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 #define UTIL_QUEUE_INIT_SET_FULL_THREAD_AFFINITY  (1 << 2)
  52
  53 #if defined(__GNUC__) && defined(HAVE_LINUX_FUTEX_H)
  54 #define UTIL_QUEUE_FENCE_FUTEX
  55 #else
  56 #define UTIL_QUEUE_FENCE_STANDARD
  57 #endif
  58
  59 #ifdef UTIL_QUEUE_FENCE_FUTEX
  60 /* Job completion fence.
  61  * Put this into your job structure.
  62  */
  63 struct util_queue_fence {
  64    /* The fence can be in one of three states:
  65     *  0 - signaled
  66     *  1 - unsignaled
  67     *  2 - unsignaled, may have waiters
  68     */
  69    uint32_t val;
  70 };
  71
  72 static inline void
  73 util_queue_fence_init(struct util_queue_fence *fence)
  74 {
  75    fence->val = 0;
  76 }
  77
  78 static inline void
  79 util_queue_fence_destroy(struct util_queue_fence *fence)
  80 {
  81    assert(fence->val == 0);
  82    /* no-op */
  83 }
  84
  85 static inline void
  86 util_queue_fence_signal(struct util_queue_fence *fence)
  87 {
  88    uint32_t val = p_atomic_xchg(&fence->val, 0);
  89
  90    assert(val != 0);
  91
  92    if (val == 2)
  93       futex_wake(&fence->val, INT_MAX);
  94 }
  95
  96 /**
  97  * Move \p fence back into unsignalled state.
  98  *
  99  * \warning The caller must ensure that no other thread may currently be
 100  *          waiting (or about to wait) on the fence.
 101  */
 102 static inline void
 103 util_queue_fence_reset(struct util_queue_fence *fence)
 104 {
 105 #ifdef NDEBUG
 106    fence->val = 1;
 107 #else
 108    uint32_t v = p_atomic_xchg(&fence->val, 1);
 109    assert(v == 0);
 110 #endif
 111 }
 112
 113 static inline bool
 114 util_queue_fence_is_signalled(struct util_queue_fence *fence)
 115 {
 116    return fence->val == 0;
 117 }
 118 #endif
 119
 120 #ifdef UTIL_QUEUE_FENCE_STANDARD
 121 /* Job completion fence.
 122  * Put this into your job structure.
 123  */
 124 struct util_queue_fence {
 125    mtx_t mutex;
 126    cnd_t cond;
 127    int signalled;
 128 };
 129
 130 void util_queue_fence_init(struct util_queue_fence *fence);
 131 void util_queue_fence_destroy(struct util_queue_fence *fence);
 132 void util_queue_fence_signal(struct util_queue_fence *fence);
 133
 134 /**
 135  * Move \p fence back into unsignalled state.
 136  *
 137  * \warning The caller must ensure that no other thread may currently be
 138  *          waiting (or about to wait) on the fence.
 139  */
 140 static inline void
 141 util_queue_fence_reset(struct util_queue_fence *fence)
 142 {
 143    assert(fence->signalled);
 144    fence->signalled = 0;
 145 }
 146
 147 static inline bool
 148 util_queue_fence_is_signalled(struct util_queue_fence *fence)
 149 {
 150    return fence->signalled != 0;
 151 }
 152 #endif
 153
 154 void
 155 _util_queue_fence_wait(struct util_queue_fence *fence);
 156
 157 static inline void
 158 util_queue_fence_wait(struct util_queue_fence *fence)
 159 {
 160    if (unlikely(!util_queue_fence_is_signalled(fence)))
 161       _util_queue_fence_wait(fence);
 162 }
 163
 164 bool
 165 _util_queue_fence_wait_timeout(struct util_queue_fence *fence,
 166                                int64_t abs_timeout);
 167
 168 /**
 169  * Wait for the fence to be signaled with a timeout.
