1/**************************************************************************
2 *
3 * Copyright 2009 VMware, Inc.
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
21 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27
28
29#include "pipe/p_screen.h"
30#include "util/u_memory.h"
31#include "lp_debug.h"
32#include "lp_fence.h"
33
34
35#include "util/timespec.h"
36
37/**
38 * Create a new fence object.
39 *
40 * The rank will be the number of bins in the scene.  Whenever a rendering
41 * thread hits a fence command, it'll increment the fence counter.  When
42 * the counter == the rank, the fence is finished.
43 *
44 * \param rank  the expected finished value of the fence counter.
45 */
46struct lp_fence *
47lp_fence_create(unsigned rank)
48{
49   static unsigned fence_id = 0;
50   struct lp_fence *fence = CALLOC_STRUCT(lp_fence);
51
52   if (!fence)
53      return NULL;
54
55   pipe_reference_init(&fence->reference, 1);
56
57   (void) mtx_init(&fence->mutex, mtx_plain);
58   cnd_init(&fence->signalled);
59
60   fence->id = p_atomic_inc_return(&fence_id) - 1;
61   fence->rank = rank;
62
63   if (LP_DEBUG & DEBUG_FENCE)
64      debug_printf("%s %d\n", __FUNCTION__, fence->id);
65
66   return fence;
67}
68
69
70/** Destroy a fence.  Called when refcount hits zero. */
71void
72lp_fence_destroy(struct lp_fence *fence)
73{
74   if (LP_DEBUG & DEBUG_FENCE)
75      debug_printf("%s %d\n", __FUNCTION__, fence->id);
76
77   mtx_destroy(&fence->mutex);
78   cnd_destroy(&fence->signalled);
79   FREE(fence);
80}
81
82
83/**
84 * Called by the rendering threads to increment the fence counter.
85 * When the counter == the rank, the fence is finished.
86 */
87void
88lp_fence_signal(struct lp_fence *fence)
89{
90   if (LP_DEBUG & DEBUG_FENCE)
91      debug_printf("%s %d\n", __FUNCTION__, fence->id);
92
93   mtx_lock(&fence->mutex);
94
95   fence->count++;
96   assert(fence->count <= fence->rank);
97
98   if (LP_DEBUG & DEBUG_FENCE)
99      debug_printf("%s count=%u rank=%u\n", __FUNCTION__,
100                   fence->count, fence->rank);
101
102   /* Wakeup all threads waiting on the mutex:
103    */
104   cnd_broadcast(&fence->signalled);
105
106   mtx_unlock(&fence->mutex);
107}
108
109boolean
110lp_fence_signalled(struct lp_fence *f)
111{
112   return f->count == f->rank;
113}
114
115void
116lp_fence_wait(struct lp_fence *f)
117{
118   if (LP_DEBUG & DEBUG_FENCE)
119      debug_printf("%s %d\n", __FUNCTION__, f->id);
120
121   mtx_lock(&f->mutex);
122   assert(f->issued);
123   while (f->count < f->rank) {
124      cnd_wait(&f->signalled, &f->mutex);
125   }
126   mtx_unlock(&f->mutex);
127}
128
129
130boolean
131lp_fence_timedwait(struct lp_fence *f, uint64_t timeout)
132{
133   struct timespec ts, abs_ts;
134   int ret;
135
136   timespec_get(&ts, TIME_UTC);
137
138   bool ts_overflow = timespec_add_nsec(&abs_ts, &ts, timeout);
139
140   if (LP_DEBUG & DEBUG_FENCE)
141      debug_printf("%s %d\n", __FUNCTION__, f->id);
142
143   mtx_lock(&f->mutex);
144   assert(f->issued);
145   while (f->count < f->rank) {
146      if (ts_overflow)
147         ret = cnd_wait(&f->signalled, &f->mutex);
148      else
149         ret = cnd_timedwait(&f->signalled, &f->mutex, &abs_ts);
150      if (ret != thrd_success)
151         break;
152   }
153   const boolean result = (f->count >= f->rank);
154   mtx_unlock(&f->mutex);
155   return result;
156}
157