src/gallium/drivers/vc4/vc4_fence.c

   1 /*
   2  * Copyright © 2014 Broadcom
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21  * IN THE SOFTWARE.
  22  */
  23
  24 /** @file vc4_fence.c
  25  *
  26  * Seqno-based fence management.
  27  *
  28  * We have two mechanisms for waiting in our kernel API: You can wait on a BO
  29  * to have all rendering to from any process to be completed, or wait on a
  30  * seqno for that particular seqno to be passed.  The fence API we're
  31  * implementing is based on waiting for all rendering in the context to have
  32  * completed (with no reference to what other processes might be doing with
  33  * the same BOs), so we can just use the seqno of the last rendering we'd
  34  * fired off as our fence marker.
  35  */
  36
  37 #include <libsync.h>
  38 #include <fcntl.h>
  39
  40 #include "util/u_inlines.h"
  41
  42 #include "vc4_screen.h"
  43 #include "vc4_context.h"
  44 #include "vc4_bufmgr.h"
  45
  46 struct vc4_fence {
  47         struct pipe_reference reference;
  48         uint64_t seqno;
  49         int fd;
  50 };
  51
  52 static inline struct vc4_fence *
  53 vc4_fence(struct pipe_fence_handle *pfence)
  54 {
  55         return (struct vc4_fence *)pfence;
  56 }
  57
  58 static void
  59 vc4_fence_reference(struct pipe_screen *pscreen,
  60                     struct pipe_fence_handle **pp,
  61                     struct pipe_fence_handle *pf)
  62 {
  63         struct vc4_fence **p = (struct vc4_fence **)pp;
  64         struct vc4_fence *f = vc4_fence(pf);
  65         struct vc4_fence *old = *p;
  66
  67         if (pipe_reference(&(*p)->reference, &f->reference)) {
  68                 if (old->fd >= 0)
  69                         close(old->fd);
  70                 free(old);
  71         }
  72         *p = f;
  73 }
  74
  75 static bool
  76 vc4_fence_finish(struct pipe_screen *pscreen,
  77                  struct pipe_context *ctx,
  78                  struct pipe_fence_handle *pf,
  79                  uint64_t timeout_ns)
  80 {
  81         struct vc4_screen *screen = vc4_screen(pscreen);
  82         struct vc4_fence *f = vc4_fence(pf);
  83
  84         if (f->fd >= 0)
  85                 return sync_wait(f->fd, timeout_ns / 1000000) == 0;
  86
  87         return vc4_wait_seqno(screen, f->seqno, timeout_ns, "fence wait");
  88 }
  89
  90 struct vc4_fence *
  91 vc4_fence_create(struct vc4_screen *screen, uint64_t seqno, int fd)
  92 {
  93         struct vc4_fence *f = calloc(1, sizeof(*f));
  94
  95         if (!f)
  96                 return NULL;
  97
  98         pipe_reference_init(&f->reference, 1);
  99         f->seqno = seqno;
 100         f->fd = fd;
 101
 102         return f;
 103 }
 104
 105 static void
 106 vc4_fence_create_fd(struct pipe_context *pctx, struct pipe_fence_handle **pf,
 107                     int fd, enum pipe_fd_type type)
 108 {
 109         struct vc4_context *vc4 = vc4_context(pctx);
 110         struct vc4_fence **fence = (struct vc4_fence **)pf;
 111
 112         assert(type == PIPE_FD_TYPE_NATIVE_SYNC);
 113         *fence = vc4_fence_create(vc4->screen, vc4->last_emit_seqno,
 114                                   fcntl(fd, F_DUPFD_CLOEXEC, 3));
 115 }
 116
 117 static void
 118 vc4_fence_server_sync(struct pipe_context *pctx,
 119                       struct pipe_fence_handle *pfence)
 120 {
 121         struct vc4_context *vc4 = vc4_context(pctx);
 122         struct vc4_fence *fence = vc4_fence(pfence);
 123
 124         if (fence->fd >= 0)
 125                 sync_accumulate("vc4", &vc4->in_fence_fd, fence->fd);
 126 }
 127
 128 static int
 129 vc4_fence_get_fd(struct pipe_screen *screen, struct pipe_fence_handle *pfence)
 130 {
 131         struct vc4_fence *fence = vc4_fence(pfence);
 132
 133         return fcntl(fence->fd, F_DUPFD_CLOEXEC, 3);
 134 }
 135
 136 int
 137 vc4_fence_context_init(struct vc4_context *vc4)
 138 {
 139         vc4->base.create_fence_fd = vc4_fence_create_fd;
 140         vc4->base.fence_server_sync = vc4_fence_server_sync;
 141         vc4->in_fence_fd = -1;
 142
 143         /* Since we initialize the in_fence_fd to -1 (no wait necessary),
 144          * we also need to initialize our in_syncobj as signaled.
 145          */
 146         if (vc4->screen->has_syncobj) {
 147                 return drmSyncobjCreate(vc4->fd, DRM_SYNCOBJ_CREATE_SIGNALED,
 148                                         &vc4->in_syncobj);
 149         } else {
 150                 return 0;
 151         }
 152 }
 153
 154 void
 155 vc4_fence_screen_init(struct vc4_screen *screen)
 156 {
 157         screen->base.fence_reference = vc4_fence_reference;
 158         screen->base.fence_finish = vc4_fence_finish;
 159         screen->base.fence_get_fd = vc4_fence_get_fd;
 160 }