All of lore.kernel.org
 help / color / mirror / Atom feed
From: jszhang@marvell.com (Jisheng Zhang)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 1/2] ARM: cpuidle: fix !cpuidle_ops[cpu].init case during init
Date: Wed, 30 Mar 2016 15:16:29 +0800	[thread overview]
Message-ID: <20160330151629.0b338365@xhacker> (raw)
In-Reply-To: <56F52502.3060308@linaro.org>

Hi Daniel,

On Fri, 25 Mar 2016 12:46:10 +0100 Daniel Lezcano wrote:

> On 03/24/2016 06:11 AM, Jisheng Zhang wrote:
> > Let's assume cpuidle_ops exists but it doesn't implement the according
> > init member, current arm_cpuidle_init() will return success to its
> > caller, but in fact it should return -EOPNOTSUPP.
> >
> > Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
> > ---
> >   arch/arm/kernel/cpuidle.c | 8 ++++++--
> >   1 file changed, 6 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/arm/kernel/cpuidle.c b/arch/arm/kernel/cpuidle.c
> > index 703926e..f108d8f 100644
> > --- a/arch/arm/kernel/cpuidle.c
> > +++ b/arch/arm/kernel/cpuidle.c
> > @@ -143,8 +143,12 @@ int __init arm_cpuidle_init(int cpu)
> >   		return -ENODEV;
> >
> >   	ret = arm_cpuidle_read_ops(cpu_node, cpu);
> > -	if (!ret && cpuidle_ops[cpu].init)
> > -		ret = cpuidle_ops[cpu].init(cpu_node, cpu);
> > +	if (!ret) {
> > +		if (cpuidle_ops[cpu].init)
> > +			ret = cpuidle_ops[cpu].init(cpu_node, cpu);
> > +		else
> > +			ret = -EOPNOTSUPP;
> > +	}  
> 
> Hi Jisheng,
> 
> this should be handled in the arm_cpuidle_read_ops function.
> 

Thanks for reviewing. After some consideration, I think this patch isn't correct
There may be platforms which doesn't need the init member at all, although
currently I don't see such platforms in mainline, So I'll drop this patch
and send out one v2 only does the optimization.

Thanks a lot,
Jisheng

WARNING: multiple messages have this Message-ID (diff)
From: Jisheng Zhang <jszhang@marvell.com>
To: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: <linux@arm.linux.org.uk>, <linux-arm-kernel@lists.infradead.org>,
	<linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/2] ARM: cpuidle: fix !cpuidle_ops[cpu].init case during init
Date: Wed, 30 Mar 2016 15:16:29 +0800	[thread overview]
Message-ID: <20160330151629.0b338365@xhacker> (raw)
In-Reply-To: <56F52502.3060308@linaro.org>

Hi Daniel,

On Fri, 25 Mar 2016 12:46:10 +0100 Daniel Lezcano wrote:

> On 03/24/2016 06:11 AM, Jisheng Zhang wrote:
> > Let's assume cpuidle_ops exists but it doesn't implement the according
> > init member, current arm_cpuidle_init() will return success to its
> > caller, but in fact it should return -EOPNOTSUPP.
> >
> > Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
> > ---
> >   arch/arm/kernel/cpuidle.c | 8 ++++++--
> >   1 file changed, 6 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/arm/kernel/cpuidle.c b/arch/arm/kernel/cpuidle.c
> > index 703926e..f108d8f 100644
> > --- a/arch/arm/kernel/cpuidle.c
> > +++ b/arch/arm/kernel/cpuidle.c
> > @@ -143,8 +143,12 @@ int __init arm_cpuidle_init(int cpu)
> >   		return -ENODEV;
> >
> >   	ret = arm_cpuidle_read_ops(cpu_node, cpu);
> > -	if (!ret && cpuidle_ops[cpu].init)
> > -		ret = cpuidle_ops[cpu].init(cpu_node, cpu);
> > +	if (!ret) {
> > +		if (cpuidle_ops[cpu].init)
> > +			ret = cpuidle_ops[cpu].init(cpu_node, cpu);
> > +		else
> > +			ret = -EOPNOTSUPP;
> > +	}  
> 
> Hi Jisheng,
> 
> this should be handled in the arm_cpuidle_read_ops function.
> 

Thanks for reviewing. After some consideration, I think this patch isn't correct
There may be platforms which doesn't need the init member at all, although
currently I don't see such platforms in mainline, So I'll drop this patch
and send out one v2 only does the optimization.

Thanks a lot,
Jisheng

  reply	other threads:[~2016-03-30  7:16 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-03-24  5:11 [PATCH 0/2] ARM: cpuidle: bug fix and a trivial improvement Jisheng Zhang
2016-03-24  5:11 ` Jisheng Zhang
2016-03-24  5:11 ` [PATCH 1/2] ARM: cpuidle: fix !cpuidle_ops[cpu].init case during init Jisheng Zhang
2016-03-24  5:11   ` Jisheng Zhang
2016-03-25 11:46   ` Daniel Lezcano
2016-03-25 11:46     ` Daniel Lezcano
2016-03-30  7:16     ` Jisheng Zhang [this message]
2016-03-30  7:16       ` Jisheng Zhang
2016-03-30  8:09       ` Daniel Lezcano
2016-03-30  8:09         ` Daniel Lezcano
2016-03-30  8:17         ` Jisheng Zhang
2016-03-30  8:17           ` Jisheng Zhang
2016-03-30  8:41           ` Daniel Lezcano
2016-03-30  8:41             ` Daniel Lezcano
2016-03-30  8:43             ` Jisheng Zhang
2016-03-30  8:43               ` Jisheng Zhang
2016-03-30  9:31               ` Daniel Lezcano
2016-03-30  9:31                 ` Daniel Lezcano
2016-03-30  9:42                 ` Jisheng Zhang
2016-03-30  9:42                   ` Jisheng Zhang
2016-03-30 10:36         ` Lorenzo Pieralisi
2016-03-30 10:36           ` Lorenzo Pieralisi
2016-03-24  5:11 ` [PATCH 2/2] ARM: cpuidle: make arm_cpuidle_suspend() a bit more efficient Jisheng Zhang
2016-03-24  5:11   ` Jisheng Zhang
2016-03-25 11:52   ` Daniel Lezcano
2016-03-25 11:52     ` Daniel Lezcano

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20160330151629.0b338365@xhacker \
    --to=jszhang@marvell.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.