From aed75f3d1d6ba74e05f45471f0548f40a060364f Mon Sep 17 00:00:00 2001 From: Damjan Marion Date: Fri, 28 Dec 2018 15:46:10 +0100 Subject: vppinfra: add simple ring implementation Change-Id: I188e2dfd187d7b2ab7e0fbb11461f3db052f3224 Signed-off-by: Damjan Marion --- src/vppinfra/ring.h | 134 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 134 insertions(+) create mode 100644 src/vppinfra/ring.h (limited to 'src') diff --git a/src/vppinfra/ring.h b/src/vppinfra/ring.h new file mode 100644 index 00000000000..be61dc44978 --- /dev/null +++ b/src/vppinfra/ring.h @@ -0,0 +1,134 @@ +/* + * Copyright (c) 2018 Cisco and/or its affiliates. + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#ifndef included_ring_h +#define included_ring_h + +#include +#include +#include +#include + +typedef struct +{ + u32 next, n_enq; +} clib_ring_header_t; + +always_inline clib_ring_header_t * +clib_ring_header (void *v) +{ + return vec_aligned_header (v, sizeof (clib_ring_header_t), sizeof (void *)); +} + +always_inline void +clib_ring_new_inline (void **p, u32 elt_bytes, u32 size, u32 align) +{ + void *v; + clib_ring_header_t *h; + + v = _vec_resize ((void *) 0, + /* length increment */ size, + /* data bytes */ elt_bytes * size, + /* header bytes */ sizeof (h[0]), + /* data align */ align); + + h = clib_ring_header (v); + h->next = 0; + h->n_enq = 0; + p[0] = v; +} + +#define clib_ring_new_aligned(ring, size, align) \ +{ clib_ring_new_inline ((void **)&(ring), sizeof(ring[0]), size, align); } + +#define clib_ring_new(ring, size) \ +{ clib_ring_new_inline ((void **)&(ring), sizeof(ring[0]), size, 0);} + +#define clib_ring_free(f) vec_free_h((f), sizeof(clib_ring_header_t)) + +always_inline u32 +clib_ring_n_enq (void *v) +{ + clib_ring_header_t *h = clib_ring_header (v); + return h->n_enq; +} + +always_inline void * +clib_ring_get_last_inline (void *v, u32 elt_bytes, int enqueue) +{ + clib_ring_header_t *h = clib_ring_header (v); + u32 slot; + + if (enqueue) + { + if (h->n_enq == _vec_len (v)) + return 0; + slot = h->next; + h->n_enq++; + h->next++; + if (h->next == _vec_len (v)) + h->next = 0; + } + else + { + if (h->n_enq == 0) + return 0; + slot = h->next == 0 ? _vec_len (v) - 1 : h->next - 1; + } + + return (void *) ((u8 *) v + elt_bytes * slot); +} + +#define clib_ring_enq(ring) \ +clib_ring_get_last_inline (ring, sizeof(ring[0]), 1) + +#define clib_ring_get_last(ring) \ +clib_ring_get_last_inline (ring, sizeof(ring[0]), 0) + +always_inline void * +clib_ring_get_first_inline (void *v, u32 elt_bytes, int dequeue) +{ + clib_ring_header_t *h = clib_ring_header (v); + u32 slot; + + if (h->n_enq == 0) + return 0; + + if (h->n_enq > h->next) + slot = _vec_len (v) + h->next - h->n_enq; + else + slot = h->next - h->n_enq; + + if (dequeue) + h->n_enq--; + + return (void *) ((u8 *) v + elt_bytes * slot); +} + +#define clib_ring_deq(ring) \ +clib_ring_get_first_inline (ring, sizeof(ring[0]), 1) + +#define clib_ring_get_first(ring) \ +clib_ring_get_first_inline (ring, sizeof(ring[0]), 0) + +#endif /* included_ring_h */ + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ -- cgit 1.2.3-korg