src/mesa/drivers/dri/i965/gen6_queryobj.c

   1 /*
   2  * Copyright © 2008 Intel Corporation
   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  * Authors:
  24  *    Eric Anholt <eric@anholt.net>
  25  *    Kenneth Graunke <kenneth@whitecape.org>
  26  */
  27
  28 /** @file gen6_queryobj.c
  29  *
  30  * Support for query objects (GL_ARB_occlusion_query, GL_ARB_timer_query,
  31  * GL_EXT_transform_feedback, and friends) on platforms that support
  32  * hardware contexts (Gen6+).
  33  */
  34 #include "main/imports.h"
  35
  36 #include "brw_context.h"
  37 #include "brw_defines.h"
  38 #include "brw_state.h"
  39 #include "intel_batchbuffer.h"
  40 #include "intel_reg.h"
  41
  42 static void
  43 write_primitives_generated(struct brw_context *brw,
  44                            drm_intel_bo *query_bo, int stream, int idx)
  45 {
  46    brw_emit_mi_flush(brw);
  47
  48    if (brw->gen >= 7 && stream > 0) {
  49       brw_store_register_mem64(brw, query_bo,
  50                                GEN7_SO_PRIM_STORAGE_NEEDED(stream),
  51                                idx * sizeof(uint64_t));
  52    } else {
  53       brw_store_register_mem64(brw, query_bo, CL_INVOCATION_COUNT,
  54                                idx * sizeof(uint64_t));
  55    }
  56 }
  57
  58 static void
  59 write_xfb_primitives_written(struct brw_context *brw,
  60                              drm_intel_bo *bo, int stream, int idx)
  61 {
  62    brw_emit_mi_flush(brw);
  63
  64    if (brw->gen >= 7) {
  65       brw_store_register_mem64(brw, bo, GEN7_SO_NUM_PRIMS_WRITTEN(stream),
  66                                idx * sizeof(uint64_t));
  67    } else {
  68       brw_store_register_mem64(brw, bo, GEN6_SO_NUM_PRIMS_WRITTEN,
  69                                idx * sizeof(uint64_t));
  70    }
  71 }
  72
  73 static inline const int
  74 pipeline_target_to_index(int target)
  75 {
  76    if (target == GL_GEOMETRY_SHADER_INVOCATIONS)
  77       return MAX_PIPELINE_STATISTICS - 1;
  78    else
  79       return target - GL_VERTICES_SUBMITTED_ARB;
  80 }
  81
  82 static void
  83 emit_pipeline_stat(struct brw_context *brw, drm_intel_bo *bo,
  84                    int stream, int target, int idx)
  85 {
  86    /* One source of confusion is the tessellation shader statistics. The
  87     * hardware has no statistics specific to the TE unit. Ideally we could have
  88     * the HS primitives for TESS_CONTROL_SHADER_PATCHES_ARB, and the DS
  89     * invocations as the register for TESS_CONTROL_SHADER_PATCHES_ARB.
  90     * Unfortunately we don't have HS primitives, we only have HS invocations.
  91     */
  92
  93    /* Everything except GEOMETRY_SHADER_INVOCATIONS can be kept in a simple
  94     * lookup table
  95     */
  96    static const uint32_t target_to_register[] = {
  97       IA_VERTICES_COUNT,   /* VERTICES_SUBMITTED */
  98       IA_PRIMITIVES_COUNT, /* PRIMITIVES_SUBMITTED */
  99       VS_INVOCATION_COUNT, /* VERTEX_SHADER_INVOCATIONS */
 100       HS_INVOCATION_COUNT, /* TESS_CONTROL_SHADER_PATCHES */
 101       DS_INVOCATION_COUNT, /* TESS_EVALUATION_SHADER_INVOCATIONS */
 102       GS_PRIMITIVES_COUNT, /* GEOMETRY_SHADER_PRIMITIVES_EMITTED */
 103       PS_INVOCATION_COUNT, /* FRAGMENT_SHADER_INVOCATIONS */
 104       CS_INVOCATION_COUNT, /* COMPUTE_SHADER_INVOCATIONS */
 105       CL_INVOCATION_COUNT, /* CLIPPING_INPUT_PRIMITIVES */
 106       CL_PRIMITIVES_COUNT, /* CLIPPING_OUTPUT_PRIMITIVES */
 107       GS_INVOCATION_COUNT /* This one is special... */
 108    };
 109    STATIC_ASSERT(ARRAY_SIZE(target_to_register) == MAX_PIPELINE_STATISTICS);
 110    uint32_t reg = target_to_register[pipeline_target_to_index(target)];
 111    /* Gen6 GS code counts full primitives, that is, it won't count individual
 112     * triangles in a triangle strip. Use CL_INVOCATION_COUNT for that.
