There was a compile time setting to enable a ring to yield when
it entered a loop in mp or mc rings waiting for the tail pointer update.
Build time settings are not recommended for enabling/disabling features,
and since this was off by default, remove it completely. If needed, a
runtime enabled equivalent can be used.
Signed-off-by: Bruce Richardson <bruce.richard...@intel.com>
---
config/common_base | 1 -
doc/guides/prog_guide/env_abstraction_layer.rst | 5 ----
doc/guides/rel_notes/release_17_05.rst | 1 +
lib/librte_ring/rte_ring.h | 35 +++++--------------------
4 files changed, 7 insertions(+), 35 deletions(-)
diff --git a/config/common_base b/config/common_base
index b3d8272..d5beadd 100644
--- a/config/common_base
+++ b/config/common_base
@@ -447,7 +447,6 @@ CONFIG_RTE_LIBRTE_PMD_NULL_CRYPTO=y
# Compile librte_ring
#
CONFIG_RTE_LIBRTE_RING=y
-CONFIG_RTE_RING_PAUSE_REP_COUNT=0
#
# Compile librte_mempool
diff --git a/doc/guides/prog_guide/env_abstraction_layer.rst
b/doc/guides/prog_guide/env_abstraction_layer.rst
index 10a10a8..7c39cd2 100644
--- a/doc/guides/prog_guide/env_abstraction_layer.rst
+++ b/doc/guides/prog_guide/env_abstraction_layer.rst
@@ -352,11 +352,6 @@ Known Issues
3. It MUST not be used by multi-producer/consumer pthreads, whose scheduling
policies are SCHED_FIFO or SCHED_RR.
- ``RTE_RING_PAUSE_REP_COUNT`` is defined for rte_ring to reduce contention.
It's mainly for case 2, a yield is issued after number of times pause repeat.
-
- It adds a sched_yield() syscall if the thread spins for too long while
waiting on the other thread to finish its operations on the ring.
- This gives the preempted thread a chance to proceed and finish with the ring
enqueue/dequeue operation.
-
+ rte_timer
Running ``rte_timer_manager()`` on a non-EAL pthread is not allowed.
However, resetting/stopping the timer from a non-EAL pthread is allowed.
diff --git a/doc/guides/rel_notes/release_17_05.rst
b/doc/guides/rel_notes/release_17_05.rst
index e0ebd71..c69ca8f 100644
--- a/doc/guides/rel_notes/release_17_05.rst
+++ b/doc/guides/rel_notes/release_17_05.rst
@@ -117,6 +117,7 @@ API Changes
* removed the build-time setting ``CONFIG_RTE_RING_SPLIT_PROD_CONS``
* removed the build-time setting ``CONFIG_RTE_LIBRTE_RING_DEBUG``
+ * removed the build-time setting ``CONFIG_RTE_RING_PAUSE_REP_COUNT``
ABI Changes
-----------
diff --git a/lib/librte_ring/rte_ring.h b/lib/librte_ring/rte_ring.h
index af7b7d4..2177954 100644
--- a/lib/librte_ring/rte_ring.h
+++ b/lib/librte_ring/rte_ring.h
@@ -114,11 +114,6 @@ enum rte_ring_queue_behavior {
#define RTE_RING_NAMESIZE (RTE_MEMZONE_NAMESIZE - \
sizeof(RTE_RING_MZ_PREFIX) + 1)
-#ifndef RTE_RING_PAUSE_REP_COUNT
-#define RTE_RING_PAUSE_REP_COUNT 0 /**< Yield after pause num of times, no
yield
- * if RTE_RING_PAUSE_REP not defined. */
-#endif
-
struct rte_memzone; /* forward declaration, so as not to require memzone.h */
#if RTE_CACHE_LINE_SIZE < 128
@@ -396,7 +391,7 @@ __rte_ring_mp_do_enqueue(struct rte_ring *r, void * const
*obj_table,
uint32_t cons_tail, free_entries;
const unsigned max = n;
int success;
- unsigned i, rep = 0;
+ unsigned int i;
uint32_t mask = r->mask;
int ret;
@@ -450,18 +445,9 @@ __rte_ring_mp_do_enqueue(struct rte_ring *r, void * const
*obj_table,
* If there are other enqueues in progress that preceded us,
* we need to wait for them to complete
*/
- while (unlikely(r->prod.tail != prod_head)) {
+ while (unlikely(r->prod.tail != prod_head))
rte_pause();
- /* Set RTE_RING_PAUSE_REP_COUNT to avoid spin too long waiting
- * for other thread finish. It gives pre-empted thread a chance
- * to proceed and finish with ring dequeue operation. */
- if (RTE_RING_PAUSE_REP_COUNT &&
- ++rep == RTE_RING_PAUSE_REP_COUNT) {
- rep = 0;
- sched_yield();
- }
- }
r->prod.tail = prod_next;
return ret;
}
@@ -494,7 +480,7 @@ __rte_ring_sp_do_enqueue(struct rte_ring *r, void * const
*obj_table,
{
uint32_t prod_head, cons_tail;
uint32_t prod_next, free_entries;
- unsigned i;
+ unsigned int i;
uint32_t mask = r->mask;
int ret;
@@ -571,7 +557,7 @@ __rte_ring_mc_do_dequeue(struct rte_ring *r, void
**obj_table,
uint32_t cons_next, entries;
const unsigned max = n;
int success;
- unsigned i, rep = 0;
+ unsigned int i;
uint32_t mask = r->mask;
/* Avoid the unnecessary cmpset operation below, which is also
@@ -616,18 +602,9 @@ __rte_ring_mc_do_dequeue(struct rte_ring *r, void
**obj_table,
* If there are other dequeues in progress that preceded us,
* we need to wait for them to complete
*/
- while (unlikely(r->cons.tail != cons_head)) {
+ while (unlikely(r->cons.tail != cons_head))
rte_pause();
- /* Set RTE_RING_PAUSE_REP_COUNT to avoid spin too long waiting
- * for other thread finish. It gives pre-empted thread a chance
- * to proceed and finish with ring dequeue operation. */
- if (RTE_RING_PAUSE_REP_COUNT &&
- ++rep == RTE_RING_PAUSE_REP_COUNT) {
- rep = 0;
- sched_yield();
- }
- }
r->cons.tail = cons_next;
return behavior == RTE_RING_QUEUE_FIXED ? 0 : n;
@@ -662,7 +639,7 @@ __rte_ring_sc_do_dequeue(struct rte_ring *r, void
**obj_table,
{
uint32_t cons_head, prod_tail;
uint32_t cons_next, entries;
- unsigned i;
+ unsigned int i;
uint32_t mask = r->mask;
cons_head = r->cons.head;
--
2.9.3
