* [PATCH v2] ring: add the second version of the RTS interface
@ 2025-01-05 15:09 Huichao Cai
0 siblings, 0 replies; 4+ messages in thread
From: Huichao Cai @ 2025-01-05 15:09 UTC (permalink / raw)
To: honnappa.nagarahalli, konstantin.v.ananyev, thomas; +Cc: dev
The timing of the update of the RTS enqueues/dequeues tail is
limited to the last enqueues/dequeues, which reduces concurrency,
so the RTS interface of the V2 version is added, which makes the tail
of the enqueues/dequeues not limited to the last enqueues/dequeues
and thus enables timely updates to increase concurrency.
Add some corresponding test cases.
Signed-off-by: Huichao Cai <chcchc88@163.com>
---
app/test/meson.build | 1 +
app/test/test_ring.c | 26 +++
app/test/test_ring_rts_v2_stress.c | 32 ++++
app/test/test_ring_stress.c | 3 +
app/test/test_ring_stress.h | 1 +
devtools/libabigail.abignore | 6 +
doc/guides/rel_notes/release_25_03.rst | 2 +
lib/ring/rte_ring.c | 54 ++++++-
lib/ring/rte_ring.h | 12 ++
lib/ring/rte_ring_core.h | 9 ++
lib/ring/rte_ring_elem.h | 18 +++
lib/ring/rte_ring_rts.h | 216 ++++++++++++++++++++++++-
lib/ring/rte_ring_rts_elem_pvt.h | 168 +++++++++++++++++++
13 files changed, 538 insertions(+), 10 deletions(-)
create mode 100644 app/test/test_ring_rts_v2_stress.c
diff --git a/app/test/meson.build b/app/test/meson.build
index d5cb6a7f7a..e3d8cef3fa 100644
--- a/app/test/meson.build
+++ b/app/test/meson.build
@@ -166,6 +166,7 @@ source_file_deps = {
'test_ring_mt_peek_stress_zc.c': ['ptr_compress'],
'test_ring_perf.c': ['ptr_compress'],
'test_ring_rts_stress.c': ['ptr_compress'],
+ 'test_ring_rts_v2_stress.c': ['ptr_compress'],
'test_ring_st_peek_stress.c': ['ptr_compress'],
'test_ring_st_peek_stress_zc.c': ['ptr_compress'],
'test_ring_stress.c': ['ptr_compress'],
diff --git a/app/test/test_ring.c b/app/test/test_ring.c
index ba1fec1de3..094f14b859 100644
--- a/app/test/test_ring.c
+++ b/app/test/test_ring.c
@@ -284,6 +284,19 @@ static const struct {
.felem = rte_ring_dequeue_bulk_elem,
},
},
+ {
+ .desc = "MP_RTS/MC_RTS V2 sync mode",
+ .api_type = TEST_RING_ELEM_BULK | TEST_RING_THREAD_DEF,
+ .create_flags = RING_F_MP_RTS_V2_ENQ | RING_F_MC_RTS_V2_DEQ,
+ .enq = {
+ .flegacy = rte_ring_enqueue_bulk,
+ .felem = rte_ring_enqueue_bulk_elem,
+ },
+ .deq = {
+ .flegacy = rte_ring_dequeue_bulk,
+ .felem = rte_ring_dequeue_bulk_elem,
+ },
+ },
{
.desc = "MP_HTS/MC_HTS sync mode",
.api_type = TEST_RING_ELEM_BULK | TEST_RING_THREAD_DEF,
@@ -349,6 +362,19 @@ static const struct {
.felem = rte_ring_dequeue_burst_elem,
},
},
+ {
+ .desc = "MP_RTS/MC_RTS V2 sync mode",
+ .api_type = TEST_RING_ELEM_BURST | TEST_RING_THREAD_DEF,
+ .create_flags = RING_F_MP_RTS_V2_ENQ | RING_F_MC_RTS_V2_DEQ,
+ .enq = {
+ .flegacy = rte_ring_enqueue_burst,
+ .felem = rte_ring_enqueue_burst_elem,
+ },
+ .deq = {
+ .flegacy = rte_ring_dequeue_burst,
+ .felem = rte_ring_dequeue_burst_elem,
+ },
+ },
{
.desc = "MP_HTS/MC_HTS sync mode",
.api_type = TEST_RING_ELEM_BURST | TEST_RING_THREAD_DEF,
diff --git a/app/test/test_ring_rts_v2_stress.c b/app/test/test_ring_rts_v2_stress.c
new file mode 100644
index 0000000000..6079366a7d
--- /dev/null
+++ b/app/test/test_ring_rts_v2_stress.c
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2020 Intel Corporation
+ */
+
+#include "test_ring_stress_impl.h"
+
+static inline uint32_t
+_st_ring_dequeue_bulk(struct rte_ring *r, void **obj, uint32_t n,
+ uint32_t *avail)
+{
+ return rte_ring_mc_rts_v2_dequeue_bulk(r, obj, n, avail);
+}
+
+static inline uint32_t
+_st_ring_enqueue_bulk(struct rte_ring *r, void * const *obj, uint32_t n,
+ uint32_t *free)
+{
+ return rte_ring_mp_rts_v2_enqueue_bulk(r, obj, n, free);
+}
+
+static int
+_st_ring_init(struct rte_ring *r, const char *name, uint32_t num)
+{
+ return rte_ring_init(r, name, num,
+ RING_F_MP_RTS_V2_ENQ | RING_F_MC_RTS_V2_DEQ);
+}
+
+const struct test test_ring_rts_v2_stress = {
+ .name = "MT_RTS_V2",
+ .nb_case = RTE_DIM(tests),
+ .cases = tests,
+};
diff --git a/app/test/test_ring_stress.c b/app/test/test_ring_stress.c
index 1af45e0fc8..94085acd5e 100644
--- a/app/test/test_ring_stress.c
+++ b/app/test/test_ring_stress.c
@@ -43,6 +43,9 @@ test_ring_stress(void)
n += test_ring_rts_stress.nb_case;
k += run_test(&test_ring_rts_stress);
+ n += test_ring_rts_v2_stress.nb_case;
+ k += run_test(&test_ring_rts_v2_stress);
+
n += test_ring_hts_stress.nb_case;
k += run_test(&test_ring_hts_stress);
diff --git a/app/test/test_ring_stress.h b/app/test/test_ring_stress.h
index 416d68c9a0..505957f6fb 100644
--- a/app/test/test_ring_stress.h
+++ b/app/test/test_ring_stress.h
@@ -34,6 +34,7 @@ struct test {
extern const struct test test_ring_mpmc_stress;
extern const struct test test_ring_rts_stress;
+extern const struct test test_ring_rts_v2_stress;
extern const struct test test_ring_hts_stress;
extern const struct test test_ring_mt_peek_stress;
extern const struct test test_ring_mt_peek_stress_zc;
diff --git a/devtools/libabigail.abignore b/devtools/libabigail.abignore
index 21b8cd6113..d4dd99a99e 100644
--- a/devtools/libabigail.abignore
+++ b/devtools/libabigail.abignore
@@ -33,3 +33,9 @@
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; Temporary exceptions till next major ABI version ;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+[suppress_type]
+ type_kind = struct
+ name = rte_ring_rts_cache
+[suppress_type]
+ name = rte_ring_rts_headtail
+ has_data_member_inserted_between = {offset_of(head), end}
diff --git a/doc/guides/rel_notes/release_25_03.rst b/doc/guides/rel_notes/release_25_03.rst
index 426dfcd982..f73bc9e397 100644
--- a/doc/guides/rel_notes/release_25_03.rst
+++ b/doc/guides/rel_notes/release_25_03.rst
@@ -102,6 +102,8 @@ ABI Changes
* No ABI change that would break compatibility with 24.11.
+* ring: Added ``rte_ring_rts_cache`` structure and ``rts_cache`` field to the
+ ``rte_ring_rts_headtail`` structure.
Known Issues
------------
diff --git a/lib/ring/rte_ring.c b/lib/ring/rte_ring.c
index aebb6d6728..ada1ae88fa 100644
--- a/lib/ring/rte_ring.c
+++ b/lib/ring/rte_ring.c
@@ -43,7 +43,8 @@ EAL_REGISTER_TAILQ(rte_ring_tailq)
/* mask of all valid flag values to ring_create() */
#define RING_F_MASK (RING_F_SP_ENQ | RING_F_SC_DEQ | RING_F_EXACT_SZ | \
RING_F_MP_RTS_ENQ | RING_F_MC_RTS_DEQ | \
- RING_F_MP_HTS_ENQ | RING_F_MC_HTS_DEQ)
+ RING_F_MP_HTS_ENQ | RING_F_MC_HTS_DEQ | \
+ RING_F_MP_RTS_V2_ENQ | RING_F_MC_RTS_V2_DEQ)
/* true if x is a power of 2 */
#define POWEROF2(x) ((((x)-1) & (x)) == 0)
@@ -106,6 +107,7 @@ reset_headtail(void *p)
ht->tail = 0;
break;
case RTE_RING_SYNC_MT_RTS:
+ case RTE_RING_SYNC_MT_RTS_V2:
ht_rts->head.raw = 0;
ht_rts->tail.raw = 0;
break;
@@ -135,9 +137,11 @@ get_sync_type(uint32_t flags, enum rte_ring_sync_type *prod_st,
enum rte_ring_sync_type *cons_st)
{
static const uint32_t prod_st_flags =
- (RING_F_SP_ENQ | RING_F_MP_RTS_ENQ | RING_F_MP_HTS_ENQ);
+ (RING_F_SP_ENQ | RING_F_MP_RTS_ENQ | RING_F_MP_HTS_ENQ |
+ RING_F_MP_RTS_V2_ENQ);
static const uint32_t cons_st_flags =
- (RING_F_SC_DEQ | RING_F_MC_RTS_DEQ | RING_F_MC_HTS_DEQ);
+ (RING_F_SC_DEQ | RING_F_MC_RTS_DEQ | RING_F_MC_HTS_DEQ |
+ RING_F_MC_RTS_V2_DEQ);
switch (flags & prod_st_flags) {
case 0:
@@ -152,6 +156,9 @@ get_sync_type(uint32_t flags, enum rte_ring_sync_type *prod_st,
case RING_F_MP_HTS_ENQ:
*prod_st = RTE_RING_SYNC_MT_HTS;
break;
+ case RING_F_MP_RTS_V2_ENQ:
+ *prod_st = RTE_RING_SYNC_MT_RTS_V2;
+ break;
default:
return -EINVAL;
}
@@ -169,6 +176,9 @@ get_sync_type(uint32_t flags, enum rte_ring_sync_type *prod_st,
case RING_F_MC_HTS_DEQ:
*cons_st = RTE_RING_SYNC_MT_HTS;
break;
+ case RING_F_MC_RTS_V2_DEQ:
+ *cons_st = RTE_RING_SYNC_MT_RTS_V2;
+ break;
default:
return -EINVAL;
}
@@ -239,6 +249,28 @@ rte_ring_init(struct rte_ring *r, const char *name, unsigned int count,
if (flags & RING_F_MC_RTS_DEQ)
rte_ring_set_cons_htd_max(r, r->capacity / HTD_MAX_DEF);
+ /* set default values for head-tail distance and allocate memory to cache */
+ if (flags & RING_F_MP_RTS_V2_ENQ) {
+ rte_ring_set_prod_htd_max(r, r->capacity / HTD_MAX_DEF);
+ r->rts_prod.rts_cache = (struct rte_ring_rts_cache *)rte_zmalloc(
+ "RTS_PROD_CACHE", sizeof(struct rte_ring_rts_cache) * r->size, 0);
+ if (r->rts_prod.rts_cache == NULL) {
+ RING_LOG(ERR, "Cannot reserve memory for rts prod cache");
+ return -ENOMEM;
+ }
+ }
+ if (flags & RING_F_MC_RTS_V2_DEQ) {
+ rte_ring_set_cons_htd_max(r, r->capacity / HTD_MAX_DEF);
+ r->rts_cons.rts_cache = (struct rte_ring_rts_cache *)rte_zmalloc(
+ "RTS_CONS_CACHE", sizeof(struct rte_ring_rts_cache) * r->size, 0);
+ if (r->rts_cons.rts_cache == NULL) {
+ if (flags & RING_F_MP_RTS_V2_ENQ)
+ rte_free(r->rts_prod.rts_cache);
+ RING_LOG(ERR, "Cannot reserve memory for rts cons cache");
+ return -ENOMEM;
+ }
+ }
+
return 0;
}
@@ -293,9 +325,14 @@ rte_ring_create_elem(const char *name, unsigned int esize, unsigned int count,
mz_flags, alignof(typeof(*r)));
if (mz != NULL) {
r = mz->addr;
- /* no need to check return value here, we already checked the
- * arguments above */
- rte_ring_init(r, name, requested_count, flags);
+
+ if (rte_ring_init(r, name, requested_count, flags)) {
+ rte_free(te);
+ if (rte_memzone_free(mz) != 0)
+ RING_LOG(ERR, "Cannot free memory for ring");
+ rte_mcfg_tailq_write_unlock();
+ return NULL;
+ }
te->data = (void *) r;
r->memzone = mz;
@@ -358,6 +395,11 @@ rte_ring_free(struct rte_ring *r)
rte_mcfg_tailq_write_unlock();
+ if (r->flags & RING_F_MP_RTS_V2_ENQ)
+ rte_free(r->rts_prod.rts_cache);
+ if (r->flags & RING_F_MC_RTS_V2_DEQ)
+ rte_free(r->rts_cons.rts_cache);
+
if (rte_memzone_free(r->memzone) != 0)
RING_LOG(ERR, "Cannot free memory");
diff --git a/lib/ring/rte_ring.h b/lib/ring/rte_ring.h
index 11ca69c73d..2b35ce038e 100644
--- a/lib/ring/rte_ring.h
+++ b/lib/ring/rte_ring.h
@@ -89,6 +89,9 @@ ssize_t rte_ring_get_memsize(unsigned int count);
* - RING_F_MP_RTS_ENQ: If this flag is set, the default behavior when
* using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
* is "multi-producer RTS mode".
+ * - RING_F_MP_RTS_V2_ENQ: If this flag is set, the default behavior when
+ * using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
+ * is "multi-producer RTS V2 mode".
* - RING_F_MP_HTS_ENQ: If this flag is set, the default behavior when
* using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
* is "multi-producer HTS mode".
@@ -101,6 +104,9 @@ ssize_t rte_ring_get_memsize(unsigned int count);
* - RING_F_MC_RTS_DEQ: If this flag is set, the default behavior when
* using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
* is "multi-consumer RTS mode".
+ * - RING_F_MC_RTS_V2_DEQ: If this flag is set, the default behavior when
+ * using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
+ * is "multi-consumer RTS V2 mode".
* - RING_F_MC_HTS_DEQ: If this flag is set, the default behavior when
* using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
* is "multi-consumer HTS mode".
@@ -149,6 +155,9 @@ int rte_ring_init(struct rte_ring *r, const char *name, unsigned int count,
* - RING_F_MP_RTS_ENQ: If this flag is set, the default behavior when
* using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
* is "multi-producer RTS mode".
+ * - RING_F_MP_RTS_V2_ENQ: If this flag is set, the default behavior when
+ * using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
+ * is "multi-producer RTS V2 mode".
* - RING_F_MP_HTS_ENQ: If this flag is set, the default behavior when
* using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
* is "multi-producer HTS mode".
@@ -161,6 +170,9 @@ int rte_ring_init(struct rte_ring *r, const char *name, unsigned int count,
* - RING_F_MC_RTS_DEQ: If this flag is set, the default behavior when
* using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
* is "multi-consumer RTS mode".
+ * - RING_F_MC_RTS_V2_DEQ: If this flag is set, the default behavior when
+ * using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
+ * is "multi-consumer RTS V2 mode".
