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

From: Simon Horman <[email-masked]>
Date: Tue, 5 Dec 2023 19:15:38 +0000

+ Ivan Vecera <[email-masked]>

On Fri, Dec 01, 2023 at 02:25:02PM +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 <[email-masked]>
> Reviewed-by: Andrii Staikov <[email-masked]>
> Signed-off-by: Steven Zou <[email-masked]>

Hi Ivan,

with my upstream hat on, I'd be most grateful if you could review this.

> ---
>  .../net/ethernet/intel/ice/ice_adminq_cmd.h   |   2 +
>  drivers/net/ethernet/intel/ice/ice_common.c   |   2 +
>  drivers/net/ethernet/intel/ice/ice_switch.c   | 187 ++++++++++++++++--
>  drivers/net/ethernet/intel/ice/ice_switch.h   |   1 +
>  drivers/net/ethernet/intel/ice/ice_type.h     |   2 +
>  5 files changed, 177 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/ice/ice_adminq_cmd.h b/drivers/net/ethernet/intel/ice/ice_adminq_cmd.h
> index c2b3ccce3124..2654aaad9a51 100644
> --- a/drivers/net/ethernet/intel/ice/ice_adminq_cmd.h
> +++ b/drivers/net/ethernet/intel/ice/ice_adminq_cmd.h
> @@ -264,6 +264,8 @@ struct ice_aqc_set_port_params {
>  #define ICE_AQC_RES_TYPE_FLAG_SHARED			BIT(7)
>  #define ICE_AQC_RES_TYPE_FLAG_SCAN_BOTTOM		BIT(12)
>  #define ICE_AQC_RES_TYPE_FLAG_IGNORE_INDEX		BIT(13)
> +#define ICE_AQC_RES_TYPE_FLAG_SUBSCRIBE_SHARED		BIT(14)
> +#define ICE_AQC_RES_TYPE_FLAG_SUBSCRIBE_CTL		BIT(15)
>  
>  #define ICE_AQC_RES_TYPE_FLAG_DEDICATED			0x00
>  
> diff --git a/drivers/net/ethernet/intel/ice/ice_common.c b/drivers/net/ethernet/intel/ice/ice_common.c
> index 8df151dd0c90..5bfec6bb759b 100644
> --- a/drivers/net/ethernet/intel/ice/ice_common.c
> +++ b/drivers/net/ethernet/intel/ice/ice_common.c
> @@ -1321,6 +1321,8 @@ int ice_init_hw(struct ice_hw *hw)
>  	if (status)
>  		goto err_unroll_fltr_mgmt_struct;
>  	mutex_init(&hw->tnl_lock);
> +	ice_init_chk_recipe_reuse_support(hw);
> +
>  	return 0;
>  
>  err_unroll_fltr_mgmt_struct:
> diff --git a/drivers/net/ethernet/intel/ice/ice_switch.c b/drivers/net/ethernet/intel/ice/ice_switch.c
> index 3cee603b187f..b926c045ebec 100644
> --- a/drivers/net/ethernet/intel/ice/ice_switch.c
> +++ b/drivers/net/ethernet/intel/ice/ice_switch.c
> @@ -2074,6 +2074,18 @@ ice_aq_get_recipe_to_profile(struct ice_hw *hw, u32 profile_id, u64 *r_assoc,
>  	return status;
>  }
>  
> +/**
> + * ice_init_chk_recipe_reuse_support - check if recipe reuse is supported
> + * @hw: pointer to the hardware structure
> + */
> +void ice_init_chk_recipe_reuse_support(struct ice_hw *hw)
> +{
> +	struct ice_nvm_info *nvm = &hw->flash.nvm;
> +
> +	hw->recp_reuse = (nvm->major == 0x4 && nvm->minor >= 0x30) ||
> +			 nvm->major > 0x4;
> +}
> +
>  /**
>   * ice_alloc_recipe - add recipe resource
>   * @hw: pointer to the hardware structure
> @@ -2083,12 +2095,16 @@ int ice_alloc_recipe(struct ice_hw *hw, u16 *rid)
>  {
>  	DEFINE_FLEX(struct ice_aqc_alloc_free_res_elem, sw_buf, elem, 1);
>  	u16 buf_len = __struct_size(sw_buf);
