src/util/u_queue.h

   1 /*
   2  * Copyright © 2016 Advanced Micro Devices, Inc.
   3  * All Rights Reserved.
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining
   6  * a copy of this software and associated documentation files (the
   7  * "Software"), to deal in the Software without restriction, including
   8  * without limitation the rights to use, copy, modify, merge, publish,
   9  * distribute, sub license, and/or sell copies of the Software, and to
  10  * permit persons to whom the Software is furnished to do so, subject to
  11  * the following conditions:
  12  *
  13  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  14  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
  15  * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  16  * NON-INFRINGEMENT. IN NO EVENT SHALL THE COPYRIGHT HOLDERS, AUTHORS
  17  * AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  18  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  20  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  21  *
  22  * The above copyright notice and this permission notice (including the
  23  * next paragraph) shall be included in all copies or substantial portions
  24  * of the Software.
  25  */
  26
  27 /* Job queue with execution in a separate thread.
  28  *
  29  * Jobs can be added from any thread. After that, the wait call can be used
  30  * to wait for completion of the job.
  31  */
  32
  33 #ifndef U_QUEUE_H
  34 #define U_QUEUE_H
  35
  36 #include <string.h>
  37
  38 #include "util/futex.h"
  39 #include "util/list.h"
  40 #include "util/macros.h"
  41 #include "util/os_time.h"
  42 #include "util/u_atomic.h"
  43 #include "util/u_thread.h"
  44
  45 #ifdef __cplusplus
  46 extern "C" {
  47 #endif
  48
  49 #define UTIL_QUEUE_INIT_USE_MINIMUM_PRIORITY      (1 << 0)
  50 #define UTIL_QUEUE_INIT_RESIZE_IF_FULL            (1 << 1)
  51
  52 #if defined(__GNUC__) && defined(HAVE_LINUX_FUTEX_H)
  53 #define UTIL_QUEUE_FENCE_FUTEX
  54 #else
  55 #define UTIL_QUEUE_FENCE_STANDARD
  56 #endif
  57
  58 #ifdef UTIL_QUEUE_FENCE_FUTEX
  59 /* Job completion fence.
  60  * Put this into your job structure.
  61  */
  62 struct util_queue_fence {
  63    /* The fence can be in one of three states:
  64     *  0 - signaled
  65     *  1 - unsignaled
  66     *  2 - unsignaled, may have waiters
  67     */
  68    uint32_t val;
  69 };
  70
  71 static inline void
  72 util_queue_fence_init(struct util_queue_fence *fence)
  73 {
  74    fence->val = 0;
  75 }
  76
  77 static inline void
  78 util_queue_fence_destroy(struct util_queue_fence *fence)
  79 {
  80    assert(fence->val == 0);
  81    /* no-op */
  82 }
  83
  84 static inline void
  85 util_queue_fence_signal(struct util_queue_fence *fence)
  86 {
  87    uint32_t val = p_atomic_xchg(&fence->val, 0);
  88
  89    assert(val != 0);
  90
  91    if (val == 2)
  92       futex_wake(&fence->val, INT_MAX);
  93 }
  94
  95 /**
  96  * Move \p fence back into unsignalled state.
  97  *
  98  * \warning The caller must ensure that no other thread may currently be
  99  *          waiting (or about to wait) on the fence.
 100  */
 101 static inline void
 102 util_queue_fence_reset(struct util_queue_fence *fence)
 103 {
 104 #ifdef NDEBUG
 105    fence->val = 1;
 106 #else
 107    uint32_t v = p_atomic_xchg(&fence->val, 1);
 108    assert(v == 0);
 109 #endif
 110 }
 111
 112 static inline bool
 113 util_queue_fence_is_signalled(struct util_queue_fence *fence)
 114 {
 115    return fence->val == 0;
 116 }
 117 #endif
 118
 119 #ifdef UTIL_QUEUE_FENCE_STANDARD
 120 /* Job completion fence.
 121  * Put this into your job structure.
 122  */
 123 struct util_queue_fence {
 124    mtx_t mutex;
 125    cnd_t cond;
 126    int signalled;
 127 };
 128
 129 void util_queue_fence_init(struct util_queue_fence *fence);
 130 void util_queue_fence_destroy(struct util_queue_fence *fence);
 131 void util_queue_fence_signal(struct util_queue_fence *fence);
 132
 133 /**
 134  * Move \p fence back into unsignalled state.