* - RING_F_MC_HTS_DEQ: If this flag is set, the default behavior when
* using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
* is "multi-consumer HTS mode".
diff --git a/lib/ring/rte_ring_core.h b/lib/ring/rte_ring_core.h
index 6cd6ce9884..9e627d26c1 100644
--- a/lib/ring/rte_ring_core.h
+++ b/lib/ring/rte_ring_core.h
@@ -55,6 +55,7 @@ enum rte_ring_sync_type {
RTE_RING_SYNC_ST, /**< single thread only */
RTE_RING_SYNC_MT_RTS, /**< multi-thread relaxed tail sync */
RTE_RING_SYNC_MT_HTS, /**< multi-thread head/tail sync */
+ RTE_RING_SYNC_MT_RTS_V2, /**< multi-thread relaxed tail sync v2 */
};
/**
@@ -82,11 +83,16 @@ union __rte_ring_rts_poscnt {
} val;
};
+struct rte_ring_rts_cache {
+ volatile RTE_ATOMIC(uint32_t) num; /**< Number of objs. */
+};
+
struct rte_ring_rts_headtail {
volatile union __rte_ring_rts_poscnt tail;
enum rte_ring_sync_type sync_type; /**< sync type of prod/cons */
uint32_t htd_max; /**< max allowed distance between head/tail */
volatile union __rte_ring_rts_poscnt head;
+ struct rte_ring_rts_cache *rts_cache; /**< Cache of prod/cons */
};
union __rte_ring_hts_pos {
@@ -163,4 +169,7 @@ struct rte_ring {
#define RING_F_MP_HTS_ENQ 0x0020 /**< The default enqueue is "MP HTS". */
#define RING_F_MC_HTS_DEQ 0x0040 /**< The default dequeue is "MC HTS". */
+#define RING_F_MP_RTS_V2_ENQ 0x0080 /**< The default enqueue is "MP RTS V2". */
+#define RING_F_MC_RTS_V2_DEQ 0x0100 /**< The default dequeue is "MC RTS V2". */
+
#endif /* _RTE_RING_CORE_H_ */
diff --git a/lib/ring/rte_ring_elem.h b/lib/ring/rte_ring_elem.h
index b96bfc003f..1352709f94 100644
--- a/lib/ring/rte_ring_elem.h
+++ b/lib/ring/rte_ring_elem.h
@@ -71,6 +71,9 @@ ssize_t rte_ring_get_memsize_elem(unsigned int esize, unsigned int count);
* - RING_F_MP_RTS_ENQ: If this flag is set, the default behavior when
* using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
* is "multi-producer RTS mode".
+ * - RING_F_MP_RTS_V2_ENQ: If this flag is set, the default behavior when
+ * using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
+ * is "multi-producer RTS V2 mode".
* - RING_F_MP_HTS_ENQ: If this flag is set, the default behavior when
* using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
* is "multi-producer HTS mode".
@@ -83,6 +86,9 @@ ssize_t rte_ring_get_memsize_elem(unsigned int esize, unsigned int count);
* - RING_F_MC_RTS_DEQ: If this flag is set, the default behavior when
* using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
* is "multi-consumer RTS mode".
+ * - RING_F_MC_RTS_V2_DEQ: If this flag is set, the default behavior when
+ * using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
+ * is "multi-consumer RTS V2 mode".
* - RING_F_MC_HTS_DEQ: If this flag is set, the default behavior when
* using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
* is "multi-consumer HTS mode".
@@ -203,6 +209,9 @@ rte_ring_enqueue_bulk_elem(struct rte_ring *r, const void *obj_table,
case RTE_RING_SYNC_MT_HTS:
return rte_ring_mp_hts_enqueue_bulk_elem(r, obj_table, esize, n,
free_space);
+ case RTE_RING_SYNC_MT_RTS_V2:
+ return rte_ring_mp_rts_v2_enqueue_bulk_elem(r, obj_table, esize, n,
+ free_space);
}
/* valid ring should never reach this point */
@@ -385,6 +394,9 @@ rte_ring_dequeue_bulk_elem(struct rte_ring *r, void *obj_table,
case RTE_RING_SYNC_MT_HTS:
return rte_ring_mc_hts_dequeue_bulk_elem(r, obj_table, esize,
n, available);
+ case RTE_RING_SYNC_MT_RTS_V2:
+ return rte_ring_mc_rts_v2_dequeue_bulk_elem(r, obj_table, esize,
+ n, available);
}
/* valid ring should never reach this point */
@@ -571,6 +583,9 @@ rte_ring_enqueue_burst_elem(struct rte_ring *r, const void *obj_table,
case RTE_RING_SYNC_MT_HTS:
return rte_ring_mp_hts_enqueue_burst_elem(r, obj_table, esize,
n, free_space);
+ case RTE_RING_SYNC_MT_RTS_V2:
+ return rte_ring_mp_rts_v2_enqueue_burst_elem(r, obj_table, esize,
+ n, free_space);
}
/* valid ring should never reach this point */
@@ -681,6 +696,9 @@ rte_ring_dequeue_burst_elem(struct rte_ring *r, void *obj_table,
case RTE_RING_SYNC_MT_HTS:
return rte_ring_mc_hts_dequeue_burst_elem(r, obj_table, esize,
n, available);
+ case RTE_RING_SYNC_MT_RTS_V2:
+ return rte_ring_mc_rts_v2_dequeue_burst_elem(r, obj_table, esize,
+ n, available);
}
/* valid ring should never reach this point */
diff --git a/lib/ring/rte_ring_rts.h b/lib/ring/rte_ring_rts.h
index d7a3863c83..b47e400452 100644
--- a/lib/ring/rte_ring_rts.h
+++ b/lib/ring/rte_ring_rts.h
@@ -84,6 +84,33 @@ rte_ring_mp_rts_enqueue_bulk_elem(struct rte_ring *r, const void *obj_table,
RTE_RING_QUEUE_FIXED, free_space);
}
+/**
+ * Enqueue several objects on the RTS ring (multi-producers safe).
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of objects.
+ * @param esize
+ * The size of ring element, in bytes. It must be a multiple of 4.
+ * This must be the same value used while creating the ring. Otherwise
+ * the results are undefined.
+ * @param n
+ * The number of objects to add in the ring from the obj_table.
+ * @param free_space
+ * if non-NULL, returns the amount of space in the ring after the
+ * enqueue operation has finished.
+ * @return
+ * The number of objects enqueued, either 0 or n
+ */
+static __rte_always_inline unsigned int
+rte_ring_mp_rts_v2_enqueue_bulk_elem(struct rte_ring *r, const void *obj_table,
+ unsigned int esize, unsigned int n, unsigned int *free_space)
+{
+ return __rte_ring_do_rts_v2_enqueue_elem(r, obj_table, esize, n,
+ RTE_RING_QUEUE_FIXED, free_space);
+}
+
/**
* Dequeue several objects from an RTS ring (multi-consumers safe).
*
@@ -111,6 +138,33 @@ rte_ring_mc_rts_dequeue_bulk_elem(struct rte_ring *r, void *obj_table,
RTE_RING_QUEUE_FIXED, available);
}
+/**
+ * Dequeue several objects from an RTS ring (multi-consumers safe).
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of objects that will be filled.
+ * @param esize
+ * The size of ring element, in bytes. It must be a multiple of 4.
+ * This must be the same value used while creating the ring. Otherwise
+ * the results are undefined.
+ * @param n
+ * The number of objects to dequeue from the ring to the obj_table.
+ * @param available
+ * If non-NULL, returns the number of remaining ring entries after the
+ * dequeue has finished.
+ * @return
+ * The number of objects dequeued, either 0 or n
+ */
+static __rte_always_inline unsigned int
+rte_ring_mc_rts_v2_dequeue_bulk_elem(struct rte_ring *r, void *obj_table,
+ unsigned int esize, unsigned int n, unsigned int *available)
+{
+ return __rte_ring_do_rts_v2_dequeue_elem(r, obj_table, esize, n,
+ RTE_RING_QUEUE_FIXED, available);
+}
+
/**
* Enqueue several objects on the RTS ring (multi-producers safe).
*
@@ -138,6 +192,33 @@ rte_ring_mp_rts_enqueue_burst_elem(struct rte_ring *r, const void *obj_table,
RTE_RING_QUEUE_VARIABLE, free_space);
}
+/**
+ * Enqueue several objects on the RTS ring (multi-producers safe).
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of objects.
+ * @param esize
+ * The size of ring element, in bytes. It must be a multiple of 4.
+ * This must be the same value used while creating the ring. Otherwise
+ * the results are undefined.
+ * @param n
+ * The number of objects to add in the ring from the obj_table.
+ * @param free_space
+ * if non-NULL, returns the amount of space in the ring after the
+ * enqueue operation has finished.
+ * @return
+ * - n: Actual number of objects enqueued.
+ */
+static __rte_always_inline unsigned int
+rte_ring_mp_rts_v2_enqueue_burst_elem(struct rte_ring *r, const void *obj_table,
+ unsigned int esize, unsigned int n, unsigned int *free_space)
+{
+ return __rte_ring_do_rts_v2_enqueue_elem(r, obj_table, esize, n,
+ RTE_RING_QUEUE_VARIABLE, free_space);
+}
+
/**
* Dequeue several objects from an RTS ring (multi-consumers safe).
* When the requested objects are more than the available objects,
@@ -167,6 +248,35 @@ rte_ring_mc_rts_dequeue_burst_elem(struct rte_ring *r, void *obj_table,
RTE_RING_QUEUE_VARIABLE, available);
}
+/**
+ * Dequeue several objects from an RTS ring (multi-consumers safe).
+ * When the requested objects are more than the available objects,
+ * only dequeue the actual number of objects.
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of objects that will be filled.
+ * @param esize
+ * The size of ring element, in bytes. It must be a multiple of 4.
+ * This must be the same value used while creating the ring. Otherwise
+ * the results are undefined.
+ * @param n
+ * The number of objects to dequeue from the ring to the obj_table.
+ * @param available
+ * If non-NULL, returns the number of remaining ring entries after the
+ * dequeue has finished.
+ * @return
+ * - n: Actual number of objects dequeued, 0 if ring is empty
+ */
+static __rte_always_inline unsigned int
+rte_ring_mc_rts_v2_dequeue_burst_elem(struct rte_ring *r, void *obj_table,
+ unsigned int esize, unsigned int n, unsigned int *available)
+{
+ return __rte_ring_do_rts_v2_dequeue_elem(r, obj_table, esize, n,
+ RTE_RING_QUEUE_VARIABLE, available);
+}
+
/**
* Enqueue several objects on the RTS ring (multi-producers safe).
*
@@ -213,6 +323,52 @@ rte_ring_mc_rts_dequeue_bulk(struct rte_ring *r, void **obj_table,
sizeof(uintptr_t), n, available);
}
+/**
+ * Enqueue several objects on the RTS V2 ring (multi-producers safe).
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of void * pointers (objects).
+ * @param n
+ * The number of objects to add in the ring from the obj_table.
+ * @param free_space
+ * if non-NULL, returns the amount of space in the ring after the
+ * enqueue operation has finished.
+ * @return
+ * The number of objects enqueued, either 0 or n
+ */
+static __rte_always_inline unsigned int
+rte_ring_mp_rts_v2_enqueue_bulk(struct rte_ring *r, void * const *obj_table,
+ unsigned int n, unsigned int *free_space)
+{
+ return rte_ring_mp_rts_v2_enqueue_bulk_elem(r, obj_table,
+ sizeof(uintptr_t), n, free_space);
+}
+
+/**
+ * Dequeue several objects from an RTS V2 ring (multi-consumers safe).
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of void * pointers (objects) that will be filled.
+ * @param n
+ * The number of objects to dequeue from the ring to the obj_table.
+ * @param available
+ * If non-NULL, returns the number of remaining ring entries after the
+ * dequeue has finished.
+ * @return
+ * The number of objects dequeued, either 0 or n
+ */
+static __rte_always_inline unsigned int
+rte_ring_mc_rts_v2_dequeue_bulk(struct rte_ring *r, void **obj_table,
+ unsigned int n, unsigned int *available)
+{
+ return rte_ring_mc_rts_v2_dequeue_bulk_elem(r, obj_table,
+ sizeof(uintptr_t), n, available);
+}
+
/**
* Enqueue several objects on the RTS ring (multi-producers safe).
*
@@ -261,6 +417,54 @@ rte_ring_mc_rts_dequeue_burst(struct rte_ring *r, void **obj_table,
sizeof(uintptr_t), n, available);
}
+/**
+ * Enqueue several objects on the RTS V2 ring (multi-producers safe).
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of void * pointers (objects).
+ * @param n
+ * The number of objects to add in the ring from the obj_table.
+ * @param free_space
+ * if non-NULL, returns the amount of space in the ring after the
+ * enqueue operation has finished.
+ * @return
+ * - n: Actual number of objects enqueued.
+ */
+static __rte_always_inline unsigned int
+rte_ring_mp_rts_v2_enqueue_burst(struct rte_ring *r, void * const *obj_table,
+ unsigned int n, unsigned int *free_space)
+{
+ return rte_ring_mp_rts_v2_enqueue_burst_elem(r, obj_table,
+ sizeof(uintptr_t), n, free_space);
+}
+
+/**
+ * Dequeue several objects from an RTS V2 ring (multi-consumers safe).
+ * When the requested objects are more than the available objects,
+ * only dequeue the actual number of objects.
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of void * pointers (objects) that will be filled.
+ * @param n
+ * The number of objects to dequeue from the ring to the obj_table.
+ * @param available
+ * If non-NULL, returns the number of remaining ring entries after the
+ * dequeue has finished.
+ * @return
+ * - n: Actual number of objects dequeued, 0 if ring is empty
+ */
+static __rte_always_inline unsigned int
+rte_ring_mc_rts_v2_dequeue_burst(struct rte_ring *r, void **obj_table,
+ unsigned int n, unsigned int *available)
+{
+ return rte_ring_mc_rts_v2_dequeue_burst_elem(r, obj_table,
+ sizeof(uintptr_t), n, available);
+}
+
/**
* Return producer max Head-Tail-Distance (HTD).
*
@@ -273,7 +477,8 @@ rte_ring_mc_rts_dequeue_burst(struct rte_ring *r, void **obj_table,
static inline uint32_t
rte_ring_get_prod_htd_max(const struct rte_ring *r)
{
- if (r->prod.sync_type == RTE_RING_SYNC_MT_RTS)
+ if ((r->prod.sync_type == RTE_RING_SYNC_MT_RTS) ||
+ (r->prod.sync_type == RTE_RING_SYNC_MT_RTS_V2))
return r->rts_prod.htd_max;
return UINT32_MAX;
}
@@ -292,7 +497,8 @@ rte_ring_get_prod_htd_max(const struct rte_ring *r)
static inline int
rte_ring_set_prod_htd_max(struct rte_ring *r, uint32_t v)
{
- if (r->prod.sync_type != RTE_RING_SYNC_MT_RTS)
+ if ((r->prod.sync_type != RTE_RING_SYNC_MT_RTS) &&
+ (r->prod.sync_type != RTE_RING_SYNC_MT_RTS_V2))
return -ENOTSUP;
r->rts_prod.htd_max = v;
@@ -311,7 +517,8 @@ rte_ring_set_prod_htd_max(struct rte_ring *r, uint32_t v)
static inline uint32_t
rte_ring_get_cons_htd_max(const struct rte_ring *r)
{
- if (r->cons.sync_type == RTE_RING_SYNC_MT_RTS)
+ if ((r->cons.sync_type == RTE_RING_SYNC_MT_RTS) ||
+ (r->cons.sync_type == RTE_RING_SYNC_MT_RTS_V2))
return r->rts_cons.htd_max;
return UINT32_MAX;
}
@@ -330,7 +537,8 @@ rte_ring_get_cons_htd_max(const struct rte_ring *r)
static inline int
rte_ring_set_cons_htd_max(struct rte_ring *r, uint32_t v)
{
- if (r->cons.sync_type != RTE_RING_SYNC_MT_RTS)
+ if ((r->cons.sync_type != RTE_RING_SYNC_MT_RTS) &&
+ (r->cons.sync_type != RTE_RING_SYNC_MT_RTS_V2))
return -ENOTSUP;
r->rts_cons.htd_max = v;
diff --git a/lib/ring/rte_ring_rts_elem_pvt.h b/lib/ring/rte_ring_rts_elem_pvt.h
index 122650346b..4ce22a93ed 100644
--- a/lib/ring/rte_ring_rts_elem_pvt.h
+++ b/lib/ring/rte_ring_rts_elem_pvt.h
@@ -46,6 +46,92 @@ __rte_ring_rts_update_tail(struct rte_ring_rts_headtail *ht)
rte_memory_order_release, rte_memory_order_acquire) == 0);
}
+/**
+ * @file rte_ring_rts_elem_pvt.h
+ * It is not recommended to include this file directly,
+ * include <rte_ring.h> instead.
+ * Contains internal helper functions for Relaxed Tail Sync (RTS) ring mode.
+ * For more information please refer to <rte_ring_rts.h>.
+ */
+
+/**
+ * @internal This function updates tail values.
