[v3,7/9] ring: introduce peek style API
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Commit Message
For rings with producer/consumer in RTE_RING_SYNC_ST, RTE_RING_SYNC_MT_HTS
mode, provide an ability to split enqueue/dequeue operation
into two phases:
- enqueue/dequeue start
- enqueue/dequeue finish
That allows user to inspect objects in the ring without removing
them from it (aka MT safe peek).
Signed-off-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
---
lib/librte_ring/Makefile | 1 +
lib/librte_ring/meson.build | 1 +
lib/librte_ring/rte_ring_c11_mem.h | 44 +++
lib/librte_ring/rte_ring_elem.h | 4 +
lib/librte_ring/rte_ring_generic.h | 48 ++++
lib/librte_ring/rte_ring_hts_generic.h | 47 ++-
lib/librte_ring/rte_ring_peek.h | 379 +++++++++++++++++++++++++
7 files changed, 519 insertions(+), 5 deletions(-)
create mode 100644 lib/librte_ring/rte_ring_peek.h
Comments
<snip>
>
> For rings with producer/consumer in RTE_RING_SYNC_ST,
> RTE_RING_SYNC_MT_HTS mode, provide an ability to split enqueue/dequeue
> operation into two phases:
> - enqueue/dequeue start
> - enqueue/dequeue finish
> That allows user to inspect objects in the ring without removing them from it
> (aka MT safe peek).
>
> Signed-off-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
> ---
> lib/librte_ring/Makefile | 1 +
> lib/librte_ring/meson.build | 1 +
> lib/librte_ring/rte_ring_c11_mem.h | 44 +++
> lib/librte_ring/rte_ring_elem.h | 4 +
> lib/librte_ring/rte_ring_generic.h | 48 ++++
> lib/librte_ring/rte_ring_hts_generic.h | 47 ++-
> lib/librte_ring/rte_ring_peek.h | 379 +++++++++++++++++++++++++
> 7 files changed, 519 insertions(+), 5 deletions(-) create mode 100644
> lib/librte_ring/rte_ring_peek.h
>
> diff --git a/lib/librte_ring/Makefile b/lib/librte_ring/Makefile index
> 6fe500f0d..5f8662737 100644
> --- a/lib/librte_ring/Makefile
> +++ b/lib/librte_ring/Makefile
> @@ -22,6 +22,7 @@ SYMLINK-$(CONFIG_RTE_LIBRTE_RING)-include :=
> rte_ring.h \
> rte_ring_hts.h \
> rte_ring_hts_elem.h \
> rte_ring_hts_generic.h \
> + rte_ring_peek.h \
> rte_ring_rts.h \
> rte_ring_rts_elem.h \
> rte_ring_rts_generic.h
> diff --git a/lib/librte_ring/meson.build b/lib/librte_ring/meson.build index
> 8e86e037a..f5f84dc6e 100644
> --- a/lib/librte_ring/meson.build
> +++ b/lib/librte_ring/meson.build
> @@ -9,6 +9,7 @@ headers = files('rte_ring.h',
> 'rte_ring_hts.h',
> 'rte_ring_hts_elem.h',
> 'rte_ring_hts_generic.h',
> + 'rte_ring_peek.h',
> 'rte_ring_rts.h',
> 'rte_ring_rts_elem.h',
> 'rte_ring_rts_generic.h')
> diff --git a/lib/librte_ring/rte_ring_c11_mem.h
> b/lib/librte_ring/rte_ring_c11_mem.h
> index 0fb73a337..bb3096721 100644
> --- a/lib/librte_ring/rte_ring_c11_mem.h
> +++ b/lib/librte_ring/rte_ring_c11_mem.h
> @@ -10,6 +10,50 @@
> #ifndef _RTE_RING_C11_MEM_H_
> #define _RTE_RING_C11_MEM_H_
>
> +/**
> + * @internal get current tail value.
> + * This function should be used only for single thread producer/consumer.
> + * Check that user didn't request to move tail above the head.
Do we need this check? This could be a data path function, we could document a warning and leave it to the users to provide the correct value.
> + * In that situation:
> + * - return zero, that will cause abort any pending changes and
> + * return head to its previous position.
> + * - throw an assert in debug mode.
> + */
> +static __rte_always_inline uint32_t
> +__rte_ring_st_get_tail(struct rte_ring_headtail *ht, uint32_t *tail,
> + uint32_t num)
> +{
> + uint32_t h, n, t;
> +
> + h = ht->head;
> + t = ht->tail;
> + n = h - t;
> +
> + RTE_ASSERT(n >= num);
> + num = (n >= num) ? num : 0;
> +
> + *tail = h;
> + return num;
> +}
> +
> +/**
> + * @internal set new values for head and tail.
> + * This function should be used only for single thread producer/consumer.
> + * Should be used only in conjunction with __rte_ring_st_get_tail.
> + */
> +static __rte_always_inline void
> +__rte_ring_st_set_head_tail(struct rte_ring_headtail *ht, uint32_t tail,
> + uint32_t num, uint32_t enqueue)
> +{
> + uint32_t pos;
> +
> + RTE_SET_USED(enqueue);
> +
> + pos = tail + num;
> + ht->head = pos;
> + __atomic_store_n(&ht->tail, pos, __ATOMIC_RELEASE); }
> +
> static __rte_always_inline void
> update_tail(struct rte_ring_headtail *ht, uint32_t old_val, uint32_t new_val,
> uint32_t single, uint32_t enqueue)
> diff --git a/lib/librte_ring/rte_ring_elem.h b/lib/librte_ring/rte_ring_elem.h
> index 010a564c1..5bf7c1c1b 100644
> --- a/lib/librte_ring/rte_ring_elem.h
> +++ b/lib/librte_ring/rte_ring_elem.h
> @@ -1083,6 +1083,10 @@ rte_ring_dequeue_burst_elem(struct rte_ring *r,
> void *obj_table,
> return 0;
> }
>
> +#ifdef ALLOW_EXPERIMENTAL_API
> +#include <rte_ring_peek.h>
> +#endif
> +
> #ifdef __cplusplus
> }
> #endif
> diff --git a/lib/librte_ring/rte_ring_generic.h
> b/lib/librte_ring/rte_ring_generic.h
> index 953cdbbd5..9f5fdf13b 100644
> --- a/lib/librte_ring/rte_ring_generic.h
> +++ b/lib/librte_ring/rte_ring_generic.h
> @@ -10,6 +10,54 @@
> #ifndef _RTE_RING_GENERIC_H_
> #define _RTE_RING_GENERIC_H_
>
> +/**
> + * @internal get current tail value.
