Re: [PATCH RESEND iwl-next 2/2] ice: Add switch recipe reusing feature

[Simon Horman <horms@kernel.org>]

On Tue, Jan 30, 2024 at 10:51:46AM +0800, Steven Zou wrote:
> New E810 firmware supports the corresponding functionality, so the driver
> allows PFs to subscribe the same switch recipes. Then when the PF is done
> with a switch recipes, the PF can ask firmware to free that switch recipe.
> 
> When users configure a rule to PFn into E810 switch component, if there is
> no existing recipe matching this rule's pattern, the driver will request
> firmware to allocate and return a new recipe resource for the rule by
> calling ice_add_sw_recipe() and ice_alloc_recipe(). If there is an existing
> recipe matching this rule's pattern with different key value, or this is a
> same second rule to PFm into switch component, the driver checks out this
> recipe by calling ice_find_recp(), the driver will tell firmware to share
> using this same recipe resource by calling ice_subscribable_recp_shared()
> and ice_subscribe_recipe().
> 
> When firmware detects that all subscribing PFs have freed the switch
> recipe, firmware will free the switch recipe so that it can be reused.
> 
> This feature also fixes a problem where all switch recipes would eventually
> be exhausted because switch recipes could not be freed, as freeing a shared
> recipe could potentially break other PFs that were using it.
> 
> Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
> Reviewed-by: Andrii Staikov <andrii.staikov@intel.com>
> Signed-off-by: Steven Zou <steven.zou@intel.com>

Reviewed-by: Simon Horman <horms@kernel.org>