+ */
+static __rte_always_inline void
+__rte_ring_rts_v2_update_tail(struct rte_ring_rts_headtail *ht,
+ uint32_t old_tail, uint32_t num, uint32_t mask)
+{
+ union __rte_ring_rts_poscnt ot, nt;
+
+ ot.val.cnt = nt.val.cnt = 0;
+ ot.val.pos = old_tail;
+ nt.val.pos = old_tail + num;
+
+ /*
+ * If the tail is equal to the current enqueues/dequeues, update
+ * the tail with new value and then continue to try to update the
+ * tail until the num of the cache is 0, otherwise write the num of
+ * the current enqueues/dequeues to the cache.
+ */
+
+ if (rte_atomic_compare_exchange_strong_explicit(&ht->tail.raw,
+ (uint64_t *)(uintptr_t)&ot.raw, nt.raw,
+ rte_memory_order_release, rte_memory_order_acquire) == 0) {
+ ot.val.pos = old_tail;
+
+ /*
+ * Write the num of the current enqueues/dequeues to the
+ * corresponding cache.
+ */
+ rte_atomic_store_explicit(&ht->rts_cache[ot.val.pos & mask].num,
+ num, rte_memory_order_release);
+
+ /*
+ * There may be competition with another enqueues/dequeues
+ * for the update tail. The winner continues to try to update
+ * the tail, and the loser exits.
+ */
+ if (rte_atomic_compare_exchange_strong_explicit(&ht->tail.raw,
+ (uint64_t *)(uintptr_t)&ot.raw, nt.raw,
+ rte_memory_order_release, rte_memory_order_acquire) == 0)
+ return;
+
+ /*
+ * Set the corresponding cache to 0 for next use.
+ */
+ rte_atomic_store_explicit(&ht->rts_cache[ot.val.pos & mask].num,
+ 0, rte_memory_order_release);
+ }
+
+ /*
+ * Try to update the tail until the num of the corresponding cache is 0.
+ * Getting here means that the current enqueues/dequeues is trying to update
+ * the tail of another enqueues/dequeues.
+ */
+ while (1) {
+ num = rte_atomic_load_explicit(&ht->rts_cache[nt.val.pos & mask].num,
+ rte_memory_order_acquire);
+ if (num == 0)
+ break;
+
+ ot.val.pos = nt.val.pos;
+ nt.val.pos += num;
+
+ /*
+ * There may be competition with another enqueues/dequeues
+ * for the update tail. The winner continues to try to update
+ * the tail, and the loser exits.
+ */
+ if (rte_atomic_compare_exchange_strong_explicit(&ht->tail.raw,
+ (uint64_t *)(uintptr_t)&ot.raw, nt.raw,
+ rte_memory_order_release, rte_memory_order_acquire) == 0)
+ return;
+
+ rte_atomic_store_explicit(&ht->rts_cache[ot.val.pos & mask].num,
+ 0, rte_memory_order_release);
+ };
+}
+
/**
* @internal This function waits till head/tail distance wouldn't
* exceed pre-defined max value.
@@ -218,6 +304,47 @@ __rte_ring_do_rts_enqueue_elem(struct rte_ring *r, const void *obj_table,
return n;
}
+/**
+ * @internal Enqueue several objects on the RTS ring.
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of objects.
+ * @param esize
+ * The size of ring element, in bytes. It must be a multiple of 4.
+ * This must be the same value used while creating the ring. Otherwise
+ * the results are undefined.
+ * @param n
+ * The number of objects to add in the ring from the obj_table.
+ * @param behavior
+ * RTE_RING_QUEUE_FIXED: Enqueue a fixed number of items from a ring
+ * RTE_RING_QUEUE_VARIABLE: Enqueue as many items as possible from ring
+ * @param free_space
+ * returns the amount of space after the enqueue operation has finished
+ * @return
+ * Actual number of objects enqueued.
+ * If behavior == RTE_RING_QUEUE_FIXED, this will be 0 or n only.
+ */
+static __rte_always_inline unsigned int
+__rte_ring_do_rts_v2_enqueue_elem(struct rte_ring *r, const void *obj_table,
+ uint32_t esize, uint32_t n, enum rte_ring_queue_behavior behavior,
+ uint32_t *free_space)
+{
+ uint32_t free, head;
+
+ n = __rte_ring_rts_move_prod_head(r, n, behavior, &head, &free);
+
+ if (n != 0) {
+ __rte_ring_enqueue_elems(r, head, obj_table, esize, n);
+ __rte_ring_rts_v2_update_tail(&r->rts_prod, head, n, r->mask);
+ }
+
+ if (free_space != NULL)
+ *free_space = free - n;
+ return n;
+}
+
/**
* @internal Dequeue several objects from the RTS ring.
*
@@ -259,4 +386,45 @@ __rte_ring_do_rts_dequeue_elem(struct rte_ring *r, void *obj_table,
return n;
}
+/**
+ * @internal Dequeue several objects from the RTS ring.
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of objects.
+ * @param esize
+ * The size of ring element, in bytes. It must be a multiple of 4.
+ * This must be the same value used while creating the ring. Otherwise
+ * the results are undefined.
+ * @param n
+ * The number of objects to pull from the ring.
+ * @param behavior
+ * RTE_RING_QUEUE_FIXED: Dequeue a fixed number of items from a ring
+ * RTE_RING_QUEUE_VARIABLE: Dequeue as many items as possible from ring
+ * @param available
+ * returns the number of remaining ring entries after the dequeue has finished
+ * @return
+ * - Actual number of objects dequeued.
+ * If behavior == RTE_RING_QUEUE_FIXED, this will be 0 or n only.
+ */
+static __rte_always_inline unsigned int
+__rte_ring_do_rts_v2_dequeue_elem(struct rte_ring *r, void *obj_table,
+ uint32_t esize, uint32_t n, enum rte_ring_queue_behavior behavior,
+ uint32_t *available)
+{
+ uint32_t entries, head;
+
+ n = __rte_ring_rts_move_cons_head(r, n, behavior, &head, &entries);
+
+ if (n != 0) {
+ __rte_ring_dequeue_elems(r, head, obj_table, esize, n);
+ __rte_ring_rts_v2_update_tail(&r->rts_cons, head, n, r->mask);
+ }
+
+ if (available != NULL)
+ *available = entries - n;
+ return n;
+}
+
#endif /* _RTE_RING_RTS_ELEM_PVT_H_ */
--
2.27.0
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH] ring: add the second version of the RTS interface
@ 2025-01-05 9:57 Huichao Cai
2025-01-05 15:13 ` [PATCH v2] " Huichao Cai
0 siblings, 1 reply; 4+ messages in thread
From: Huichao Cai @ 2025-01-05 9:57 UTC (permalink / raw)
To: honnappa.nagarahalli, konstantin.v.ananyev; +Cc: dev
The timing of the update of the RTS enqueues/dequeues tail is
limited to the last enqueues/dequeues, which reduces concurrency,
so the RTS interface of the V2 version is added, which makes the tail
of the enqueues/dequeues not limited to the last enqueues/dequeues
and thus enables timely updates to increase concurrency.
Add some corresponding test cases.
Signed-off-by: Huichao Cai <chcchc88@163.com>
---
app/test/meson.build | 1 +
app/test/test_ring.c | 26 +++
app/test/test_ring_rts_v2_stress.c | 32 ++++
app/test/test_ring_stress.c | 3 +
app/test/test_ring_stress.h | 1 +
devtools/libabigail.abignore | 3 +
doc/guides/rel_notes/release_25_03.rst | 2 +
lib/ring/rte_ring.c | 53 +++++-
lib/ring/rte_ring.h | 12 ++
lib/ring/rte_ring_core.h | 9 ++
lib/ring/rte_ring_elem.h | 18 +++
lib/ring/rte_ring_rts.h | 216 ++++++++++++++++++++++++-
lib/ring/rte_ring_rts_elem_pvt.h | 168 +++++++++++++++++++
13 files changed, 534 insertions(+), 10 deletions(-)
create mode 100644 app/test/test_ring_rts_v2_stress.c
diff --git a/app/test/meson.build b/app/test/meson.build
index d5cb6a7f7a..e3d8cef3fa 100644
--- a/app/test/meson.build
+++ b/app/test/meson.build
@@ -166,6 +166,7 @@ source_file_deps = {
'test_ring_mt_peek_stress_zc.c': ['ptr_compress'],
'test_ring_perf.c': ['ptr_compress'],
'test_ring_rts_stress.c': ['ptr_compress'],
+ 'test_ring_rts_v2_stress.c': ['ptr_compress'],
'test_ring_st_peek_stress.c': ['ptr_compress'],
'test_ring_st_peek_stress_zc.c': ['ptr_compress'],
'test_ring_stress.c': ['ptr_compress'],
diff --git a/app/test/test_ring.c b/app/test/test_ring.c
index ba1fec1de3..094f14b859 100644
--- a/app/test/test_ring.c
+++ b/app/test/test_ring.c
@@ -284,6 +284,19 @@ static const struct {
.felem = rte_ring_dequeue_bulk_elem,
},
},
+ {
+ .desc = "MP_RTS/MC_RTS V2 sync mode",
+ .api_type = TEST_RING_ELEM_BULK | TEST_RING_THREAD_DEF,
+ .create_flags = RING_F_MP_RTS_V2_ENQ | RING_F_MC_RTS_V2_DEQ,
+ .enq = {
+ .flegacy = rte_ring_enqueue_bulk,
+ .felem = rte_ring_enqueue_bulk_elem,
+ },
+ .deq = {
+ .flegacy = rte_ring_dequeue_bulk,
+ .felem = rte_ring_dequeue_bulk_elem,
+ },
+ },
{
.desc = "MP_HTS/MC_HTS sync mode",
.api_type = TEST_RING_ELEM_BULK | TEST_RING_THREAD_DEF,
@@ -349,6 +362,19 @@ static const struct {
.felem = rte_ring_dequeue_burst_elem,
},
},
+ {
+ .desc = "MP_RTS/MC_RTS V2 sync mode",
+ .api_type = TEST_RING_ELEM_BURST | TEST_RING_THREAD_DEF,
+ .create_flags = RING_F_MP_RTS_V2_ENQ | RING_F_MC_RTS_V2_DEQ,
+ .enq = {
+ .flegacy = rte_ring_enqueue_burst,
+ .felem = rte_ring_enqueue_burst_elem,
+ },
+ .deq = {
+ .flegacy = rte_ring_dequeue_burst,
+ .felem = rte_ring_dequeue_burst_elem,
+ },
+ },
{
.desc = "MP_HTS/MC_HTS sync mode",
.api_type = TEST_RING_ELEM_BURST | TEST_RING_THREAD_DEF,
diff --git a/app/test/test_ring_rts_v2_stress.c b/app/test/test_ring_rts_v2_stress.c
new file mode 100644
index 0000000000..6079366a7d
--- /dev/null
+++ b/app/test/test_ring_rts_v2_stress.c
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2020 Intel Corporation
+ */
+
+#include "test_ring_stress_impl.h"
+
+static inline uint32_t
+_st_ring_dequeue_bulk(struct rte_ring *r, void **obj, uint32_t n,
+ uint32_t *avail)
+{
+ return rte_ring_mc_rts_v2_dequeue_bulk(r, obj, n, avail);
+}
+
+static inline uint32_t
+_st_ring_enqueue_bulk(struct rte_ring *r, void * const *obj, uint32_t n,
+ uint32_t *free)
+{
+ return rte_ring_mp_rts_v2_enqueue_bulk(r, obj, n, free);
+}
+
+static int
+_st_ring_init(struct rte_ring *r, const char *name, uint32_t num)
+{
+ return rte_ring_init(r, name, num,
+ RING_F_MP_RTS_V2_ENQ | RING_F_MC_RTS_V2_DEQ);
+}
+
+const struct test test_ring_rts_v2_stress = {
+ .name = "MT_RTS_V2",
+ .nb_case = RTE_DIM(tests),
+ .cases = tests,
+};
diff --git a/app/test/test_ring_stress.c b/app/test/test_ring_stress.c
index 1af45e0fc8..94085acd5e 100644
--- a/app/test/test_ring_stress.c
+++ b/app/test/test_ring_stress.c
@@ -43,6 +43,9 @@ test_ring_stress(void)
n += test_ring_rts_stress.nb_case;
k += run_test(&test_ring_rts_stress);
+ n += test_ring_rts_v2_stress.nb_case;
+ k += run_test(&test_ring_rts_v2_stress);
+
n += test_ring_hts_stress.nb_case;
k += run_test(&test_ring_hts_stress);
diff --git a/app/test/test_ring_stress.h b/app/test/test_ring_stress.h
index 416d68c9a0..505957f6fb 100644
--- a/app/test/test_ring_stress.h
+++ b/app/test/test_ring_stress.h
@@ -34,6 +34,7 @@ struct test {
extern const struct test test_ring_mpmc_stress;
extern const struct test test_ring_rts_stress;
+extern const struct test test_ring_rts_v2_stress;
extern const struct test test_ring_hts_stress;
extern const struct test test_ring_mt_peek_stress;
extern const struct test test_ring_mt_peek_stress_zc;
diff --git a/devtools/libabigail.abignore b/devtools/libabigail.abignore
index 21b8cd6113..0a0f305acb 100644
--- a/devtools/libabigail.abignore
+++ b/devtools/libabigail.abignore
@@ -33,3 +33,6 @@
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; Temporary exceptions till next major ABI version ;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+[suppress_type]
+ name = rte_ring_rts_headtail
+ has_data_member_inserted_between = {offset_of(head), end}
diff --git a/doc/guides/rel_notes/release_25_03.rst b/doc/guides/rel_notes/release_25_03.rst
index 426dfcd982..f73bc9e397 100644
--- a/doc/guides/rel_notes/release_25_03.rst
+++ b/doc/guides/rel_notes/release_25_03.rst
@@ -102,6 +102,8 @@ ABI Changes
* No ABI change that would break compatibility with 24.11.
+* ring: Added ``rte_ring_rts_cache`` structure and ``rts_cache`` field to the
+ ``rte_ring_rts_headtail`` structure.