> + * This function should be used only for single thread producer/consumer.
> + * Check that user didn't request to move tail above the head.
> + * In that situation:
> + * - return zero, that will cause abort any pending changes and
> + * return head to its previous position.
> + * - throw an assert in debug mode.
> + */
> +static __rte_always_inline uint32_t
> +__rte_ring_st_get_tail(struct rte_ring_headtail *ht, uint32_t *tail,
> + uint32_t num)
> +{
> + uint32_t h, n, t;
> +
> + h = ht->head;
> + t = ht->tail;
> + n = h - t;
> +
> + RTE_ASSERT(n >= num);
> + num = (n >= num) ? num : 0;
> +
> + *tail = h;
> + return num;
> +}
> +
> +/**
> + * @internal set new values for head and tail.
> + * This function should be used only for single thread producer/consumer.
> + * Should be used only in conjunction with __rte_ring_st_get_tail.
> + */
> +static __rte_always_inline void
> +__rte_ring_st_set_head_tail(struct rte_ring_headtail *ht, uint32_t tail,
> + uint32_t num, uint32_t enqueue)
> +{
> + uint32_t pos;
> +
> + pos = tail + num;
> +
> + if (enqueue)
> + rte_smp_wmb();
> + else
> + rte_smp_rmb();
> +
> + ht->head = pos;
> + ht->tail = pos;
> +}
> +
> static __rte_always_inline void
> update_tail(struct rte_ring_headtail *ht, uint32_t old_val, uint32_t new_val,
> uint32_t single, uint32_t enqueue)
> diff --git a/lib/librte_ring/rte_ring_hts_generic.h
> b/lib/librte_ring/rte_ring_hts_generic.h
> index da08f1d94..8e699c006 100644
> --- a/lib/librte_ring/rte_ring_hts_generic.h
> +++ b/lib/librte_ring/rte_ring_hts_generic.h
> @@ -18,9 +18,38 @@
> * For more information please refer to <rte_ring_hts.h>.
> */
>
> +/**
> + * @internal get current tail value.
> + * Check that user didn't request to move tail above the head.
> + * In that situation:
> + * - return zero, that will cause abort any pending changes and
> + * return head to its previous position.
> + * - throw an assert in debug mode.
> + */
> +static __rte_always_inline uint32_t
> +__rte_ring_hts_get_tail(struct rte_ring_hts_headtail *ht, uint32_t *tail,
> + uint32_t num)
> +{
> + uint32_t n;
> + union rte_ring_ht_pos p;
> +
> + p.raw = rte_atomic64_read((rte_atomic64_t *)(uintptr_t)&ht-
> >ht.raw);
> + n = p.pos.head - p.pos.tail;
> +
> + RTE_ASSERT(n >= num);
> + num = (n >= num) ? num : 0;
> +
> + *tail = p.pos.tail;
> + return num;
> +}
> +
> +/**
> + * @internal set new values for head and tail as one atomic 64 bit operation.
> + * Should be used only in conjunction with __rte_ring_hts_get_tail.
> + */
> static __rte_always_inline void
> -__rte_ring_hts_update_tail(struct rte_ring_hts_headtail *ht, uint32_t num,
> - uint32_t enqueue)
> +__rte_ring_hts_set_head_tail(struct rte_ring_hts_headtail *ht, uint32_t tail,
> + uint32_t num, uint32_t enqueue)
> {
> union rte_ring_ht_pos p;
>
> @@ -29,14 +58,22 @@ __rte_ring_hts_update_tail(struct
> rte_ring_hts_headtail *ht, uint32_t num,
> else
> rte_smp_rmb();
>
> - p.raw = rte_atomic64_read((rte_atomic64_t *)(uintptr_t)&ht-
> >ht.raw);
> -
> - p.pos.head = p.pos.tail + num;
> + p.pos.head = tail + num;
> p.pos.tail = p.pos.head;
>
> rte_atomic64_set((rte_atomic64_t *)(uintptr_t)&ht->ht.raw, p.raw); }
>
> +static __rte_always_inline void
> +__rte_ring_hts_update_tail(struct rte_ring_hts_headtail *ht, uint32_t num,
> + uint32_t enqueue)
> +{
> + uint32_t tail;
> +
> + num = __rte_ring_hts_get_tail(ht, &tail, num);
> + __rte_ring_hts_set_head_tail(ht, tail, num, enqueue); }
> +
> /**
> * @internal waits till tail will become equal to head.
> * Means no writer/reader is active for that ring.
> diff --git a/lib/librte_ring/rte_ring_peek.h b/lib/librte_ring/rte_ring_peek.h
> new file mode 100644 index 000000000..baefd2f7b
> --- /dev/null
> +++ b/lib/librte_ring/rte_ring_peek.h
> @@ -0,0 +1,379 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + *
> + * Copyright (c) 2010-2017 Intel Corporation
> + * Copyright (c) 2007-2009 Kip Macy kmacy@freebsd.org
> + * All rights reserved.
> + * Derived from FreeBSD's bufring.h
> + * Used as BSD-3 Licensed with permission from Kip Macy.
> + */
> +
> +#ifndef _RTE_RING_PEEK_H_
> +#define _RTE_RING_PEEK_H_
> +
> +/**
> + * @file
> + * @b EXPERIMENTAL: this API may change without prior notice
> + * It is not recommended to include this file directly.
> + * Please include <rte_ring_elem.h> instead.
> + *
> + * Ring Peek AP
^^^ API
> + * Introduction of rte_ring with serialized producer/consumer (HTS sync
> +mode)
> + * makes possible to split public enqueue/dequeue API into two phases:
> + * - enqueue/dequeue start
> + * - enqueue/dequeue finish
> + * That allows user to inspect objects in the ring without removing
> +them
> + * from it (aka MT safe peek).
> + * Note that right now this new API is avaialble only for two sync modes:
> + * 1) Single Producer/Single Consumer (RTE_RING_SYNC_ST)
> + * 2) Serialized Producer/Serialized Consumer (RTE_RING_SYNC_MT_HTS).
> + * It is a user responsibility to create/init ring with appropriate
> +sync
> + * modes selected.
> + * As an example:
> + * // read 1 elem from the ring:
> + * n = rte_ring_hts_dequeue_bulk_start(ring, &obj, 1, NULL);
> + * if (n != 0) {
> + * //examine object
> + * if (object_examine(obj) == KEEP)
> + * //decided to keep it in the ring.
> + * rte_ring_hts_dequeue_finish(ring, 0);
> + * else
> + * //decided to remove it from the ring.
