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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5044DCCA473 for ; Thu, 9 Jun 2022 09:41:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242855AbiFIJlX (ORCPT ); Thu, 9 Jun 2022 05:41:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46944 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242254AbiFIJlT (ORCPT ); Thu, 9 Jun 2022 05:41:19 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6B3F14B40B; Thu, 9 Jun 2022 02:41:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=jxhFyRA7gcpqWtRQyvyD3abswc2PbVc4FSoswUV5Ukc=; b=eTVis02Li1gUMyvYNvhtQOfPjM 7jPK+tlnMQu8YlONdKYuGGzg5f4OtA6n+DLuvaVtWLmmwBKEcjK3gJJFZyuUsx9s+WrgcdXDtEGo5 n/0BitYa/9Tv9a5PHDy4FBaJ0usEOIIGYMMcR/SAKx38GPSteGLT2qjJKdgzgVt9Wb+/EeSMk/GCj o7MIldwwpKDLAKlNGDE/FUzTM2RKPEJfDUWHFxb549VYWV718uWBpBWrwfwVc4Y51nI2XmOQdPNke dbtUv13RdN1xprVJqbJ/lLZKhjUqu4j3NGqJXLsSZjtm/Jap7nXVhvEByTNVwWiNq35HcNs4n5id9 tqC7XoNQ==; Received: from dhcp-077-249-017-003.chello.nl ([77.249.17.3] helo=worktop.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1nzEen-006Kx6-EP; Thu, 09 Jun 2022 09:40:50 +0000 Received: by worktop.programming.kicks-ass.net (Postfix, from userid 1000) id B092F981287; Thu, 9 Jun 2022 11:40:46 +0200 (CEST) Date: Thu, 9 Jun 2022 11:40:46 +0200 From: Peter Zijlstra To: Arnd Bergmann Cc: Richard Henderson , Ivan Kokshaysky , Matt Turner , Vineet Gupta , Russell King - ARM Linux , Hans Ulli Kroll , Linus Walleij , Shawn Guo , Sascha Hauer , Sascha Hauer , Fabio Estevam , NXP Linux Team , Tony Lindgren , Kevin Hilman , Catalin Marinas , Will Deacon , Guo Ren , bcain@quicinc.com, Huacai Chen , Xuerui Wang , Geert Uytterhoeven , Sam Creasey , Michal Simek , Thomas Bogendoerfer , Dinh Nguyen , Jonas Bonn , Stefan Kristiansson , Stafford Horne , James Bottomley , Helge Deller , Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , Paul Walmsley , Palmer Dabbelt , Albert Ou , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Yoshinori Sato , Rich Felker , David Miller , Richard Weinberger , Anton Ivanov , Johannes Berg , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , the arch/x86 maintainers , "H. Peter Anvin" , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Juergen Gross , srivatsa@csail.mit.edu, amakhalov@vmware.com, Pv-drivers , Boris Ostrovsky , Chris Zankel , Max Filippov , Rafael Wysocki , Len Brown , Pavel Machek , gregkh , Michael Turquette , Stephen Boyd , Daniel Lezcano , lpieralisi@kernel.org, Sudeep Holla , Andy Gross , Bjorn Andersson , Anup Patel , Thierry Reding , Jonathan Hunter , jacob.jun.pan@linux.intel.com, Yury Norov , Andy Shevchenko , Rasmus Villemoes , Steven Rostedt , Petr Mladek , Sergey Senozhatsky , John Ogness , "Paul E. McKenney" , Frederic Weisbecker , quic_neeraju@quicinc.com, Josh Triplett , Mathieu Desnoyers , Lai Jiangshan , Joel Fernandes , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Ben Segall , Mel Gorman , Daniel Bristot de Oliveira , vschneid@redhat.com, jpoimboe@kernel.org, alpha , Linux Kernel Mailing List , "open list:SYNOPSYS ARC ARCHITECTURE" , Linux ARM , linux-omap , linux-csky@vger.kernel.org, "open list:QUALCOMM HEXAGON..." , "open list:IA64 (Itanium) PLATFORM" , linux-m68k , "open list:BROADCOM NVRAM DRIVER" , Openrisc , Parisc List , linuxppc-dev , linux-riscv , linux-s390 , Linux-sh list , sparclinux , linux-um , linux-perf-users@vger.kernel.org, "open list:DRM DRIVER FOR QEMU'S CIRRUS DEVICE" , xen-devel , "open list:TENSILICA XTENSA PORT (xtensa)" , ACPI Devel Maling List , Linux PM list , linux-clk , linux-arm-msm , "open list:TEGRA ARCHITECTURE SUPPORT" , linux-arch , rcu@vger.kernel.org Subject: Re: [PATCH 33/36] cpuidle,omap3: Use WFI for omap3_pm_idle() Message-ID: References: <20220608142723.103523089@infradead.org> <20220608144518.010587032@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-tegra@vger.kernel.org On Wed, Jun 08, 2022 at 06:28:33PM +0200, Arnd Bergmann wrote: > On Wed, Jun 8, 2022 at 4:27 PM Peter Zijlstra wrote: > > > > arch_cpu_idle() is a very simple idle interface and exposes only a > > single idle state and is expected to not require RCU and not do any > > tracing/instrumentation. > > > > As such, omap_sram_idle() is not a valid implementation. Replace it > > with the simple (shallow) omap3_do_wfi() call. Leaving the more > > complicated idle states for the cpuidle driver. > > > > Signed-off-by: Peter Zijlstra (Intel) > > I see similar code in omap2: > > omap2_pm_idle() > -> omap2_enter_full_retention() > -> omap2_sram_suspend() > > Is that code path safe to use without RCU or does it need a similar change? It needs a similar change, clearly I was running on fumes to not have found that when grepping around the omap code :/