Re: [patch net-next 3/4] mlxsw: Add interface to access registers and process events

[Andy Gospodarek <gospo@cumulusnetworks.com>]

On Thu, Jul 23, 2015 at 05:43:35PM +0200, Jiri Pirko wrote:
> From: Ido Schimmel <idosch@mellanox.com>
> 
> Add the ability to construct mailbox-style register access messages
> called EMADs with provisions to construct and parse the registers payload.
> Implement EMAD transaction layer which is responsible for the reliable
> transmission of EMADs.
> Also, add an infrastructure used by the switch driver to register for
> particular events generated by the device.
> 
> Signed-off-by: Ido Schimmel <idosch@mellanox.com>
> Signed-off-by: Jiri Pirko <jiri@mellanox.com>
> Signed-off-by: Elad Raz <eladr@mellanox.com>
> ---
>  drivers/net/ethernet/mellanox/mlxsw/core.c |  736 ++++++++++++++++
>  drivers/net/ethernet/mellanox/mlxsw/core.h |   21 +
>  drivers/net/ethernet/mellanox/mlxsw/emad.h |  127 +++
>  drivers/net/ethernet/mellanox/mlxsw/port.h |   19 +
>  drivers/net/ethernet/mellanox/mlxsw/reg.h  | 1289 ++++++++++++++++++++++++++++
>  5 files changed, 2192 insertions(+)
>  create mode 100644 drivers/net/ethernet/mellanox/mlxsw/emad.h
>  create mode 100644 drivers/net/ethernet/mellanox/mlxsw/reg.h
> 
> diff --git a/drivers/net/ethernet/mellanox/mlxsw/core.c b/drivers/net/ethernet/mellanox/mlxsw/core.c
> index 211ec9b..bd0f692 100644
> --- a/drivers/net/ethernet/mellanox/mlxsw/core.c
> +++ b/drivers/net/ethernet/mellanox/mlxsw/core.c
[...]
> +	struct list_head event_listener_list;
> +	struct {
> +		struct sk_buff *resp_skb;
> +		u64 tid;
> +		wait_queue_head_t wait;
> +		bool trans_active;
> +		struct mutex lock; /* One EMAD transaction at a time. */
> +		bool use_emad;
> +	} emad;
>  	struct mlxsw_core_pcpu_stats __percpu *pcpu_stats;
>  	struct dentry *dbg_dir;
>  	struct {
[...]
>  	}
>  
>  	INIT_LIST_HEAD(&mlxsw_core->rx_listener_list);
> +	INIT_LIST_HEAD(&mlxsw_core->event_listener_list);
>  	mlxsw_core->driver = mlxsw_driver;
>  	mlxsw_core->bus = mlxsw_bus;
>  	mlxsw_core->bus_priv = bus_priv;
[...]
> +	/* No reason to save item if we did not manage to register an RX
> +	 * listener for it.
> +	 */
> +	list_add_rcu(&el_item->list, &mlxsw_core->event_listener_list);
> +

I see where 'event_listener_list' is defined and where entries are
added/removed, but where is the code that would receive these events and
presumably search this list so all handlers registered (currently just
PUDE) can handle events?