[PATCH 3/4] dma-debug: add dma_debug_driver kernel command line

Andrew Morton akpm at linux-foundation.org
Mon Jun 1 15:08:13 PDT 2009


On Thu, 28 May 2009 17:19:30 +0200
Joerg Roedel <joerg.roedel at amd.com> wrote:

> This patch add the dma_debug_driver= boot parameter to enable the driver
> filter for early boot.
> 

Please always update Documentation/kernel-parameters.txt when adding
new boot options.

> +static int __init parse_dma_debug_driver(char *str)
> +{
> +	int i;
> +
> +	for (i = 0; i < NAME_MAX_LEN - 1; ++i, ++str) {
> +		current_driver_name[i] = *str;
> +		if (*str == ' ' || *str == '\t' || isspace(*str) || *str == 0)

The comparisons with ' ' and '\t' are unneeded, surely?

> +			break;
> +	}
> +	current_driver_name[i] = 0;
> +
> +	if (current_driver_name[0])
> +		printk(KERN_INFO "DMA-API: enable driver filter for "
> +				 "driver [%s]\n", current_driver_name);
> +
> +
> +	return 1;
> +}
> +__setup("dma_debug_driver=", parse_dma_debug_driver);

The whole thing seems a bit overdone - take a look at some other __setup
functions, see what they're doing.  None of them bother looking for
spaces in the input - higher level code took care of that.

It's conventional for the name of a __setup function to end in "_setup".


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