2 * Copyright © 2008 Intel Corporation
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:
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
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
24 * Eric Anholt <eric@anholt.net>
28 /** @file brw_queryobj.c
30 * Support for query objects (GL_ARB_occlusion_query, GL_ARB_timer_query,
31 * GL_EXT_transform_feedback, and friends).
33 * The hardware provides a PIPE_CONTROL command that can report the number of
34 * fragments that passed the depth test, or the hardware timer. They are
35 * appropriately synced with the stage of the pipeline for our extensions'
38 #include "main/imports.h"
40 #include "brw_context.h"
41 #include "brw_defines.h"
42 #include "brw_state.h"
43 #include "intel_batchbuffer.h"
46 brw_timebase_scale(struct brw_context
*brw
, uint64_t gpu_timestamp
)
48 const struct gen_device_info
*devinfo
= &brw
->screen
->devinfo
;
50 return (1000000000ull * gpu_timestamp
) / devinfo
->timestamp_frequency
;
53 /* As best we know currently, the Gen HW timestamps are 36bits across
54 * all platforms, which we need to account for when calculating a
55 * delta to measure elapsed time.
57 * The timestamps read via glGetTimestamp() / brw_get_timestamp() sometimes
58 * only have 32bits due to a kernel bug and so in that case we make sure to
59 * treat all raw timestamps as 32bits so they overflow consistently and remain
60 * comparable. (Note: the timestamps being passed here are not from the kernel
61 * so we don't need to be taking the upper 32bits in this buggy kernel case we
62 * are just clipping to 32bits here for consistency.)
65 brw_raw_timestamp_delta(struct brw_context
*brw
, uint64_t time0
, uint64_t time1
)
67 if (brw
->screen
->hw_has_timestamp
== 2) {
68 /* Kernel clips timestamps to 32bits in this case, so we also clip
69 * PIPE_CONTROL timestamps for consistency.
71 return (uint32_t)time1
- (uint32_t)time0
;
74 return (1ULL << 36) + time1
- time0
;
82 * Emit PIPE_CONTROLs to write the current GPU timestamp into a buffer.
85 brw_write_timestamp(struct brw_context
*brw
, struct brw_bo
*query_bo
, int idx
)
87 const struct gen_device_info
*devinfo
= &brw
->screen
->devinfo
;
89 if (devinfo
->gen
== 6) {
90 /* Emit Sandybridge workaround flush: */
91 brw_emit_pipe_control_flush(brw
,
92 PIPE_CONTROL_CS_STALL
|
93 PIPE_CONTROL_STALL_AT_SCOREBOARD
);
96 uint32_t flags
= PIPE_CONTROL_WRITE_TIMESTAMP
;
98 if (devinfo
->gen
== 9 && devinfo
->gt
== 4)
99 flags
|= PIPE_CONTROL_CS_STALL
;
101 brw_emit_pipe_control_write(brw
, flags
,
102 query_bo
, idx
* sizeof(uint64_t), 0);
106 * Emit PIPE_CONTROLs to write the PS_DEPTH_COUNT register into a buffer.
109 brw_write_depth_count(struct brw_context
*brw
, struct brw_bo
*query_bo
, int idx
)
111 const struct gen_device_info
*devinfo
= &brw
->screen
->devinfo
;
112 uint32_t flags
= PIPE_CONTROL_WRITE_DEPTH_COUNT
| PIPE_CONTROL_DEPTH_STALL
;
114 if (devinfo
->gen
== 9 && devinfo
->gt
== 4)
115 flags
|= PIPE_CONTROL_CS_STALL
;
117 if (devinfo
->gen
>= 10) {
118 /* "Driver must program PIPE_CONTROL with only Depth Stall Enable bit set
119 * prior to programming a PIPE_CONTROL with Write PS Depth Count Post sync
122 brw_emit_pipe_control_flush(brw
, PIPE_CONTROL_DEPTH_STALL
);
125 brw_emit_pipe_control_write(brw
, flags
,
126 query_bo
, idx
* sizeof(uint64_t), 0);
130 * Wait on the query object's BO and calculate the final result.
