[Mesa-dev] [PATCH] anv: implement pipeline statistics queries

Ilia Mirkin imirkin at alum.mit.edu
Tue Jan 24 19:48:17 UTC 2017


2-month ping. [ok, it hasn't been 2 months on the dot, but ... close.]

On Tue, Jan 10, 2017 at 5:49 PM, Ilia Mirkin <imirkin at alum.mit.edu> wrote:
> ping.
>
> On Thu, Dec 22, 2016 at 11:14 AM, Ilia Mirkin <imirkin at alum.mit.edu> wrote:
>> Ping? Any further comments/feedback/reviews?
>>
>>
>> On Dec 5, 2016 11:22 AM, "Ilia Mirkin" <imirkin at alum.mit.edu> wrote:
>>
>> On Mon, Dec 5, 2016 at 11:11 AM, Robert Bragg <robert at sixbynine.org> wrote:
>>>
>>>
>>> On Sun, Nov 27, 2016 at 7:23 PM, Ilia Mirkin <imirkin at alum.mit.edu> wrote:
>>>>
>>>> The strategy is to just keep n anv_query_pool_slot entries per query
>>>> instead of one. The available bit is only valid in the last one.
>>>>
>>>> Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
>>>> ---
>>>>
>>>> I think this is in a pretty good state now. I've tested both the direct
>>>> and
>>>> buffer paths with a hacked up cube application, and I'm seeing
>>>> non-ridiculous
>>>> values for the various counters, although I haven't 100% verified them
>>>> for
>>>> accuracy.
>>>>
>>>> This also implements the hsw/bdw workaround for dividing frag invocations
>>>> by 4,
>>>> copied from hsw_queryobj. I tested this on SKL and it seem to divide the
>>>> values
>>>> as expected.
>>>>
>>>> The cube patch I've been testing with is at
>>>> http://paste.debian.net/899374/
>>>> You can flip between copying to a buffer and explicit retrieval by
>>>> commenting
>>>> out the relevant function calls.
>>>>
>>>>  src/intel/vulkan/anv_device.c      |   2 +-
>>>>  src/intel/vulkan/anv_private.h     |   4 +
>>>>  src/intel/vulkan/anv_query.c       |  99 ++++++++++----
>>>>  src/intel/vulkan/genX_cmd_buffer.c | 260
>>>> ++++++++++++++++++++++++++++++++-----
>>>>  4 files changed, 308 insertions(+), 57 deletions(-)
>>>>
>>>>
>>>> diff --git a/src/intel/vulkan/anv_device.c
>>>> b/src/intel/vulkan/anv_device.c
>>>> index 99eb73c..7ad1970 100644
>>>> --- a/src/intel/vulkan/anv_device.c
>>>> +++ b/src/intel/vulkan/anv_device.c
>>>> @@ -427,7 +427,7 @@ void anv_GetPhysicalDeviceFeatures(
>>>>        .textureCompressionASTC_LDR               = pdevice->info.gen >=
>>>> 9,
>>>> /* FINISHME CHV */
>>>>        .textureCompressionBC                     = true,
>>>>        .occlusionQueryPrecise                    = true,
>>>> -      .pipelineStatisticsQuery                  = false,
>>>> +      .pipelineStatisticsQuery                  = true,
>>>>        .fragmentStoresAndAtomics                 = true,
>>>>        .shaderTessellationAndGeometryPointSize   = true,
>>>>        .shaderImageGatherExtended                = false,
>>>> diff --git a/src/intel/vulkan/anv_private.h
>>>> b/src/intel/vulkan/anv_private.h
>>>> index 2fc543d..7271609 100644
>>>> --- a/src/intel/vulkan/anv_private.h
>>>> +++ b/src/intel/vulkan/anv_private.h
>>>> @@ -1763,6 +1763,8 @@ struct anv_render_pass {
>>>>     struct anv_subpass                           subpasses[0];
>>>>  };
>>>>
>>>> +#define ANV_PIPELINE_STATISTICS_COUNT 11
>>>> +
>>>>  struct anv_query_pool_slot {
>>>>     uint64_t begin;
>>>>     uint64_t end;
>>>> @@ -1772,6 +1774,8 @@ struct anv_query_pool_slot {
>>>>  struct anv_query_pool {
>>>>     VkQueryType                                  type;
>>>>     uint32_t                                     slots;
>>>> +   uint32_t                                     pipeline_statistics;
>>>> +   uint32_t                                     slot_stride;
>>>>     struct anv_bo                                bo;
>>>>  };
>>>>
>>>> diff --git a/src/intel/vulkan/anv_query.c b/src/intel/vulkan/anv_query.c
>>>> index 293257b..dc00859 100644
>>>> --- a/src/intel/vulkan/anv_query.c
>>>> +++ b/src/intel/vulkan/anv_query.c
>>>> @@ -38,8 +38,10 @@ VkResult anv_CreateQueryPool(
>>>>     ANV_FROM_HANDLE(anv_device, device, _device);