> + * rte_ring_hts_dequeue_finish(ring, n);
> + * }
> + * Note that between _start_ and _finish_ the ring is sort of locked -
^^^^^^^^^^^^^^^^^^^^ - 'locked' can mean different to different people, may be remove this, the next sentence anyway has the description
> + * none other thread can proceed with enqueue(/dequeue) operation till
^^^^ no
> + * _finish_ will complete.
^^^^^^^^^^^ completes
> + */
> +
> +#ifdef __cplusplus
> +extern "C" {
> +#endif
> +
<snip>
> +
> +/**
> + * Start to enqueue several objects on the ring.
> + * Note that no actual objects are put in the queue by this function,
> + * it just reserves for user such ability.
> + * User has to call appropriate enqueue_finish() to copy objects into
> +the
> + * queue and complete given enqueue operation.
> + *
> + * @param r
> + * A pointer to the ring structure.
> + * @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 that can be enqueued, either 0 or n
> + */
> +__rte_experimental
> +static __rte_always_inline unsigned int
> +rte_ring_enqueue_bulk_start(struct rte_ring *r, unsigned int n,
> + unsigned int *free_space)
If one wants to use _elem_ APIs for ring peek, a combination of legacy API (format) and a _elem_ API is required.
For ex:
rte_ring_enqueue_bulk_start
rte_ring_enqueue_elem_finish
I understand why you have done this. I think this is getting somewhat too inconsistent.
> +{
> + return __rte_ring_do_enqueue_start(r, n, RTE_RING_QUEUE_FIXED,
> + free_space);
> +}
> +
<snip>
> +
> +/**
> + * Start to dequeue several objects from the ring.
> + * Note that user has to call appropriate dequeue_finish()
> + * to complete given dequeue operation and actually remove objects the ring.
> + *
> + * @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 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
> + * Actual number of objects dequeued.
> + */
> +__rte_experimental
> +static __rte_always_inline unsigned int
> +rte_ring_dequeue_bulk_start(struct rte_ring *r, void **obj_table,
> + unsigned int n, unsigned int *available) {
Should this in a separate file? (similar to rte_ring.h and rte_ring_elem.h)
> + return rte_ring_dequeue_bulk_elem_start(r, obj_table,
> sizeof(uintptr_t),
> + n, available);
> +}
> +
> +/**
> + * Start to dequeue several objects from the ring.
> + * Note that user has to call appropriate dequeue_finish()
> + * to complete given dequeue operation and actually remove objects the ring.
> + *
> + * @param r
> + * A pointer to the ring structure.
> + * @param obj_table
> + * A pointer to a table of void * pointers (objects) that will be filled.
Minor, update this to indicate generic objects. Can be copied from rte_ring_elem.h.
> + * @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 actual number of objects dequeued.
> + */
> +__rte_experimental
> +static __rte_always_inline unsigned int
> +rte_ring_dequeue_burst_elem_start(struct rte_ring *r, void **obj_table,
> + unsigned int esize, unsigned int n, unsigned int *available) {
> + return __rte_ring_do_dequeue_start(r, obj_table, esize, n,
> + RTE_RING_QUEUE_VARIABLE, available); }
> +
<snip>
> +
> +#ifdef __cplusplus
> +}
> +#endif
> +
> +#endif /* _RTE_RING_PEEK_H_ */
> --
> 2.17.1
> >
> > For rings with producer/consumer in RTE_RING_SYNC_ST,
> > RTE_RING_SYNC_MT_HTS mode, provide an ability to split enqueue/dequeue
> > operation into two phases:
> > - enqueue/dequeue start
> > - enqueue/dequeue finish
> > That allows user to inspect objects in the ring without removing them from it
> > (aka MT safe peek).
> >
> > Signed-off-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
> > ---
> > lib/librte_ring/Makefile | 1 +
> > lib/librte_ring/meson.build | 1 +
> > lib/librte_ring/rte_ring_c11_mem.h | 44 +++
> > lib/librte_ring/rte_ring_elem.h | 4 +
> > lib/librte_ring/rte_ring_generic.h | 48 ++++
> > lib/librte_ring/rte_ring_hts_generic.h | 47 ++-
> > lib/librte_ring/rte_ring_peek.h | 379 +++++++++++++++++++++++++
> > 7 files changed, 519 insertions(+), 5 deletions(-) create mode 100644
> > lib/librte_ring/rte_ring_peek.h
> >
> > diff --git a/lib/librte_ring/Makefile b/lib/librte_ring/Makefile index
> > 6fe500f0d..5f8662737 100644
> > --- a/lib/librte_ring/Makefile
> > +++ b/lib/librte_ring/Makefile
> > @@ -22,6 +22,7 @@ SYMLINK-$(CONFIG_RTE_LIBRTE_RING)-include :=
> > rte_ring.h \
> > rte_ring_hts.h \
> > rte_ring_hts_elem.h \
> > rte_ring_hts_generic.h \
> > + rte_ring_peek.h \
> > rte_ring_rts.h \
> > rte_ring_rts_elem.h \
> > rte_ring_rts_generic.h
> > diff --git a/lib/librte_ring/meson.build b/lib/librte_ring/meson.build index
> > 8e86e037a..f5f84dc6e 100644
> > --- a/lib/librte_ring/meson.build
> > +++ b/lib/librte_ring/meson.build
> > @@ -9,6 +9,7 @@ headers = files('rte_ring.h',
> > 'rte_ring_hts.h',
> > 'rte_ring_hts_elem.h',
> > 'rte_ring_hts_generic.h',
> > + 'rte_ring_peek.h',
> > 'rte_ring_rts.h',
> > 'rte_ring_rts_elem.h',
> > 'rte_ring_rts_generic.h')
> > diff --git a/lib/librte_ring/rte_ring_c11_mem.h
> > b/lib/librte_ring/rte_ring_c11_mem.h
> > index 0fb73a337..bb3096721 100644
> > --- a/lib/librte_ring/rte_ring_c11_mem.h
> > +++ b/lib/librte_ring/rte_ring_c11_mem.h
> > @@ -10,6 +10,50 @@
> > #ifndef _RTE_RING_C11_MEM_H_
> > #define _RTE_RING_C11_MEM_H_
> >
> > +/**
> > + * @internal get current tail value.
> > + * This function should be used only for single thread producer/consumer.
> > + * Check that user didn't request to move tail above the head.
> Do we need this check? This could be a data path function, we could document a warning and leave it to the users to provide the correct
> value.
I don't think this extra check will cause any extra slowdown.
From other side, it seems useful to have it - might help people
to debug/root-cause an issue.
> > + * In that situation:
> > + * - return zero, that will cause abort any pending changes and
> > + * return head to its previous position.