133 brw_queryobj_get_results(struct gl_context
*ctx
,
134 struct brw_query_object
*query
)
136 struct brw_context
*brw
= brw_context(ctx
);
137 const struct gen_device_info
*devinfo
= &brw
->screen
->devinfo
;
142 assert(devinfo
->gen
< 6);
144 if (query
->bo
== NULL
)
147 /* If the application has requested the query result, but this batch is
148 * still contributing to it, flush it now so the results will be present
151 if (brw_batch_references(&brw
->batch
, query
->bo
))
152 intel_batchbuffer_flush(brw
);
154 if (unlikely(brw
->perf_debug
)) {
155 if (brw_bo_busy(query
->bo
)) {
156 perf_debug("Stalling on the GPU waiting for a query object.\n");
160 results
= brw_bo_map(brw
, query
->bo
, MAP_READ
);
161 switch (query
->Base
.Target
) {
162 case GL_TIME_ELAPSED_EXT
:
163 /* The query BO contains the starting and ending timestamps.
164 * Subtract the two and convert to nanoseconds.
166 query
->Base
.Result
= brw_raw_timestamp_delta(brw
, results
[0], results
[1]);
167 query
->Base
.Result
= brw_timebase_scale(brw
, query
->Base
.Result
);
171 /* The query BO contains a single timestamp value in results[0]. */
172 query
->Base
.Result
= brw_timebase_scale(brw
, results
[0]);
174 /* Ensure the scaled timestamp overflows according to
175 * GL_QUERY_COUNTER_BITS
177 query
->Base
.Result
&= (1ull << ctx
->Const
.QueryCounterBits
.Timestamp
) - 1;
180 case GL_SAMPLES_PASSED_ARB
:
181 /* Loop over pairs of values from the BO, which are the PS_DEPTH_COUNT
182 * value at the start and end of the batchbuffer. Subtract them to
183 * get the number of fragments which passed the depth test in each
184 * individual batch, and add those differences up to get the number
185 * of fragments for the entire query.
187 * Note that query->Base.Result may already be non-zero. We may have
188 * run out of space in the query's BO and allocated a new one. If so,
189 * this function was already called to accumulate the results so far.
191 for (i
= 0; i
< query
->last_index
; i
++) {
192 query
->Base
.Result
+= results
[i
* 2 + 1] - results
[i
* 2];
196 case GL_ANY_SAMPLES_PASSED
:
197 case GL_ANY_SAMPLES_PASSED_CONSERVATIVE
:
198 /* If the starting and ending PS_DEPTH_COUNT from any of the batches
199 * differ, then some fragments passed the depth test.
201 for (i
= 0; i
< query
->last_index
; i
++) {
202 if (results
[i
* 2 + 1] != results
[i
* 2]) {
203 query
->Base
.Result
= GL_TRUE
;
210 unreachable("Unrecognized query target in brw_queryobj_get_results()");
212 brw_bo_unmap(query
->bo
);
214 /* Now that we've processed the data stored in the query's buffer object,
217 brw_bo_unreference(query
->bo
);
222 * The NewQueryObject() driver hook.
224 * Allocates and initializes a new query object.
226 static struct gl_query_object
*
227 brw_new_query_object(struct gl_context
*ctx
, GLuint id
)
229 struct brw_query_object
*query
;
231 query
= calloc(1, sizeof(struct brw_query_object
));
234 query
->Base
.Result
= 0;
235 query
->Base
.Active
= false;
236 query
->Base
.Ready
= true;
242 * The DeleteQuery() driver hook.
245 brw_delete_query(struct gl_context
*ctx
, struct gl_query_object
*q
)
247 struct brw_query_object
*query
= (struct brw_query_object
*)q
;
249 brw_bo_unreference(query
->bo
);
254 * Gen4-5 driver hook for glBeginQuery().
256 * Initializes driver structures and emits any GPU commands required to begin
257 * recording data for the query.
260 brw_begin_query(struct gl_context
*ctx
, struct gl_query_object
*q
)
262 struct brw_context
*brw
= brw_context(ctx
);
263 struct brw_query_object
*query
= (struct brw_query_object
*)q
;
264 const struct gen_device_info
*devinfo
= &brw
->screen
->devinfo
;
266 assert(devinfo
->gen
< 6);
268 switch (query
->Base
.Target
) {
269 case GL_TIME_ELAPSED_EXT
:
270 /* For timestamp queries, we record the starting time right away so that
271 * we measure the full time between BeginQuery and EndQuery. There's
272 * some debate about whether this is the right thing to do. Our decision
273 * is based on the following text from the ARB_timer_query extension:
275 * "(5) Should the extension measure total time elapsed between the full
276 * completion of the BeginQuery and EndQuery commands, or just time
277 * spent in the graphics library?
