linux-generic: packet: add routines for manipulating reference counts

Signed-off-by: Bill Fischofer <bill.fischofer@linaro.org>
Reviewed-by: Dmitry Eremin-Solenikov <dmitry.ereminsolenikov@linaro.org>
Reviewed-and-tested-by: Yi He <yi.he@linaro.org>
Signed-off-by: Maxim Uvarov <maxim.uvarov@linaro.org>

2 files changed, 29 insertions, 0 deletions

diff --git a/platform/linux-generic/include/odp_packet_internal.h b/platform/linux-generic/include/odp_packet_internal.h
index 0542dd108..8c83966c5 100644
--- a/platform/linux-generic/include/odp_packet_internal.h
+++ b/platform/linux-generic/include/odp_packet_internal.h
@@ -254,6 +254,25 @@ static inline uint32_t packet_len(odp_packet_hdr_t *pkt_hdr)
 	return pkt_hdr->frame_len;
 }
 
+static inline uint32_t packet_ref_count(odp_packet_hdr_t *pkt_hdr)
+{
+	/* Breach the atomic type to do a peek at the ref count. This
+	 * is used to bypass atomic operations if ref_count == 1 for
+	 * performance reasons.
+	 */
+	return pkt_hdr->ref_count.v;
+}
+
+static inline void packet_ref_count_set(odp_packet_hdr_t *pkt_hdr, uint32_t n)
+{
+	/* Only used during init when there are no other possible
+	 * references to this pkt, so avoid the "atomic" overhead by
+	 * a controlled breach of the atomic type here. This saves
+	 * over 10% of the pathlength in routines like packet_alloc().
+	 */
+	pkt_hdr->ref_count.v = n;
+}
+
 static inline void packet_set_len(odp_packet_hdr_t *pkt_hdr, uint32_t len)
 {
 	pkt_hdr->frame_len = len;
diff --git a/platform/linux-generic/odp_packet.c b/platform/linux-generic/odp_packet.c
index af8c442e7..988045e40 100644
--- a/platform/linux-generic/odp_packet.c
+++ b/platform/linux-generic/odp_packet.c
@@ -61,6 +61,16 @@ static inline odp_buffer_t buffer_handle(odp_packet_hdr_t *pkt_hdr)
 	return (odp_buffer_t)pkt_hdr;
 }
 
+static inline void packet_ref_inc(odp_packet_hdr_t *pkt_hdr)
+{
+	odp_atomic_inc_u32(&pkt_hdr->ref_count);
+}
+
+static inline uint32_t packet_ref_dec(odp_packet_hdr_t *pkt_hdr)
+{
+	return odp_atomic_fetch_dec_u32(&pkt_hdr->ref_count);
+}
+
 static inline odp_packet_hdr_t *buf_to_packet_hdr(odp_buffer_t buf)
 {
 	return (odp_packet_hdr_t *)buf_hdl_to_hdr(buf);