7 +131,9 @@ struct clk_core *of_clk_provider_get_by_name(struct device_node *np, const char */ struct clk *of_clk_get_by_name(struct device_node *np, const char *name) { - return __clk_create_clk(of_clk_provider_get_by_name(np, name)); + struct clk_core *clk = of_clk_provider_get_by_name(np, name); + + return __clk_create_clk(clk, np->full_name, NULL); } EXPORT_SYMBOL(of_clk_get_by_name); #endif @@ -201,7 +205,7 @@ struct clk *clk_get_sys(const char *dev_id, const char *con_id) #if defined(CONFIG_COMMON_CLK) struct clk_core *clk = clk_provider_get_sys(dev_id, con_id); - return __clk_create_clk(clk); + return __clk_create_clk(clk, dev_id, con_id); #else struct clk_lookup *cl; @@ -243,7 +247,7 @@ struct clk *clk_get(struct device *dev, const char *con_id) #if defined(CONFIG_COMMON_CLK) const char *dev_id = dev ? dev_name(dev) : NULL; - return __clk_create_clk(clk_provider_get(dev, con_id)); + return __clk_create_clk(clk_provider_get(dev, con_id), dev_id, con_id); #else const char *dev_id = dev ? dev_name(dev) : NULL; struct clk *clk; diff --git a/include/linux/clk-private.h b/include/linux/clk-private.h index 2c1ece9..9657fc8 100644 --- a/include/linux/clk-private.h +++ b/include/linux/clk-private.h @@ -57,6 +57,10 @@ struct clk_core { struct clk { struct clk_core *core; + unsigned int enable_count; + const char *dev_id; + const char *con_id; + void *last_disable; }; /*