mlxsw: core_acl_flex_keys: Fill blocks with high entropy first

The previous patches prepared the code to allow separating between
choosing blocks and filling blocks.

Do not add blocks as part of the loop that chooses them. When all the
required blocks are set in the bitmap 'chosen_blocks_bm', start filling
blocks. Iterate over the bitmap twice - first add only blocks that are
marked with 'high_entropy' flag. Then, fill the rest of the blocks.

The idea is to place key blocks with high entropy in blocks 0 to 5. See
more details in previous patches.
Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/core_acl_flex_keys.c

@@ -221,6 +221,36 @@ static int mlxsw_afk_picker_key_info_add(struct mlxsw_afk *mlxsw_afk,
 	return 0;
 }
 
+static int mlxsw_afk_keys_fill(struct mlxsw_afk *mlxsw_afk,
+			       unsigned long *chosen_blocks_bm,
+			       struct mlxsw_afk_picker *picker,
+			       struct mlxsw_afk_key_info *key_info)
+{
+	int i, err;
+
+	/* First fill only key blocks with high_entropy. */
+	for_each_set_bit(i, chosen_blocks_bm, mlxsw_afk->blocks_count) {
+		if (!mlxsw_afk->blocks[i].high_entropy)
+			continue;
+
+		err = mlxsw_afk_picker_key_info_add(mlxsw_afk, picker, i,
+						    key_info);
+		if (err)
+			return err;
+		__clear_bit(i, chosen_blocks_bm);
+	}
+
+	/* Fill the rest of key blocks. */
+	for_each_set_bit(i, chosen_blocks_bm, mlxsw_afk->blocks_count) {
+		err = mlxsw_afk_picker_key_info_add(mlxsw_afk, picker, i,
+						    key_info);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
 static int mlxsw_afk_picker(struct mlxsw_afk *mlxsw_afk,
 			    struct mlxsw_afk_key_info *key_info,
 			    struct mlxsw_afk_element_usage *elusage)
@@ -275,16 +305,13 @@ static int mlxsw_afk_picker(struct mlxsw_afk *mlxsw_afk,
 			  picker[block_index].chosen_element,
 			  MLXSW_AFK_ELEMENT_MAX);
 
-		err = mlxsw_afk_picker_key_info_add(mlxsw_afk, picker,
-						    block_index, key_info);
-		if (err)
-			goto out;
 		mlxsw_afk_picker_subtract_hits(mlxsw_afk, picker, block_index);
 
 	} while (!bitmap_equal(elusage_chosen, elusage->usage,
 			       MLXSW_AFK_ELEMENT_MAX));
 
-	err = 0;
+	err = mlxsw_afk_keys_fill(mlxsw_afk, chosen_blocks_bm, picker,
+				  key_info);
 out:
 	bitmap_free(chosen_blocks_bm);
 err_bitmap_alloc: