Re: [PATCH 1/6] firewire: core: reduce stack usage in bus reset tasklet

[pageexec@freemail.hu]

On 6 Sep 2009 at 18:48, Stefan Richter wrote:

> Index: linux-2.6.31-rc9/drivers/firewire/core-card.c
> ===================================================================
> --- linux-2.6.31-rc9.orig/drivers/firewire/core-card.c
> +++ linux-2.6.31-rc9/drivers/firewire/core-card.c
> @@ -38,16 +38,21 @@
>  
>  #include "core.h"
>  
> -int fw_compute_block_crc(u32 *block)
> +int fw_compute_block_crc(u32 *block, gfp_t flags)
>  {
> -	__be32 be32_block[256];
> -	int i, length;
> +	static __be32 *be32_block;
       ^^^^^^

did you actually mean that to be static? if so, then you might as well allocate the
buffer statically and not worry about a runtime allocation failure.

> +	int i, length = (*block >> 16) & 0xff;
> +
> +	be32_block = kmalloc(length * 4, flags);
> +	if (WARN_ON(!be32_block))
> +		goto out;
>  
> -	length = (*block >> 16) & 0xff;
>  	for (i = 0; i < length; i++)
>  		be32_block[i] = cpu_to_be32(block[i + 1]);
>  	*block |= crc_itu_t(0, (u8 *) be32_block, length * 4);
>  
> +	kfree(be32_block);
> + out:
>  	return length;
>  }