lib: Call nexthop g_addr hashes together

When hashing a nexthop, shove all the nexthop g_addr data together
and pass it as one call to jhash2() to optimize a bit better.

Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>

1 files changed, 16 insertions, 4 deletions

diff --git a/lib/nexthop.c b/lib/nexthop.c
index e68e605a6f..da7c934efa 100644
--- a/lib/nexthop.c
+++ b/lib/nexthop.c
@@ -374,16 +374,28 @@ unsigned int nexthop_level(struct nexthop *nexthop)
 	return rv;
 }
 
+#define GATE_SIZE 4 /* Number of uint32_t words in struct g_addr */
+
 uint32_t nexthop_hash(const struct nexthop *nexthop)
 {
+
 	uint32_t key = 0x45afe398;
+	uint32_t gate_src_rmap_raw[GATE_SIZE * 3] = {};
 
 	key = jhash_3words(nexthop->type, nexthop->vrf_id,
 			   nexthop->nh_label_type, key);
-	/* gate and blackhole are together in a union */
-	key = jhash(&nexthop->gate, sizeof(nexthop->gate), key);
-	key = jhash(&nexthop->src, sizeof(nexthop->src), key);
-	key = jhash(&nexthop->rmap_src, sizeof(nexthop->rmap_src), key);
+
+	assert(((sizeof(nexthop->gate) + sizeof(nexthop->src)
+		 + sizeof(nexthop->rmap_src))
+		/ 3)
+	       == (GATE_SIZE * sizeof(uint32_t)));
+
+	memcpy(gate_src_rmap_raw, &nexthop->gate, GATE_SIZE);
+	memcpy(gate_src_rmap_raw + GATE_SIZE, &nexthop->src, GATE_SIZE);
+	memcpy(gate_src_rmap_raw + (2 * GATE_SIZE), &nexthop->rmap_src,
+	       GATE_SIZE);
+
+	key = jhash2(gate_src_rmap_raw, (GATE_SIZE * 3), key);
 
 	if (nexthop->nh_label) {
 		int labels = nexthop->nh_label->num_labels;