 113     */
 114    if (brw->gen == 6 && target == GL_GEOMETRY_SHADER_PRIMITIVES_EMITTED_ARB)
 115       reg = CL_INVOCATION_COUNT;
 116    assert(reg != 0);
 117
 118    /* Emit a flush to make sure various parts of the pipeline are complete and
 119     * we get an accurate value
 120     */
 121    brw_emit_mi_flush(brw);
 122
 123    brw_store_register_mem64(brw, bo, reg, idx * sizeof(uint64_t));
 124 }
 125
 126
 127 /**
 128  * Wait on the query object's BO and calculate the final result.
 129  */
 130 static void
 131 gen6_queryobj_get_results(struct gl_context *ctx,
 132                           struct brw_query_object *query)
 133 {
 134    struct brw_context *brw = brw_context(ctx);
 135
 136    if (query->bo == NULL)
 137       return;
 138
 139    brw_bo_map(brw, query->bo, false, "query object");
 140    uint64_t *results = query->bo->virtual;
 141    switch (query->Base.Target) {
 142    case GL_TIME_ELAPSED:
 143       /* The query BO contains the starting and ending timestamps.
 144        * Subtract the two and convert to nanoseconds.
 145        */
 146       query->Base.Result += 80 * (results[1] - results[0]);
 147       break;
 148
 149    case GL_TIMESTAMP:
 150       /* Our timer is a clock that increments every 80ns (regardless of
 151        * other clock scaling in the system).  The timestamp register we can
 152        * read for glGetTimestamp() masks out the top 32 bits, so we do that
 153        * here too to let the two counters be compared against each other.
 154        *
 155        * If we just multiplied that 32 bits of data by 80, it would roll
 156        * over at a non-power-of-two, so an application couldn't use
 157        * GL_QUERY_COUNTER_BITS to handle rollover correctly.  Instead, we
 158        * report 36 bits and truncate at that (rolling over 5 times as often
 159        * as the HW counter), and when the 32-bit counter rolls over, it
 160        * happens to also be at a rollover in the reported value from near
 161        * (1<<36) to 0.
 162        *
 163        * The low 32 bits rolls over in ~343 seconds.  Our 36-bit result
 164        * rolls over every ~69 seconds.
 165        *
 166        * The query BO contains a single timestamp value in results[0].
 167        */
 168       query->Base.Result = 80 * (results[0] & 0xffffffff);
 169       query->Base.Result &= (1ull << 36) - 1;
 170       break;
 171
 172    case GL_SAMPLES_PASSED_ARB:
 173       /* We need to use += rather than = here since some BLT-based operations
 174        * may have added additional samples to our occlusion query value.
 175        */
 176       query->Base.Result += results[1] - results[0];
 177       break;
 178
 179    case GL_ANY_SAMPLES_PASSED:
 180    case GL_ANY_SAMPLES_PASSED_CONSERVATIVE:
 181       if (results[0] != results[1])
 182          query->Base.Result = true;
 183       break;
 184
 185    case GL_PRIMITIVES_GENERATED:
 186    case GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN:
 187    case GL_VERTICES_SUBMITTED_ARB:
 188    case GL_PRIMITIVES_SUBMITTED_ARB:
 189    case GL_VERTEX_SHADER_INVOCATIONS_ARB:
 190    case GL_GEOMETRY_SHADER_INVOCATIONS:
 191    case GL_GEOMETRY_SHADER_PRIMITIVES_EMITTED_ARB:
 192    case GL_CLIPPING_INPUT_PRIMITIVES_ARB:
 193    case GL_CLIPPING_OUTPUT_PRIMITIVES_ARB:
 194    case GL_COMPUTE_SHADER_INVOCATIONS_ARB:
 195    case GL_TESS_CONTROL_SHADER_PATCHES_ARB:
 196    case GL_TESS_EVALUATION_SHADER_INVOCATIONS_ARB:
 197       query->Base.Result = results[1] - results[0];
 198       break;
 199
 200    case GL_FRAGMENT_SHADER_INVOCATIONS_ARB:
 201       query->Base.Result = (results[1] - results[0]);
 202       /* Implement the "WaDividePSInvocationCountBy4:HSW,BDW" workaround:
 203        * "Invocation counter is 4 times actual.  WA: SW to divide HW reported
 204        *  PS Invocations value by 4."
 205        *
 206        * Prior to Haswell, invocation count was counted by the WM, and it
 207        * buggily counted invocations in units of subspans (2x2 unit). To get the
 208        * correct value, the CS multiplied this by 4. With HSW the logic moved,
 209        * and correctly emitted the number of pixel shader invocations, but,
 210        * whomever forgot to undo the multiply by 4.
