All of lore.kernel.org
 help / color / mirror / Atom feed
From: Daniel Lezcano <daniel.lezcano@linaro.org>
To: Chuansheng Liu <chuansheng.liu@intel.com>
Cc: lenb@kernel.org, len.brown@intel.com, linux-pm@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/3] intel_idle: Removing the redundant calculating for dev->state_count
Date: Sat, 09 Mar 2013 04:00:16 +0100	[thread overview]
Message-ID: <513AA5C0.2020604@linaro.org> (raw)
In-Reply-To: <1362755074.31506.45.camel@cliu38-desktop-build>

On 03/08/2013 04:04 PM, Chuansheng Liu wrote:
> 
> In function intel_idle_cpu_init() and intel_idle_cpuidle_driver_init(),
> they are having the same for(;;) loop.
> 
> Here in intel_idle_cpu_init(), the dev->state_count can be assigned by
> drv->state_count directly.
> 
> Signed-off-by: liu chuansheng <chuansheng.liu@intel.com>
> ---
>  drivers/idle/intel_idle.c |   30 ++----------------------------
>  1 files changed, 2 insertions(+), 28 deletions(-)
> 
> diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
> index 17c9cf9..503b401 100644
> --- a/drivers/idle/intel_idle.c
> +++ b/drivers/idle/intel_idle.c
> @@ -599,38 +599,12 @@ static int intel_idle_cpuidle_driver_init(void)
>   */
>  static int intel_idle_cpu_init(int cpu)
>  {
> -	int cstate;
>  	struct cpuidle_device *dev;
> +	struct cpuidle_driver *drv = &intel_idle_driver;
>  
>  	dev = per_cpu_ptr(intel_idle_cpuidle_devices, cpu);
>  
> -	dev->state_count = 1;
> -
> -	for (cstate = 0; cstate < CPUIDLE_STATE_MAX; ++cstate) {
> -		int num_substates, mwait_hint, mwait_cstate, mwait_substate;
> -
> -		if (cpuidle_state_table[cstate].enter == NULL)
> -			break;
> -
> -		if (cstate + 1 > max_cstate) {
> -			printk(PREFIX "max_cstate %d reached\n", max_cstate);
> -			break;
> -		}
> -
> -		mwait_hint = flg2MWAIT(cpuidle_state_table[cstate].flags);
> -		mwait_cstate = MWAIT_HINT2CSTATE(mwait_hint);
> -		mwait_substate = MWAIT_HINT2SUBSTATE(mwait_hint);
> -
> -		/* does the state exist in CPUID.MWAIT? */
> -		num_substates = (mwait_substates >> ((mwait_cstate + 1) * 4))
> -					& MWAIT_SUBSTATE_MASK;
> -
> -		/* if sub-state in table is not enumerated by CPUID */
> -		if ((mwait_substate + 1) > num_substates)
> -			continue;
> -
> -		dev->state_count += 1;
> -	}
> +	dev->state_count = drv->state_count;

The cpuidle_register_device function already does this initialization.

Probably you can get rid of this initialization and certainly factor out
a bit the code in this case.


-- 
 <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs

Follow Linaro:  <http://www.facebook.com/pages/Linaro> Facebook |
<http://twitter.com/#!/linaroorg> Twitter |
<http://www.linaro.org/linaro-blog/> Blog


  reply	other threads:[~2013-03-09  3:00 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-03-07 16:42 [PATCH] intel_idle: set the state_tables array into __initdata to save mem Chuansheng Liu
2013-03-07  9:49 ` Daniel Lezcano
2013-03-08  0:44   ` Liu, Chuansheng
2013-03-08  0:44     ` Liu, Chuansheng
2013-03-08 15:02 ` [PATCH 0/3] " Chuansheng Liu
2013-03-08 15:03   ` [PATCH 1/3] intel_idle: changing the continue to break in intel_idle_cpu_init() Chuansheng Liu
2013-03-09  3:01     ` Daniel Lezcano
2013-03-08 15:04   ` [PATCH 2/3] intel_idle: Removing the redundant calculating for dev->state_count Chuansheng Liu
2013-03-09  3:00     ` Daniel Lezcano [this message]
2013-03-11  1:29       ` Liu, Chuansheng
2013-03-11  1:29         ` Liu, Chuansheng
2013-03-11 10:44     ` [PATCH 2/3 V2] " Chuansheng Liu
2013-03-11  9:08       ` Daniel Lezcano
2013-03-08 15:06   ` [PATCH 3/3] intel_idle: set the state_tables array as __initdata to save mem Chuansheng Liu
2013-03-09  3:01     ` 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=513AA5C0.2020604@linaro.org \
    --to=daniel.lezcano@linaro.org \
    --cc=chuansheng.liu@intel.com \
    --cc=len.brown@intel.com \
    --cc=lenb@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pm@vger.kernel.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.