Re: [RFC-v4 07/12] iscsi-target: Add CHAP Authentication support using libcrypto

[Mike Christie <michaelc@cs.wisc.edu>]

On 03/20/2011 04:31 AM, Nicholas A. Bellinger wrote:
> +static struct iscsi_chap *chap_server_open(
> +	struct iscsi_conn *conn,
> +	struct iscsi_node_auth *auth,
> +	const char *A_str,
> +	char *AIC_str,
> +	unsigned int *AIC_len)

Lot of mixed cases like this and below in the patch.



> +
> +static int chap_server_compute_md5(
> +	struct iscsi_conn *conn,
> +	struct iscsi_node_auth *auth,
> +	char *NR_in_ptr,
> +	char *NR_out_ptr,
> +	unsigned int *NR_out_len)



> +	return 2;
> +}
> diff --git a/drivers/target/iscsi/iscsi_target_auth.h b/drivers/target/iscsi/iscsi_target_auth.h
> new file mode 100644
> index 0000000..17b042d
> --- /dev/null
> +++ b/drivers/target/iscsi/iscsi_target_auth.h



> +
> +struct iscsi_chap {
> +	unsigned char	digest_type;
> +	unsigned char	id;
> +	unsigned char	challenge[CHAP_CHALLENGE_LENGTH];
> +	unsigned int	challenge_len;
> +	unsigned int	authenticate_target;
> +	unsigned int	chap_state;
> +} ____cacheline_aligned;
> +

Why are almost all structs in the patches ____cacheline_aligned? Is it 
something we are just doing now, or does this affect performance somehow 
even though the struct is not used in a perf path?