| Message ID | 20170613130557.26315-10-npiggin@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
Nicholas Piggin <npiggin@gmail.com> writes: > local_irq_enable can cause interrupts to be taken which could > take significant amount of processing time. The idle process > should set its polling flag before this, so another process that > wakes it during this time will not have to send an IPI. > > Expand the TIF_POLLING_NRFLAG coverage to as large as possible. > > Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> > Signed-off-by: Nicholas Piggin <npiggin@gmail.com> > --- > drivers/cpuidle/cpuidle-powernv.c | 4 +++- > drivers/cpuidle/cpuidle-pseries.c | 3 ++- > 2 files changed, 5 insertions(+), 2 deletions(-) I don't think the cpuidle folks are really interested in these changes, but we should Cc them to be polite. Can you resend patches 9, 10, 11 with a subject like: "cpuidle: powernv: Set polling ..." And Cc the cpuidle folks: $ ./scripts/get_maintainer.pl -f drivers/cpuidle rjw@rjwysocki.net daniel.lezcano@linaro.org linux-pm@vger.kernel.org linux-kernel@vger.kernel.org cheers
On Wed, 14 Jun 2017 21:40:52 +1000 Michael Ellerman <mpe@ellerman.id.au> wrote: > Nicholas Piggin <npiggin@gmail.com> writes: > > > local_irq_enable can cause interrupts to be taken which could > > take significant amount of processing time. The idle process > > should set its polling flag before this, so another process that > > wakes it during this time will not have to send an IPI. > > > > Expand the TIF_POLLING_NRFLAG coverage to as large as possible. > > > > Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> > > Signed-off-by: Nicholas Piggin <npiggin@gmail.com> > > --- > > drivers/cpuidle/cpuidle-powernv.c | 4 +++- > > drivers/cpuidle/cpuidle-pseries.c | 3 ++- > > 2 files changed, 5 insertions(+), 2 deletions(-) > > I don't think the cpuidle folks are really interested in these changes, > but we should Cc them to be polite. > > Can you resend patches 9, 10, 11 with a subject like: > > "cpuidle: powernv: Set polling ..." > > And Cc the cpuidle folks: > > $ ./scripts/get_maintainer.pl -f drivers/cpuidle > rjw@rjwysocki.net > daniel.lezcano@linaro.org > linux-pm@vger.kernel.org > linux-kernel@vger.kernel.org Yeah I can do that. I'll send them as thier own series. They don't depend on any of the patches in this series, so I should have done that in the first place. Thanks, Nick
Nicholas Piggin <npiggin@gmail.com> writes: > On Wed, 14 Jun 2017 21:40:52 +1000 > Michael Ellerman <mpe@ellerman.id.au> wrote: > >> Nicholas Piggin <npiggin@gmail.com> writes: >> >> > local_irq_enable can cause interrupts to be taken which could >> > take significant amount of processing time. The idle process >> > should set its polling flag before this, so another process that >> > wakes it during this time will not have to send an IPI. >> > >> > Expand the TIF_POLLING_NRFLAG coverage to as large as possible. >> > >> > Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> >> > Signed-off-by: Nicholas Piggin <npiggin@gmail.com> >> > --- >> > drivers/cpuidle/cpuidle-powernv.c | 4 +++- >> > drivers/cpuidle/cpuidle-pseries.c | 3 ++- >> > 2 files changed, 5 insertions(+), 2 deletions(-) >> >> I don't think the cpuidle folks are really interested in these changes, >> but we should Cc them to be polite. >> >> Can you resend patches 9, 10, 11 with a subject like: >> >> "cpuidle: powernv: Set polling ..." >> >> And Cc the cpuidle folks: >> >> $ ./scripts/get_maintainer.pl -f drivers/cpuidle >> rjw@rjwysocki.net >> daniel.lezcano@linaro.org >> linux-pm@vger.kernel.org >> linux-kernel@vger.kernel.org > > Yeah I can do that. I'll send them as thier own series. They don't > depend on any of the patches in this series, so I should have done > that in the first place. Great thanks. cheers
diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c index 79152676f62b..50b3c2e0306f 100644 --- a/drivers/cpuidle/cpuidle-powernv.c +++ b/drivers/cpuidle/cpuidle-powernv.c @@ -51,9 +51,10 @@ static int snooze_loop(struct cpuidle_device *dev, { u64 snooze_exit_time; - local_irq_enable(); set_thread_flag(TIF_POLLING_NRFLAG); + local_irq_enable(); + snooze_exit_time = get_tb() + snooze_timeout; ppc64_runlatch_off(); HMT_very_low(); @@ -66,6 +67,7 @@ static int snooze_loop(struct cpuidle_device *dev, ppc64_runlatch_on(); clear_thread_flag(TIF_POLLING_NRFLAG); smp_mb(); + return index; } diff --git a/drivers/cpuidle/cpuidle-pseries.c b/drivers/cpuidle/cpuidle-pseries.c index 166ccd711ec9..7b12bb2ea70f 100644 --- a/drivers/cpuidle/cpuidle-pseries.c +++ b/drivers/cpuidle/cpuidle-pseries.c @@ -62,9 +62,10 @@ static int snooze_loop(struct cpuidle_device *dev, unsigned long in_purr; u64 snooze_exit_time; + set_thread_flag(TIF_POLLING_NRFLAG); + idle_loop_prolog(&in_purr); local_irq_enable(); - set_thread_flag(TIF_POLLING_NRFLAG); snooze_exit_time = get_tb() + snooze_timeout; while (!need_resched()) {