[PATCH] Add user defined tag calculation callback to librte_distributor.

[Qinglai Xiao <jigsaw-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>]

User defined tag calculation has access to mbuf.
Default tag is RSS hash result.

Signed-off-by: Qinglai Xiao <jigsaw-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
---
 app/test/test_distributor.c              |    6 +++---
 app/test/test_distributor_perf.c         |    2 +-
 lib/librte_distributor/rte_distributor.c |   12 ++++++++++--
 lib/librte_distributor/rte_distributor.h |    7 ++++++-
 4 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/app/test/test_distributor.c b/app/test/test_distributor.c
index ce06436..6ea4943 100644
--- a/app/test/test_distributor.c
+++ b/app/test/test_distributor.c
@@ -452,7 +452,7 @@ int test_error_distributor_create_name(void)
 	char *name = NULL;
 
 	d = rte_distributor_create(name, rte_socket_id(),
-			rte_lcore_count() - 1);
+			rte_lcore_count() - 1, NULL);
 	if (d != NULL || rte_errno != EINVAL) {
 		printf("ERROR: No error on create() with NULL name param\n");
 		return -1;
@@ -467,7 +467,7 @@ int test_error_distributor_create_numworkers(void)
 {
 	struct rte_distributor *d = NULL;
 	d = rte_distributor_create("test_numworkers", rte_socket_id(),
-			RTE_MAX_LCORE + 10);
+			RTE_MAX_LCORE + 10, NULL);
 	if (d != NULL || rte_errno != EINVAL) {
 		printf("ERROR: No error on create() with num_workers > MAX\n");
 		return -1;
@@ -515,7 +515,7 @@ test_distributor(void)
 
 	if (d == NULL) {
 		d = rte_distributor_create("Test_distributor", rte_socket_id(),
-				rte_lcore_count() - 1);
+				rte_lcore_count() - 1, NULL);
 		if (d == NULL) {
 			printf("Error creating distributor\n");
 			return -1;
diff --git a/app/test/test_distributor_perf.c b/app/test/test_distributor_perf.c
index b04864c..507e446 100644
--- a/app/test/test_distributor_perf.c
+++ b/app/test/test_distributor_perf.c
@@ -227,7 +227,7 @@ test_distributor_perf(void)
 
 	if (d == NULL) {
 		d = rte_distributor_create("Test_perf", rte_socket_id(),
-				rte_lcore_count() - 1);
+				rte_lcore_count() - 1, NULL);
 		if (d == NULL) {
 			printf("Error creating distributor\n");
 			return -1;
diff --git a/lib/librte_distributor/rte_distributor.c b/lib/librte_distributor/rte_distributor.c
index 585ff88..78c92bd 100644
--- a/lib/librte_distributor/rte_distributor.c
+++ b/lib/librte_distributor/rte_distributor.c
@@ -97,6 +97,7 @@ struct rte_distributor {
 	union rte_distributor_buffer bufs[RTE_MAX_LCORE];
 
 	struct rte_distributor_returned_pkts returns;
+	rte_distributor_tag_fn tag_cb;
 };
 
 TAILQ_HEAD(rte_distributor_list, rte_distributor);
@@ -267,6 +268,7 @@ rte_distributor_process(struct rte_distributor *d,
 	struct rte_mbuf *next_mb = NULL;
 	int64_t next_value = 0;
 	uint32_t new_tag = 0;
+	rte_distributor_tag_fn tag_cb = d->tag_cb;
 	unsigned ret_start = d->returns.start,
 			ret_count = d->returns.count;
 
@@ -282,7 +284,11 @@ rte_distributor_process(struct rte_distributor *d,
 			next_mb = mbufs[next_idx++];
 			next_value = (((int64_t)(uintptr_t)next_mb)
 					<< RTE_DISTRIB_FLAG_BITS);
-			new_tag = (next_mb->hash.rss | 1);
+			if (tag_cb) {
+				new_tag = tag_cb(next_mb);
+			} else {
+				new_tag = (next_mb->hash.rss | 1);
+			}
 
 			uint32_t match = 0;
 			unsigned i;
@@ -401,7 +407,8 @@ rte_distributor_clear_returns(struct rte_distributor *d)
 struct rte_distributor *
 rte_distributor_create(const char *name,
 		unsigned socket_id,
-		unsigned num_workers)
+		unsigned num_workers,
+		rte_distributor_tag_fn tag_cb)
 {
 	struct rte_distributor *d;
 	struct rte_distributor_list *distributor_list;
@@ -435,6 +442,7 @@ rte_distributor_create(const char *name,
 	d = mz->addr;
 	snprintf(d->name, sizeof(d->name), "%s", name);
 	d->num_workers = num_workers;
+	d->tag_cb = tag_cb;
 
 	rte_rwlock_write_lock(RTE_EAL_TAILQ_RWLOCK);
 	TAILQ_INSERT_TAIL(distributor_list, d, next);
diff --git a/lib/librte_distributor/rte_distributor.h b/lib/librte_distributor/rte_distributor.h
index ec0d74a..844d325 100644
--- a/lib/librte_distributor/rte_distributor.h
+++ b/lib/librte_distributor/rte_distributor.h
@@ -52,6 +52,9 @@ extern "C" {
 
 struct rte_distributor;
 
+typedef uint32_t (*rte_distributor_tag_fn)(struct rte_mbuf *);
+/**< User defined tag calculation function */
+
 /**
  * Function to create a new distributor instance
  *
@@ -65,12 +68,14 @@ struct rte_distributor;
  * @param num_workers
  *   The maximum number of workers that will request packets from this
  *   distributor
+ * @param tag_cb
+ *   The callback function for calculation of user defined tag.
  * @return
  *   The newly created distributor instance
  */
 struct rte_distributor *
 rte_distributor_create(const char *name, unsigned socket_id,
-		unsigned num_workers);
+		unsigned num_workers, rte_distributor_tag_fn tag_cb);
 
 /*  *** APIS to be called on the distributor lcore ***  */
 /*
-- 
1.7.1