279 * RESOLVED: This extension will measure the total time elapsed
280 * between the full completion of these commands. Future extensions
281 * may implement a query to determine time elapsed at different stages
282 * of the graphics pipeline."
284 * We write a starting timestamp now (at index 0). At EndQuery() time,
285 * we'll write a second timestamp (at index 1), and subtract the two to
286 * obtain the time elapsed. Notably, this includes time elapsed while
287 * the system was doing other work, such as running other applications.
289 brw_bo_unreference(query
->bo
);
290 query
->bo
= brw_bo_alloc(brw
->bufmgr
, "timer query", 4096, 4096);
291 brw_write_timestamp(brw
, query
->bo
, 0);
294 case GL_ANY_SAMPLES_PASSED
:
295 case GL_ANY_SAMPLES_PASSED_CONSERVATIVE
:
296 case GL_SAMPLES_PASSED_ARB
:
297 /* For occlusion queries, we delay taking an initial sample until the
298 * first drawing occurs in this batch. See the reasoning in the comments
299 * for brw_emit_query_begin() below.
301 * Since we're starting a new query, we need to be sure to throw away
302 * any previous occlusion query results.
304 brw_bo_unreference(query
->bo
);
306 query
->last_index
= -1;
308 brw
->query
.obj
= query
;
310 /* Depth statistics on Gen4 require strange workarounds, so we try to
311 * avoid them when necessary. They're required for occlusion queries,
312 * so turn them on now.
315 brw
->ctx
.NewDriverState
|= BRW_NEW_STATS_WM
;
319 unreachable("Unrecognized query target in brw_begin_query()");
324 * Gen4-5 driver hook for glEndQuery().
326 * Emits GPU commands to record a final query value, ending any data capturing.
327 * However, the final result isn't necessarily available until the GPU processes
328 * those commands. brw_queryobj_get_results() processes the captured data to
329 * produce the final result.
332 brw_end_query(struct gl_context
*ctx
, struct gl_query_object
*q
)
334 struct brw_context
*brw
= brw_context(ctx
);
335 struct brw_query_object
*query
= (struct brw_query_object
*)q
;
336 const struct gen_device_info
*devinfo
= &brw
->screen
->devinfo
;
338 assert(devinfo
->gen
< 6);
340 switch (query
->Base
.Target
) {
341 case GL_TIME_ELAPSED_EXT
:
342 /* Write the final timestamp. */
343 brw_write_timestamp(brw
, query
->bo
, 1);
346 case GL_ANY_SAMPLES_PASSED
:
347 case GL_ANY_SAMPLES_PASSED_CONSERVATIVE
:
348 case GL_SAMPLES_PASSED_ARB
:
350 /* No query->bo means that EndQuery was called after BeginQuery with no
351 * intervening drawing. Rather than doing nothing at all here in this
352 * case, we emit the query_begin and query_end state to the
353 * hardware. This is to guarantee that waiting on the result of this
354 * empty state will cause all previous queries to complete at all, as
355 * required by the specification:
357 * It must always be true that if any query object
358 * returns a result available of TRUE, all queries of the
359 * same type issued prior to that query must also return
360 * TRUE. [Open GL 4.3 (Core Profile) Section 4.2.1]
363 brw_emit_query_begin(brw
);
368 brw_emit_query_end(brw
);
370 brw
->query
.obj
= NULL
;
373 brw
->ctx
.NewDriverState
|= BRW_NEW_STATS_WM
;
377 unreachable("Unrecognized query target in brw_end_query()");
382 * The Gen4-5 WaitQuery() driver hook.
384 * Wait for a query result to become available and return it. This is the
385 * backing for glGetQueryObjectiv() with the GL_QUERY_RESULT pname.
387 static void brw_wait_query(struct gl_context
*ctx
, struct gl_query_object
*q
)
389 struct brw_query_object
*query
= (struct brw_query_object
*)q
;
390 const struct gen_device_info
*devinfo
= &brw_context(ctx
)->screen
->devinfo
;
392 assert(devinfo
->gen
< 6);
394 brw_queryobj_get_results(ctx
, query
);
395 query
->Base
.Ready
= true;
399 * The Gen4-5 CheckQuery() driver hook.