Known Issues
------------
diff --git a/lib/ring/rte_ring.c b/lib/ring/rte_ring.c
index aebb6d6728..df84592300 100644
--- a/lib/ring/rte_ring.c
+++ b/lib/ring/rte_ring.c
@@ -43,7 +43,8 @@ EAL_REGISTER_TAILQ(rte_ring_tailq)
/* mask of all valid flag values to ring_create() */
#define RING_F_MASK (RING_F_SP_ENQ | RING_F_SC_DEQ | RING_F_EXACT_SZ | \
RING_F_MP_RTS_ENQ | RING_F_MC_RTS_DEQ | \
- RING_F_MP_HTS_ENQ | RING_F_MC_HTS_DEQ)
+ RING_F_MP_HTS_ENQ | RING_F_MC_HTS_DEQ | \
+ RING_F_MP_RTS_V2_ENQ | RING_F_MC_RTS_V2_DEQ)
/* true if x is a power of 2 */
#define POWEROF2(x) ((((x)-1) & (x)) == 0)
@@ -106,6 +107,7 @@ reset_headtail(void *p)
ht->tail = 0;
break;
case RTE_RING_SYNC_MT_RTS:
+ case RTE_RING_SYNC_MT_RTS_V2:
ht_rts->head.raw = 0;
ht_rts->tail.raw = 0;
break;
@@ -135,9 +137,11 @@ get_sync_type(uint32_t flags, enum rte_ring_sync_type *prod_st,
enum rte_ring_sync_type *cons_st)
{
static const uint32_t prod_st_flags =
- (RING_F_SP_ENQ | RING_F_MP_RTS_ENQ | RING_F_MP_HTS_ENQ);
+ (RING_F_SP_ENQ | RING_F_MP_RTS_ENQ | RING_F_MP_HTS_ENQ |
+ RING_F_MP_RTS_V2_ENQ);
static const uint32_t cons_st_flags =
- (RING_F_SC_DEQ | RING_F_MC_RTS_DEQ | RING_F_MC_HTS_DEQ);
+ (RING_F_SC_DEQ | RING_F_MC_RTS_DEQ | RING_F_MC_HTS_DEQ |
+ RING_F_MC_RTS_V2_DEQ);
switch (flags & prod_st_flags) {
case 0:
@@ -152,6 +156,9 @@ get_sync_type(uint32_t flags, enum rte_ring_sync_type *prod_st,
case RING_F_MP_HTS_ENQ:
*prod_st = RTE_RING_SYNC_MT_HTS;
break;
+ case RING_F_MP_RTS_V2_ENQ:
+ *prod_st = RTE_RING_SYNC_MT_RTS_V2;
+ break;
default:
return -EINVAL;
}
@@ -169,6 +176,9 @@ get_sync_type(uint32_t flags, enum rte_ring_sync_type *prod_st,
case RING_F_MC_HTS_DEQ:
*cons_st = RTE_RING_SYNC_MT_HTS;
break;
+ case RING_F_MC_RTS_V2_DEQ:
+ *cons_st = RTE_RING_SYNC_MT_RTS_V2;
+ break;
default:
return -EINVAL;
}
@@ -239,6 +249,28 @@ rte_ring_init(struct rte_ring *r, const char *name, unsigned int count,
if (flags & RING_F_MC_RTS_DEQ)
rte_ring_set_cons_htd_max(r, r->capacity / HTD_MAX_DEF);
+ /* set default values for head-tail distance and allocate memory to cache */
+ if (flags & RING_F_MP_RTS_V2_ENQ) {
+ rte_ring_set_prod_htd_max(r, r->capacity / HTD_MAX_DEF);
+ r->rts_prod.rts_cache = (struct rte_ring_rts_cache *)rte_zmalloc(
+ "RTS_PROD_CACHE", sizeof(struct rte_ring_rts_cache) * r->size, 0);
+ if (r->rts_prod.rts_cache == NULL) {
+ RING_LOG(ERR, "Cannot reserve memory for rts prod cache");
+ return -ENOMEM;
+ }
+ }
+ if (flags & RING_F_MC_RTS_V2_DEQ) {
+ rte_ring_set_cons_htd_max(r, r->capacity / HTD_MAX_DEF);
+ r->rts_cons.rts_cache = (struct rte_ring_rts_cache *)rte_zmalloc(
+ "RTS_CONS_CACHE", sizeof(struct rte_ring_rts_cache) * r->size, 0);
+ if (r->rts_cons.rts_cache == NULL) {
+ if (flags & RING_F_MP_RTS_V2_ENQ)
+ rte_free(r->rts_prod.rts_cache);
+ RING_LOG(ERR, "Cannot reserve memory for rts cons cache");
+ return -ENOMEM;
+ }
+ }
+
return 0;
}
@@ -293,9 +325,13 @@ rte_ring_create_elem(const char *name, unsigned int esize, unsigned int count,
mz_flags, alignof(typeof(*r)));
if (mz != NULL) {
r = mz->addr;
- /* no need to check return value here, we already checked the
- * arguments above */
- rte_ring_init(r, name, requested_count, flags);
+
+ if (rte_ring_init(r, name, requested_count, flags)) {
+ rte_free(te);
+ if (rte_memzone_free(mz) != 0)
+ RING_LOG(ERR, "Cannot free memory for ring");
+ return NULL;
+ }
te->data = (void *) r;
r->memzone = mz;
@@ -358,6 +394,11 @@ rte_ring_free(struct rte_ring *r)
rte_mcfg_tailq_write_unlock();
+ if (r->flags & RING_F_MP_RTS_V2_ENQ)
+ rte_free(r->rts_prod.rts_cache);
+ if (r->flags & RING_F_MC_RTS_V2_DEQ)
+ rte_free(r->rts_cons.rts_cache);
+
if (rte_memzone_free(r->memzone) != 0)
RING_LOG(ERR, "Cannot free memory");
diff --git a/lib/ring/rte_ring.h b/lib/ring/rte_ring.h
index 11ca69c73d..2b35ce038e 100644
--- a/lib/ring/rte_ring.h
+++ b/lib/ring/rte_ring.h
@@ -89,6 +89,9 @@ ssize_t rte_ring_get_memsize(unsigned int count);
* - RING_F_MP_RTS_ENQ: If this flag is set, the default behavior when
* using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
* is "multi-producer RTS mode".
+ * - RING_F_MP_RTS_V2_ENQ: If this flag is set, the default behavior when
+ * using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
+ * is "multi-producer RTS V2 mode".
* - RING_F_MP_HTS_ENQ: If this flag is set, the default behavior when
* using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
* is "multi-producer HTS mode".
@@ -101,6 +104,9 @@ ssize_t rte_ring_get_memsize(unsigned int count);
* - RING_F_MC_RTS_DEQ: If this flag is set, the default behavior when
* using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
* is "multi-consumer RTS mode".
+ * - RING_F_MC_RTS_V2_DEQ: If this flag is set, the default behavior when
+ * using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
+ * is "multi-consumer RTS V2 mode".
* - RING_F_MC_HTS_DEQ: If this flag is set, the default behavior when
* using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
* is "multi-consumer HTS mode".
@@ -149,6 +155,9 @@ int rte_ring_init(struct rte_ring *r, const char *name, unsigned int count,
* - RING_F_MP_RTS_ENQ: If this flag is set, the default behavior when
* using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
* is "multi-producer RTS mode".
+ * - RING_F_MP_RTS_V2_ENQ: If this flag is set, the default behavior when
+ * using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
+ * is "multi-producer RTS V2 mode".
* - RING_F_MP_HTS_ENQ: If this flag is set, the default behavior when
* using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
* is "multi-producer HTS mode".
@@ -161,6 +170,9 @@ int rte_ring_init(struct rte_ring *r, const char *name, unsigned int count,
* - RING_F_MC_RTS_DEQ: If this flag is set, the default behavior when
* using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
* is "multi-consumer RTS mode".
+ * - RING_F_MC_RTS_V2_DEQ: If this flag is set, the default behavior when
+ * using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
+ * is "multi-consumer RTS V2 mode".
* - RING_F_MC_HTS_DEQ: If this flag is set, the default behavior when
* using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
* is "multi-consumer HTS mode".
diff --git a/lib/ring/rte_ring_core.h b/lib/ring/rte_ring_core.h
index 6cd6ce9884..9e627d26c1 100644
--- a/lib/ring/rte_ring_core.h
+++ b/lib/ring/rte_ring_core.h
@@ -55,6 +55,7 @@ enum rte_ring_sync_type {
RTE_RING_SYNC_ST, /**< single thread only */
RTE_RING_SYNC_MT_RTS, /**< multi-thread relaxed tail sync */
RTE_RING_SYNC_MT_HTS, /**< multi-thread head/tail sync */
+ RTE_RING_SYNC_MT_RTS_V2, /**< multi-thread relaxed tail sync v2 */
};
/**
@@ -82,11 +83,16 @@ union __rte_ring_rts_poscnt {
} val;
};
+struct rte_ring_rts_cache {
+ volatile RTE_ATOMIC(uint32_t) num; /**< Number of objs. */
+};
+
struct rte_ring_rts_headtail {
volatile union __rte_ring_rts_poscnt tail;
enum rte_ring_sync_type sync_type; /**< sync type of prod/cons */
uint32_t htd_max; /**< max allowed distance between head/tail */
volatile union __rte_ring_rts_poscnt head;
+ struct rte_ring_rts_cache *rts_cache; /**< Cache of prod/cons */
};
union __rte_ring_hts_pos {
@@ -163,4 +169,7 @@ struct rte_ring {
#define RING_F_MP_HTS_ENQ 0x0020 /**< The default enqueue is "MP HTS". */
#define RING_F_MC_HTS_DEQ 0x0040 /**< The default dequeue is "MC HTS". */
+#define RING_F_MP_RTS_V2_ENQ 0x0080 /**< The default enqueue is "MP RTS V2". */
+#define RING_F_MC_RTS_V2_DEQ 0x0100 /**< The default dequeue is "MC RTS V2". */
+
#endif /* _RTE_RING_CORE_H_ */
diff --git a/lib/ring/rte_ring_elem.h b/lib/ring/rte_ring_elem.h
index b96bfc003f..1352709f94 100644
--- a/lib/ring/rte_ring_elem.h
+++ b/lib/ring/rte_ring_elem.h
@@ -71,6 +71,9 @@ ssize_t rte_ring_get_memsize_elem(unsigned int esize, unsigned int count);
* - RING_F_MP_RTS_ENQ: If this flag is set, the default behavior when
* using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
* is "multi-producer RTS mode".
+ * - RING_F_MP_RTS_V2_ENQ: If this flag is set, the default behavior when
+ * using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
+ * is "multi-producer RTS V2 mode".
* - RING_F_MP_HTS_ENQ: If this flag is set, the default behavior when
* using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
* is "multi-producer HTS mode".
@@ -83,6 +86,9 @@ ssize_t rte_ring_get_memsize_elem(unsigned int esize, unsigned int count);
* - RING_F_MC_RTS_DEQ: If this flag is set, the default behavior when
* using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
* is "multi-consumer RTS mode".
+ * - RING_F_MC_RTS_V2_DEQ: If this flag is set, the default behavior when
+ * using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
+ * is "multi-consumer RTS V2 mode".
* - RING_F_MC_HTS_DEQ: If this flag is set, the default behavior when
* using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
* is "multi-consumer HTS mode".
@@ -203,6 +209,9 @@ rte_ring_enqueue_bulk_elem(struct rte_ring *r, const void *obj_table,
case RTE_RING_SYNC_MT_HTS:
return rte_ring_mp_hts_enqueue_bulk_elem(r, obj_table, esize, n,
free_space);
+ case RTE_RING_SYNC_MT_RTS_V2:
+ return rte_ring_mp_rts_v2_enqueue_bulk_elem(r, obj_table, esize, n,
+ free_space);
}
/* valid ring should never reach this point */
@@ -385,6 +394,9 @@ rte_ring_dequeue_bulk_elem(struct rte_ring *r, void *obj_table,
case RTE_RING_SYNC_MT_HTS:
return rte_ring_mc_hts_dequeue_bulk_elem(r, obj_table, esize,
n, available);
+ case RTE_RING_SYNC_MT_RTS_V2:
+ return rte_ring_mc_rts_v2_dequeue_bulk_elem(r, obj_table, esize,
+ n, available);
}
/* valid ring should never reach this point */
@@ -571,6 +583,9 @@ rte_ring_enqueue_burst_elem(struct rte_ring *r, const void *obj_table,
case RTE_RING_SYNC_MT_HTS:
return rte_ring_mp_hts_enqueue_burst_elem(r, obj_table, esize,
n, free_space);
+ case RTE_RING_SYNC_MT_RTS_V2:
+ return rte_ring_mp_rts_v2_enqueue_burst_elem(r, obj_table, esize,
+ n, free_space);
}
/* valid ring should never reach this point */
@@ -681,6 +696,9 @@ rte_ring_dequeue_burst_elem(struct rte_ring *r, void *obj_table,
case RTE_RING_SYNC_MT_HTS:
return rte_ring_mc_hts_dequeue_burst_elem(r, obj_table, esize,
n, available);
+ case RTE_RING_SYNC_MT_RTS_V2:
+ return rte_ring_mc_rts_v2_dequeue_burst_elem(r, obj_table, esize,
+ n, available);
}
/* valid ring should never reach this point */
diff --git a/lib/ring/rte_ring_rts.h b/lib/ring/rte_ring_rts.h
index d7a3863c83..b47e400452 100644
--- a/lib/ring/rte_ring_rts.h
+++ b/lib/ring/rte_ring_rts.h
@@ -84,6 +84,33 @@ rte_ring_mp_rts_enqueue_bulk_elem(struct rte_ring *r, const void *obj_table,
RTE_RING_QUEUE_FIXED, free_space);
}
+/**
+ * Enqueue several objects on the RTS ring (multi-producers safe).
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of objects.
+ * @param esize
+ * The size of ring element, in bytes. It must be a multiple of 4.
+ * This must be the same value used while creating the ring. Otherwise
+ * the results are undefined.
+ * @param n
+ * The number of objects to add in the ring from the obj_table.
+ * @param free_space
+ * if non-NULL, returns the amount of space in the ring after the
+ * enqueue operation has finished.
+ * @return
+ * The number of objects enqueued, either 0 or n
+ */
+static __rte_always_inline unsigned int
+rte_ring_mp_rts_v2_enqueue_bulk_elem(struct rte_ring *r, const void *obj_table,
+ unsigned int esize, unsigned int n, unsigned int *free_space)
+{
+ return __rte_ring_do_rts_v2_enqueue_elem(r, obj_table, esize, n,
+ RTE_RING_QUEUE_FIXED, free_space);
+}
+
/**
* Dequeue several objects from an RTS ring (multi-consumers safe).
*
@@ -111,6 +138,33 @@ rte_ring_mc_rts_dequeue_bulk_elem(struct rte_ring *r, void *obj_table,
RTE_RING_QUEUE_FIXED, available);
}
+/**
+ * Dequeue several objects from an RTS ring (multi-consumers safe).
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of objects that will be filled.
+ * @param esize
+ * The size of ring element, in bytes. It must be a multiple of 4.
+ * This must be the same value used while creating the ring. Otherwise
+ * the results are undefined.
+ * @param n
+ * The number of objects to dequeue from the ring to the obj_table.
+ * @param available
+ * If non-NULL, returns the number of remaining ring entries after the
+ * dequeue has finished.
+ * @return
+ * The number of objects dequeued, either 0 or n
+ */
+static __rte_always_inline unsigned int
+rte_ring_mc_rts_v2_dequeue_bulk_elem(struct rte_ring *r, void *obj_table,
+ unsigned int esize, unsigned int n, unsigned int *available)
+{
+ return __rte_ring_do_rts_v2_dequeue_elem(r, obj_table, esize, n,
+ RTE_RING_QUEUE_FIXED, available);
+}
+
/**
* Enqueue several objects on the RTS ring (multi-producers safe).
*
@@ -138,6 +192,33 @@ rte_ring_mp_rts_enqueue_burst_elem(struct rte_ring *r, const void *obj_table,
RTE_RING_QUEUE_VARIABLE, free_space);
}
+/**
+ * Enqueue several objects on the RTS ring (multi-producers safe).
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of objects.
+ * @param esize
+ * The size of ring element, in bytes. It must be a multiple of 4.
+ * This must be the same value used while creating the ring. Otherwise
+ * the results are undefined.
+ * @param n
+ * The number of objects to add in the ring from the obj_table.
+ * @param free_space
+ * if non-NULL, returns the amount of space in the ring after the
+ * enqueue operation has finished.
+ * @return
+ * - n: Actual number of objects enqueued.
+ */
+static __rte_always_inline unsigned int
+rte_ring_mp_rts_v2_enqueue_burst_elem(struct rte_ring *r, const void *obj_table,
+ unsigned int esize, unsigned int n, unsigned int *free_space)
+{
+ return __rte_ring_do_rts_v2_enqueue_elem(r, obj_table, esize, n,
+ RTE_RING_QUEUE_VARIABLE, free_space);
+}
+
/**
* Dequeue several objects from an RTS ring (multi-consumers safe).
* When the requested objects are more than the available objects,
@@ -167,6 +248,35 @@ rte_ring_mc_rts_dequeue_burst_elem(struct rte_ring *r, void *obj_table,
RTE_RING_QUEUE_VARIABLE, available);
}
+/**
+ * Dequeue several objects from an RTS ring (multi-consumers safe).
+ * When the requested objects are more than the available objects,
+ * only dequeue the actual number of objects.
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of objects that will be filled.
+ * @param esize
+ * The size of ring element, in bytes. It must be a multiple of 4.
+ * This must be the same value used while creating the ring. Otherwise
+ * the results are undefined.
+ * @param n
+ * The number of objects to dequeue from the ring to the obj_table.
+ * @param available
+ * If non-NULL, returns the number of remaining ring entries after the
+ * dequeue has finished.
+ * @return
+ * - n: Actual number of objects dequeued, 0 if ring is empty
+ */
+static __rte_always_inline unsigned int
+rte_ring_mc_rts_v2_dequeue_burst_elem(struct rte_ring *r, void *obj_table,
+ unsigned int esize, unsigned int n, unsigned int *available)
+{
+ return __rte_ring_do_rts_v2_dequeue_elem(r, obj_table, esize, n,
+ RTE_RING_QUEUE_VARIABLE, available);
+}
+
/**
* Enqueue several objects on the RTS ring (multi-producers safe).
*
@@ -213,6 +323,52 @@ rte_ring_mc_rts_dequeue_bulk(struct rte_ring *r, void **obj_table,
sizeof(uintptr_t), n, available);
}
+/**
+ * Enqueue several objects on the RTS V2 ring (multi-producers safe).
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of void * pointers (objects).
+ * @param n
+ * The number of objects to add in the ring from the obj_table.
+ * @param free_space
+ * if non-NULL, returns the amount of space in the ring after the
+ * enqueue operation has finished.
+ * @return
+ * The number of objects enqueued, either 0 or n
+ */
+static __rte_always_inline unsigned int
+rte_ring_mp_rts_v2_enqueue_bulk(struct rte_ring *r, void * const *obj_table,
+ unsigned int n, unsigned int *free_space)
+{
+ return rte_ring_mp_rts_v2_enqueue_bulk_elem(r, obj_table,
+ sizeof(uintptr_t), n, free_space);
+}
+
+/**
+ * Dequeue several objects from an RTS V2 ring (multi-consumers safe).
