[PATCH] ACPI: Kill overly verbose "power state" log messages

[PATCH] ACPI: Kill overly verbose "power state" log messages

[Roland Dreier]

I was recently lucky enough to get a 64-CPU system.  The processors
actually have T-states, so my kernel log ends up with 64 lines like:

    ACPI: CPU0 (power states: C1[C1] C2[C3])

This is pretty useless clutter because this info is already available
after boot from both /sys/devices/system/cpu/cpu*/cpuidle/state?/ as
well as /proc/acpi/processor/CPU*/power.

So just delete the code that prints the throttling states in
processor_idle.c.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
---
 drivers/acpi/processor_idle.c |    7 -------
 1 files changed, 0 insertions(+), 7 deletions(-)

diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index cc61a62..706eacf 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -1214,13 +1214,6 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
 		acpi_processor_setup_cpuidle(pr);
 		if (cpuidle_register_device(&pr->power.dev))
 			return -EIO;
-
-		printk(KERN_INFO PREFIX "CPU%d (power states:", pr->id);
-		for (i = 1; i <= pr->power.count; i++)
-			if (pr->power.states[i].valid)
-				printk(" C%d[C%d]", i,
-				       pr->power.states[i].type);
-		printk(")\n");
 	}
 #ifdef CONFIG_ACPI_PROCFS
 	/* 'power' [R] */

Re: [PATCH] ACPI: Kill overly verbose "power state" log messages

[ykzhao]

On Fri, 2009-09-25 at 05:52 +0800, Roland Dreier wrote:
> I was recently lucky enough to get a 64-CPU system.  The processors
> actually have T-states, so my kernel log ends up with 64 lines like:
> 
>     ACPI: CPU0 (power states: C1[C1] C2[C3])
> 
> This is pretty useless clutter because this info is already available
> after boot from both /sys/devices/system/cpu/cpu*/cpuidle/state?/ as
> well as /proc/acpi/processor/CPU*/power.
> 
> So just delete the code that prints the throttling states in
> processor_idle.c.
It seems that it is unnecessary to delete the C-state info.
Thanks.
> 
> Signed-off-by: Roland Dreier <rolandd@cisco.com>
> ---
>  drivers/acpi/processor_idle.c |    7 -------
>  1 files changed, 0 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
> index cc61a62..706eacf 100644
> --- a/drivers/acpi/processor_idle.c
> +++ b/drivers/acpi/processor_idle.c
> @@ -1214,13 +1214,6 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
>  		acpi_processor_setup_cpuidle(pr);
>  		if (cpuidle_register_device(&pr->power.dev))
>  			return -EIO;
> -
> -		printk(KERN_INFO PREFIX "CPU%d (power states:", pr->id);
> -		for (i = 1; i <= pr->power.count; i++)
> -			if (pr->power.states[i].valid)
> -				printk(" C%d[C%d]", i,
> -				       pr->power.states[i].type);
> -		printk(")\n");
>  	}
>  #ifdef CONFIG_ACPI_PROCFS
>  	/* 'power' [R] */
> --
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Re: [PATCH] ACPI: Kill overly verbose "power state" log messages

[Roland Dreier]

Len, I see I messed up editing my changelog message, see below...

 > > I was recently lucky enough to get a 64-CPU system.  The processors
 > > actually have T-states, so my kernel log ends up with 64 lines like:
 > > 
 > >     ACPI: CPU0 (power states: C1[C1] C2[C3])
 > > 
 > > This is pretty useless clutter because this info is already available
 > > after boot from both /sys/devices/system/cpu/cpu*/cpuidle/state?/ as
 > > well as /proc/acpi/processor/CPU*/power.
 > > 
 > > So just delete the code that prints the throttling states in
 > > processor_idle.c.

 > It seems that it is unnecessary to delete the C-state info.

Sorry, this is a little too terse for me to know what you mean.
Certainly it's not useful to have 64 copies of

    ACPI: CPU0 (power states: C1[C1] C2[C3])

in the kernel log on a big box, when all 64 processors are going to
support the same C-states.  However, I don't see what the use of having
even one copy in the boot log is, when I can easily get that info at
runtime from /proc/acpi/processor/CPU*/power.


Anyway, Len, I see I copy-and-pasted too quickly from my T-state patch
submission... if you want to apply, a version with better changelog would be:

<--- snip --->

I was recently lucky enough to get a 64-CPU system, so my kernel log
ends up with 64 lines like:

    ACPI: CPU0 (power states: C1[C1] C2[C3])

This is pretty useless clutter because this info is already available
after boot from both /sys/devices/system/cpu/cpu*/cpuidle/state?/ as
well as /proc/acpi/processor/CPU*/power.

So just delete the code that prints the C-states in processor_idle.c.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
---
 drivers/acpi/processor_idle.c |    7 -------
 1 files changed, 0 insertions(+), 7 deletions(-)

diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index cc61a62..706eacf 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -1214,13 +1214,6 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
 		acpi_processor_setup_cpuidle(pr);
 		if (cpuidle_register_device(&pr->power.dev))
 			return -EIO;
-
-		printk(KERN_INFO PREFIX "CPU%d (power states:", pr->id);
-		for (i = 1; i <= pr->power.count; i++)
-			if (pr->power.states[i].valid)
-				printk(" C%d[C%d]", i,
-				       pr->power.states[i].type);
-		printk(")\n");
 	}
 #ifdef CONFIG_ACPI_PROCFS
 	/* 'power' [R] */

Re: [PATCH] ACPI: Kill overly verbose "power state" log messages

[Len Brown]

> So just delete the code that prints the C-states in processor_idle.c.

applied

thanks,
Len Brown, Intel Open Source Technology Center