[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <CAK8P3a0g-fNu9=BUECSXcNeWT7XWHQMnSXZE-XYE+5eakHxKxA@mail.gmail.com>
Date: Wed, 8 Jun 2022 18:28:33 +0200
From: Arnd Bergmann <arnd@...db.de>
To: Peter Zijlstra <peterz@...radead.org>
Cc: Richard Henderson <rth@...ddle.net>,
Ivan Kokshaysky <ink@...assic.park.msu.ru>,
Matt Turner <mattst88@...il.com>,
Vineet Gupta <vgupta@...nel.org>,
Russell King - ARM Linux <linux@...linux.org.uk>,
Hans Ulli Kroll <ulli.kroll@...glemail.com>,
Linus Walleij <linus.walleij@...aro.org>,
Shawn Guo <shawnguo@...nel.org>,
Sascha Hauer <s.hauer@...gutronix.de>,
Sascha Hauer <kernel@...gutronix.de>,
Fabio Estevam <festevam@...il.com>,
NXP Linux Team <linux-imx@....com>,
Tony Lindgren <tony@...mide.com>,
Kevin Hilman <khilman@...nel.org>,
Catalin Marinas <catalin.marinas@....com>,
Will Deacon <will@...nel.org>, Guo Ren <guoren@...nel.org>,
bcain@...cinc.com, Huacai Chen <chenhuacai@...nel.org>,
Xuerui Wang <kernel@...0n.name>,
Geert Uytterhoeven <geert@...ux-m68k.org>,
Sam Creasey <sammy@...my.net>, Michal Simek <monstr@...str.eu>,
Thomas Bogendoerfer <tsbogend@...ha.franken.de>,
Dinh Nguyen <dinguyen@...nel.org>,
Jonas Bonn <jonas@...thpole.se>,
Stefan Kristiansson <stefan.kristiansson@...nalahti.fi>,
Stafford Horne <shorne@...il.com>,
James Bottomley <James.Bottomley@...senpartnership.com>,
Helge Deller <deller@....de>,
Michael Ellerman <mpe@...erman.id.au>,
Benjamin Herrenschmidt <benh@...nel.crashing.org>,
Paul Mackerras <paulus@...ba.org>,
Paul Walmsley <paul.walmsley@...ive.com>,
Palmer Dabbelt <palmer@...belt.com>,
Albert Ou <aou@...s.berkeley.edu>,
Heiko Carstens <hca@...ux.ibm.com>,
Vasily Gorbik <gor@...ux.ibm.com>,
Alexander Gordeev <agordeev@...ux.ibm.com>,
Christian Borntraeger <borntraeger@...ux.ibm.com>,
Sven Schnelle <svens@...ux.ibm.com>,
Yoshinori Sato <ysato@...rs.sourceforge.jp>,
Rich Felker <dalias@...c.org>,
David Miller <davem@...emloft.net>,
Richard Weinberger <richard@....at>,
Anton Ivanov <anton.ivanov@...bridgegreys.com>,
Johannes Berg <johannes@...solutions.net>,
Thomas Gleixner <tglx@...utronix.de>,
Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
Dave Hansen <dave.hansen@...ux.intel.com>,
"the arch/x86 maintainers" <x86@...nel.org>,
"H. Peter Anvin" <hpa@...or.com>,
Arnaldo Carvalho de Melo <acme@...nel.org>,
Mark Rutland <mark.rutland@....com>,
Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
Jiri Olsa <jolsa@...nel.org>,
Namhyung Kim <namhyung@...nel.org>,
Juergen Gross <jgross@...e.com>, srivatsa@...il.mit.edu,
amakhalov@...are.com, Pv-drivers <pv-drivers@...are.com>,
Boris Ostrovsky <boris.ostrovsky@...cle.com>,
Chris Zankel <chris@...kel.net>,
Max Filippov <jcmvbkbc@...il.com>,
Rafael Wysocki <rafael@...nel.org>,
Len Brown <lenb@...nel.org>, Pavel Machek <pavel@....cz>,
gregkh <gregkh@...uxfoundation.org>,
Michael Turquette <mturquette@...libre.com>,
Stephen Boyd <sboyd@...nel.org>,
Daniel Lezcano <daniel.lezcano@...aro.org>,
