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 Received: from mail.librecores.org (lists.librecores.org [88.198.125.70]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1A6AAC43334 for ; Fri, 17 Jun 2022 00:04:23 +0000 (UTC) Received: from [172.31.1.100] (localhost.localdomain [127.0.0.1]) by mail.librecores.org (Postfix) with ESMTP id C552F20D93; Fri, 17 Jun 2022 02:04:22 +0200 (CEST) Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by mail.librecores.org (Postfix) with ESMTPS id E5603247EA for ; Thu, 16 Jun 2022 23:23:07 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1655414588; x=1686950588; h=date:from:to:cc:subject:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=eIVB2Wcg0d4KNkOlM5BOJs0iOIDhUm5jxxQVobMAAIM=; b=W5aCItJRES/4K/8kBAqYbm9fTxOTAVg6DVo5f3CXG07GixSWEekSlxi/ /ECVaXt1EWBHhXzmcCFEnsCdzpisrntvcuTBkvFlHFCY2MYLYN74JdtIW 4OOhU/Lvia9oeOFB57V4PEWsSojNzswPvkh8tmE388Ha1Ru/mNBUG9Fmx Dm+Zue7ICYVIkgvA09io/ZlFIbj3UdrTnFYZpk22Ck4589V9jOCiSUOJt j+hnqXcn15wHw0TP2TtPzWn8/BOHMpU3y8iXpjR4F4vYtVUDPe5qJGus/ IQXbVXHXBCtA8NWjqgD8bIKEwig/+uSDECutNlMEfXcOeUdsYL+AslSW9 A==; X-IronPort-AV: E=McAfee;i="6400,9594,10380"; a="343316065" X-IronPort-AV: E=Sophos;i="5.92,306,1650956400"; d="scan'208";a="343316065" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Jun 2022 14:22:51 -0700 X-IronPort-AV: E=Sophos;i="5.92,306,1650956400"; d="scan'208";a="560027674" Received: from jacob-builder.jf.intel.com (HELO jacob-builder) ([10.7.198.157]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Jun 2022 14:22:51 -0700 Date: Thu, 16 Jun 2022 14:26:56 -0700 From: Jacob Pan To: Peter Zijlstra Subject: Re: [PATCH 04/36] cpuidle,intel_idle: Fix CPUIDLE_FLAG_IRQ_ENABLE Message-ID: <20220616142656.4b1acc4a@jacob-builder> In-Reply-To: References: <20220608142723.103523089@infradead.org> <20220608144516.172460444@infradead.org> <20220609164921.5e61711d@jacob-builder> Organization: OTC X-Mailer: Claws Mail 3.17.5 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Mailman-Approved-At: Fri, 17 Jun 2022 02:04:20 +0200 X-BeenThere: openrisc@lists.librecores.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: Discussion around the OpenRISC processor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: juri.lelli@redhat.com, rafael@kernel.org, benh@kernel.crashing.org, linus.walleij@linaro.org, bsegall@google.com, guoren@kernel.org, pavel@ucw.cz, agordeev@linux.ibm.com, srivatsa@csail.mit.edu, linux-arch@vger.kernel.org, vincent.guittot@linaro.org, mpe@ellerman.id.au, chenhuacai@kernel.org, linux-acpi@vger.kernel.org, agross@kernel.org, linux-imx@nxp.com, catalin.marinas@arm.com, xen-devel@lists.xenproject.org, mattst88@gmail.com, borntraeger@linux.ibm.com, mturquette@baylibre.com, sammy@sammy.net, pmladek@suse.com, linux-pm@vger.kernel.org, jiangshanlai@gmail.com, Sascha Hauer , linux-um@lists.infradead.org, acme@kernel.org, tglx@linutronix.de, linux-omap@vger.kernel.org, dietmar.eggemann@arm.com, rth@twiddle.net, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, senozhatsky@chromium.org, svens@linux.ibm.com, jolsa@kernel.org, paulus@samba.org, mark.rutland@arm.com, linux-ia64@vger.kernel.org, dave.hansen@linux.intel.com, virtualization@lists.linux-foundation.org, James.Bottomley@hansenpartnership.com, jcmvbkbc@gmail.com, thierry.reding@gmail.com, kernel@xen0n.name, quic_neeraju@quicinc.com, linux-s390@vger.kernel.org, vschneid@redhat.com, john.ogness@linutronix.de, ysato@users