, Arnd Bergmann <a...@arndb.de>, ulli.kr...@googlemail.com, vgu...@kernel.org, linux-...@vger.kernel.org, j...@joshtriplett.org, rost...@goodmis.org, r...@vger.kernel.org, b...@alien8.de, bc...@quicinc.com, tsbog...@alpha.franken.de, linux-par...@vger.kernel.org, sudeep.ho...@arm.com, shawn...@kernel.org, da...@davemloft.net, dal...@libc.org, t...@atomide.com, amakha...@vmware.com, bjorn.anders...@linaro.org, h...@zytor.com, sparcli...@vger.kernel.org, linux-hexa...@vger.kernel.org, linux-ri...@lists.infradead.org, anton.iva...@cambridgegreys.com, jo...@southpole.se, yury.no...@gmail.com, rich...@nod.at, x...@kernel.org, li...@armlinux.org.uk, mi...@redhat.com, a...@eecs.berkeley.edu, paul...@kernel.org, h...@linux.ibm.com, stefan.kristians...@saunalahti.fi, openr...@lists.librecores.org, paul.walms...@sifive.com, linux-te...@vger.kernel.org, namhy...@kernel.org, andriy.shevche...@linux.intel.com, jpoim...@kernel.org, jgr...@suse.com, mon...@monstr.eu, linux-m...@vger.kernel.org, palmer@dab belt.com, a...@brainfault.org, i...@jurassic.park.msu.ru, johan...@sipsolutions.net, linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+archive=mail-archive....@lists.ozlabs.org Sender: "Linuxppc-dev" <linuxppc-dev-bounces+archive=mail-archive....@lists.ozlabs.org>
Hi Peter, On Wed, 08 Jun 2022 16:27:27 +0200, Peter Zijlstra <pet...@infradead.org> 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) <pet...@infradead.org> > --- > 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? > + > -static __cpuidle int intel_idle(struct cpuidle_device *dev, > - struct cpuidle_driver *drv, int index) > +static __always_inline int __intel_idle(struct cpuidle_device *dev, > + struct cpuidle_driver *drv, int > index) { > struct cpuidle_state *state = &drv->states[index]; > unsigned long eax = flg2MWAIT(state->flags); > unsigned long ecx = 1; /* break on interrupt flag */ > > - if (state->flags & CPUIDLE_FLAG_IRQ_ENABLE) > - local_irq_enable(); > - > mwait_idle_with_hints(eax, ecx); > > return index; > } > > +static __cpuidle int intel_idle(struct cpuidle_device *dev, > + struct cpuidle_driver *drv, int index) > +{ > + return __intel_idle(dev, drv, index); > +} > + > +static __cpuidle int intel_idle_irq(struct cpuidle_device *dev, > + struct cpuidle_driver *drv, int > index) +{ > + int ret; > + > + raw_local_irq_enable(); > + ret = __intel_idle(dev, drv, index); > + raw_local_irq_disable(); > + > + return ret; > +} > + > /** > * intel_idle_s2idle - Ask the processor to enter the given idle state. > * @dev: cpuidle device of the target CPU. > @@ -1801,6 +1824,9 @@ static void __init intel_idle_init_cstat > /* Structure copy. */ > drv->states[drv->state_count] = > cpuidle_state_table[cstate]; > + if (cpuidle_state_table[cstate].flags & > CPUIDLE_FLAG_IRQ_ENABLE) > + drv->states[drv->state_count].enter = > intel_idle_irq; + > if ((disabled_states_mask & BIT(drv->state_count)) || > ((icpu->use_acpi || force_use_acpi) && > intel_idle_off_by_default(mwait_hint) && > > Thanks, Jacob