lpieralisi@...nel.org, Sudeep Holla <sudeep.holla@....com>,
Andy Gross <agross@...nel.org>,
Bjorn Andersson <bjorn.andersson@...aro.org>,
Anup Patel <anup@...infault.org>,
Thierry Reding <thierry.reding@...il.com>,
Jonathan Hunter <jonathanh@...dia.com>,
jacob.jun.pan@...ux.intel.com, Arnd Bergmann <arnd@...db.de>,
Yury Norov <yury.norov@...il.com>,
Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
Rasmus Villemoes <linux@...musvillemoes.dk>,
Steven Rostedt <rostedt@...dmis.org>,
Petr Mladek <pmladek@...e.com>,
Sergey Senozhatsky <senozhatsky@...omium.org>,
John Ogness <john.ogness@...utronix.de>,
"Paul E. McKenney" <paulmck@...nel.org>,
Frederic Weisbecker <frederic@...nel.org>,
quic_neeraju@...cinc.com, Josh Triplett <josh@...htriplett.org>,
Mathieu Desnoyers <mathieu.desnoyers@...icios.com>,
Lai Jiangshan <jiangshanlai@...il.com>,
Joel Fernandes <joel@...lfernandes.org>,
Juri Lelli <juri.lelli@...hat.com>,
Vincent Guittot <vincent.guittot@...aro.org>,
Dietmar Eggemann <dietmar.eggemann@....com>,
Ben Segall <bsegall@...gle.com>, Mel Gorman <mgorman@...e.de>,
Daniel Bristot de Oliveira <bristot@...hat.com>,
vschneid@...hat.com, jpoimboe@...nel.org,
alpha <linux-alpha@...r.kernel.org>,
Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
"open list:SYNOPSYS ARC ARCHITECTURE"
<linux-snps-arc@...ts.infradead.org>,
Linux ARM <linux-arm-kernel@...ts.infradead.org>,
linux-omap <linux-omap@...r.kernel.org>,
linux-csky@...r.kernel.org,
"open list:QUALCOMM HEXAGON..." <linux-hexagon@...r.kernel.org>,
"open list:IA64 (Itanium) PLATFORM" <linux-ia64@...r.kernel.org>,
linux-m68k <linux-m68k@...ts.linux-m68k.org>,
"open list:BROADCOM NVRAM DRIVER" <linux-mips@...r.kernel.org>,
Openrisc <openrisc@...ts.librecores.org>,
Parisc List <linux-parisc@...r.kernel.org>,
linuxppc-dev <linuxppc-dev@...ts.ozlabs.org>,
linux-riscv <linux-riscv@...ts.infradead.org>,
linux-s390 <linux-s390@...r.kernel.org>,
Linux-sh list <linux-sh@...r.kernel.org>,
sparclinux <sparclinux@...r.kernel.org>,
linux-um <linux-um@...ts.infradead.org>,
linux-perf-users@...r.kernel.org,
"open list:DRM DRIVER FOR QEMU'S CIRRUS DEVICE"
<virtualization@...ts.linux-foundation.org>,
xen-devel <xen-devel@...ts.xenproject.org>,
"open list:TENSILICA XTENSA PORT (xtensa)"
<linux-xtensa@...ux-xtensa.org>,
ACPI Devel Maling List <linux-acpi@...r.kernel.org>,
Linux PM list <linux-pm@...r.kernel.org>,
linux-clk <linux-clk@...r.kernel.org>,
linux-arm-msm <linux-arm-msm@...r.kernel.org>,
"open list:TEGRA ARCHITECTURE SUPPORT" <linux-tegra@...r.kernel.org>,
linux-arch <linux-arch@...r.kernel.org>, rcu@...r.kernel.org
Subject: Re: [PATCH 33/36] cpuidle,omap3: Use WFI for omap3_pm_idle()
On Wed, Jun 8, 2022 at 4:27 PM Peter Zijlstra <peterz@...radead.org> 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) <peterz@...radead.org>
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?
Arnd
Powered by blists - more mailing lists