 211        */
 212       if (brw->gen == 8 || brw->is_haswell)
 213          query->Base.Result /= 4;
 214       break;
 215
 216    default:
 217       unreachable("Unrecognized query target in brw_queryobj_get_results()");
 218    }
 219    drm_intel_bo_unmap(query->bo);
 220
 221    /* Now that we've processed the data stored in the query's buffer object,
 222     * we can release it.
 223     */
 224    drm_intel_bo_unreference(query->bo);
 225    query->bo = NULL;
 226
 227    query->Base.Ready = true;
 228 }
 229
 230 /**
 231  * Driver hook for glBeginQuery().
 232  *
 233  * Initializes driver structures and emits any GPU commands required to begin
 234  * recording data for the query.
 235  */
 236 static void
 237 gen6_begin_query(struct gl_context *ctx, struct gl_query_object *q)
 238 {
 239    struct brw_context *brw = brw_context(ctx);
 240    struct brw_query_object *query = (struct brw_query_object *)q;
 241
 242    /* Since we're starting a new query, we need to throw away old results. */
 243    drm_intel_bo_unreference(query->bo);
 244    query->bo = drm_intel_bo_alloc(brw->bufmgr, "query results", 4096, 4096);
 245
 246    switch (query->Base.Target) {
 247    case GL_TIME_ELAPSED:
 248       /* For timestamp queries, we record the starting time right away so that
 249        * we measure the full time between BeginQuery and EndQuery.  There's
 250        * some debate about whether this is the right thing to do.  Our decision
 251        * is based on the following text from the ARB_timer_query extension:
 252        *
 253        * "(5) Should the extension measure total time elapsed between the full
 254        *      completion of the BeginQuery and EndQuery commands, or just time
 255        *      spent in the graphics library?
 256        *
 257        *  RESOLVED:  This extension will measure the total time elapsed
 258        *  between the full completion of these commands.  Future extensions
 259        *  may implement a query to determine time elapsed at different stages
 260        *  of the graphics pipeline."
 261        *
 262        * We write a starting timestamp now (at index 0).  At EndQuery() time,
 263        * we'll write a second timestamp (at index 1), and subtract the two to
 264        * obtain the time elapsed.  Notably, this includes time elapsed while
 265        * the system was doing other work, such as running other applications.
 266        */
 267       brw_write_timestamp(brw, query->bo, 0);
 268       break;
 269
 270    case GL_ANY_SAMPLES_PASSED:
 271    case GL_ANY_SAMPLES_PASSED_CONSERVATIVE:
 272    case GL_SAMPLES_PASSED_ARB:
 273       brw_write_depth_count(brw, query->bo, 0);
 274       break;
 275
 276    case GL_PRIMITIVES_GENERATED:
 277       write_primitives_generated(brw, query->bo, query->Base.Stream, 0);
 278       break;
 279
 280    case GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN:
 281       write_xfb_primitives_written(brw, query->bo, query->Base.Stream, 0);
 282       break;
 283
 284    case GL_VERTICES_SUBMITTED_ARB:
 285    case GL_PRIMITIVES_SUBMITTED_ARB:
 286    case GL_VERTEX_SHADER_INVOCATIONS_ARB:
 287    case GL_GEOMETRY_SHADER_INVOCATIONS:
 288    case GL_GEOMETRY_SHADER_PRIMITIVES_EMITTED_ARB:
 289    case GL_FRAGMENT_SHADER_INVOCATIONS_ARB:
 290    case GL_CLIPPING_INPUT_PRIMITIVES_ARB:
 291    case GL_CLIPPING_OUTPUT_PRIMITIVES_ARB:
 292    case GL_COMPUTE_SHADER_INVOCATIONS_ARB:
 293    case GL_TESS_CONTROL_SHADER_PATCHES_ARB:
 294    case GL_TESS_EVALUATION_SHADER_INVOCATIONS_ARB:
 295       emit_pipeline_stat(brw, query->bo, query->Base.Stream, query->Base.Target, 0);
 296       break;
 297
 298    default:
 299       unreachable("Unrecognized query target in brw_begin_query()");
 300    }
 301 }
 302
 303 /**
 304  * Driver hook for glEndQuery().
 305  *
 306  * Emits GPU commands to record a final query value, ending any data capturing.
 307  * However, the final result isn't necessarily available until the GPU processes
 308  * those commands.  brw_queryobj_get_results() processes the captured data to
 309  * produce the final result.