> > + * - throw an assert in debug mode.
> > + */
> > +static __rte_always_inline uint32_t
> > +__rte_ring_st_get_tail(struct rte_ring_headtail *ht, uint32_t *tail,
> > + uint32_t num)
> > +{
> > + uint32_t h, n, t;
> > +
> > + h = ht->head;
> > + t = ht->tail;
> > + n = h - t;
> > +
> > + RTE_ASSERT(n >= num);
> > + num = (n >= num) ? num : 0;
> > +
> > + *tail = h;
> > + return num;
> > +}
> > +
> > +/**
> > + * @internal set new values for head and tail.
> > + * This function should be used only for single thread producer/consumer.
> > + * Should be used only in conjunction with __rte_ring_st_get_tail.
> > + */
> > +static __rte_always_inline void
> > +__rte_ring_st_set_head_tail(struct rte_ring_headtail *ht, uint32_t tail,
> > + uint32_t num, uint32_t enqueue)
> > +{
> > + uint32_t pos;
> > +
> > + RTE_SET_USED(enqueue);
> > +
> > + pos = tail + num;
> > + ht->head = pos;
> > + __atomic_store_n(&ht->tail, pos, __ATOMIC_RELEASE); }
> > +
> > static __rte_always_inline void
> > update_tail(struct rte_ring_headtail *ht, uint32_t old_val, uint32_t new_val,
> > uint32_t single, uint32_t enqueue)
> > diff --git a/lib/librte_ring/rte_ring_elem.h b/lib/librte_ring/rte_ring_elem.h
> > index 010a564c1..5bf7c1c1b 100644
> > --- a/lib/librte_ring/rte_ring_elem.h
> > +++ b/lib/librte_ring/rte_ring_elem.h
> > @@ -1083,6 +1083,10 @@ rte_ring_dequeue_burst_elem(struct rte_ring *r,
> > void *obj_table,
> > return 0;
> > }
> >
> > +#ifdef ALLOW_EXPERIMENTAL_API
> > +#include <rte_ring_peek.h>
> > +#endif
> > +
> > #ifdef __cplusplus
> > }
> > #endif
> > diff --git a/lib/librte_ring/rte_ring_generic.h
> > b/lib/librte_ring/rte_ring_generic.h
> > index 953cdbbd5..9f5fdf13b 100644
> > --- a/lib/librte_ring/rte_ring_generic.h
> > +++ b/lib/librte_ring/rte_ring_generic.h
> > @@ -10,6 +10,54 @@
> > #ifndef _RTE_RING_GENERIC_H_
> > #define _RTE_RING_GENERIC_H_
> >
> > +/**
> > + * @internal get current tail value.
> > + * This function should be used only for single thread producer/consumer.
> > + * Check that user didn't request to move tail above the head.
> > + * In that situation:
> > + * - return zero, that will cause abort any pending changes and
> > + * return head to its previous position.
> > + * - throw an assert in debug mode.
> > + */
> > +static __rte_always_inline uint32_t
> > +__rte_ring_st_get_tail(struct rte_ring_headtail *ht, uint32_t *tail,
> > + uint32_t num)
> > +{
> > + uint32_t h, n, t;
> > +
> > + h = ht->head;
> > + t = ht->tail;
> > + n = h - t;
> > +
> > + RTE_ASSERT(n >= num);
> > + num = (n >= num) ? num : 0;
> > +
> > + *tail = h;
> > + return num;
> > +}
> > +
> > +/**
> > + * @internal set new values for head and tail.
> > + * This function should be used only for single thread producer/consumer.
> > + * Should be used only in conjunction with __rte_ring_st_get_tail.
> > + */
> > +static __rte_always_inline void
> > +__rte_ring_st_set_head_tail(struct rte_ring_headtail *ht, uint32_t tail,
> > + uint32_t num, uint32_t enqueue)
> > +{
> > + uint32_t pos;
> > +
> > + pos = tail + num;
> > +
> > + if (enqueue)
> > + rte_smp_wmb();
> > + else
> > + rte_smp_rmb();
> > +
> > + ht->head = pos;
> > + ht->tail = pos;
> > +}
> > +
> > static __rte_always_inline void
> > update_tail(struct rte_ring_headtail *ht, uint32_t old_val, uint32_t new_val,
> > uint32_t single, uint32_t enqueue)
> > diff --git a/lib/librte_ring/rte_ring_hts_generic.h
> > b/lib/librte_ring/rte_ring_hts_generic.h
> > index da08f1d94..8e699c006 100644
> > --- a/lib/librte_ring/rte_ring_hts_generic.h
> > +++ b/lib/librte_ring/rte_ring_hts_generic.h
> > @@ -18,9 +18,38 @@
> > * For more information please refer to <rte_ring_hts.h>.
> > */
> >
> > +/**
> > + * @internal get current tail value.
> > + * Check that user didn't request to move tail above the head.
> > + * In that situation:
> > + * - return zero, that will cause abort any pending changes and
> > + * return head to its previous position.
> > + * - throw an assert in debug mode.
> > + */
> > +static __rte_always_inline uint32_t
> > +__rte_ring_hts_get_tail(struct rte_ring_hts_headtail *ht, uint32_t *tail,
> > + uint32_t num)
> > +{
> > + uint32_t n;
> > + union rte_ring_ht_pos p;
> > +
> > + p.raw = rte_atomic64_read((rte_atomic64_t *)(uintptr_t)&ht-
> > >ht.raw);
> > + n = p.pos.head - p.pos.tail;
> > +
> > + RTE_ASSERT(n >= num);
> > + num = (n >= num) ? num : 0;
> > +
> > + *tail = p.pos.tail;
> > + return num;
> > +}
> > +
> > +/**
> > + * @internal set new values for head and tail as one atomic 64 bit operation.
> > + * Should be used only in conjunction with __rte_ring_hts_get_tail.
