[dpdk-dev] [PATCH v2 17/17] libte_acl: remove unused macros.

Thomas Monjalon thomas.monjalon at 6wind.com
Mon Jan 19 18:17:35 CET 2015


2015-01-12 19:16, Konstantin Ananyev:
>  /*
> + * ACL RT structure is a set of multibit tries (with stride == 8)
> + * represented by an array of transitions. The next position is calculated
> + * based on the current position and the input byte.
> + * Each transition is 64 bit value with the following format:
> + * | node_type_specific : 32 | node_type : 3 | node_addr : 29 |
> + * For all node types except RTE_ACL_NODE_MATCH, node_addr is an index
> + * to the start of the node in the transtions array.
> + * Few different node types are used:
> + * RTE_ACL_NODE_MATCH:
> + * node_addr value is and index into an array that contains the return value
> + * and its priority for each category.
> + * Upper 32 bits of the transtion value are not used for that node type.
> + * RTE_ACL_NODE_QRANGE:
> + * that node consist of up to 5 transitions.
> + * Upper 32 bits are interpreted as 4 signed character values which
> + * are ordered from smallest(INT8_MIN) to largest (INT8_MAX).
> + * These values define 5 ranges:
> + * INT8_MIN <= range[0]  <= ((int8_t *)&transition)[4]
> + * ((int8_t *)&transition)[4] < range[1] <= ((int8_t *)&transition)[5]
> + * ((int8_t *)&transition)[5] < range[2] <= ((int8_t *)&transition)[6]
> + * ((int8_t *)&transition)[6] < range[3] <= ((int8_t *)&transition)[7]
> + * ((int8_t *)&transition)[7] < range[4] <= INT8_MAX
> + * So for input byte value within range[i] i-th transition within that node
> + * will be used.
> + * RTE_ACL_NODE_SINGLE:
> + * always transitions to the same node regardless of the input value.
> + * RTE_ACL_NODE_DFA:
> + * that node consits of up to 256 transitions.
> + * In attempt to conserve space all transitions are divided into 4 consecutive
> + * groups, by 64 transitions per group:
> + * group64[i] contains transitions[i * 64, .. i * 64 + 63].
> + * Upper 32 bits are interpreted as 4 unsigned character values one per group,
> + * which contain index to the start of the given group within the node.
> + * So to calculate transition index within the node for given input byte value:
> + * input_byte - ((uint8_t *)&transition)[4 + input_byte / 64].
> + */

It's maybe an error. You were only supposed to remove some macros in this patch.

-- 
Thomas


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