| Message ID | 1467785755-3488-3-git-send-email-jszhang@marvell.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Jul 06, 2016 at 02:15:55PM +0800, Jisheng Zhang wrote: > Currently, we check cpuidle_ops.suspend every time when entering a > low-power idle state. But this check could be avoided in this hot path > by moving it into arm_cpuidle_read_ops() to reduce arm_cpuidle_suspend > overhead a bit. > > Signed-off-by: Jisheng Zhang <jszhang@marvell.com> > --- Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Dear Daniel, On Thu, 7 Jul 2016 15:46:28 +0200 Daniel Lezcano wrote: > On Wed, Jul 06, 2016 at 02:15:55PM +0800, Jisheng Zhang wrote: > > Currently, we check cpuidle_ops.suspend every time when entering a > > low-power idle state. But this check could be avoided in this hot path > > by moving it into arm_cpuidle_read_ops() to reduce arm_cpuidle_suspend > > overhead a bit. > > > > Signed-off-by: Jisheng Zhang <jszhang@marvell.com> > > --- > > Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> I'm not sure the upstream merging path this patch should follow, Per my understanding, I need to put it into Russell's PATCH system. Thanks in advance, Jisheng
On Fri, Jul 08, 2016 at 02:17:29PM +0800, Jisheng Zhang wrote: > Dear Daniel, > > On Thu, 7 Jul 2016 15:46:28 +0200 Daniel Lezcano wrote: > > > On Wed, Jul 06, 2016 at 02:15:55PM +0800, Jisheng Zhang wrote: > > > Currently, we check cpuidle_ops.suspend every time when entering a > > > low-power idle state. But this check could be avoided in this hot path > > > by moving it into arm_cpuidle_read_ops() to reduce arm_cpuidle_suspend > > > overhead a bit. > > > > > > Signed-off-by: Jisheng Zhang <jszhang@marvell.com> > > > --- > > > > Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> > > I'm not sure the upstream merging path this patch should follow, Per my > understanding, I need to put it into Russell's PATCH system. Or alternatively through arm-soc -- Daniel
On Fri, 8 Jul 2016 12:50:12 +0200 Daniel Lezcano wrote: > On Fri, Jul 08, 2016 at 02:17:29PM +0800, Jisheng Zhang wrote: > > Dear Daniel, > > > > On Thu, 7 Jul 2016 15:46:28 +0200 Daniel Lezcano wrote: > > > > > On Wed, Jul 06, 2016 at 02:15:55PM +0800, Jisheng Zhang wrote: > > > > Currently, we check cpuidle_ops.suspend every time when entering a > > > > low-power idle state. But this check could be avoided in this hot path > > > > by moving it into arm_cpuidle_read_ops() to reduce arm_cpuidle_suspend > > > > overhead a bit. > > > > > > > > Signed-off-by: Jisheng Zhang <jszhang@marvell.com> > > > > --- > > > > > > Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> > > > > I'm not sure the upstream merging path this patch should follow, Per my > > understanding, I need to put it into Russell's PATCH system. > > Or alternatively through arm-soc > Got it. thanks. Dear Arnd, Olof, I have no pull request permission. what's your preference? Could you please advise? Thanks
On Fri, Jul 08, 2016 at 06:58:54PM +0800, Jisheng Zhang wrote: > On Fri, 8 Jul 2016 12:50:12 +0200 Daniel Lezcano wrote: > > > On Fri, Jul 08, 2016 at 02:17:29PM +0800, Jisheng Zhang wrote: > > > Dear Daniel, > > > > > > On Thu, 7 Jul 2016 15:46:28 +0200 Daniel Lezcano wrote: > > > > > > > On Wed, Jul 06, 2016 at 02:15:55PM +0800, Jisheng Zhang wrote: > > > > > Currently, we check cpuidle_ops.suspend every time when entering a > > > > > low-power idle state. But this check could be avoided in this hot path > > > > > by moving it into arm_cpuidle_read_ops() to reduce arm_cpuidle_suspend > > > > > overhead a bit. > > > > > > > > > > Signed-off-by: Jisheng Zhang <jszhang@marvell.com> > > > > > --- > > > > > > > > Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> > > > > > > I'm not sure the upstream merging path this patch should follow, Per my > > > understanding, I need to put it into Russell's PATCH system. > > > > Or alternatively through arm-soc > > > > Got it. thanks. > > Dear Arnd, Olof, > > I have no pull request permission. what's your preference? Could you please > advise? ... and because arm-soc people haven't responded, they've now ended up in the patch system... So I've applied them to my tree in a separate branch. Thanks!
