Re: [PATCH 2/2] [IPV4] route: Dynamic hash table sizing.

[Eric Dumazet <dada1@cosmosbay.com>]

On Wednesday 09 August 2006 09:53, David Miller wrote:
> [IPV4] route: Dynamic hash table sizing.
>

 Excellent work David, Thank you !!!

> +static int ip_rt_hashsz_limit		= (8 * 1024 * 1024) / sizeof(void *);

__read_mostly ?




> +		hash = __rt_hash_code(list->fl.fl4_dst,
> +				      list->fl.fl4_src &
> +				      (iface << 5),
> +				      nhashmask);

I thought it was a XOR (^) , not a AND (&)


>  static int __init set_rhash_entries(char *str)
>  {
> +	unsigned long val;
> +
>  	if (!str)
>  		return 0;
> -	rhash_entries = simple_strtoul(str, &str, 0);
> +	val = simple_strtoul(str, &str, 0);
> +
> +	/* Only use it if it's a power-of-2. */
> +	if (!(val & (val - 1)))
> +		rhash_entries = val;
> +

Well, it breaks x86_64 machines that currently do rhash_entries=2000000
Why not round to the next/previous power of two as before ?

>  	return 1;
>  }
>  __setup("rhash_entries=", set_rhash_entries);
>

Thank you
Eric