Re: [patch 2/3] Enable setting of IRQ-thread priorities from kernel cmdline (repost:CC to LKML)

[Randy Dunlap <randy.dunlap@oracle.com>]

On Wed, 19 Dec 2007 20:45:53 +0100 Remy Bohmer wrote:

>  Documentation/kernel-parameters.txt |    7 ++
>  include/linux/irq.h                 |    1 
>  kernel/irq/manage.c                 |  101 ++++++++++++++++++++++++++++++++----
>  3 files changed, 98 insertions(+), 11 deletions(-)
> 
> Index: linux-2.6.24-rc5-rt1/Documentation/kernel-parameters.txt
> ===================================================================
> --- linux-2.6.24-rc5-rt1.orig/Documentation/kernel-parameters.txt	2007-12-18 22:09:13.000000000 +0100
> +++ linux-2.6.24-rc5-rt1/Documentation/kernel-parameters.txt	2007-12-18 22:09:16.000000000 +0100
> @@ -799,6 +799,13 @@ and is between 256 and 4096 characters. 
>  	ips=		[HW,SCSI] Adaptec / IBM ServeRAID controller
>  			See header of drivers/scsi/ips.c.
>  
> +	irq_pmap=	[IRQ-threading] List of priorities each interrupt
> +			thread must have.
> +			Format: irq_pmap=megasas:90,eth0:40,50
> +			The first field without ':', is the default prio.

	Drop comma.

> +			If this cmdline argument is ommitted, every thread

                                                    omitted,

> +			runs at prio 50.
> +
>  	ports=		[IP_VS_FTP] IPVS ftp helper module
>  			Default is 21.
>  			Up to 8 (IP_VS_APP_MAX_PORTS) ports

> Index: linux-2.6.24-rc5-rt1/kernel/irq/manage.c
> ===================================================================
> --- linux-2.6.24-rc5-rt1.orig/kernel/irq/manage.c	2007-12-18 22:09:13.000000000 +0100
> +++ linux-2.6.24-rc5-rt1/kernel/irq/manage.c	2007-12-18 22:15:43.000000000 +0100

> @@ -901,3 +918,65 @@ void __init early_init_hardirqs(void)
>  	for (i = 0; i < NR_IRQS; i++)
>  		init_waitqueue_head(&irq_desc[i].wait_for_handler);
>  }
> +
> +#ifdef CONFIG_PREEMPT_HARDIRQS
> +
> +/*
> + * Lookup the interrupt thread priority
> + * A map for the priorities can be given on the kernel commandline.
> + * if name is NULL, or no kernel commandline options is given, the default

      If ...................................... option is given,

> + * prio is used, which is either MAX_PRIO/2, or the default given on the
> + * kernel commandline.
> + */
> +static int get_irq_prio(const char *name)
> +{


---
~Randy