> > + */
> > static __rte_always_inline void
> > -__rte_ring_hts_update_tail(struct rte_ring_hts_headtail *ht, uint32_t num,
> > - uint32_t enqueue)
> > +__rte_ring_hts_set_head_tail(struct rte_ring_hts_headtail *ht, uint32_t tail,
> > + uint32_t num, uint32_t enqueue)
> > {
> > union rte_ring_ht_pos p;
> >
> > @@ -29,14 +58,22 @@ __rte_ring_hts_update_tail(struct
> > rte_ring_hts_headtail *ht, uint32_t num,
> > else
> > rte_smp_rmb();
> >
> > - p.raw = rte_atomic64_read((rte_atomic64_t *)(uintptr_t)&ht-
> > >ht.raw);
> > -
> > - p.pos.head = p.pos.tail + num;
> > + p.pos.head = tail + num;
> > p.pos.tail = p.pos.head;
> >
> > rte_atomic64_set((rte_atomic64_t *)(uintptr_t)&ht->ht.raw, p.raw); }
> >
> > +static __rte_always_inline void
> > +__rte_ring_hts_update_tail(struct rte_ring_hts_headtail *ht, uint32_t num,
> > + uint32_t enqueue)
> > +{
> > + uint32_t tail;
> > +
> > + num = __rte_ring_hts_get_tail(ht, &tail, num);
> > + __rte_ring_hts_set_head_tail(ht, tail, num, enqueue); }
> > +
> > /**
> > * @internal waits till tail will become equal to head.
> > * Means no writer/reader is active for that ring.
> > diff --git a/lib/librte_ring/rte_ring_peek.h b/lib/librte_ring/rte_ring_peek.h
> > new file mode 100644 index 000000000..baefd2f7b
> > --- /dev/null
> > +++ b/lib/librte_ring/rte_ring_peek.h
> > @@ -0,0 +1,379 @@
> > +/* SPDX-License-Identifier: BSD-3-Clause
> > + *
> > + * Copyright (c) 2010-2017 Intel Corporation
> > + * Copyright (c) 2007-2009 Kip Macy kmacy@freebsd.org
> > + * All rights reserved.
> > + * Derived from FreeBSD's bufring.h
> > + * Used as BSD-3 Licensed with permission from Kip Macy.
> > + */
> > +
> > +#ifndef _RTE_RING_PEEK_H_
> > +#define _RTE_RING_PEEK_H_
> > +
> > +/**
> > + * @file
> > + * @b EXPERIMENTAL: this API may change without prior notice
> > + * It is not recommended to include this file directly.
> > + * Please include <rte_ring_elem.h> instead.
> > + *
> > + * Ring Peek AP
> ^^^ API
> > + * Introduction of rte_ring with serialized producer/consumer (HTS sync
> > +mode)
> > + * makes possible to split public enqueue/dequeue API into two phases:
> > + * - enqueue/dequeue start
> > + * - enqueue/dequeue finish
> > + * That allows user to inspect objects in the ring without removing
> > +them
> > + * from it (aka MT safe peek).
> > + * Note that right now this new API is avaialble only for two sync modes:
> > + * 1) Single Producer/Single Consumer (RTE_RING_SYNC_ST)
> > + * 2) Serialized Producer/Serialized Consumer (RTE_RING_SYNC_MT_HTS).
> > + * It is a user responsibility to create/init ring with appropriate
> > +sync
> > + * modes selected.
> > + * As an example:
> > + * // read 1 elem from the ring:
> > + * n = rte_ring_hts_dequeue_bulk_start(ring, &obj, 1, NULL);
> > + * if (n != 0) {
> > + * //examine object
> > + * if (object_examine(obj) == KEEP)
> > + * //decided to keep it in the ring.
> > + * rte_ring_hts_dequeue_finish(ring, 0);
> > + * else
> > + * //decided to remove it from the ring.
> > + * rte_ring_hts_dequeue_finish(ring, n);
> > + * }
> > + * Note that between _start_ and _finish_ the ring is sort of locked -
> ^^^^^^^^^^^^^^^^^^^^ - 'locked' can mean different to different people, may be remove this,
> the next sentence anyway has the description
> > + * none other thread can proceed with enqueue(/dequeue) operation till
> ^^^^ no
> > + * _finish_ will complete.
> ^^^^^^^^^^^ completes
> > + */
> > +
> > +#ifdef __cplusplus
> > +extern "C" {
> > +#endif
> > +
>
> <snip>
>
> > +
> > +/**
> > + * Start to enqueue several objects on the ring.
> > + * Note that no actual objects are put in the queue by this function,
> > + * it just reserves for user such ability.
> > + * User has to call appropriate enqueue_finish() to copy objects into
> > +the
> > + * queue and complete given enqueue operation.
> > + *
> > + * @param r
> > + * A pointer to the ring structure.
> > + * @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 that can be enqueued, either 0 or n
> > + */
> > +__rte_experimental
> > +static __rte_always_inline unsigned int
> > +rte_ring_enqueue_bulk_start(struct rte_ring *r, unsigned int n,
> > + unsigned int *free_space)
> If one wants to use _elem_ APIs for ring peek, a combination of legacy API (format) and a _elem_ API is required.
> For ex:
> rte_ring_enqueue_bulk_start
> rte_ring_enqueue_elem_finish
>
> I understand why you have done this. I think this is getting somewhat too inconsistent.
>
Agree, there could be some confusion.
Don't know what would be a better approach here....
2 similar functions with exactly same parameter list (one wrapper for another):
rte_ring_enqueue_elem_bulk_start() and rte_ring_enqueue_elem_bulk_start().
?
> > +{
> > + return __rte_ring_do_enqueue_start(r, n, RTE_RING_QUEUE_FIXED,
> > + free_space);
> > +}
> > +
>
<snip>
> >
> > > +
> > > +/**
> > > + * Start to enqueue several objects on the ring.
> > > + * Note that no actual objects are put in the queue by this
> > > +function,
> > > + * it just reserves for user such ability.
> > > + * User has to call appropriate enqueue_finish() to copy objects
> > > +into the
> > > + * queue and complete given enqueue operation.
> > > + *
> > > + * @param r
> > > + * A pointer to the ring structure.
> > > + * @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 that can be enqueued, either 0 or n
> > > + */
> > > +__rte_experimental
> > > +static __rte_always_inline unsigned int
> > > +rte_ring_enqueue_bulk_start(struct rte_ring *r, unsigned int n,
> > > + unsigned int *free_space)
> > If one wants to use _elem_ APIs for ring peek, a combination of legacy API
> (format) and a _elem_ API is required.
> > For ex:
> > rte_ring_enqueue_bulk_start
> > rte_ring_enqueue_elem_finish
> >
> > I understand why you have done this. I think this is getting somewhat too
> inconsistent.
> >
>
> Agree, there could be some confusion.
> Don't know what would be a better approach here....
> 2 similar functions with exactly same parameter list (one wrapper for
> another):
> rte_ring_enqueue_elem_bulk_start() and
> rte_ring_enqueue_elem_bulk_start().
> ?
We should go with 2 functions 'rte_ring_enqueue_bulk_start' and 'rte_ring_enqueue_bulk_elem_start'. There is a slight variation in the way obj_table is provided.
'rte_ring_enqueue_bulk_start' can be the wrapper.
