| /* |
| * Copyright (c) 2013-2015, Intel Corporation |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are met: |
| * |
| * * Redistributions of source code must retain the above copyright notice, |
| * this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above copyright notice, |
| * this list of conditions and the following disclaimer in the documentation |
| * and/or other materials provided with the distribution. |
| * * Neither the name of Intel Corporation nor the names of its contributors |
| * may be used to endorse or promote products derived from this software |
| * without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
| * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| * POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "pt_event_queue.h" |
| |
| #include <string.h> |
| |
| |
| static inline uint8_t pt_evq_inc(uint8_t idx) |
| { |
| idx += 1; |
| idx %= evq_max; |
| |
| return idx; |
| } |
| |
| static struct pt_event *pt_event_init(struct pt_event *event) |
| { |
| if (event) |
| memset(event, 0, sizeof(*event)); |
| |
| return event; |
| } |
| |
| void pt_evq_init(struct pt_event_queue *evq) |
| { |
| if (!evq) |
| return; |
| |
| memset(evq, 0, sizeof(*evq)); |
| } |
| |
| struct pt_event *pt_evq_standalone(struct pt_event_queue *evq) |
| { |
| if (!evq) |
| return NULL; |
| |
| return pt_event_init(&evq->standalone); |
| } |
| |
| struct pt_event *pt_evq_enqueue(struct pt_event_queue *evq, |
| enum pt_event_binding evb) |
| { |
| uint8_t begin, end, gap, idx; |
| |
| if (!evq) |
| return NULL; |
| |
| if (evb_max <= evb) |
| return NULL; |
| |
| begin = evq->begin[evb]; |
| idx = evq->end[evb]; |
| |
| if (evq_max <= begin) |
| return NULL; |
| |
| if (evq_max <= idx) |
| return NULL; |
| |
| end = pt_evq_inc(idx); |
| gap = pt_evq_inc(end); |
| |
| /* Leave a gap so we don't overwrite the last dequeued event. */ |
| if (begin == gap) |
| return NULL; |
| |
| evq->end[evb] = end; |
| |
| return pt_event_init(&evq->queue[evb][idx]); |
| } |
| |
| struct pt_event *pt_evq_dequeue(struct pt_event_queue *evq, |
| enum pt_event_binding evb) |
| { |
| uint8_t begin, end; |
| |
| if (!evq) |
| return NULL; |
| |
| if (evb_max <= evb) |
| return NULL; |
| |
| begin = evq->begin[evb]; |
| end = evq->end[evb]; |
| |
| if (evq_max <= begin) |
| return NULL; |
| |
| if (evq_max <= end) |
| return NULL; |
| |
| if (begin == end) |
| return NULL; |
| |
| evq->begin[evb] = pt_evq_inc(begin); |
| |
| return &evq->queue[evb][begin]; |
| } |
| |
| int pt_evq_clear(struct pt_event_queue *evq, enum pt_event_binding evb) |
| { |
| if (!evq) |
| return -pte_internal; |
| |
| if (evb_max <= evb) |
| return -pte_internal; |
| |
| evq->begin[evb] = 0; |
| evq->end[evb] = 0; |
| |
| return 0; |
| } |
| |
| int pt_evq_empty(const struct pt_event_queue *evq, enum pt_event_binding evb) |
| { |
| uint8_t begin, end; |
| |
| if (!evq) |
| return -pte_internal; |
| |
| if (evb_max <= evb) |
| return -pte_internal; |
| |
| begin = evq->begin[evb]; |
| end = evq->end[evb]; |
| |
| if (evq_max <= begin) |
| return -pte_internal; |
| |
| if (evq_max <= end) |
| return -pte_internal; |
| |
| return begin == end; |
| } |
| |
| int pt_evq_pending(const struct pt_event_queue *evq, enum pt_event_binding evb) |
| { |
| int errcode; |
| |
| errcode = pt_evq_empty(evq, evb); |
| if (errcode < 0) |
| return errcode; |
| |
| return !errcode; |
| } |
| |
| struct pt_event *pt_evq_find(struct pt_event_queue *evq, |
| enum pt_event_binding evb, |
| enum pt_event_type evt) |
| { |
| uint8_t begin, end; |
| |
| if (!evq) |
| return NULL; |
| |
| if (evb_max <= evb) |
| return NULL; |
| |
| begin = evq->begin[evb]; |
| end = evq->end[evb]; |
| |
| if (evq_max <= begin) |
| return NULL; |
| |
| if (evq_max <= end) |
| return NULL; |
| |
| for (; begin != end; begin = pt_evq_inc(begin)) { |
| struct pt_event *ev; |
| |
| ev = &evq->queue[evb][begin]; |
| if (ev->type == evt) |
| return ev; |
| } |
| |
| return NULL; |
| } |