Re: [patch 31/34] tile: Use generic idle loop

["Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>]

On 03/22/2013 03:23 AM, Thomas Gleixner wrote:
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Cc: Chris Metcalf <cmetcalf@tilera.com>
> ---
>  arch/tile/kernel/process.c |   61 ++++-----------------------------------------
>  arch/tile/kernel/smpboot.c |    2 -
>  2 files changed, 7 insertions(+), 56 deletions(-)
> 
> Index: linux-2.6/arch/tile/kernel/process.c
> ===================================================================
> --- linux-2.6.orig/arch/tile/kernel/process.c
> +++ linux-2.6/arch/tile/kernel/process.c
> @@ -40,13 +40,11 @@
>  #include <arch/abi.h>
>  #include <arch/sim_def.h>
> 
> -
>  /*
>   * Use the (x86) "idle=poll" option to prefer low latency when leaving the
>   * idle loop over low power while in the idle loop, e.g. if we have
>   * one thread per core and we want to get threads out of futex waits fast.
>   */
> -static int no_idle_nap;
>  static int __init idle_setup(char *str)
>  {
>  	if (!str)
> @@ -54,64 +52,17 @@ static int __init idle_setup(char *str)
> 
>  	if (!strcmp(str, "poll")) {
>  		pr_info("using polling idle threads.\n");
> -		no_idle_nap = 1;
> +		cpu_idle_poll_ctrl(true);
>  	} else if (!strcmp(str, "halt"))
> -		no_idle_nap = 0;
> -	else
> -		return -1;
> -
> -	return 0;
> +		return 0;
> +	return -1;
>  }
>  early_param("idle", idle_setup);
>

That doesn't look quite right, since it returns -1 (instead of 0) when
str == poll.

Regards,
Srivatsa S. Bhat