>
> > > +{
> > > + return __rte_ring_do_enqueue_start(r, n, RTE_RING_QUEUE_FIXED,
> > > + free_space);
> > > +}
> > > +
> >
> > >
> > > > +
> > > > +/**
> > > > + * Start to enqueue several objects on the ring.
> > > > + * Note that no actual objects are put in the queue by this
> > > > +function,
> > > > + * it just reserves for user such ability.
> > > > + * User has to call appropriate enqueue_finish() to copy objects
> > > > +into the
> > > > + * queue and complete given enqueue operation.
> > > > + *
> > > > + * @param r
> > > > + * A pointer to the ring structure.
> > > > + * @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 that can be enqueued, either 0 or n
> > > > + */
> > > > +__rte_experimental
> > > > +static __rte_always_inline unsigned int
> > > > +rte_ring_enqueue_bulk_start(struct rte_ring *r, unsigned int n,
> > > > + unsigned int *free_space)
> > > If one wants to use _elem_ APIs for ring peek, a combination of legacy API
> > (format) and a _elem_ API is required.
> > > For ex:
> > > rte_ring_enqueue_bulk_start
> > > rte_ring_enqueue_elem_finish
> > >
> > > I understand why you have done this. I think this is getting somewhat too
> > inconsistent.
> > >
> >
> > Agree, there could be some confusion.
> > Don't know what would be a better approach here....
> > 2 similar functions with exactly same parameter list (one wrapper for
> > another):
> > rte_ring_enqueue_elem_bulk_start() and
> > rte_ring_enqueue_elem_bulk_start().
> > ?
> We should go with 2 functions 'rte_ring_enqueue_bulk_start' and 'rte_ring_enqueue_bulk_elem_start'.
> There is a slight variation in the way
> obj_table is provided.
> 'rte_ring_enqueue_bulk_start' can be the wrapper.
For enqueue_start() there is no need to have obj_table parameter.
That's why enqueue_start and enqueue_elem_start parameter list will be identical.
But sure, if that helps to avoid confusion - let's have 2 functions here.
>
> >
> > > > +{
> > > > + return __rte_ring_do_enqueue_start(r, n, RTE_RING_QUEUE_FIXED,
> > > > + free_space);
> > > > +}
> > > > +
> > >
@@ -22,6 +22,7 @@ SYMLINK-$(CONFIG_RTE_LIBRTE_RING)-include := rte_ring.h \
rte_ring_hts.h \
rte_ring_hts_elem.h \
rte_ring_hts_generic.h \
+ rte_ring_peek.h \
rte_ring_rts.h \
rte_ring_rts_elem.h \
rte_ring_rts_generic.h
@@ -9,6 +9,7 @@ headers = files('rte_ring.h',
'rte_ring_hts.h',
'rte_ring_hts_elem.h',
'rte_ring_hts_generic.h',
+ 'rte_ring_peek.h',
'rte_ring_rts.h',
'rte_ring_rts_elem.h',
'rte_ring_rts_generic.h')
@@ -10,6 +10,50 @@
#ifndef _RTE_RING_C11_MEM_H_
#define _RTE_RING_C11_MEM_H_
+/**
+ * @internal get current tail value.
+ * This function should be used only for single thread producer/consumer.
+ * Check that user didn't request to move tail above the head.
+ * In that situation:
+ * - return zero, that will cause abort any pending changes and
+ * return head to its previous position.
+ * - throw an assert in debug mode.
+ */
+static __rte_always_inline uint32_t
+__rte_ring_st_get_tail(struct rte_ring_headtail *ht, uint32_t *tail,
+ uint32_t num)
+{
+ uint32_t h, n, t;
+
+ h = ht->head;
+ t = ht->tail;
+ n = h - t;
+
+ RTE_ASSERT(n >= num);
+ num = (n >= num) ? num : 0;
+
+ *tail = h;
+ return num;
+}
+
+/**
+ * @internal set new values for head and tail.
+ * This function should be used only for single thread producer/consumer.
+ * Should be used only in conjunction with __rte_ring_st_get_tail.
+ */
+static __rte_always_inline void
+__rte_ring_st_set_head_tail(struct rte_ring_headtail *ht, uint32_t tail,
+ uint32_t num, uint32_t enqueue)
+{
+ uint32_t pos;
+
+ RTE_SET_USED(enqueue);
+
+ pos = tail + num;
+ ht->head = pos;
+ __atomic_store_n(&ht->tail, pos, __ATOMIC_RELEASE);
+}
+
static __rte_always_inline void
update_tail(struct rte_ring_headtail *ht, uint32_t old_val, uint32_t new_val,
uint32_t single, uint32_t enqueue)
@@ -1083,6 +1083,10 @@ rte_ring_dequeue_burst_elem(struct rte_ring *r, void *obj_table,
return 0;
}
+#ifdef ALLOW_EXPERIMENTAL_API
+#include <rte_ring_peek.h>
+#endif
+
#ifdef __cplusplus
}
#endif
@@ -10,6 +10,54 @@
#ifndef _RTE_RING_GENERIC_H_
#define _RTE_RING_GENERIC_H_
+/**
+ * @internal get current tail value.
+ * This function should be used only for single thread producer/consumer.
+ * Check that user didn't request to move tail above the head.
+ * In that situation:
+ * - return zero, that will cause abort any pending changes and
+ * return head to its previous position.
+ * - throw an assert in debug mode.
+ */
+static __rte_always_inline uint32_t
+__rte_ring_st_get_tail(struct rte_ring_headtail *ht, uint32_t *tail,
+ uint32_t num)
+{
+ uint32_t h, n, t;
+
+ h = ht->head;
+ t = ht->tail;
+ n = h - t;
+
+ RTE_ASSERT(n >= num);
+ num = (n >= num) ? num : 0;
+
+ *tail = h;
+ return num;
+}
+
+/**
+ * @internal set new values for head and tail.
+ * This function should be used only for single thread producer/consumer.
+ * Should be used only in conjunction with __rte_ring_st_get_tail.
+ */
+static __rte_always_inline void
+__rte_ring_st_set_head_tail(struct rte_ring_headtail *ht, uint32_t tail,
+ uint32_t num, uint32_t enqueue)
+{
+ uint32_t pos;
+
+ pos = tail + num;
+
+ if (enqueue)
+ rte_smp_wmb();
+ else
+ rte_smp_rmb();
+
+ ht->head = pos;
+ ht->tail = pos;
+}
+
static __rte_always_inline void
update_tail(struct rte_ring_headtail *ht, uint32_t old_val, uint32_t new_val,
uint32_t single, uint32_t enqueue)
@@ -18,9 +18,38 @@
* For more information please refer to <rte_ring_hts.h>.