> +	u16 res_type;
>  	int status;
>  
>  	sw_buf->num_elems = cpu_to_le16(1);
> -	sw_buf->res_type = cpu_to_le16((ICE_AQC_RES_TYPE_RECIPE <<
> -					ICE_AQC_RES_TYPE_S) |
> -					ICE_AQC_RES_TYPE_FLAG_SHARED);
> +	res_type = FIELD_PREP(ICE_AQC_RES_TYPE_M, ICE_AQC_RES_TYPE_RECIPE);
> +	if (hw->recp_reuse)
> +		res_type |= ICE_AQC_RES_TYPE_FLAG_SUBSCRIBE_SHARED;
> +	else
> +		res_type |= ICE_AQC_RES_TYPE_FLAG_SHARED;
> +	sw_buf->res_type = cpu_to_le16(res_type);
>  	status = ice_aq_alloc_free_res(hw, sw_buf, buf_len,
>  				       ice_aqc_opc_alloc_res);
>  	if (!status)
> @@ -2097,6 +2113,70 @@ int ice_alloc_recipe(struct ice_hw *hw, u16 *rid)
>  	return status;
>  }
>  
> +/**
> + * ice_free_recipe_res - free recipe resource
> + * @hw: pointer to the hardware structure
> + * @rid: recipe ID to free
> + *
> + * Return: 0 on success, and others on error
> + */
> +static int ice_free_recipe_res(struct ice_hw *hw, u16 rid)
> +{
> +	return ice_free_hw_res(hw, ICE_AQC_RES_TYPE_RECIPE, 1, &rid);
> +}
> +
> +/**
> + * ice_release_recipe_res - disassociate and free recipe resource
> + * @hw: pointer to the hardware structure
> + * @recp: the recipe struct resource to unassociate and free
> + *
> + * Return: 0 on success, and others on error
> + */
> +static int ice_release_recipe_res(struct ice_hw *hw,
> +				  struct ice_sw_recipe *recp)
> +{
> +	DECLARE_BITMAP(r_bitmap, ICE_MAX_NUM_RECIPES);
> +	struct ice_switch_info *sw = hw->switch_info;
> +	u64 recp_assoc;
> +	u32 rid, prof;
> +	int status;
> +
> +	for_each_set_bit(rid, recp->r_bitmap, ICE_MAX_NUM_RECIPES) {
> +		for_each_set_bit(prof, recipe_to_profile[rid],
> +				 ICE_MAX_NUM_PROFILES) {
> +			status = ice_aq_get_recipe_to_profile(hw, prof,
> +							      &recp_assoc,
> +							      NULL);
> +			if (status)
> +				return status;
> +
> +			bitmap_from_arr64(r_bitmap, &recp_assoc,
> +					  ICE_MAX_NUM_RECIPES);
> +			bitmap_andnot(r_bitmap, r_bitmap, recp->r_bitmap,
> +				      ICE_MAX_NUM_RECIPES);
> +			bitmap_to_arr64(&recp_assoc, r_bitmap,
> +					ICE_MAX_NUM_RECIPES);
> +			ice_aq_map_recipe_to_profile(hw, prof,
> +						     recp_assoc, NULL);
> +
> +			clear_bit(rid, profile_to_recipe[prof]);
> +			clear_bit(prof, recipe_to_profile[rid]);
> +		}
> +
> +		status = ice_free_recipe_res(hw, rid);
> +		if (status)
> +			return status;
> +
> +		sw->recp_list[rid].recp_created = false;
> +		sw->recp_list[rid].adv_rule = false;
> +		memset(&sw->recp_list[rid].lkup_exts, 0,
> +		       sizeof(sw->recp_list[rid].lkup_exts));
> +		clear_bit(rid, recp->r_bitmap);
> +	}
> +
> +	return 0;
> +}
> +
>  /**
>   * ice_get_recp_to_prof_map - updates recipe to profile mapping
>   * @hw: pointer to hardware structure
> @@ -2146,6 +2226,7 @@ ice_collect_result_idx(struct ice_aqc_recipe_data_elem *buf,
>   * @recps: struct that we need to populate
>   * @rid: recipe ID that we are populating
>   * @refresh_required: true if we should get recipe to profile mapping from FW