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of void * pointers (objects) that will be filled.
+ * @param n
+ * The number of objects to dequeue from the ring to the obj_table.
+ * @param available
+ * If non-NULL, returns the number of remaining ring entries after the
+ * dequeue has finished.
+ * @return
+ * The number of objects dequeued, either 0 or n
+ */
+static __rte_always_inline unsigned int
+rte_ring_mc_rts_v2_dequeue_bulk(struct rte_ring *r, void **obj_table,
+ unsigned int n, unsigned int *available)
+{
+ return rte_ring_mc_rts_v2_dequeue_bulk_elem(r, obj_table,
+ sizeof(uintptr_t), n, available);
+}
+
/**
* Enqueue several objects on the RTS ring (multi-producers safe).
*
@@ -261,6 +417,54 @@ rte_ring_mc_rts_dequeue_burst(struct rte_ring *r, void **obj_table,
sizeof(uintptr_t), n, available);
}
+/**
+ * Enqueue several objects on the RTS V2 ring (multi-producers safe).
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of void * pointers (objects).
+ * @param n
+ * The number of objects to add in the ring from the obj_table.
+ * @param free_space
+ * if non-NULL, returns the amount of space in the ring after the
+ * enqueue operation has finished.
+ * @return
+ * - n: Actual number of objects enqueued.
+ */
+static __rte_always_inline unsigned int
+rte_ring_mp_rts_v2_enqueue_burst(struct rte_ring *r, void * const *obj_table,
+ unsigned int n, unsigned int *free_space)
+{
+ return rte_ring_mp_rts_v2_enqueue_burst_elem(r, obj_table,
+ sizeof(uintptr_t), n, free_space);
+}
+
+/**
+ * Dequeue several objects from an RTS V2 ring (multi-consumers safe).
+ * When the requested objects are more than the available objects,
+ * only dequeue the actual number of objects.
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of void * pointers (objects) that will be filled.
+ * @param n
+ * The number of objects to dequeue from the ring to the obj_table.
+ * @param available
+ * If non-NULL, returns the number of remaining ring entries after the
+ * dequeue has finished.
+ * @return
+ * - n: Actual number of objects dequeued, 0 if ring is empty
+ */
+static __rte_always_inline unsigned int
+rte_ring_mc_rts_v2_dequeue_burst(struct rte_ring *r, void **obj_table,
+ unsigned int n, unsigned int *available)
+{
+ return rte_ring_mc_rts_v2_dequeue_burst_elem(r, obj_table,
+ sizeof(uintptr_t), n, available);
+}
+
/**
* Return producer max Head-Tail-Distance (HTD).
*
@@ -273,7 +477,8 @@ rte_ring_mc_rts_dequeue_burst(struct rte_ring *r, void **obj_table,
static inline uint32_t
rte_ring_get_prod_htd_max(const struct rte_ring *r)
{
- if (r->prod.sync_type == RTE_RING_SYNC_MT_RTS)
+ if ((r->prod.sync_type == RTE_RING_SYNC_MT_RTS) ||
+ (r->prod.sync_type == RTE_RING_SYNC_MT_RTS_V2))
return r->rts_prod.htd_max;
return UINT32_MAX;
}
@@ -292,7 +497,8 @@ rte_ring_get_prod_htd_max(const struct rte_ring *r)
static inline int
rte_ring_set_prod_htd_max(struct rte_ring *r, uint32_t v)
{
- if (r->prod.sync_type != RTE_RING_SYNC_MT_RTS)
+ if ((r->prod.sync_type != RTE_RING_SYNC_MT_RTS) &&
+ (r->prod.sync_type != RTE_RING_SYNC_MT_RTS_V2))
return -ENOTSUP;
r->rts_prod.htd_max = v;
@@ -311,7 +517,8 @@ rte_ring_set_prod_htd_max(struct rte_ring *r, uint32_t v)
static inline uint32_t
rte_ring_get_cons_htd_max(const struct rte_ring *r)
{
- if (r->cons.sync_type == RTE_RING_SYNC_MT_RTS)
+ if ((r->cons.sync_type == RTE_RING_SYNC_MT_RTS) ||
+ (r->cons.sync_type == RTE_RING_SYNC_MT_RTS_V2))
return r->rts_cons.htd_max;
return UINT32_MAX;
}
@@ -330,7 +537,8 @@ rte_ring_get_cons_htd_max(const struct rte_ring *r)
static inline int
rte_ring_set_cons_htd_max(struct rte_ring *r, uint32_t v)
{
- if (r->cons.sync_type != RTE_RING_SYNC_MT_RTS)
+ if ((r->cons.sync_type != RTE_RING_SYNC_MT_RTS) &&
+ (r->cons.sync_type != RTE_RING_SYNC_MT_RTS_V2))
return -ENOTSUP;
r->rts_cons.htd_max = v;
diff --git a/lib/ring/rte_ring_rts_elem_pvt.h b/lib/ring/rte_ring_rts_elem_pvt.h
index 122650346b..4ce22a93ed 100644
--- a/lib/ring/rte_ring_rts_elem_pvt.h
+++ b/lib/ring/rte_ring_rts_elem_pvt.h
@@ -46,6 +46,92 @@ __rte_ring_rts_update_tail(struct rte_ring_rts_headtail *ht)
rte_memory_order_release, rte_memory_order_acquire) == 0);
}
+/**
+ * @file rte_ring_rts_elem_pvt.h
+ * It is not recommended to include this file directly,
+ * include <rte_ring.h> instead.
+ * Contains internal helper functions for Relaxed Tail Sync (RTS) ring mode.
+ * For more information please refer to <rte_ring_rts.h>.
+ */
+
+/**
+ * @internal This function updates tail values.
+ */
+static __rte_always_inline void
+__rte_ring_rts_v2_update_tail(struct rte_ring_rts_headtail *ht,
+ uint32_t old_tail, uint32_t num, uint32_t mask)
+{
+ union __rte_ring_rts_poscnt ot, nt;
+
+ ot.val.cnt = nt.val.cnt = 0;
+ ot.val.pos = old_tail;
+ nt.val.pos = old_tail + num;
+
+ /*
+ * If the tail is equal to the current enqueues/dequeues, update
+ * the tail with new value and then continue to try to update the
+ * tail until the num of the cache is 0, otherwise write the num of
+ * the current enqueues/dequeues to the cache.
+ */
+
+ if (rte_atomic_compare_exchange_strong_explicit(&ht->tail.raw,
+ (uint64_t *)(uintptr_t)&ot.raw, nt.raw,
+ rte_memory_order_release, rte_memory_order_acquire) == 0) {
+ ot.val.pos = old_tail;
+
+ /*
+ * Write the num of the current enqueues/dequeues to the
+ * corresponding cache.
+ */
+ rte_atomic_store_explicit(&ht->rts_cache[ot.val.pos & mask].num,
+ num, rte_memory_order_release);
+
+ /*
+ * There may be competition with another enqueues/dequeues
+ * for the update tail. The winner continues to try to update
+ * the tail, and the loser exits.
+ */
+ if (rte_atomic_compare_exchange_strong_explicit(&ht->tail.raw,
+ (uint64_t *)(uintptr_t)&ot.raw, nt.raw,
+ rte_memory_order_release, rte_memory_order_acquire) == 0)
+ return;
+
+ /*
+ * Set the corresponding cache to 0 for next use.
+ */
+ rte_atomic_store_explicit(&ht->rts_cache[ot.val.pos & mask].num,
+ 0, rte_memory_order_release);
+ }
+
+ /*
+ * Try to update the tail until the num of the corresponding cache is 0.
+ * Getting here means that the current enqueues/dequeues is trying to update
+ * the tail of another enqueues/dequeues.
+ */
+ while (1) {
+ num = rte_atomic_load_explicit(&ht->rts_cache[nt.val.pos & mask].num,
+ rte_memory_order_acquire);
+ if (num == 0)
+ break;
+
+ ot.val.pos = nt.val.pos;
+ nt.val.pos += num;
+
+ /*
+ * There may be competition with another enqueues/dequeues
+ * for the update tail. The winner continues to try to update
+ * the tail, and the loser exits.
+ */
+ if (rte_atomic_compare_exchange_strong_explicit(&ht->tail.raw,
+ (uint64_t *)(uintptr_t)&ot.raw, nt.raw,
+ rte_memory_order_release, rte_memory_order_acquire) == 0)
+ return;
+
+ rte_atomic_store_explicit(&ht->rts_cache[ot.val.pos & mask].num,
+ 0, rte_memory_order_release);
+ };
+}
+
/**
* @internal This function waits till head/tail distance wouldn't
* exceed pre-defined max value.
@@ -218,6 +304,47 @@ __rte_ring_do_rts_enqueue_elem(struct rte_ring *r, const void *obj_table,
return n;
}
+/**
+ * @internal Enqueue several objects on the RTS ring.
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of objects.
+ * @param esize
+ * The size of ring element, in bytes. It must be a multiple of 4.
+ * This must be the same value used while creating the ring. Otherwise
+ * the results are undefined.
+ * @param n
+ * The number of objects to add in the ring from the obj_table.
+ * @param behavior
+ * RTE_RING_QUEUE_FIXED: Enqueue a fixed number of items from a ring
+ * RTE_RING_QUEUE_VARIABLE: Enqueue as many items as possible from ring
+ * @param free_space
+ * returns the amount of space after the enqueue operation has finished
+ * @return
+ * Actual number of objects enqueued.
+ * If behavior == RTE_RING_QUEUE_FIXED, this will be 0 or n only.
+ */
+static __rte_always_inline unsigned int
+__rte_ring_do_rts_v2_enqueue_elem(struct rte_ring *r, const void *obj_table,
+ uint32_t esize, uint32_t n, enum rte_ring_queue_behavior behavior,
+ uint32_t *free_space)
+{
+ uint32_t free, head;
+
+ n = __rte_ring_rts_move_prod_head(r, n, behavior, &head, &free);
+
+ if (n != 0) {
+ __rte_ring_enqueue_elems(r, head, obj_table, esize, n);
+ __rte_ring_rts_v2_update_tail(&r->rts_prod, head, n, r->mask);
+ }
+
+ if (free_space != NULL)
+ *free_space = free - n;
+ return n;
+}
+
/**
* @internal Dequeue several objects from the RTS ring.
*
@@ -259,4 +386,45 @@ __rte_ring_do_rts_dequeue_elem(struct rte_ring *r, void *obj_table,
return n;
}
+/**
+ * @internal Dequeue several objects from the RTS ring.
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of objects.
+ * @param esize
+ * The size of ring element, in bytes. It must be a multiple of 4.
+ * This must be the same value used while creating the ring. Otherwise
+ * the results are undefined.
+ * @param n
+ * The number of objects to pull from the ring.
+ * @param behavior
+ * RTE_RING_QUEUE_FIXED: Dequeue a fixed number of items from a ring
+ * RTE_RING_QUEUE_VARIABLE: Dequeue as many items as possible from ring
+ * @param available
+ * returns the number of remaining ring entries after the dequeue has finished
+ * @return
+ * - Actual number of objects dequeued.
+ * If behavior == RTE_RING_QUEUE_FIXED, this will be 0 or n only.
+ */
+static __rte_always_inline unsigned int
+__rte_ring_do_rts_v2_dequeue_elem(struct rte_ring *r, void *obj_table,
+ uint32_t esize, uint32_t n, enum rte_ring_queue_behavior behavior,
+ uint32_t *available)
+{
+ uint32_t entries, head;
+
+ n = __rte_ring_rts_move_cons_head(r, n, behavior, &head, &entries);
+
+ if (n != 0) {
+ __rte_ring_dequeue_elems(r, head, obj_table, esize, n);
+ __rte_ring_rts_v2_update_tail(&r->rts_cons, head, n, r->mask);
+ }
+
+ if (available != NULL)
+ *available = entries - n;
+ return n;
+}
+
#endif /* _RTE_RING_RTS_ELEM_PVT_H_ */
--
2.27.0
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH v2] ring: add the second version of the RTS interface
2025-01-05 9:57 [PATCH] " Huichao Cai
@ 2025-01-05 15:13 ` Huichao Cai
2025-01-08 1:41 ` Huichao Cai
2025-01-08 16:49 ` Konstantin Ananyev
0 siblings, 2 replies; 4+ messages in thread
From: Huichao Cai @ 2025-01-05 15:13 UTC (permalink / raw)
To: honnappa.nagarahalli, konstantin.v.ananyev, thomas; +Cc: dev
The timing of the update of the RTS enqueues/dequeues tail is
limited to the last enqueues/dequeues, which reduces concurrency,
so the RTS interface of the V2 version is added, which makes the tail
of the enqueues/dequeues not limited to the last enqueues/dequeues
and thus enables timely updates to increase concurrency.
Add some corresponding test cases.
Signed-off-by: Huichao Cai <chcchc88@163.com>
---
app/test/meson.build | 1 +
app/test/test_ring.c | 26 +++
app/test/test_ring_rts_v2_stress.c | 32 ++++
app/test/test_ring_stress.c | 3 +
app/test/test_ring_stress.h | 1 +
devtools/libabigail.abignore | 6 +
doc/guides/rel_notes/release_25_03.rst | 2 +
lib/ring/rte_ring.c | 54 ++++++-
lib/ring/rte_ring.h | 12 ++
lib/ring/rte_ring_core.h | 9 ++
lib/ring/rte_ring_elem.h | 18 +++
lib/ring/rte_ring_rts.h | 216 ++++++++++++++++++++++++-
lib/ring/rte_ring_rts_elem_pvt.h | 168 +++++++++++++++++++
13 files changed, 538 insertions(+), 10 deletions(-)
create mode 100644 app/test/test_ring_rts_v2_stress.c
diff --git a/app/test/meson.build b/app/test/meson.build
index d5cb6a7f7a..e3d8cef3fa 100644
--- a/app/test/meson.build
+++ b/app/test/meson.build
@@ -166,6 +166,7 @@ source_file_deps = {
'test_ring_mt_peek_stress_zc.c': ['ptr_compress'],
'test_ring_perf.c': ['ptr_compress'],
'test_ring_rts_stress.c': ['ptr_compress'],
+ 'test_ring_rts_v2_stress.c': ['ptr_compress'],
'test_ring_st_peek_stress.c': ['ptr_compress'],
'test_ring_st_peek_stress_zc.c': ['ptr_compress'],
'test_ring_stress.c': ['ptr_compress'],
diff --git a/app/test/test_ring.c b/app/test/test_ring.c
index ba1fec1de3..094f14b859 100644
--- a/app/test/test_ring.c
+++ b/app/test/test_ring.c
@@ -284,6 +284,19 @@ static const struct {
.felem = rte_ring_dequeue_bulk_elem,
},
},
+ {
+ .desc = "MP_RTS/MC_RTS V2 sync mode",
+ .api_type = TEST_RING_ELEM_BULK | TEST_RING_THREAD_DEF,
+ .create_flags = RING_F_MP_RTS_V2_ENQ | RING_F_MC_RTS_V2_DEQ,
+ .enq = {
+ .flegacy = rte_ring_enqueue_bulk,
+ .felem = rte_ring_enqueue_bulk_elem,
+ },
+ .deq = {
+ .flegacy = rte_ring_dequeue_bulk,
+ .felem = rte_ring_dequeue_bulk_elem,
+ },
+ },
{
.desc = "MP_HTS/MC_HTS sync mode",
.api_type = TEST_RING_ELEM_BULK | TEST_RING_THREAD_DEF,
@@ -349,6 +362,19 @@ static const struct {
.felem = rte_ring_dequeue_burst_elem,
},
},
+ {
+ .desc = "MP_RTS/MC_RTS V2 sync mode",
+ .api_type = TEST_RING_ELEM_BURST | TEST_RING_THREAD_DEF,
+ .create_flags = RING_F_MP_RTS_V2_ENQ | RING_F_MC_RTS_V2_DEQ,
+ .enq = {
+ .flegacy = rte_ring_enqueue_burst,
+ .felem = rte_ring_enqueue_burst_elem,
+ },
+ .deq = {
+ .flegacy = rte_ring_dequeue_burst,
+ .felem = rte_ring_dequeue_burst_elem,
+ },
+ },
{
.desc = "MP_HTS/MC_HTS sync mode",
.api_type = TEST_RING_ELEM_BURST | TEST_RING_THREAD_DEF,
diff --git a/app/test/test_ring_rts_v2_stress.c b/app/test/test_ring_rts_v2_stress.c
new file mode 100644
index 0000000000..6079366a7d
--- /dev/null
+++ b/app/test/test_ring_rts_v2_stress.c
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2020 Intel Corporation
+ */
+
+#include "test_ring_stress_impl.h"
+
+static inline uint32_t
+_st_ring_dequeue_bulk(struct rte_ring *r, void **obj, uint32_t n,
+ uint32_t *avail)
+{
+ return rte_ring_mc_rts_v2_dequeue_bulk(r, obj, n, avail);
+}
+
+static inline uint32_t
+_st_ring_enqueue_bulk(struct rte_ring *r, void * const *obj, uint32_t n,
+ uint32_t *free)
+{
+ return rte_ring_mp_rts_v2_enqueue_bulk(r, obj, n, free);
+}
+
+static int
+_st_ring_init(struct rte_ring *r, const char *name, uint32_t num)
+{
+ return rte_ring_init(r, name, num,
+ RING_F_MP_RTS_V2_ENQ | RING_F_MC_RTS_V2_DEQ);
+}
+
+const struct test test_ring_rts_v2_stress = {
+ .name = "MT_RTS_V2",
+ .nb_case = RTE_DIM(tests),
+ .cases = tests,
+};
diff --git a/app/test/test_ring_stress.c b/app/test/test_ring_stress.c
index 1af45e0fc8..94085acd5e 100644
--- a/app/test/test_ring_stress.c
+++ b/app/test/test_ring_stress.c
@@ -43,6 +43,9 @@ test_ring_stress(void)
n += test_ring_rts_stress.nb_case;
k += run_test(&test_ring_rts_stress);
+ n += test_ring_rts_v2_stress.nb_case;
+ k += run_test(&test_ring_rts_v2_stress);
+
n += test_ring_hts_stress.nb_case;
k += run_test(&test_ring_hts_stress);
diff --git a/app/test/test_ring_stress.h b/app/test/test_ring_stress.h
index 416d68c9a0..505957f6fb 100644
--- a/app/test/test_ring_stress.h
+++ b/app/test/test_ring_stress.h
@@ -34,6 +34,7 @@ struct test {
extern const struct test test_ring_mpmc_stress;
extern const struct test test_ring_rts_stress;
+extern const struct test test_ring_rts_v2_stress;
extern const struct test test_ring_hts_stress;
extern const struct test test_ring_mt_peek_stress;
extern const struct test test_ring_mt_peek_stress_zc;
diff --git a/devtools/libabigail.abignore b/devtools/libabigail.abignore
index 21b8cd6113..d4dd99a99e 100644
--- a/devtools/libabigail.abignore
+++ b/devtools/libabigail.abignore
@@ -33,3 +33,9 @@
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; Temporary exceptions till next major ABI version ;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+[suppress_type]
+ type_kind = struct
+ name = rte_ring_rts_cache
+[suppress_type]
+ name = rte_ring_rts_headtail
+ has_data_member_inserted_between = {offset_of(head), end}
diff --git a/doc/guides/rel_notes/release_25_03.rst b/doc/guides/rel_notes/release_25_03.rst
index 426dfcd982..f73bc9e397 100644
--- a/doc/guides/rel_notes/release_25_03.rst
+++ b/doc/guides/rel_notes/release_25_03.rst
@@ -102,6 +102,8 @@ ABI Changes
* No ABI change that would break compatibility with 24.11.