On Thu, 14 Jul 2016 16:31:13 +0100 Russell King - ARM Linux wrote: > On Fri, Jul 08, 2016 at 06:58:54PM +0800, Jisheng Zhang wrote: > > On Fri, 8 Jul 2016 12:50:12 +0200 Daniel Lezcano wrote: > > > > > On Fri, Jul 08, 2016 at 02:17:29PM +0800, Jisheng Zhang wrote: > > > > Dear Daniel, > > > > > > > > On Thu, 7 Jul 2016 15:46:28 +0200 Daniel Lezcano wrote: > > > > > > > > > On Wed, Jul 06, 2016 at 02:15:55PM +0800, Jisheng Zhang wrote: > > > > > > Currently, we check cpuidle_ops.suspend every time when entering a > > > > > > low-power idle state. But this check could be avoided in this hot path > > > > > > by moving it into arm_cpuidle_read_ops() to reduce arm_cpuidle_suspend > > > > > > overhead a bit. > > > > > > > > > > > > Signed-off-by: Jisheng Zhang <jszhang@marvell.com> > > > > > > --- > > > > > > > > > > Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> > > > > > > > > I'm not sure the upstream merging path this patch should follow, Per my > > > > understanding, I need to put it into Russell's PATCH system. > > > > > > Or alternatively through arm-soc > > > > > > > Got it. thanks. > > > > Dear Arnd, Olof, > > > > I have no pull request permission. what's your preference? Could you please > > advise? > > ... and because arm-soc people haven't responded, they've now ended up > in the patch system... So I've applied them to my tree in a separate > branch. > Thank you so much!
diff --git a/arch/arm/kernel/cpuidle.c b/arch/arm/kernel/cpuidle.c index 2129b29..7dccc96 100644 --- a/arch/arm/kernel/cpuidle.c +++ b/arch/arm/kernel/cpuidle.c @@ -47,18 +47,13 @@ int arm_cpuidle_simple_enter(struct cpuidle_device *dev, * This function calls the underlying arch specific low level PM code as * registered at the init time. * - * Returns -EOPNOTSUPP if no suspend callback is defined, the result of the - * callback otherwise. + * Returns the result of the suspend callback. */ int arm_cpuidle_suspend(int index) { - int ret = -EOPNOTSUPP; int cpu = smp_processor_id(); - if (cpuidle_ops[cpu].suspend) - ret = cpuidle_ops[cpu].suspend(index); - - return ret; + return cpuidle_ops[cpu].suspend(index); } /** @@ -92,8 +87,8 @@ static const struct cpuidle_ops *__init arm_cpuidle_get_ops(const char *method) * process. * * Return 0 on sucess, -ENOENT if no 'enable-method' is defined, -EOPNOTSUPP if - * no cpuidle_ops is registered for the 'enable-method', or if no init callback - * is defined. + * no cpuidle_ops is registered for the 'enable-method', or if either init or + * suspend callback isn't defined. */ static int __init arm_cpuidle_read_ops(struct device_node *dn, int cpu) { @@ -111,8 +106,8 @@ static int __init arm_cpuidle_read_ops(struct device_node *dn, int cpu) return -EOPNOTSUPP; } - if (!ops->init) { - pr_warn("cpuidle_ops '%s': no init callback\n", + if (!ops->init || !ops->suspend) { + pr_warn("cpuidle_ops '%s': no init or suspend callback\n", enable_method); return -EOPNOTSUPP; }
Currently, we check cpuidle_ops.suspend every time when entering a low-power idle state. But this check could be avoided in this hot path by moving it into arm_cpuidle_read_ops() to reduce arm_cpuidle_suspend overhead a bit. Signed-off-by: Jisheng Zhang <jszhang@marvell.com> --- arch/arm/kernel/cpuidle.c | 17 ++++++----------- 1 file changed, 6 insertions(+), 11 deletions(-)