 170  *
 171  * \param fence the fence
 172  * \param abs_timeout the absolute timeout in nanoseconds, relative to the
 173  *                    clock provided by os_time_get_nano.
 174  *
 175  * \return true if the fence was signaled, false if the timeout occurred.
 176  */
 177 static inline bool
 178 util_queue_fence_wait_timeout(struct util_queue_fence *fence,
 179                               int64_t abs_timeout)
 180 {
 181    if (util_queue_fence_is_signalled(fence))
 182       return true;
 183
 184    if (abs_timeout == (int64_t)OS_TIMEOUT_INFINITE) {
 185       _util_queue_fence_wait(fence);
 186       return true;
 187    }
 188
 189    return _util_queue_fence_wait_timeout(fence, abs_timeout);
 190 }
 191
 192 typedef void (*util_queue_execute_func)(void *job, int thread_index);
 193
 194 struct util_queue_job {
 195    void *job;
 196    size_t job_size;
 197    struct util_queue_fence *fence;
 198    util_queue_execute_func execute;
 199    util_queue_execute_func cleanup;
 200 };
 201
 202 /* Put this into your context. */
 203 struct util_queue {
 204    char name[14]; /* 13 characters = the thread name without the index */
 205    mtx_t finish_lock; /* for util_queue_finish and protects threads/num_threads */
 206    mtx_t lock;
 207    cnd_t has_queued_cond;
 208    cnd_t has_space_cond;
 209    thrd_t *threads;
 210    unsigned flags;
 211    int num_queued;
 212    unsigned max_threads;
 213    unsigned num_threads; /* decreasing this number will terminate threads */
 214    int max_jobs;
 215    int write_idx, read_idx; /* ring buffer pointers */
 216    size_t total_jobs_size;  /* memory use of all jobs in the queue */
 217    struct util_queue_job *jobs;
 218
 219    /* for cleanup at exit(), protected by exit_mutex */
 220    struct list_head head;
 221 };
 222
 223 bool util_queue_init(struct util_queue *queue,
 224                      const char *name,
 225                      unsigned max_jobs,
 226                      unsigned num_threads,
 227                      unsigned flags);
 228 void util_queue_destroy(struct util_queue *queue);
 229
 230 /* optional cleanup callback is called after fence is signaled: */
 231 void util_queue_add_job(struct util_queue *queue,
 232                         void *job,
 233                         struct util_queue_fence *fence,
 234                         util_queue_execute_func execute,
 235                         util_queue_execute_func cleanup,
 236                         const size_t job_size);
 237 void util_queue_drop_job(struct util_queue *queue,
 238                          struct util_queue_fence *fence);
 239
 240 void util_queue_finish(struct util_queue *queue);
 241
 242 /* Adjust the number of active threads. The new number of threads can't be
 243  * greater than the initial number of threads at the creation of the queue,
 244  * and it can't be less than 1.
 245  */
 246 void
 247 util_queue_adjust_num_threads(struct util_queue *queue, unsigned num_threads);
 248
 249 int64_t util_queue_get_thread_time_nano(struct util_queue *queue,
 250                                         unsigned thread_index);
 251
 252 /* util_queue needs to be cleared to zeroes for this to work */
 253 static inline bool
 254 util_queue_is_initialized(struct util_queue *queue)
 255 {
 256    return queue->threads != NULL;
 257 }
 258
 259 /* Convenient structure for monitoring the queue externally and passing
 260  * the structure between Mesa components. The queue doesn't use it directly.
 261  */
 262 struct util_queue_monitoring
 263 {
 264    /* For querying the thread busyness. */
 265    struct util_queue *queue;
 266
 267    /* Counters updated by the user of the queue. */
 268    unsigned num_offloaded_items;
 269    unsigned num_direct_items;
 270    unsigned num_syncs;
 271 };
 272
 273 #ifdef __cplusplus
 274 }
 275 #endif
 276
 277 #endif