+* ring: Added ``rte_ring_rts_cache`` structure and ``rts_cache`` field to the
+ ``rte_ring_rts_headtail`` structure.
Known Issues
------------
diff --git a/lib/ring/rte_ring.c b/lib/ring/rte_ring.c
index aebb6d6728..ada1ae88fa 100644
--- a/lib/ring/rte_ring.c
+++ b/lib/ring/rte_ring.c
@@ -43,7 +43,8 @@ EAL_REGISTER_TAILQ(rte_ring_tailq)
/* mask of all valid flag values to ring_create() */
#define RING_F_MASK (RING_F_SP_ENQ | RING_F_SC_DEQ | RING_F_EXACT_SZ | \
RING_F_MP_RTS_ENQ | RING_F_MC_RTS_DEQ | \
- RING_F_MP_HTS_ENQ | RING_F_MC_HTS_DEQ)
+ RING_F_MP_HTS_ENQ | RING_F_MC_HTS_DEQ | \
+ RING_F_MP_RTS_V2_ENQ | RING_F_MC_RTS_V2_DEQ)
/* true if x is a power of 2 */
#define POWEROF2(x) ((((x)-1) & (x)) == 0)
@@ -106,6 +107,7 @@ reset_headtail(void *p)
ht->tail = 0;
break;
case RTE_RING_SYNC_MT_RTS:
+ case RTE_RING_SYNC_MT_RTS_V2:
ht_rts->head.raw = 0;
ht_rts->tail.raw = 0;
break;
@@ -135,9 +137,11 @@ get_sync_type(uint32_t flags, enum rte_ring_sync_type *prod_st,
enum rte_ring_sync_type *cons_st)
{
static const uint32_t prod_st_flags =
- (RING_F_SP_ENQ | RING_F_MP_RTS_ENQ | RING_F_MP_HTS_ENQ);
+ (RING_F_SP_ENQ | RING_F_MP_RTS_ENQ | RING_F_MP_HTS_ENQ |
+ RING_F_MP_RTS_V2_ENQ);
static const uint32_t cons_st_flags =
- (RING_F_SC_DEQ | RING_F_MC_RTS_DEQ | RING_F_MC_HTS_DEQ);
+ (RING_F_SC_DEQ | RING_F_MC_RTS_DEQ | RING_F_MC_HTS_DEQ |
+ RING_F_MC_RTS_V2_DEQ);
switch (flags & prod_st_flags) {
case 0:
@@ -152,6 +156,9 @@ get_sync_type(uint32_t flags, enum rte_ring_sync_type *prod_st,
case RING_F_MP_HTS_ENQ:
*prod_st = RTE_RING_SYNC_MT_HTS;
break;
+ case RING_F_MP_RTS_V2_ENQ:
+ *prod_st = RTE_RING_SYNC_MT_RTS_V2;
+ break;
default:
return -EINVAL;
}
@@ -169,6 +176,9 @@ get_sync_type(uint32_t flags, enum rte_ring_sync_type *prod_st,
case RING_F_MC_HTS_DEQ:
*cons_st = RTE_RING_SYNC_MT_HTS;
break;
+ case RING_F_MC_RTS_V2_DEQ:
+ *cons_st = RTE_RING_SYNC_MT_RTS_V2;
+ break;
default:
return -EINVAL;
}
@@ -239,6 +249,28 @@ rte_ring_init(struct rte_ring *r, const char *name, unsigned int count,
if (flags & RING_F_MC_RTS_DEQ)
rte_ring_set_cons_htd_max(r, r->capacity / HTD_MAX_DEF);
+ /* set default values for head-tail distance and allocate memory to cache */
+ if (flags & RING_F_MP_RTS_V2_ENQ) {
+ rte_ring_set_prod_htd_max(r, r->capacity / HTD_MAX_DEF);
+ r->rts_prod.rts_cache = (struct rte_ring_rts_cache *)rte_zmalloc(
+ "RTS_PROD_CACHE", sizeof(struct rte_ring_rts_cache) * r->size, 0);
+ if (r->rts_prod.rts_cache == NULL) {
+ RING_LOG(ERR, "Cannot reserve memory for rts prod cache");
+ return -ENOMEM;
+ }
+ }
+ if (flags & RING_F_MC_RTS_V2_DEQ) {
+ rte_ring_set_cons_htd_max(r, r->capacity / HTD_MAX_DEF);
+ r->rts_cons.rts_cache = (struct rte_ring_rts_cache *)rte_zmalloc(
+ "RTS_CONS_CACHE", sizeof(struct rte_ring_rts_cache) * r->size, 0);
+ if (r->rts_cons.rts_cache == NULL) {
+ if (flags & RING_F_MP_RTS_V2_ENQ)
+ rte_free(r->rts_prod.rts_cache);
+ RING_LOG(ERR, "Cannot reserve memory for rts cons cache");
+ return -ENOMEM;
+ }
+ }
+
return 0;
}
@@ -293,9 +325,14 @@ rte_ring_create_elem(const char *name, unsigned int esize, unsigned int count,
mz_flags, alignof(typeof(*r)));
if (mz != NULL) {
r = mz->addr;
- /* no need to check return value here, we already checked the
- * arguments above */
- rte_ring_init(r, name, requested_count, flags);
+
+ if (rte_ring_init(r, name, requested_count, flags)) {
+ rte_free(te);
+ if (rte_memzone_free(mz) != 0)
+ RING_LOG(ERR, "Cannot free memory for ring");
+ rte_mcfg_tailq_write_unlock();
+ return NULL;
+ }
te->data = (void *) r;
r->memzone = mz;
@@ -358,6 +395,11 @@ rte_ring_free(struct rte_ring *r)
rte_mcfg_tailq_write_unlock();
+ if (r->flags & RING_F_MP_RTS_V2_ENQ)
+ rte_free(r->rts_prod.rts_cache);
+ if (r->flags & RING_F_MC_RTS_V2_DEQ)
+ rte_free(r->rts_cons.rts_cache);
+
if (rte_memzone_free(r->memzone) != 0)
RING_LOG(ERR, "Cannot free memory");
diff --git a/lib/ring/rte_ring.h b/lib/ring/rte_ring.h
index 11ca69c73d..2b35ce038e 100644
--- a/lib/ring/rte_ring.h
+++ b/lib/ring/rte_ring.h
@@ -89,6 +89,9 @@ ssize_t rte_ring_get_memsize(unsigned int count);
* - RING_F_MP_RTS_ENQ: If this flag is set, the default behavior when
* using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
* is "multi-producer RTS mode".
+ * - RING_F_MP_RTS_V2_ENQ: If this flag is set, the default behavior when
+ * using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
+ * is "multi-producer RTS V2 mode".
* - RING_F_MP_HTS_ENQ: If this flag is set, the default behavior when
* using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
* is "multi-producer HTS mode".
@@ -101,6 +104,9 @@ ssize_t rte_ring_get_memsize(unsigned int count);
* - RING_F_MC_RTS_DEQ: If this flag is set, the default behavior when
* using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
* is "multi-consumer RTS mode".
+ * - RING_F_MC_RTS_V2_DEQ: If this flag is set, the default behavior when
+ * using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
+ * is "multi-consumer RTS V2 mode".
* - RING_F_MC_HTS_DEQ: If this flag is set, the default behavior when
* using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
* is "multi-consumer HTS mode".
@@ -149,6 +155,9 @@ int rte_ring_init(struct rte_ring *r, const char *name, unsigned int count,
* - RING_F_MP_RTS_ENQ: If this flag is set, the default behavior when
* using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
* is "multi-producer RTS mode".
+ * - RING_F_MP_RTS_V2_ENQ: If this flag is set, the default behavior when
+ * using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
+ * is "multi-producer RTS V2 mode".
* - RING_F_MP_HTS_ENQ: If this flag is set, the default behavior when
* using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
* is "multi-producer HTS mode".
@@ -161,6 +170,9 @@ int rte_ring_init(struct rte_ring *r, const char *name, unsigned int count,
* - RING_F_MC_RTS_DEQ: If this flag is set, the default behavior when
* using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
* is "multi-consumer RTS mode".
+ * - RING_F_MC_RTS_V2_DEQ: If this flag is set, the default behavior when
+ * using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
+ * is "multi-consumer RTS V2 mode".
* - RING_F_MC_HTS_DEQ: If this flag is set, the default behavior when
* using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
* is "multi-consumer HTS mode".
diff --git a/lib/ring/rte_ring_core.h b/lib/ring/rte_ring_core.h
index 6cd6ce9884..9e627d26c1 100644
--- a/lib/ring/rte_ring_core.h
+++ b/lib/ring/rte_ring_core.h
@@ -55,6 +55,7 @@ enum rte_ring_sync_type {
RTE_RING_SYNC_ST, /**< single thread only */
RTE_RING_SYNC_MT_RTS, /**< multi-thread relaxed tail sync */
RTE_RING_SYNC_MT_HTS, /**< multi-thread head/tail sync */
+ RTE_RING_SYNC_MT_RTS_V2, /**< multi-thread relaxed tail sync v2 */
};
/**
@@ -82,11 +83,16 @@ union __rte_ring_rts_poscnt {
} val;
};
+struct rte_ring_rts_cache {
+ volatile RTE_ATOMIC(uint32_t) num; /**< Number of objs. */
+};
+
struct rte_ring_rts_headtail {
volatile union __rte_ring_rts_poscnt tail;
enum rte_ring_sync_type sync_type; /**< sync type of prod/cons */
uint32_t htd_max; /**< max allowed distance between head/tail */
volatile union __rte_ring_rts_poscnt head;
+ struct rte_ring_rts_cache *rts_cache; /**< Cache of prod/cons */
};
union __rte_ring_hts_pos {
@@ -163,4 +169,7 @@ struct rte_ring {
#define RING_F_MP_HTS_ENQ 0x0020 /**< The default enqueue is "MP HTS". */
#define RING_F_MC_HTS_DEQ 0x0040 /**< The default dequeue is "MC HTS". */
+#define RING_F_MP_RTS_V2_ENQ 0x0080 /**< The default enqueue is "MP RTS V2". */
+#define RING_F_MC_RTS_V2_DEQ 0x0100 /**< The default dequeue is "MC RTS V2". */
+
#endif /* _RTE_RING_CORE_H_ */
diff --git a/lib/ring/rte_ring_elem.h b/lib/ring/rte_ring_elem.h
index b96bfc003f..1352709f94 100644
--- a/lib/ring/rte_ring_elem.h
+++ b/lib/ring/rte_ring_elem.h
@@ -71,6 +71,9 @@ ssize_t rte_ring_get_memsize_elem(unsigned int esize, unsigned int count);
* - RING_F_MP_RTS_ENQ: If this flag is set, the default behavior when
* using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
* is "multi-producer RTS mode".
+ * - RING_F_MP_RTS_V2_ENQ: If this flag is set, the default behavior when
+ * using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
+ * is "multi-producer RTS V2 mode".
* - RING_F_MP_HTS_ENQ: If this flag is set, the default behavior when
* using ``rte_ring_enqueue()`` or ``rte_ring_enqueue_bulk()``
* is "multi-producer HTS mode".
@@ -83,6 +86,9 @@ ssize_t rte_ring_get_memsize_elem(unsigned int esize, unsigned int count);
* - RING_F_MC_RTS_DEQ: If this flag is set, the default behavior when
* using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
* is "multi-consumer RTS mode".
+ * - RING_F_MC_RTS_V2_DEQ: If this flag is set, the default behavior when
+ * using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
+ * is "multi-consumer RTS V2 mode".
* - RING_F_MC_HTS_DEQ: If this flag is set, the default behavior when
* using ``rte_ring_dequeue()`` or ``rte_ring_dequeue_bulk()``
* is "multi-consumer HTS mode".
@@ -203,6 +209,9 @@ rte_ring_enqueue_bulk_elem(struct rte_ring *r, const void *obj_table,
case RTE_RING_SYNC_MT_HTS:
return rte_ring_mp_hts_enqueue_bulk_elem(r, obj_table, esize, n,
free_space);
+ case RTE_RING_SYNC_MT_RTS_V2:
+ return rte_ring_mp_rts_v2_enqueue_bulk_elem(r, obj_table, esize, n,
+ free_space);
}
/* valid ring should never reach this point */
@@ -385,6 +394,9 @@ rte_ring_dequeue_bulk_elem(struct rte_ring *r, void *obj_table,
case RTE_RING_SYNC_MT_HTS:
return rte_ring_mc_hts_dequeue_bulk_elem(r, obj_table, esize,
n, available);
+ case RTE_RING_SYNC_MT_RTS_V2:
+ return rte_ring_mc_rts_v2_dequeue_bulk_elem(r, obj_table, esize,
+ n, available);
}
/* valid ring should never reach this point */
@@ -571,6 +583,9 @@ rte_ring_enqueue_burst_elem(struct rte_ring *r, const void *obj_table,
case RTE_RING_SYNC_MT_HTS:
return rte_ring_mp_hts_enqueue_burst_elem(r, obj_table, esize,
n, free_space);
+ case RTE_RING_SYNC_MT_RTS_V2:
+ return rte_ring_mp_rts_v2_enqueue_burst_elem(r, obj_table, esize,
+ n, free_space);
}
/* valid ring should never reach this point */
@@ -681,6 +696,9 @@ rte_ring_dequeue_burst_elem(struct rte_ring *r, void *obj_table,
case RTE_RING_SYNC_MT_HTS:
return rte_ring_mc_hts_dequeue_burst_elem(r, obj_table, esize,
n, available);
+ case RTE_RING_SYNC_MT_RTS_V2:
+ return rte_ring_mc_rts_v2_dequeue_burst_elem(r, obj_table, esize,
+ n, available);
}
/* valid ring should never reach this point */
diff --git a/lib/ring/rte_ring_rts.h b/lib/ring/rte_ring_rts.h
index d7a3863c83..b47e400452 100644
--- a/lib/ring/rte_ring_rts.h
+++ b/lib/ring/rte_ring_rts.h
@@ -84,6 +84,33 @@ rte_ring_mp_rts_enqueue_bulk_elem(struct rte_ring *r, const void *obj_table,
RTE_RING_QUEUE_FIXED, free_space);
}
+/**
+ * Enqueue several objects on the RTS ring (multi-producers safe).