401 * Checks whether a query result is ready yet. If not, flushes.
402 * This is the backing for glGetQueryObjectiv()'s QUERY_RESULT_AVAILABLE pname.
404 static void brw_check_query(struct gl_context
*ctx
, struct gl_query_object
*q
)
406 struct brw_context
*brw
= brw_context(ctx
);
407 struct brw_query_object
*query
= (struct brw_query_object
*)q
;
408 const struct gen_device_info
*devinfo
= &brw
->screen
->devinfo
;
410 assert(devinfo
->gen
< 6);
412 /* From the GL_ARB_occlusion_query spec:
414 * "Instead of allowing for an infinite loop, performing a
415 * QUERY_RESULT_AVAILABLE_ARB will perform a flush if the result is
416 * not ready yet on the first time it is queried. This ensures that
417 * the async query will return true in finite time.
419 if (query
->bo
&& brw_batch_references(&brw
->batch
, query
->bo
))
420 intel_batchbuffer_flush(brw
);
422 if (query
->bo
== NULL
|| !brw_bo_busy(query
->bo
)) {
423 brw_queryobj_get_results(ctx
, query
);
424 query
->Base
.Ready
= true;
429 * Ensure there query's BO has enough space to store a new pair of values.
431 * If not, gather the existing BO's results and create a new buffer of the
435 ensure_bo_has_space(struct gl_context
*ctx
, struct brw_query_object
*query
)
437 struct brw_context
*brw
= brw_context(ctx
);
438 const struct gen_device_info
*devinfo
= &brw
->screen
->devinfo
;
440 assert(devinfo
->gen
< 6);
442 if (!query
->bo
|| query
->last_index
* 2 + 1 >= 4096 / sizeof(uint64_t)) {
444 if (query
->bo
!= NULL
) {
445 /* The old query BO did not have enough space, so we allocated a new
446 * one. Gather the results so far (adding up the differences) and
447 * release the old BO.
449 brw_queryobj_get_results(ctx
, query
);
452 query
->bo
= brw_bo_alloc(brw
->bufmgr
, "query", 4096, 1);
453 query
->last_index
= 0;
458 * Record the PS_DEPTH_COUNT value (for occlusion queries) just before
461 * In a pre-hardware context world, the single PS_DEPTH_COUNT register is
462 * shared among all applications using the GPU. However, our query value
463 * needs to only include fragments generated by our application/GL context.
465 * To accommodate this, we record PS_DEPTH_COUNT at the start and end of
466 * each batchbuffer (technically, the first primitive drawn and flush time).
467 * Subtracting each pair of values calculates the change in PS_DEPTH_COUNT
468 * caused by a batchbuffer. Since there is no preemption inside batches,
469 * this is guaranteed to only measure the effects of our current application.
471 * Adding each of these differences (in case drawing is done over many batches)
472 * produces the final expected value.
474 * In a world with hardware contexts, PS_DEPTH_COUNT is saved and restored
475 * as part of the context state, so this is unnecessary, and skipped.
478 brw_emit_query_begin(struct brw_context
*brw
)
480 struct gl_context
*ctx
= &brw
->ctx
;
481 struct brw_query_object
*query
= brw
->query
.obj
;
483 /* Skip if we're not doing any queries, or we've already recorded the
484 * initial query value for this batchbuffer.
486 if (!query
|| brw
->query
.begin_emitted
)
489 ensure_bo_has_space(ctx
, query
);
491 brw_write_depth_count(brw
, query
->bo
, query
->last_index
* 2);
493 brw
->query
.begin_emitted
= true;
497 * Called at batchbuffer flush to get an ending PS_DEPTH_COUNT
498 * (for non-hardware context platforms).
500 * See the explanation in brw_emit_query_begin().
503 brw_emit_query_end(struct brw_context
*brw
)
505 struct brw_query_object
*query
= brw
->query
.obj
;
507 if (!brw
->query
.begin_emitted
)
510 brw_write_depth_count(brw
, query
->bo
, query
->last_index
* 2 + 1);
512 brw
->query
.begin_emitted
= false;
517 * Driver hook for glQueryCounter().
519 * This handles GL_TIMESTAMP queries, which perform a pipelined read of the
520 * current GPU time. This is unlike GL_TIME_ELAPSED, which measures the
521 * time while the query is active.
