diff options
Diffstat (limited to 'hicn-plugin/src/data_fwd.h')
| -rw-r--r-- | hicn-plugin/src/data_fwd.h | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/hicn-plugin/src/data_fwd.h b/hicn-plugin/src/data_fwd.h index ad41e7e39..d95f564c3 100644 --- a/hicn-plugin/src/data_fwd.h +++ b/hicn-plugin/src/data_fwd.h @@ -20,6 +20,27 @@ #include "pcs.h" +/** + * @file data_fwd.h + * + * This is the node encoutered by data packets after the hicn-data-pcslookup. + * This node has two goals: 1) clone/copy the vlib buffer as many time as the number + * of faces stored in the pit entry, 2) store a clone/copy of the vlib buffer in the CS. + * Unless there are memory issue (no more vlib buffer available to perform cloning/copy), + * a single vlib buffer received might results in several vlib buffer sent to the next + * vlib node (hicn4-iface-output or hicn6-iface-output). + * + * It must be noted that cloning is possible only if the lentgh of the data pointed by + * the vlib buffer is at least 256 bytes. This is due to an imposition in the vpp source + * code. In all the other cases the vlib buffer is copied. Cloning is performed by advancing + * the vlib buffer of 256 bytes and a new vlib buffer is created and chained in from of the received + * buffer. Additionally, the 256 bytes removed (advanced) from the received vlib buffer are + * copied in the head vlib buffer. In case of multiple cloning for the same vlib buffer, this + * mechanism allows us to have a different hICN header for each clone (+ the same additional bytes + * due to the vpp restriction on cloning). + */ + + /* Trace context struct */ typedef struct { @@ -33,7 +54,6 @@ typedef enum { HICN_DATA_FWD_NEXT_V4_LOOKUP, HICN_DATA_FWD_NEXT_V6_LOOKUP, - HICN_DATA_FWD_NEXT_PUSH, HICN_DATA_FWD_NEXT_IFACE4_OUT, HICN_DATA_FWD_NEXT_IFACE6_OUT, HICN_DATA_FWD_NEXT_ERROR_DROP, @@ -41,7 +61,7 @@ typedef enum } hicn_data_fwd_next_t; /** - *@brief Create a maximum of 256 clones of buffer and store them + * @brief Create a maximum of 256 clones of buffer and store them * in the supplied array. Unlike the original function in the vlib * library, we don't prevent cloning if n_buffer==1 and if * s->current_length <= head_end_offset + CLIB_CACHE_LINE_BYTES * 2. |