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of objects.
+ * @param esize
+ * The size of ring element, in bytes. It must be a multiple of 4.
+ * This must be the same value used while creating the ring. Otherwise
+ * the results are undefined.
+ * @param n
+ * The number of objects to add in the ring from the obj_table.
+ * @param free_space
+ * if non-NULL, returns the amount of space in the ring after the
+ * enqueue operation has finished.
+ * @return
+ * The number of objects enqueued, either 0 or n
+ */
+static __rte_always_inline unsigned int
+rte_ring_mp_rts_v2_enqueue_bulk_elem(struct rte_ring *r, const void *obj_table,
+ unsigned int esize, unsigned int n, unsigned int *free_space)
+{
+ return __rte_ring_do_rts_v2_enqueue_elem(r, obj_table, esize, n,
+ RTE_RING_QUEUE_FIXED, free_space);
+}
+
/**
* Dequeue several objects from an RTS ring (multi-consumers safe).
*
@@ -111,6 +138,33 @@ rte_ring_mc_rts_dequeue_bulk_elem(struct rte_ring *r, void *obj_table,
RTE_RING_QUEUE_FIXED, available);
}
+/**
+ * Dequeue several objects from an RTS ring (multi-consumers safe).
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of objects that will be filled.
+ * @param esize
+ * The size of ring element, in bytes. It must be a multiple of 4.
+ * This must be the same value used while creating the ring. Otherwise
+ * the results are undefined.
+ * @param n
+ * The number of objects to dequeue from the ring to the obj_table.
+ * @param available
+ * If non-NULL, returns the number of remaining ring entries after the
+ * dequeue has finished.
+ * @return
+ * The number of objects dequeued, either 0 or n
+ */
+static __rte_always_inline unsigned int
+rte_ring_mc_rts_v2_dequeue_bulk_elem(struct rte_ring *r, void *obj_table,
+ unsigned int esize, unsigned int n, unsigned int *available)
+{
+ return __rte_ring_do_rts_v2_dequeue_elem(r, obj_table, esize, n,
+ RTE_RING_QUEUE_FIXED, available);
+}
+
/**
* Enqueue several objects on the RTS ring (multi-producers safe).
*
@@ -138,6 +192,33 @@ rte_ring_mp_rts_enqueue_burst_elem(struct rte_ring *r, const void *obj_table,
RTE_RING_QUEUE_VARIABLE, free_space);
}
+/**
+ * Enqueue several objects on the RTS ring (multi-producers safe).
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of objects.
+ * @param esize
+ * The size of ring element, in bytes. It must be a multiple of 4.
+ * This must be the same value used while creating the ring. Otherwise
+ * the results are undefined.
+ * @param n
+ * The number of objects to add in the ring from the obj_table.
+ * @param free_space
+ * if non-NULL, returns the amount of space in the ring after the
+ * enqueue operation has finished.
+ * @return
+ * - n: Actual number of objects enqueued.
+ */
+static __rte_always_inline unsigned int
+rte_ring_mp_rts_v2_enqueue_burst_elem(struct rte_ring *r, const void *obj_table,
+ unsigned int esize, unsigned int n, unsigned int *free_space)
+{
+ return __rte_ring_do_rts_v2_enqueue_elem(r, obj_table, esize, n,
+ RTE_RING_QUEUE_VARIABLE, free_space);
+}
+
/**
* Dequeue several objects from an RTS ring (multi-consumers safe).
* When the requested objects are more than the available objects,
@@ -167,6 +248,35 @@ rte_ring_mc_rts_dequeue_burst_elem(struct rte_ring *r, void *obj_table,
RTE_RING_QUEUE_VARIABLE, available);
}
+/**
+ * Dequeue several objects from an RTS ring (multi-consumers safe).
+ * When the requested objects are more than the available objects,
+ * only dequeue the actual number of objects.
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of objects that will be filled.
+ * @param esize
+ * The size of ring element, in bytes. It must be a multiple of 4.
+ * This must be the same value used while creating the ring. Otherwise
+ * the results are undefined.
+ * @param n
+ * The number of objects to dequeue from the ring to the obj_table.
+ * @param available
+ * If non-NULL, returns the number of remaining ring entries after the
+ * dequeue has finished.
+ * @return
+ * - n: Actual number of objects dequeued, 0 if ring is empty
+ */
+static __rte_always_inline unsigned int
+rte_ring_mc_rts_v2_dequeue_burst_elem(struct rte_ring *r, void *obj_table,
+ unsigned int esize, unsigned int n, unsigned int *available)
+{
+ return __rte_ring_do_rts_v2_dequeue_elem(r, obj_table, esize, n,
+ RTE_RING_QUEUE_VARIABLE, available);
+}
+
/**
* Enqueue several objects on the RTS ring (multi-producers safe).
*
@@ -213,6 +323,52 @@ rte_ring_mc_rts_dequeue_bulk(struct rte_ring *r, void **obj_table,
sizeof(uintptr_t), n, available);
}
+/**
+ * Enqueue several objects on the RTS V2 ring (multi-producers safe).
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of void * pointers (objects).
+ * @param n
+ * The number of objects to add in the ring from the obj_table.
+ * @param free_space
+ * if non-NULL, returns the amount of space in the ring after the
+ * enqueue operation has finished.
+ * @return
+ * The number of objects enqueued, either 0 or n
+ */
+static __rte_always_inline unsigned int
+rte_ring_mp_rts_v2_enqueue_bulk(struct rte_ring *r, void * const *obj_table,
+ unsigned int n, unsigned int *free_space)
+{
+ return rte_ring_mp_rts_v2_enqueue_bulk_elem(r, obj_table,
+ sizeof(uintptr_t), n, free_space);
+}
+
+/**
+ * Dequeue several objects from an RTS V2 ring (multi-consumers safe).
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of void * pointers (objects) that will be filled.
+ * @param n
+ * The number of objects to dequeue from the ring to the obj_table.
+ * @param available
+ * If non-NULL, returns the number of remaining ring entries after the
+ * dequeue has finished.
+ * @return
+ * The number of objects dequeued, either 0 or n
+ */
+static __rte_always_inline unsigned int
+rte_ring_mc_rts_v2_dequeue_bulk(struct rte_ring *r, void **obj_table,
+ unsigned int n, unsigned int *available)
+{
+ return rte_ring_mc_rts_v2_dequeue_bulk_elem(r, obj_table,
+ sizeof(uintptr_t), n, available);
+}
+
/**
* Enqueue several objects on the RTS ring (multi-producers safe).
*
@@ -261,6 +417,54 @@ rte_ring_mc_rts_dequeue_burst(struct rte_ring *r, void **obj_table,
sizeof(uintptr_t), n, available);
}
+/**
+ * Enqueue several objects on the RTS V2 ring (multi-producers safe).
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of void * pointers (objects).
+ * @param n
+ * The number of objects to add in the ring from the obj_table.
+ * @param free_space
+ * if non-NULL, returns the amount of space in the ring after the
+ * enqueue operation has finished.
+ * @return
+ * - n: Actual number of objects enqueued.
+ */
+static __rte_always_inline unsigned int
+rte_ring_mp_rts_v2_enqueue_burst(struct rte_ring *r, void * const *obj_table,
+ unsigned int n, unsigned int *free_space)
+{
+ return rte_ring_mp_rts_v2_enqueue_burst_elem(r, obj_table,
+ sizeof(uintptr_t), n, free_space);
+}
+
+/**
+ * Dequeue several objects from an RTS V2 ring (multi-consumers safe).
+ * When the requested objects are more than the available objects,
+ * only dequeue the actual number of objects.
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of void * pointers (objects) that will be filled.
+ * @param n
+ * The number of objects to dequeue from the ring to the obj_table.
+ * @param available
+ * If non-NULL, returns the number of remaining ring entries after the
+ * dequeue has finished.
+ * @return
+ * - n: Actual number of objects dequeued, 0 if ring is empty
+ */
+static __rte_always_inline unsigned int
+rte_ring_mc_rts_v2_dequeue_burst(struct rte_ring *r, void **obj_table,
+ unsigned int n, unsigned int *available)
+{
+ return rte_ring_mc_rts_v2_dequeue_burst_elem(r, obj_table,
+ sizeof(uintptr_t), n, available);
+}
+
/**
* Return producer max Head-Tail-Distance (HTD).
*
@@ -273,7 +477,8 @@ rte_ring_mc_rts_dequeue_burst(struct rte_ring *r, void **obj_table,
static inline uint32_t
rte_ring_get_prod_htd_max(const struct rte_ring *r)
{
- if (r->prod.sync_type == RTE_RING_SYNC_MT_RTS)
+ if ((r->prod.sync_type == RTE_RING_SYNC_MT_RTS) ||
+ (r->prod.sync_type == RTE_RING_SYNC_MT_RTS_V2))
return r->rts_prod.htd_max;
return UINT32_MAX;
}
@@ -292,7 +497,8 @@ rte_ring_get_prod_htd_max(const struct rte_ring *r)
static inline int
rte_ring_set_prod_htd_max(struct rte_ring *r, uint32_t v)
{
- if (r->prod.sync_type != RTE_RING_SYNC_MT_RTS)
+ if ((r->prod.sync_type != RTE_RING_SYNC_MT_RTS) &&
+ (r->prod.sync_type != RTE_RING_SYNC_MT_RTS_V2))
return -ENOTSUP;
r->rts_prod.htd_max = v;
@@ -311,7 +517,8 @@ rte_ring_set_prod_htd_max(struct rte_ring *r, uint32_t v)
static inline uint32_t
rte_ring_get_cons_htd_max(const struct rte_ring *r)
{
- if (r->cons.sync_type == RTE_RING_SYNC_MT_RTS)
+ if ((r->cons.sync_type == RTE_RING_SYNC_MT_RTS) ||
+ (r->cons.sync_type == RTE_RING_SYNC_MT_RTS_V2))
return r->rts_cons.htd_max;
return UINT32_MAX;
}
@@ -330,7 +537,8 @@ rte_ring_get_cons_htd_max(const struct rte_ring *r)
static inline int
rte_ring_set_cons_htd_max(struct rte_ring *r, uint32_t v)
{
- if (r->cons.sync_type != RTE_RING_SYNC_MT_RTS)
+ if ((r->cons.sync_type != RTE_RING_SYNC_MT_RTS) &&
+ (r->cons.sync_type != RTE_RING_SYNC_MT_RTS_V2))
return -ENOTSUP;
r->rts_cons.htd_max = v;
diff --git a/lib/ring/rte_ring_rts_elem_pvt.h b/lib/ring/rte_ring_rts_elem_pvt.h
index 122650346b..4ce22a93ed 100644
--- a/lib/ring/rte_ring_rts_elem_pvt.h
+++ b/lib/ring/rte_ring_rts_elem_pvt.h
@@ -46,6 +46,92 @@ __rte_ring_rts_update_tail(struct rte_ring_rts_headtail *ht)
rte_memory_order_release, rte_memory_order_acquire) == 0);
}
+/**
+ * @file rte_ring_rts_elem_pvt.h
+ * It is not recommended to include this file directly,
+ * include <rte_ring.h> instead.
+ * Contains internal helper functions for Relaxed Tail Sync (RTS) ring mode.
+ * For more information please refer to <rte_ring_rts.h>.
+ */
+
+/**
+ * @internal This function updates tail values.
+ */
+static __rte_always_inline void
+__rte_ring_rts_v2_update_tail(struct rte_ring_rts_headtail *ht,
+ uint32_t old_tail, uint32_t num, uint32_t mask)
+{
+ union __rte_ring_rts_poscnt ot, nt;
+
+ ot.val.cnt = nt.val.cnt = 0;
+ ot.val.pos = old_tail;
+ nt.val.pos = old_tail + num;
+
+ /*
+ * If the tail is equal to the current enqueues/dequeues, update
+ * the tail with new value and then continue to try to update the
+ * tail until the num of the cache is 0, otherwise write the num of
+ * the current enqueues/dequeues to the cache.
+ */
+
+ if (rte_atomic_compare_exchange_strong_explicit(&ht->tail.raw,
+ (uint64_t *)(uintptr_t)&ot.raw, nt.raw,
+ rte_memory_order_release, rte_memory_order_acquire) == 0) {
+ ot.val.pos = old_tail;
+
+ /*
+ * Write the num of the current enqueues/dequeues to the
+ * corresponding cache.
+ */
+ rte_atomic_store_explicit(&ht->rts_cache[ot.val.pos & mask].num,
+ num, rte_memory_order_release);
+
+ /*
+ * There may be competition with another enqueues/dequeues
+ * for the update tail. The winner continues to try to update
+ * the tail, and the loser exits.
+ */
+ if (rte_atomic_compare_exchange_strong_explicit(&ht->tail.raw,
+ (uint64_t *)(uintptr_t)&ot.raw, nt.raw,
+ rte_memory_order_release, rte_memory_order_acquire) == 0)
+ return;
+
+ /*
+ * Set the corresponding cache to 0 for next use.
+ */
+ rte_atomic_store_explicit(&ht->rts_cache[ot.val.pos & mask].num,
+ 0, rte_memory_order_release);
+ }
+
+ /*
+ * Try to update the tail until the num of the corresponding cache is 0.
+ * Getting here means that the current enqueues/dequeues is trying to update
+ * the tail of another enqueues/dequeues.
+ */
+ while (1) {
+ num = rte_atomic_load_explicit(&ht->rts_cache[nt.val.pos & mask].num,
+ rte_memory_order_acquire);
+ if (num == 0)
+ break;
+
+ ot.val.pos = nt.val.pos;
+ nt.val.pos += num;
+
+ /*
+ * There may be competition with another enqueues/dequeues
+ * for the update tail. The winner continues to try to update
+ * the tail, and the loser exits.
+ */
+ if (rte_atomic_compare_exchange_strong_explicit(&ht->tail.raw,
+ (uint64_t *)(uintptr_t)&ot.raw, nt.raw,
+ rte_memory_order_release, rte_memory_order_acquire) == 0)
+ return;
+
+ rte_atomic_store_explicit(&ht->rts_cache[ot.val.pos & mask].num,
+ 0, rte_memory_order_release);
+ };
+}
+
/**
* @internal This function waits till head/tail distance wouldn't
* exceed pre-defined max value.
@@ -218,6 +304,47 @@ __rte_ring_do_rts_enqueue_elem(struct rte_ring *r, const void *obj_table,
return n;
}
+/**
+ * @internal Enqueue several objects on the RTS ring.
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of objects.
+ * @param esize
+ * The size of ring element, in bytes. It must be a multiple of 4.
+ * This must be the same value used while creating the ring. Otherwise
+ * the results are undefined.
+ * @param n
+ * The number of objects to add in the ring from the obj_table.
+ * @param behavior
+ * RTE_RING_QUEUE_FIXED: Enqueue a fixed number of items from a ring
+ * RTE_RING_QUEUE_VARIABLE: Enqueue as many items as possible from ring
+ * @param free_space
+ * returns the amount of space after the enqueue operation has finished
+ * @return
+ * Actual number of objects enqueued.
+ * If behavior == RTE_RING_QUEUE_FIXED, this will be 0 or n only.
+ */
+static __rte_always_inline unsigned int
+__rte_ring_do_rts_v2_enqueue_elem(struct rte_ring *r, const void *obj_table,
+ uint32_t esize, uint32_t n, enum rte_ring_queue_behavior behavior,
+ uint32_t *free_space)
+{
+ uint32_t free, head;
+
+ n = __rte_ring_rts_move_prod_head(r, n, behavior, &head, &free);
+
+ if (n != 0) {
+ __rte_ring_enqueue_elems(r, head, obj_table, esize, n);
+ __rte_ring_rts_v2_update_tail(&r->rts_prod, head, n, r->mask);
+ }
+
+ if (free_space != NULL)
+ *free_space = free - n;
+ return n;
+}
+
/**
* @internal Dequeue several objects from the RTS ring.
