diff mbox series

[33/36] cpuidle,omap3: Use WFI for omap3_pm_idle()

Message ID 20220608144518.010587032@infradead.org
State New
Headers show
Series cpuidle,rcu: Cleanup the mess | expand

Commit Message

Peter Zijlstra June 8, 2022, 2:27 p.m. UTC
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@infradead.org>
---
 arch/arm/mach-omap2/pm34xx.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Peter Zijlstra June 9, 2022, 9:40 a.m. UTC | #1
On Wed, Jun 08, 2022 at 06:28:33PM +0200, Arnd Bergmann wrote:
> On Wed, Jun 8, 2022 at 4:27 PM Peter Zijlstra <peterz@infradead.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@infradead.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?

It needs a similar change, clearly I was running on fumes to not have
found that when grepping around the omap code :/
Tony Lindgren June 13, 2022, 12:36 p.m. UTC | #2
* Peter Zijlstra <peterz@infradead.org> [220608 14:52]:
> 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.

Acked-by: Tony Lindgren <tony@atomide.com>
diff mbox series

Patch

--- a/arch/arm/mach-omap2/pm34xx.c
+++ b/arch/arm/mach-omap2/pm34xx.c
@@ -294,7 +294,7 @@  static void omap3_pm_idle(void)
 	if (omap_irq_pending())
 		return;
 
-	omap_sram_idle();
+	omap3_do_wfi();
 }
 
 #ifdef CONFIG_SUSPEND