> + * @is_add: flag of adding recipe
>   *
>   * This function is used to populate all the necessary entries into our
>   * bookkeeping so that we have a current list of all the recipes that are
> @@ -2153,7 +2234,7 @@ ice_collect_result_idx(struct ice_aqc_recipe_data_elem *buf,
>   */
>  static int
>  ice_get_recp_frm_fw(struct ice_hw *hw, struct ice_sw_recipe *recps, u8 rid,
> -		    bool *refresh_required)
> +		    bool *refresh_required, bool is_add)
>  {
>  	DECLARE_BITMAP(result_bm, ICE_MAX_FV_WORDS);
>  	struct ice_aqc_recipe_data_elem *tmp;
> @@ -2270,8 +2351,12 @@ ice_get_recp_frm_fw(struct ice_hw *hw, struct ice_sw_recipe *recps, u8 rid,
>  			recps[idx].chain_idx = ICE_INVAL_CHAIN_IND;
>  		}
>  
> -		if (!is_root)
> +		if (!is_root) {
> +			if (hw->recp_reuse && is_add)
> +				recps[idx].recp_created = true;
> +
>  			continue;
> +		}
>  
>  		/* Only do the following for root recipes entries */
>  		memcpy(recps[idx].r_bitmap, root_bufs.recipe_bitmap,
> @@ -2295,7 +2380,8 @@ ice_get_recp_frm_fw(struct ice_hw *hw, struct ice_sw_recipe *recps, u8 rid,
>  
>  	/* Copy result indexes */
>  	bitmap_copy(recps[rid].res_idxs, result_bm, ICE_MAX_FV_WORDS);
> -	recps[rid].recp_created = true;
> +	if (is_add)
> +		recps[rid].recp_created = true;
>  
>  err_unroll:
>  	kfree(tmp);
> @@ -4575,12 +4661,13 @@ static struct ice_protocol_entry ice_prot_id_tbl[ICE_PROTOCOL_LAST] = {
>   * @hw: pointer to the hardware structure
>   * @lkup_exts: extension sequence to match
>   * @rinfo: information regarding the rule e.g. priority and action info
> + * @is_add: flag of adding recipe
>   *
>   * Returns index of matching recipe, or ICE_MAX_NUM_RECIPES if not found.
>   */
>  static u16
>  ice_find_recp(struct ice_hw *hw, struct ice_prot_lkup_ext *lkup_exts,
> -	      const struct ice_adv_rule_info *rinfo)
> +	      const struct ice_adv_rule_info *rinfo, bool is_add)
>  {
>  	bool refresh_required = true;
>  	struct ice_sw_recipe *recp;
> @@ -4594,11 +4681,12 @@ ice_find_recp(struct ice_hw *hw, struct ice_prot_lkup_ext *lkup_exts,
>  		 * entry update it in our SW bookkeeping and continue with the
>  		 * matching.
>  		 */
> -		if (!recp[i].recp_created)
> +		if (hw->recp_reuse) {
>  			if (ice_get_recp_frm_fw(hw,
>  						hw->switch_info->recp_list, i,
> -						&refresh_required))
> +						&refresh_required, is_add))
>  				continue;
> +		}
>  
>  		/* Skip inverse action recipes */
>  		if (recp[i].root_buf && recp[i].root_buf->content.act_ctrl &
> @@ -5279,6 +5367,49 @@ ice_get_compat_fv_bitmap(struct ice_hw *hw, struct ice_adv_rule_info *rinfo,
>  	ice_get_sw_fv_bitmap(hw, prof_type, bm);
>  }
>  
> +/**
> + * ice_subscribe_recipe - subscribe to an existing recipe
> + * @hw: pointer to the hardware structure
> + * @rid: recipe ID to subscribe to
> + *
> + * Return: 0 on success, and others on error
> + */
> +static int ice_subscribe_recipe(struct ice_hw *hw, u16 rid)
> +{
> +	DEFINE_FLEX(struct ice_aqc_alloc_free_res_elem, sw_buf, elem, 1);