*/
+/**
+ * @internal get current tail value.
+ * Check that user didn't request to move tail above the head.
+ * In that situation:
+ * - return zero, that will cause abort any pending changes and
+ * return head to its previous position.
+ * - throw an assert in debug mode.
+ */
+static __rte_always_inline uint32_t
+__rte_ring_hts_get_tail(struct rte_ring_hts_headtail *ht, uint32_t *tail,
+ uint32_t num)
+{
+ uint32_t n;
+ union rte_ring_ht_pos p;
+
+ p.raw = rte_atomic64_read((rte_atomic64_t *)(uintptr_t)&ht->ht.raw);
+ n = p.pos.head - p.pos.tail;
+
+ RTE_ASSERT(n >= num);
+ num = (n >= num) ? num : 0;
+
+ *tail = p.pos.tail;
+ return num;
+}
+
+/**
+ * @internal set new values for head and tail as one atomic 64 bit operation.
+ * Should be used only in conjunction with __rte_ring_hts_get_tail.
+ */
static __rte_always_inline void
-__rte_ring_hts_update_tail(struct rte_ring_hts_headtail *ht, uint32_t num,
- uint32_t enqueue)
+__rte_ring_hts_set_head_tail(struct rte_ring_hts_headtail *ht, uint32_t tail,
+ uint32_t num, uint32_t enqueue)
{
union rte_ring_ht_pos p;
@@ -29,14 +58,22 @@ __rte_ring_hts_update_tail(struct rte_ring_hts_headtail *ht, uint32_t num,
else
rte_smp_rmb();
- p.raw = rte_atomic64_read((rte_atomic64_t *)(uintptr_t)&ht->ht.raw);
-
- p.pos.head = p.pos.tail + num;
+ p.pos.head = tail + num;
p.pos.tail = p.pos.head;
rte_atomic64_set((rte_atomic64_t *)(uintptr_t)&ht->ht.raw, p.raw);
}
+static __rte_always_inline void
+__rte_ring_hts_update_tail(struct rte_ring_hts_headtail *ht, uint32_t num,
+ uint32_t enqueue)
+{
+ uint32_t tail;
+
+ num = __rte_ring_hts_get_tail(ht, &tail, num);
+ __rte_ring_hts_set_head_tail(ht, tail, num, enqueue);
+}
+
/**
* @internal waits till tail will become equal to head.
* Means no writer/reader is active for that ring.
new file mode 100644
@@ -0,0 +1,379 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ *
+ * Copyright (c) 2010-2017 Intel Corporation
+ * Copyright (c) 2007-2009 Kip Macy kmacy@freebsd.org
+ * All rights reserved.
+ * Derived from FreeBSD's bufring.h
+ * Used as BSD-3 Licensed with permission from Kip Macy.
+ */
+
+#ifndef _RTE_RING_PEEK_H_
+#define _RTE_RING_PEEK_H_
+
+/**
+ * @file
+ * @b EXPERIMENTAL: this API may change without prior notice
+ * It is not recommended to include this file directly.
+ * Please include <rte_ring_elem.h> instead.
+ *
+ * Ring Peek AP
+ * Introduction of rte_ring with serialized producer/consumer (HTS sync mode)
+ * makes possible to split public enqueue/dequeue API into two phases:
+ * - enqueue/dequeue start
+ * - enqueue/dequeue finish
+ * That allows user to inspect objects in the ring without removing them
+ * from it (aka MT safe peek).
+ * Note that right now this new API is avaialble only for two sync modes:
+ * 1) Single Producer/Single Consumer (RTE_RING_SYNC_ST)
+ * 2) Serialized Producer/Serialized Consumer (RTE_RING_SYNC_MT_HTS).
+ * It is a user responsibility to create/init ring with appropriate sync
+ * modes selected.
+ * As an example:
+ * // read 1 elem from the ring:
+ * n = rte_ring_hts_dequeue_bulk_start(ring, &obj, 1, NULL);
+ * if (n != 0) {
+ * //examine object
+ * if (object_examine(obj) == KEEP)
+ * //decided to keep it in the ring.
+ * rte_ring_hts_dequeue_finish(ring, 0);
+ * else
+ * //decided to remove it from the ring.
+ * rte_ring_hts_dequeue_finish(ring, n);
+ * }
+ * Note that between _start_ and _finish_ the ring is sort of locked -
+ * none other thread can proceed with enqueue(/dequeue) operation till
+ * _finish_ will complete.
+ */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @internal This function moves prod head value.
+ */
+static __rte_always_inline unsigned int
+__rte_ring_do_enqueue_start(struct rte_ring *r, uint32_t n,
+ enum rte_ring_queue_behavior behavior, uint32_t *free_space)
+{
+ uint32_t free, head, next;
+
+ switch (r->prod.sync_type) {
+ case RTE_RING_SYNC_ST:
+ n = __rte_ring_move_prod_head(r, RTE_RING_SYNC_ST, n,
+ behavior, &head, &next, &free);
+ break;
+ case RTE_RING_SYNC_MT_HTS:
+ n = __rte_ring_hts_move_prod_head(r, n, behavior,
+ &head, &free);
+ break;
+ default:
+ /* unsupported mode, shouldn't be here */
+ RTE_ASSERT(0);
+ n = 0;
+ }
+
+ if (free_space != NULL)
+ *free_space = free - n;
+ return n;
+}
+
+/**
+ * Start to enqueue several objects on the ring.
+ * Note that no actual objects are put in the queue by this function,
+ * it just reserves for user such ability.
+ * User has to call appropriate enqueue_finish() to copy objects into the
+ * queue and complete given enqueue operation.
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @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 that can be enqueued, either 0 or n
+ */
+__rte_experimental
+static __rte_always_inline unsigned int
+rte_ring_enqueue_bulk_start(struct rte_ring *r, unsigned int n,
+ unsigned int *free_space)
+{
+ return __rte_ring_do_enqueue_start(r, n, RTE_RING_QUEUE_FIXED,
+ free_space);
+}
+
+/**
+ * Start to enqueue several objects on the ring.
+ * Note that no actual objects are put in the queue by this function,
+ * it just reserves for user such ability.
+ * User has to call appropriate enqueue_finish() to copy objects into the
+ * queue and complete given enqueue operation.
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @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
+ * Actual number of objects that can be enqueued.
+ */
+__rte_experimental
+static __rte_always_inline unsigned int
+rte_ring_enqueue_burst_start(struct rte_ring *r, unsigned int n,
+ unsigned int *free_space)
+{
+ return __rte_ring_do_enqueue_start(r, n, RTE_RING_QUEUE_VARIABLE,
+ free_space);
+}
+
+/**
+ * Complete to enqueue several objects on the ring.