 310  */
 311 static void
 312 gen6_end_query(struct gl_context *ctx, struct gl_query_object *q)
 313 {
 314    struct brw_context *brw = brw_context(ctx);
 315    struct brw_query_object *query = (struct brw_query_object *)q;
 316
 317    switch (query->Base.Target) {
 318    case GL_TIME_ELAPSED:
 319       brw_write_timestamp(brw, query->bo, 1);
 320       break;
 321
 322    case GL_ANY_SAMPLES_PASSED:
 323    case GL_ANY_SAMPLES_PASSED_CONSERVATIVE:
 324    case GL_SAMPLES_PASSED_ARB:
 325       brw_write_depth_count(brw, query->bo, 1);
 326       break;
 327
 328    case GL_PRIMITIVES_GENERATED:
 329       write_primitives_generated(brw, query->bo, query->Base.Stream, 1);
 330       break;
 331
 332    case GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN:
 333       write_xfb_primitives_written(brw, query->bo, query->Base.Stream, 1);
 334       break;
 335
 336    case GL_VERTICES_SUBMITTED_ARB:
 337    case GL_PRIMITIVES_SUBMITTED_ARB:
 338    case GL_VERTEX_SHADER_INVOCATIONS_ARB:
 339    case GL_GEOMETRY_SHADER_PRIMITIVES_EMITTED_ARB:
 340    case GL_FRAGMENT_SHADER_INVOCATIONS_ARB:
 341    case GL_COMPUTE_SHADER_INVOCATIONS_ARB:
 342    case GL_CLIPPING_INPUT_PRIMITIVES_ARB:
 343    case GL_CLIPPING_OUTPUT_PRIMITIVES_ARB:
 344    case GL_GEOMETRY_SHADER_INVOCATIONS:
 345    case GL_TESS_CONTROL_SHADER_PATCHES_ARB:
 346    case GL_TESS_EVALUATION_SHADER_INVOCATIONS_ARB:
 347       emit_pipeline_stat(brw, query->bo,
 348                          query->Base.Stream, query->Base.Target, 1);
 349       break;
 350
 351    default:
 352       unreachable("Unrecognized query target in brw_end_query()");
 353    }
 354
 355    /* The current batch contains the commands to handle EndQuery(),
 356     * but they won't actually execute until it is flushed.
 357     */
 358    query->flushed = false;
 359 }
 360
 361 /**
 362  * Flush the batch if it still references the query object BO.
 363  */
 364 static void
 365 flush_batch_if_needed(struct brw_context *brw, struct brw_query_object *query)
 366 {
 367    /* If the batch doesn't reference the BO, it must have been flushed
 368     * (for example, due to being full).  Record that it's been flushed.
 369     */
 370    query->flushed = query->flushed ||
 371       !drm_intel_bo_references(brw->batch.bo, query->bo);
 372
 373    if (!query->flushed)
 374       intel_batchbuffer_flush(brw);
 375 }
 376
 377 /**
 378  * The WaitQuery() driver hook.
 379  *
 380  * Wait for a query result to become available and return it.  This is the
 381  * backing for glGetQueryObjectiv() with the GL_QUERY_RESULT pname.
 382  */
 383 static void gen6_wait_query(struct gl_context *ctx, struct gl_query_object *q)
 384 {
 385    struct brw_context *brw = brw_context(ctx);
 386    struct brw_query_object *query = (struct brw_query_object *)q;
 387
 388    /* If the application has requested the query result, but this batch is
 389     * still contributing to it, flush it now to finish that work so the
 390     * result will become available (eventually).
 391     */
 392    flush_batch_if_needed(brw, query);
 393
 394    gen6_queryobj_get_results(ctx, query);
 395 }
 396
 397 /**
 398  * The CheckQuery() driver hook.
 399  *
 400  * Checks whether a query result is ready yet.  If not, flushes.
 401  * This is the backing for glGetQueryObjectiv()'s QUERY_RESULT_AVAILABLE pname.
 402  */
 403 static void gen6_check_query(struct gl_context *ctx, struct gl_query_object *q)
 404 {
 405    struct brw_context *brw = brw_context(ctx);
 406    struct brw_query_object *query = (struct brw_query_object *)q;
 407
 408    /* If query->bo is NULL, we've already gathered the results - this is a
 409     * redundant CheckQuery call.  Ignore it.
 410     */
 411    if (query->bo == NULL)
 412       return;
 413
 414    /* From the GL_ARB_occlusion_query spec:
 415     *
 416     *     "Instead of allowing for an infinite loop, performing a
 417     *      QUERY_RESULT_AVAILABLE_ARB will perform a flush if the result is
 418     *      not ready yet on the first time it is queried.  This ensures that
 419     *      the async query will return true in finite time.
 420     */
 421    flush_batch_if_needed(brw, query);
 422
 423    if (!drm_intel_bo_busy(query->bo)) {
 424       gen6_queryobj_get_results(ctx, query);
 425    }
 426 }
 427
 428 /* Initialize Gen6+-specific query object functions. */
 429 void gen6_init_queryobj_functions(struct dd_function_table *functions)
 430 {
 431    functions->BeginQuery = gen6_begin_query;
 432    functions->EndQuery = gen6_end_query;
 433    functions->CheckQuery = gen6_check_query;
 434    functions->WaitQuery = gen6_wait_query;
 435 }