.sourceforge.jp, linux-sh@vger.kernel.org, festevam@gmail.com, deller@gmx.de, daniel.lezcano@linaro.org, jonathanh@nvidia.com, mathieu.desnoyers@efficios.com, frederic@kernel.org, lenb@kernel.org, linux-xtensa@linux-xtensa.org, kernel@pengutronix.de, gor@linux.ibm.com, linux-arm-msm@vger.kernel.org, linux-alpha@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-arm-kernel@lists.infradead.org, chris@zankel.net, sboyd@kernel.org, dinguyen@kernel.org, bristot@redhat.com, alexander.shishkin@linux.intel.com, lpieralisi@kernel.org, linux@rasmusvillemoes.dk, joel@joelfernandes.org, will@kernel.org, boris.ostrovsky@oracle.com, khilman@kernel.org, linux-csky@vger.kernel.org, pv-drivers@vmware.com, linux-snps-arc@lists.infradead.org, mgorman@suse.de, jacob.jun.pan@linux.intel.com, Arnd Bergmann , ulli.kroll@googlemail.com, vgupta@kernel.org, linux-clk@vger.kernel.org, josh@joshtriplett.org, rostedt@goodmis.org, rcu@vger.kernel.org, bp@alien8.de, bcain@quicinc.com, tsbogend@alpha.franken.de, linux-parisc@vger.kernel.org, sudeep.holla@arm.com, shawnguo@kernel.org, davem@davemloft.net, dalias@libc.org, tony@atomide.com, amakhalov@vmware.com, bjorn.andersson@linaro.org, hpa@zytor.com, sparclinux@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-riscv@lists.infradead.org, anton.ivanov@cambridgegreys.com, jonas@southpole.se, yury.norov@gmail.com, richard@nod.at, x86@kernel.org, linux@armlinux.org.uk, mingo@redhat.com, aou@eecs.berkeley.edu, paulmck@kernel.org, hca@linux.ibm.com, openrisc@lists.librecores.org, paul.walmsley@sifive.com, linux-tegra@vger.kernel.org, namhyung@kernel.org, andriy.shevchenko@linux.intel.com, jpoimboe@kernel.org, jgross@suse.com, monstr@monstr.eu, linux-mips@vger.kernel.org, palmer@dabbelt.com, anup@brainfault.org, ink@jurassic.park.msu.ru, johannes@sipsolutions.net, linuxppc-dev@lists.ozlabs.org Errors-To: openrisc-bounces@lists.librecores.org Sender: "OpenRISC" Hi Peter, On Mon, 13 Jun 2022 10:44:22 +0200, Peter Zijlstra wrote: > On Thu, Jun 09, 2022 at 04:49:21PM -0700, Jacob Pan wrote: > > Hi Peter, > > > > On Wed, 08 Jun 2022 16:27:27 +0200, Peter Zijlstra > > wrote: > > > > > Commit c227233ad64c ("intel_idle: enable interrupts before C1 on > > > Xeons") wrecked intel_idle in two ways: > > > > > > - must not have tracing in idle functions > > > - must return with IRQs disabled > > > > > > Additionally, it added a branch for no good reason. > > > > > > Fixes: c227233ad64c ("intel_idle: enable interrupts before C1 on > > > Xeons") Signed-off-by: Peter Zijlstra (Intel) > > > --- > > > drivers/idle/intel_idle.c | 48 > > > +++++++++++++++++++++++++++++++++++----------- 1 file changed, 37 > > > insertions(+), 11 deletions(-) > > > > > > --- a/drivers/idle/intel_idle.c > > > +++ b/drivers/idle/intel_idle.c > > > @@ -129,21 +137,37 @@ static unsigned int mwait_substates __in > > > * > > > * Must be called under local_irq_disable(). > > > */ > > nit: this comment is no long true, right? > > It still is, all the idle routines are called with interrupts disabled, > but must also exit with interrupts disabled. > > If the idle method requires interrupts to be enabled, it must be sure to > disable them again before returning. Given all the RCU/tracing concerns > it must use raw_local_irq_*() for this though. Makes sense, it is just little confusing when the immediate caller does raw_local_irq_enable() which does not cancel out local_irq_disable(). Thanks, Jacob