+ * Note that number of objects to enqueue should not exceed previous
+ * enqueue_start return value.
+ *
+ * @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 to the ring from the obj_table.
+ */
+__rte_experimental
+static __rte_always_inline void
+rte_ring_enqueue_elem_finish(struct rte_ring *r, void * const *obj_table,
+ unsigned int esize, unsigned int n)
+{
+ uint32_t tail;
+
+ switch (r->prod.sync_type) {
+ case RTE_RING_SYNC_ST:
+ n = __rte_ring_st_get_tail(&r->prod, &tail, n);
+ if (n != 0)
+ __rte_ring_enqueue_elems(r, tail, obj_table, esize, n);
+ __rte_ring_st_set_head_tail(&r->prod, tail, n, 1);
+ break;
+ case RTE_RING_SYNC_MT_HTS:
+ n = __rte_ring_hts_get_tail(&r->hts_prod, &tail, n);
+ if (n != 0)
+ __rte_ring_enqueue_elems(r, tail, obj_table, esize, n);
+ __rte_ring_hts_set_head_tail(&r->hts_prod, tail, n, 1);
+ break;
+ default:
+ /* unsupported mode, shouldn't be here */
+ RTE_ASSERT(0);
+ }
+}
+
+/**
+ * Complete to enqueue several objects on the ring.
+ * Note that number of objects to enqueue should not exceed previous
+ * enqueue_start return value.
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param obj_table
+ * A pointer to a table of objects.
+ * @param n
+ * The number of objects to add to the ring from the obj_table.
+ */
+__rte_experimental
+static __rte_always_inline void
+rte_ring_enqueue_finish(struct rte_ring *r, void * const *obj_table,
+ unsigned int n)
+{
+ rte_ring_enqueue_elem_finish(r, obj_table, sizeof(uintptr_t), n);
+}
+
+/**
+ * @internal This function moves cons head value and copies up to *n*
+ * objects from the ring to the user provided obj_table.
+ */
+static __rte_always_inline unsigned int
+__rte_ring_do_dequeue_start(struct rte_ring *r, void **obj_table,
+ uint32_t esize, uint32_t n, enum rte_ring_queue_behavior behavior,
+ uint32_t *available)
+{
+ uint32_t avail, head, next;
+
+ switch (r->cons.sync_type) {
+ case RTE_RING_SYNC_ST:
+ n = __rte_ring_move_cons_head(r, RTE_RING_SYNC_ST, n,
+ behavior, &head, &next, &avail);
+ break;
+ case RTE_RING_SYNC_MT_HTS:
+ n = __rte_ring_hts_move_cons_head(r, n, behavior,
+ &head, &avail);
+ break;
+ default:
+ /* unsupported mode, shouldn't be here */
+ RTE_ASSERT(0);
+ n = 0;
+ }
+
+ if (n != 0)
+ __rte_ring_dequeue_elems(r, head, obj_table, esize, n);
+
+ if (available != NULL)
+ *available = avail - n;
+ return n;
+}
+
+/**
+ * Start to dequeue several objects from the ring.
+ * Note that user has to call appropriate dequeue_finish()
+ * to complete given dequeue operation and actually remove objects the ring.
+ *
+ * @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 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.
+ */
+__rte_experimental
+static __rte_always_inline unsigned int
+rte_ring_dequeue_bulk_elem_start(struct rte_ring *r, void **obj_table,
+ unsigned int esize, unsigned int n, unsigned int *available)
+{
+ return __rte_ring_do_dequeue_start(r, obj_table, esize, n,
+ RTE_RING_QUEUE_FIXED, available);
+}
+
+/**
+ * Start to dequeue several objects from the ring.
+ * Note that user has to call appropriate dequeue_finish()
+ * to complete given dequeue operation and actually remove objects the ring.
+ *
+ * @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 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
+ * Actual number of objects dequeued.
+ */
+__rte_experimental
+static __rte_always_inline unsigned int
+rte_ring_dequeue_bulk_start(struct rte_ring *r, void **obj_table,
+ unsigned int n, unsigned int *available)
+{
+ return rte_ring_dequeue_bulk_elem_start(r, obj_table, sizeof(uintptr_t),
+ n, available);
+}
+
+/**
+ * Start to dequeue several objects from the ring.
+ * Note that user has to call appropriate dequeue_finish()
+ * to complete given dequeue operation and actually remove objects the ring.
+ *
+ * @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 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 actual number of objects dequeued.
+ */
+__rte_experimental
+static __rte_always_inline unsigned int
+rte_ring_dequeue_burst_elem_start(struct rte_ring *r, void **obj_table,
+ unsigned int esize, unsigned int n, unsigned int *available)
+{
+ return __rte_ring_do_dequeue_start(r, obj_table, esize, n,
+ RTE_RING_QUEUE_VARIABLE, available);
+}
+
+/**
+ * Start to dequeue several objects from the ring.
+ * Note that user has to call appropriate dequeue_finish()
+ * to complete given dequeue operation and actually remove objects the ring.
+ *
+ * @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 actual number of objects dequeued.
+ */
+__rte_experimental
+static __rte_always_inline unsigned int
+rte_ring_dequeue_burst_start(struct rte_ring *r, void **obj_table,
+ unsigned int n, unsigned int *available)
+{
+ return rte_ring_dequeue_burst_elem_start(r, obj_table,
+ sizeof(uintptr_t), n, available);
+}
+
+/**
+ * Complete to dequeue several objects from the ring.
+ * Note that number of objects to dequeue should not exceed previous
+ * dequeue_start return value.
+ *
+ * @param r
+ * A pointer to the ring structure.
+ * @param n
+ * The number of objects to add to the ring from the obj_table.
+ */
+__rte_experimental
+static __rte_always_inline void
+rte_ring_dequeue_finish(struct rte_ring *r, unsigned int n)
+{
+ uint32_t tail;
+
+ switch (r->cons.sync_type) {
+ case RTE_RING_SYNC_ST:
+ n = __rte_ring_st_get_tail(&r->cons, &tail, n);
+ __rte_ring_st_set_head_tail(&r->cons, tail, n, 0);
+ break;
+ case RTE_RING_SYNC_MT_HTS:
+ __rte_ring_hts_update_tail(&r->hts_cons, n, 0);
+ break;
+ default:
+ /* unsupported mode, shouldn't be here */
+ RTE_ASSERT(0);
+ }
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _RTE_RING_PEEK_H_ */