On Wed, Nov 05, 2014 at 03:30:37PM +0200, Qinglai Xiao wrote:
> User defined tag calculation has access to mbuf.
> Default tag is RSS hash result.
>
Interesting idea.
Did you investigate was there any performance improvement or regression
comparing
whether the callback was called per-packet as packets were dequeued for
distribution
(i.e. how you have things now in your patch), compared to calling
the callback in a loop to extract the tags for all packets initially? I suspect
there probably isn't much performance difference either way, but it may be worth
checking.
One other point, is that I think the callback to extract the tag should have
additional parameters - at least one, if not two. I would suggest that the
distributor pointer be passed in, as well as an arbitrary void * pointer.
Regards,
/Bruce
> Signed-off-by: Qinglai Xiao <jigsaw at gmail.com>
> ---
> 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
>