> +	u16 buf_len = __struct_size(sw_buf);
> +	u16 res_type;
> +	int status;
> +
> +	/* Prepare buffer to allocate resource */
> +	sw_buf->num_elems = cpu_to_le16(1);
> +	res_type = FIELD_PREP(ICE_AQC_RES_TYPE_M, ICE_AQC_RES_TYPE_RECIPE) |
> +		   ICE_AQC_RES_TYPE_FLAG_SUBSCRIBE_SHARED |
> +		   ICE_AQC_RES_TYPE_FLAG_SUBSCRIBE_CTL;
> +	sw_buf->res_type = cpu_to_le16(res_type);
> +
> +	sw_buf->elem[0].e.sw_resp = cpu_to_le16(rid);
> +
> +	status = ice_aq_alloc_free_res(hw, sw_buf, buf_len,
> +				       ice_aqc_opc_alloc_res);
> +
> +	return status;
> +}
> +
> +/**
> + * ice_subscribable_recp_shared - share an existing subscribable recipe
> + * @hw: pointer to the hardware structure
> + * @rid: recipe ID to subscribe to
> + */
> +static void ice_subscribable_recp_shared(struct ice_hw *hw, u16 rid)
> +{
> +	struct ice_sw_recipe *recps = hw->switch_info->recp_list;
> +	u16 sub_rid;
> +
> +	for_each_set_bit(sub_rid, recps[rid].r_bitmap, ICE_MAX_NUM_RECIPES)
> +		ice_subscribe_recipe(hw, sub_rid);
> +}
> +
>  /**
>   * ice_add_adv_recipe - Add an advanced recipe that is not part of the default
>   * @hw: pointer to hardware structure
> @@ -5301,6 +5432,7 @@ ice_add_adv_recipe(struct ice_hw *hw, struct ice_adv_lkup_elem *lkups,
>  	struct ice_sw_fv_list_entry *tmp;
>  	struct ice_sw_recipe *rm;
>  	int status = 0;
> +	u16 rid_tmp;
>  	u8 i;
>  
>  	if (!lkups_cnt)
> @@ -5378,10 +5510,14 @@ ice_add_adv_recipe(struct ice_hw *hw, struct ice_adv_lkup_elem *lkups,
>  	}
>  
>  	/* Look for a recipe which matches our requested fv / mask list */
> -	*rid = ice_find_recp(hw, lkup_exts, rinfo);
> -	if (*rid < ICE_MAX_NUM_RECIPES)
> +	*rid = ice_find_recp(hw, lkup_exts, rinfo, true);
> +	if (*rid < ICE_MAX_NUM_RECIPES) {
>  		/* Success if found a recipe that match the existing criteria */
> +		if (hw->recp_reuse)
> +			ice_subscribable_recp_shared(hw, *rid);
> +
>  		goto err_unroll;
> +	}
>  
>  	rm->tun_type = rinfo->tun_type;
>  	/* Recipe we need does not exist, add a recipe */
> @@ -5400,14 +5536,14 @@ ice_add_adv_recipe(struct ice_hw *hw, struct ice_adv_lkup_elem *lkups,
>  		status = ice_aq_get_recipe_to_profile(hw, fvit->profile_id,
>  						      &recp_assoc, NULL);
>  		if (status)
> -			goto err_unroll;
> +			goto err_free_recipe;
>  
>  		bitmap_from_arr64(r_bitmap, &recp_assoc, ICE_MAX_NUM_RECIPES);
>  		bitmap_or(r_bitmap, r_bitmap, rm->r_bitmap,
>  			  ICE_MAX_NUM_RECIPES);
>  		status = ice_acquire_change_lock(hw, ICE_RES_WRITE);
>  		if (status)
> -			goto err_unroll;
> +			goto err_free_recipe;
>  
>  		bitmap_to_arr64(&recp_assoc, r_bitmap, ICE_MAX_NUM_RECIPES);
>  		status = ice_aq_map_recipe_to_profile(hw, fvit->profile_id,
> @@ -5415,7 +5551,7 @@ ice_add_adv_recipe(struct ice_hw *hw, struct ice_adv_lkup_elem *lkups,
>  		ice_release_change_lock(hw);
>  
>  		if (status)
> -			goto err_unroll;
> +			goto err_free_recipe;
>  
>  		/* Update profile to recipe bitmap array */