*
@@ -259,4 +386,45 @@ __rte_ring_do_rts_dequeue_elem(struct rte_ring *r, void *obj_table,
return n;
}
+/**
+ * @internal Dequeue several objects from the RTS ring.
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of objects.
+ * @param esize
+ * The size of ring element, in bytes. It must be a multiple of 4.
+ * This must be the same value used while creating the ring. Otherwise
+ * the results are undefined.
+ * @param n
+ * The number of objects to pull from the ring.
+ * @param behavior
+ * RTE_RING_QUEUE_FIXED: Dequeue a fixed number of items from a ring
+ * RTE_RING_QUEUE_VARIABLE: Dequeue as many items as possible from ring
+ * @param available
+ * returns the number of remaining ring entries after the dequeue has finished
+ * @return
+ * - Actual number of objects dequeued.
+ * If behavior == RTE_RING_QUEUE_FIXED, this will be 0 or n only.
+ */
+static __rte_always_inline unsigned int
+__rte_ring_do_rts_v2_dequeue_elem(struct rte_ring *r, void *obj_table,
+ uint32_t esize, uint32_t n, enum rte_ring_queue_behavior behavior,
+ uint32_t *available)
+{
+ uint32_t entries, head;
+
+ n = __rte_ring_rts_move_cons_head(r, n, behavior, &head, &entries);
+
+ if (n != 0) {
+ __rte_ring_dequeue_elems(r, head, obj_table, esize, n);
+ __rte_ring_rts_v2_update_tail(&r->rts_cons, head, n, r->mask);
+ }
+
+ if (available != NULL)
+ *available = entries - n;
+ return n;
+}
+
#endif /* _RTE_RING_RTS_ELEM_PVT_H_ */
--
2.27.0
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH v2] ring: add the second version of the RTS interface
2025-01-05 15:13 ` [PATCH v2] " Huichao Cai
@ 2025-01-08 1:41 ` Huichao Cai
2025-01-08 16:49 ` Konstantin Ananyev
1 sibling, 0 replies; 4+ messages in thread
From: Huichao Cai @ 2025-01-08 1:41 UTC (permalink / raw)
To: thomas; +Cc: dev, honnappa.nagarahalli, konstantin.v.ananyev
Hi,Thomas
This patch adds a field to the ABI structure.I have added the suppress_type
field in the file libabigail.abignore, but "ci/github-robot: Build" still reported
an error, could you please advise on how to fill in the suppress_type field?
^ permalink raw reply [flat|nested] 4+ messages in thread
* RE: [PATCH v2] ring: add the second version of the RTS interface
2025-01-05 15:13 ` [PATCH v2] " Huichao Cai
2025-01-08 1:41 ` Huichao Cai
@ 2025-01-08 16:49 ` Konstantin Ananyev
1 sibling, 0 replies; 4+ messages in thread
From: Konstantin Ananyev @ 2025-01-08 16:49 UTC (permalink / raw)
To: Huichao Cai, honnappa.nagarahalli, konstantin.v.ananyev, thomas; +Cc: dev
Hi,
> The timing of the update of the RTS enqueues/dequeues tail is
> limited to the last enqueues/dequeues, which reduces concurrency,
> so the RTS interface of the V2 version is added, which makes the tail
> of the enqueues/dequeues not limited to the last enqueues/dequeues
> and thus enables timely updates to increase concurrency.
That's description is way too cryptic to me and really just creates more confusion
instead of explain things: I have to go and read through the code to understand
what you are up to.
In fact, I don't think the approach you used will work properly dues to race
Conditions (see below for more details).
But for future reference, when you are introducing a new sync mechanism
for the ring please do:
1. explain clearly what particular problem(s) with existing one(s) you are trying to address.
2. clearly explain new sync mechanism you are going to introduce and why/when you believe
It would behave better than existing ones
3. In case of performance improvement claims - provide some reproducible numbers
either with ring_stress_test or some dpdk packet processing sample app or both.
> Add some corresponding test cases.
>
> Signed-off-by: Huichao Cai <chcchc88@163.com>
> ---
...
> diff --git a/lib/ring/rte_ring.c b/lib/ring/rte_ring.c
> index aebb6d6728..ada1ae88fa 100644
> --- a/lib/ring/rte_ring.c
> +++ b/lib/ring/rte_ring.c
> @@ -43,7 +43,8 @@ EAL_REGISTER_TAILQ(rte_ring_tailq)
> /* mask of all valid flag values to ring_create() */
> #define RING_F_MASK (RING_F_SP_ENQ | RING_F_SC_DEQ | RING_F_EXACT_SZ | \
> RING_F_MP_RTS_ENQ | RING_F_MC_RTS_DEQ | \
> - RING_F_MP_HTS_ENQ | RING_F_MC_HTS_DEQ)
> + RING_F_MP_HTS_ENQ | RING_F_MC_HTS_DEQ | \
> + RING_F_MP_RTS_V2_ENQ | RING_F_MC_RTS_V2_DEQ)
>
> /* true if x is a power of 2 */
> #define POWEROF2(x) ((((x)-1) & (x)) == 0)
> @@ -106,6 +107,7 @@ reset_headtail(void *p)
> ht->tail = 0;
> break;
> case RTE_RING_SYNC_MT_RTS:
> + case RTE_RING_SYNC_MT_RTS_V2:
> ht_rts->head.raw = 0;
> ht_rts->tail.raw = 0;
> break;
> @@ -135,9 +137,11 @@ get_sync_type(uint32_t flags, enum rte_ring_sync_type *prod_st,
> enum rte_ring_sync_type *cons_st)
> {
> static const uint32_t prod_st_flags =
> - (RING_F_SP_ENQ | RING_F_MP_RTS_ENQ | RING_F_MP_HTS_ENQ);
> + (RING_F_SP_ENQ | RING_F_MP_RTS_ENQ | RING_F_MP_HTS_ENQ |
> + RING_F_MP_RTS_V2_ENQ);
> static const uint32_t cons_st_flags =
> - (RING_F_SC_DEQ | RING_F_MC_RTS_DEQ | RING_F_MC_HTS_DEQ);
> + (RING_F_SC_DEQ | RING_F_MC_RTS_DEQ | RING_F_MC_HTS_DEQ |
> + RING_F_MC_RTS_V2_DEQ);
>
> switch (flags & prod_st_flags) {
> case 0:
> @@ -152,6 +156,9 @@ get_sync_type(uint32_t flags, enum rte_ring_sync_type *prod_st,
> case RING_F_MP_HTS_ENQ:
> *prod_st = RTE_RING_SYNC_MT_HTS;
> break;
> + case RING_F_MP_RTS_V2_ENQ:
> + *prod_st = RTE_RING_SYNC_MT_RTS_V2;
> + break;
> default:
> return -EINVAL;
> }
> @@ -169,6 +176,9 @@ get_sync_type(uint32_t flags, enum rte_ring_sync_type *prod_st,
> case RING_F_MC_HTS_DEQ:
> *cons_st = RTE_RING_SYNC_MT_HTS;
> break;
> + case RING_F_MC_RTS_V2_DEQ:
> + *cons_st = RTE_RING_SYNC_MT_RTS_V2;
> + break;
> default:
> return -EINVAL;
> }
> @@ -239,6 +249,28 @@ rte_ring_init(struct rte_ring *r, const char *name, unsigned int count,
> if (flags & RING_F_MC_RTS_DEQ)
> rte_ring_set_cons_htd_max(r, r->capacity / HTD_MAX_DEF);
>
> + /* set default values for head-tail distance and allocate memory to cache */
> + if (flags & RING_F_MP_RTS_V2_ENQ) {
> + rte_ring_set_prod_htd_max(r, r->capacity / HTD_MAX_DEF);
> + r->rts_prod.rts_cache = (struct rte_ring_rts_cache *)rte_zmalloc(
> + "RTS_PROD_CACHE", sizeof(struct rte_ring_rts_cache) * r->size, 0);
That doesn't look right at all - rte_ring_init() not supposed to allocate extra memory.
It is a caller responsibility to provide buffer large enough to hold whole ring (including
actual data and meta-data).
Ideally, if your sync mechanism needs extra space it should be reported by rte_ring_get_memsize_elem().
Though right now it takes only elem size and count...
One approach might be to introduce new function for that, another introduce new high-level struct,
instead of rte_ring.
Though I suppose first thing that needs to be done fix race-conditions and prove that such
addition is really worth from performance perspective.
> + if (r->rts_prod.rts_cache == NULL) {
> + RING_LOG(ERR, "Cannot reserve memory for rts prod cache");
> + return -ENOMEM;
> + }
> + }
> + if (flags & RING_F_MC_RTS_V2_DEQ) {
> + rte_ring_set_cons_htd_max(r, r->capacity / HTD_MAX_DEF);
> + r->rts_cons.rts_cache = (struct rte_ring_rts_cache *)rte_zmalloc(
> + "RTS_CONS_CACHE", sizeof(struct rte_ring_rts_cache) * r->size, 0);
> + if (r->rts_cons.rts_cache == NULL) {
> + if (flags & RING_F_MP_RTS_V2_ENQ)
> + rte_free(r->rts_prod.rts_cache);
> + RING_LOG(ERR, "Cannot reserve memory for rts cons cache");
> + return -ENOMEM;
> + }
> + }
> +
> return 0;
> }
>
....
> diff --git a/lib/ring/rte_ring_rts_elem_pvt.h b/lib/ring/rte_ring_rts_elem_pvt.h
> index 122650346b..4ce22a93ed 100644
> --- a/lib/ring/rte_ring_rts_elem_pvt.h
> +++ b/lib/ring/rte_ring_rts_elem_pvt.h
> @@ -46,6 +46,92 @@ __rte_ring_rts_update_tail(struct rte_ring_rts_headtail *ht)
> rte_memory_order_release, rte_memory_order_acquire) == 0);
> }
>
> +/**
> + * @file rte_ring_rts_elem_pvt.h
> + * It is not recommended to include this file directly,
> + * include <rte_ring.h> instead.
> + * Contains internal helper functions for Relaxed Tail Sync (RTS) ring mode.
> + * For more information please refer to <rte_ring_rts.h>.
> + */
> +
> +/**
> + * @internal This function updates tail values.
> + */
> +static __rte_always_inline void
> +__rte_ring_rts_v2_update_tail(struct rte_ring_rts_headtail *ht,
> + uint32_t old_tail, uint32_t num, uint32_t mask)
> +{
> + union __rte_ring_rts_poscnt ot, nt;
> +
> + ot.val.cnt = nt.val.cnt = 0;
> + ot.val.pos = old_tail;
> + nt.val.pos = old_tail + num;
> +
> + /*
> + * If the tail is equal to the current enqueues/dequeues, update
> + * the tail with new value and then continue to try to update the
> + * tail until the num of the cache is 0, otherwise write the num of
> + * the current enqueues/dequeues to the cache.
> + */
> +
> + if (rte_atomic_compare_exchange_strong_explicit(&ht->tail.raw,
> + (uint64_t *)(uintptr_t)&ot.raw, nt.raw,
> + rte_memory_order_release, rte_memory_order_acquire) == 0) {
> + ot.val.pos = old_tail;
> +
> + /*
> + * Write the num of the current enqueues/dequeues to the
> + * corresponding cache.
> + */
> + rte_atomic_store_explicit(&ht->rts_cache[ot.val.pos & mask].num,
> + num, rte_memory_order_release);
> +
> + /*
> + * There may be competition with another enqueues/dequeues
> + * for the update tail. The winner continues to try to update
> + * the tail, and the loser exits.
> + */
> + if (rte_atomic_compare_exchange_strong_explicit(&ht->tail.raw,
> + (uint64_t *)(uintptr_t)&ot.raw, nt.raw,
> + rte_memory_order_release, rte_memory_order_acquire) == 0)
> + return;
> +
> + /*
> + * Set the corresponding cache to 0 for next use.
> + */
I think there is race condition between CAS above and the store below:
After you updated the tail, other threads are free to re-use these ring elements.
So if some thread get stalled/preempted here while other threads will continue to do
enqueue/dequeue to the ring, this rts_cache[] element can be already re-used
by other thread when given thread will wake-up and overwrite it with zero.
In fact such race-condition can be easily reproduced on my box with:
echo ring_stress_autotest | dpdk-test --lcores=(2-16)@(3-5) -n 8 --no-pci --no-huge
all workers ends up in the infinite loop:
(gdb) bt
#0 _mm_pause ()
at /usr/lib64/gcc/x86_64-suse-linux/12/include/xmmintrin.h:1335
#1 rte_pause () at ../lib/eal/x86/include/rte_pause.h:18
#2 0x00000000010d008b in __rte_ring_rts_head_wait (h=0x7ff90c3ffca0,
ht=0x103ed2d40) at ../lib/ring/rte_ring_rts_elem_pvt.h:148
#3 __rte_ring_rts_move_prod_head (free_entries=0x7ff90c3ffcc8,
old_head=0x7ff90c3ffcc4, behavior=RTE_RING_QUEUE_FIXED, num=33,
r=0x103ed2cc0) at ../lib/ring/rte_ring_rts_elem_pvt.h:177
#4 __rte_ring_do_rts_v2_enqueue_elem (free_space=0x0,
behavior=RTE_RING_QUEUE_FIXED, n=33, esize=8, obj_table=0x7ff90c3ffec0,
r=0x103ed2cc0) at ../lib/ring/rte_ring_rts_elem_pvt.h:336
#5 rte_ring_mp_rts_v2_enqueue_bulk_elem (free_space=0x0, n=33, esize=8,
obj_table=0x7ff90c3ffec0, r=0x103ed2cc0) at ../lib/ring/rte_ring_rts.h:110
#6 rte_ring_mp_rts_v2_enqueue_bulk (free_space=0x0, n=33,
obj_table=0x7ff90c3ffec0, r=0x103ed2cc0) at ../lib/ring/rte_ring_rts.h:345
#7 _st_ring_enqueue_bulk (r=0x103ed2cc0, obj=0x7ff90c3ffec0, n=33, free=0x0)
at ../app/test/test_ring_rts_v2_stress.c:18
....
(gdb) print/x r->rts_prod.rts_cache[r->rts_prod.tail.val.pos & r->mask]
$11 = {num = 0x0}
(gdb) print r->rts_prod
$13 = {tail = {raw = 127384228873633792, val = {cnt = 0, pos = 29658952}},
sync_type = RTE_RING_SYNC_MT_RTS_V2, htd_max = 2047, head = {
raw = 127393072212139551, val = {cnt = 843295, pos = 29661011}},
rts_cache = 0x103ec2c40}
(gdb) print 29661011-29658952
$14 = 2059
All in all - I don't think this approach is going to work.
You need some extra stuff to synchronize between cache[] and tail.
If interested, in SORING we solved similar thing by updating state[] before updating tail,
plus making sure that only one thread at a time will update tail value:
https://patchwork.dpdk.org/project/dpdk/patch/20241206183600.34758-6-konstantin.ananyev@huawei.com/
Another minor thing - why do you re-use RTS head/tail struct?
From what I can read you don't .cnt part at all.
> + rte_atomic_store_explicit(&ht->rts_cache[ot.val.pos & mask].num,
> + 0, rte_memory_order_release);
> + }
> +
> + /*
> + * Try to update the tail until the num of the corresponding cache is 0.
> + * Getting here means that the current enqueues/dequeues is trying to update
> + * the tail of another enqueues/dequeues.
> + */
> + while (1) {
> + num = rte_atomic_load_explicit(&ht->rts_cache[nt.val.pos & mask].num,
> + rte_memory_order_acquire);
> + if (num == 0)
> + break;
> +
> + ot.val.pos = nt.val.pos;
> + nt.val.pos += num;
> +
> + /*
> + * There may be competition with another enqueues/dequeues
> + * for the update tail. The winner continues to try to update
> + * the tail, and the loser exits.
> + */
> + if (rte_atomic_compare_exchange_strong_explicit(&ht->tail.raw,
> + (uint64_t *)(uintptr_t)&ot.raw, nt.raw,
> + rte_memory_order_release, rte_memory_order_acquire) == 0)
> + return;
> +
> + rte_atomic_store_explicit(&ht->rts_cache[ot.val.pos & mask].num,
> + 0, rte_memory_order_release);
> + };
> +}
> +
^ permalink raw reply [flat|nested] 4+ messages in thread
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2025-01-05 15:09 [PATCH v2] ring: add the second version of the RTS interface Huichao Cai
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2025-01-05 9:57 [PATCH] " Huichao Cai
2025-01-05 15:13 ` [PATCH v2] " Huichao Cai
2025-01-08 1:41 ` Huichao Cai
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