524 brw_query_counter(struct gl_context
*ctx
, struct gl_query_object
*q
)
526 struct brw_context
*brw
= brw_context(ctx
);
527 struct brw_query_object
*query
= (struct brw_query_object
*) q
;
529 assert(q
->Target
== GL_TIMESTAMP
);
531 brw_bo_unreference(query
->bo
);
532 query
->bo
= brw_bo_alloc(brw
->bufmgr
, "timestamp query", 4096, 4096);
533 brw_write_timestamp(brw
, query
->bo
, 0);
535 query
->flushed
= false;
539 * Read the TIMESTAMP register immediately (in a non-pipelined fashion).
541 * This is used to implement the GetTimestamp() driver hook.
544 brw_get_timestamp(struct gl_context
*ctx
)
546 struct brw_context
*brw
= brw_context(ctx
);
549 switch (brw
->screen
->hw_has_timestamp
) {
550 case 3: /* New kernel, always full 36bit accuracy */
551 brw_reg_read(brw
->bufmgr
, TIMESTAMP
| 1, &result
);
553 case 2: /* 64bit kernel, result is left-shifted by 32bits, losing 4bits */
554 brw_reg_read(brw
->bufmgr
, TIMESTAMP
, &result
);
555 result
= result
>> 32;
557 case 1: /* 32bit kernel, result is 36bit wide but may be inaccurate! */
558 brw_reg_read(brw
->bufmgr
, TIMESTAMP
, &result
);
562 /* Scale to nanosecond units */
563 result
= brw_timebase_scale(brw
, result
);
565 /* Ensure the scaled timestamp overflows according to
566 * GL_QUERY_COUNTER_BITS. Technically this isn't required if
567 * querying GL_TIMESTAMP via glGetInteger but it seems best to keep
568 * QueryObject and GetInteger timestamps consistent.
570 result
&= (1ull << ctx
->Const
.QueryCounterBits
.Timestamp
) - 1;
575 * Is this type of query written by PIPE_CONTROL?
578 brw_is_query_pipelined(struct brw_query_object
*query
)
580 switch (query
->Base
.Target
) {
582 case GL_TIME_ELAPSED
:
583 case GL_ANY_SAMPLES_PASSED
:
584 case GL_ANY_SAMPLES_PASSED_CONSERVATIVE
:
585 case GL_SAMPLES_PASSED_ARB
:
588 case GL_PRIMITIVES_GENERATED
:
589 case GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN
:
590 case GL_TRANSFORM_FEEDBACK_STREAM_OVERFLOW_ARB
:
591 case GL_TRANSFORM_FEEDBACK_OVERFLOW_ARB
:
592 case GL_VERTICES_SUBMITTED_ARB
:
593 case GL_PRIMITIVES_SUBMITTED_ARB
:
594 case GL_VERTEX_SHADER_INVOCATIONS_ARB
:
595 case GL_GEOMETRY_SHADER_INVOCATIONS
:
596 case GL_GEOMETRY_SHADER_PRIMITIVES_EMITTED_ARB
:
597 case GL_FRAGMENT_SHADER_INVOCATIONS_ARB
:
598 case GL_CLIPPING_INPUT_PRIMITIVES_ARB
:
599 case GL_CLIPPING_OUTPUT_PRIMITIVES_ARB
:
600 case GL_COMPUTE_SHADER_INVOCATIONS_ARB
:
601 case GL_TESS_CONTROL_SHADER_PATCHES_ARB
:
602 case GL_TESS_EVALUATION_SHADER_INVOCATIONS_ARB
:
606 unreachable("Unrecognized query target in is_query_pipelined()");
610 /* Initialize query object functions used on all generations. */
611 void brw_init_common_queryobj_functions(struct dd_function_table
*functions
)
613 functions
->NewQueryObject
= brw_new_query_object
;
614 functions
->DeleteQuery
= brw_delete_query
;
615 functions
->GetTimestamp
= brw_get_timestamp
;
618 /* Initialize Gen4/5-specific query object functions. */
619 void gen4_init_queryobj_functions(struct dd_function_table
*functions
)
621 functions
->BeginQuery
= brw_begin_query
;
622 functions
->EndQuery
= brw_end_query
;
623 functions
->CheckQuery
= brw_check_query
;
624 functions
->WaitQuery
= brw_wait_query
;
625 functions
->QueryCounter
= brw_query_counter
;