 135  *
 136  * \warning The caller must ensure that no other thread may currently be
 137  *          waiting (or about to wait) on the fence.
 138  */
 139 static inline void
 140 util_queue_fence_reset(struct util_queue_fence *fence)
 141 {
 142    assert(fence->signalled);
 143    fence->signalled = 0;
 144 }
 145
 146 static inline bool
 147 util_queue_fence_is_signalled(struct util_queue_fence *fence)
 148 {
 149    return fence->signalled != 0;
 150 }
 151 #endif
 152
 153 void
 154 _util_queue_fence_wait(struct util_queue_fence *fence);
 155
 156 static inline void
 157 util_queue_fence_wait(struct util_queue_fence *fence)
 158 {
 159    if (unlikely(!util_queue_fence_is_signalled(fence)))
 160       _util_queue_fence_wait(fence);
 161 }
 162
 163 bool
 164 _util_queue_fence_wait_timeout(struct util_queue_fence *fence,
 165                                int64_t abs_timeout);
 166
 167 /**
 168  * Wait for the fence to be signaled with a timeout.
 169  *
 170  * \param fence the fence
 171  * \param abs_timeout the absolute timeout in nanoseconds, relative to the
 172  *                    clock provided by os_time_get_nano.
 173  *
 174  * \return true if the fence was signaled, false if the timeout occurred.
 175  */
 176 static inline bool
 177 util_queue_fence_wait_timeout(struct util_queue_fence *fence,
 178                               int64_t abs_timeout)
 179 {
 180    if (util_queue_fence_is_signalled(fence))
 181       return true;
 182
 183    if (abs_timeout == (int64_t)OS_TIMEOUT_INFINITE) {
 184       _util_queue_fence_wait(fence);
 185       return true;
 186    }
 187
 188    return _util_queue_fence_wait_timeout(fence, abs_timeout);
 189 }
 190
 191 typedef void (*util_queue_execute_func)(void *job, int thread_index);
 192
 193 struct util_queue_job {
 194    void *job;
 195    struct util_queue_fence *fence;
 196    util_queue_execute_func execute;
 197    util_queue_execute_func cleanup;
 198 };
 199
 200 /* Put this into your context. */
 201 struct util_queue {
 202    const char *name;
 203    mtx_t finish_lock; /* only for util_queue_finish */
 204    mtx_t lock;
 205    cnd_t has_queued_cond;
 206    cnd_t has_space_cond;
 207    thrd_t *threads;
 208    unsigned flags;
 209    int num_queued;
 210    unsigned num_threads;
 211    int kill_threads;
 212    int max_jobs;
 213    int write_idx, read_idx; /* ring buffer pointers */
 214    struct util_queue_job *jobs;
 215
 216    /* for cleanup at exit(), protected by exit_mutex */
 217    struct list_head head;
 218 };
 219
 220 bool util_queue_init(struct util_queue *queue,
 221                      const char *name,
 222                      unsigned max_jobs,
 223                      unsigned num_threads,
 224                      unsigned flags);
 225 void util_queue_destroy(struct util_queue *queue);
 226
 227 /* optional cleanup callback is called after fence is signaled: */
 228 void util_queue_add_job(struct util_queue *queue,
 229                         void *job,
 230                         struct util_queue_fence *fence,
 231                         util_queue_execute_func execute,
 232                         util_queue_execute_func cleanup);
 233 void util_queue_drop_job(struct util_queue *queue,
 234                          struct util_queue_fence *fence);
 235
 236 void util_queue_finish(struct util_queue *queue);
 237
 238 int64_t util_queue_get_thread_time_nano(struct util_queue *queue,
 239                                         unsigned thread_index);
 240
 241 /* util_queue needs to be cleared to zeroes for this to work */
 242 static inline bool
 243 util_queue_is_initialized(struct util_queue *queue)
 244 {
 245    return queue->threads != NULL;
 246 }
 247
 248 /* Convenient structure for monitoring the queue externally and passing
 249  * the structure between Mesa components. The queue doesn't use it directly.
 250  */
 251 struct util_queue_monitoring
 252 {
 253    /* For querying the thread busyness. */
 254    struct util_queue *queue;
 255
 256    /* Counters updated by the user of the queue. */
 257    unsigned num_offloaded_items;
 258    unsigned num_direct_items;
 259    unsigned num_syncs;
 260 };
 261
 262 #ifdef __cplusplus
 263 }
 264 #endif
 265
 266 #endif