>  		bitmap_copy(profile_to_recipe[fvit->profile_id], r_bitmap,
> @@ -5429,6 +5565,16 @@ ice_add_adv_recipe(struct ice_hw *hw, struct ice_adv_lkup_elem *lkups,
>  	*rid = rm->root_rid;
>  	memcpy(&hw->switch_info->recp_list[*rid].lkup_exts, lkup_exts,
>  	       sizeof(*lkup_exts));
> +	goto err_unroll;
> +
> +err_free_recipe:
> +	if (hw->recp_reuse) {
> +		for_each_set_bit(rid_tmp, rm->r_bitmap, ICE_MAX_NUM_RECIPES) {
> +			if (!ice_free_recipe_res(hw, rid_tmp))
> +				clear_bit(rid_tmp, rm->r_bitmap);
> +		}
> +	}
> +
>  err_unroll:
>  	list_for_each_entry_safe(r_entry, r_tmp, &rm->rg_list, l_entry) {
>  		list_del(&r_entry->l_entry);
> @@ -6431,7 +6577,7 @@ ice_rem_adv_rule(struct ice_hw *hw, struct ice_adv_lkup_elem *lkups,
>  			return -EIO;
>  	}
>  
> -	rid = ice_find_recp(hw, &lkup_exts, rinfo);
> +	rid = ice_find_recp(hw, &lkup_exts, rinfo, false);
>  	/* If did not find a recipe that match the existing criteria */
>  	if (rid == ICE_MAX_NUM_RECIPES)
>  		return -EINVAL;
> @@ -6475,14 +6621,21 @@ ice_rem_adv_rule(struct ice_hw *hw, struct ice_adv_lkup_elem *lkups,
>  					 ice_aqc_opc_remove_sw_rules, NULL);
>  		if (!status || status == -ENOENT) {
>  			struct ice_switch_info *sw = hw->switch_info;
> +			struct ice_sw_recipe *r_list = sw->recp_list;
>  
>  			mutex_lock(rule_lock);
>  			list_del(&list_elem->list_entry);
>  			devm_kfree(ice_hw_to_dev(hw), list_elem->lkups);
>  			devm_kfree(ice_hw_to_dev(hw), list_elem);
>  			mutex_unlock(rule_lock);
> -			if (list_empty(&sw->recp_list[rid].filt_rules))
> -				sw->recp_list[rid].adv_rule = false;
> +			if (list_empty(&r_list[rid].filt_rules)) {
> +				r_list[rid].adv_rule = false;
> +
> +				/* All rules for this recipe are now removed */
> +				if (hw->recp_reuse)
> +					ice_release_recipe_res(hw,
> +							       &r_list[rid]);
> +			}
>  		}
>  		kfree(s_rule);
>  	}
> diff --git a/drivers/net/ethernet/intel/ice/ice_switch.h b/drivers/net/ethernet/intel/ice/ice_switch.h
> index 89ffa1b51b5a..9cf819b20d9c 100644
> --- a/drivers/net/ethernet/intel/ice/ice_switch.h
> +++ b/drivers/net/ethernet/intel/ice/ice_switch.h
> @@ -429,5 +429,6 @@ ice_aq_get_recipe_to_profile(struct ice_hw *hw, u32 profile_id, u64 *r_assoc,
>  int
>  ice_aq_map_recipe_to_profile(struct ice_hw *hw, u32 profile_id, u64 r_assoc,
>  			     struct ice_sq_cd *cd);
> +void ice_init_chk_recipe_reuse_support(struct ice_hw *hw);
>  
>  #endif /* _ICE_SWITCH_H_ */
> diff --git a/drivers/net/ethernet/intel/ice/ice_type.h b/drivers/net/ethernet/intel/ice/ice_type.h
> index 2be3955e249e..4c756c2b6157 100644
> --- a/drivers/net/ethernet/intel/ice/ice_type.h
> +++ b/drivers/net/ethernet/intel/ice/ice_type.h
> @@ -862,6 +862,8 @@ struct ice_hw {
>  
>  	u16 max_burst_size;	/* driver sets this value */
>  
> +	u8 recp_reuse:1;	/* indicates whether FW supports recipe reuse */
> +
>  	/* Tx Scheduler values */
>  	u8 num_tx_sched_layers;
>  	u8 num_tx_sched_phys_layers;
> -- 
> 2.31.1
>