>>>>     struct anv_query_pool *pool;
>>>>     VkResult result;
>>>> -   uint32_t slot_size;
>>>> -   uint64_t size;
>>>> +   uint32_t slot_size = sizeof(struct anv_query_pool_slot);
>>>> +   uint32_t slot_stride = 1;
>>>> +   uint64_t size = pCreateInfo->queryCount * slot_size;
>>>> +   uint32_t pipeline_statistics = 0;
>>>>
>>>>     assert(pCreateInfo->sType ==
>>>> VK_STRUCTURE_TYPE_QUERY_POOL_CREATE_INFO);
>>>>
>>>> @@ -48,12 +50,16 @@ VkResult anv_CreateQueryPool(
>>>>     case VK_QUERY_TYPE_TIMESTAMP:
>>>>        break;
>>>>     case VK_QUERY_TYPE_PIPELINE_STATISTICS:
>>>> -      return VK_ERROR_INCOMPATIBLE_DRIVER;
>>>> +      pipeline_statistics = pCreateInfo->pipelineStatistics &
>>>> +         ((1 << ANV_PIPELINE_STATISTICS_COUNT) - 1);
>>>> +      slot_stride = _mesa_bitcount(pipeline_statistics);
>>>> +      size *= slot_stride;
>>>> +      break;
>>>>     default:
>>>>        assert(!"Invalid query type");
>>>> +      return VK_ERROR_INCOMPATIBLE_DRIVER;
>>>>     }
>>>>
>>>> -   slot_size = sizeof(struct anv_query_pool_slot);
>>>>     pool = vk_alloc2(&device->alloc, pAllocator, sizeof(*pool), 8,
>>>>                       VK_SYSTEM_ALLOCATION_SCOPE_OBJECT);
>>>>     if (pool == NULL)
>>>> @@ -61,8 +67,9 @@ VkResult anv_CreateQueryPool(
>>>>
>>>>     pool->type = pCreateInfo->queryType;
>>>>     pool->slots = pCreateInfo->queryCount;
>>>> +   pool->pipeline_statistics = pipeline_statistics;
>>>> +   pool->slot_stride = slot_stride;
>>>>
>>>> -   size = pCreateInfo->queryCount * slot_size;
>>>>     result = anv_bo_init_new(&pool->bo, device, size);
>>>>     if (result != VK_SUCCESS)
>>>>        goto fail;
>>>> @@ -95,6 +102,27 @@ void anv_DestroyQueryPool(
>>>>     vk_free2(&device->alloc, pAllocator, pool);
>>>>  }
>>>>
>>>> +static void *
>>>> +store_query_result(void *pData, VkQueryResultFlags flags,
>>>> +                   uint64_t result, uint64_t available)
>>>> +{
>>>> +   if (flags & VK_QUERY_RESULT_64_BIT) {
>>>> +      uint64_t *dst = pData;
>>>> +      *dst++ = result;
>>>> +      if (flags & VK_QUERY_RESULT_WITH_AVAILABILITY_BIT)
>>>> +         *dst++ = available;
>>>> +      return dst;
>>>> +   } else {
>>>> +      uint32_t *dst = pData;
>>>> +      if (result > UINT32_MAX)
>>>> +         result = UINT32_MAX;
>>>> +      *dst++ = result;
>>>> +      if (flags & VK_QUERY_RESULT_WITH_AVAILABILITY_BIT)
>>>> +         *dst++ = available;
>>>> +      return dst;
>>>> +   }
>>>> +}
>>>> +
>>>>  VkResult anv_GetQueryPoolResults(
>>>>      VkDevice                                    _device,
>>>>      VkQueryPool                                 queryPool,
>>>> @@ -112,6 +140,7 @@ VkResult anv_GetQueryPoolResults(
>>>>     int ret;
>>>>
>>>>     assert(pool->type == VK_QUERY_TYPE_OCCLUSION ||
>>>> +          pool->type == VK_QUERY_TYPE_PIPELINE_STATISTICS ||
>>>>            pool->type == VK_QUERY_TYPE_TIMESTAMP);
>>>>
>>>>     if (pData == NULL)
>>>> @@ -129,14 +158,42 @@ VkResult anv_GetQueryPoolResults(
>>>>     void *data_end = pData + dataSize;
>>>>     struct anv_query_pool_slot *slot = pool->bo.map;
>>>>
>>>> -   for (uint32_t i = 0; i < queryCount; i++) {
>>>> +   for (uint32_t i = 0; i < queryCount && pData < data_end;
>>>> +        i++, pData += stride) {
>>>> +      if (pool->type == VK_QUERY_TYPE_PIPELINE_STATISTICS) {
>>>> +         VkQueryResultFlags f = flags &
>>>> ~VK_QUERY_RESULT_WITH_AVAILABILITY_BIT;
>>>> +         void *pos = pData;
>>>> +         uint32_t pipeline_statistics = pool->pipeline_statistics;
>>>> +         struct anv_query_pool_slot *base =
>>>> +            &slot[(firstQuery + i) * pool->slot_stride];
>>>> +
>>>> +         while (pipeline_statistics) {
>>>> +            uint32_t stat = u_bit_scan(&pipeline_statistics);
>>>> +            uint64_t result = base->end - base->begin;
>>>> +
>>>> +            /* WaDividePSInvocationCountBy4:HSW,BDW */
>>>> +            if ((device->info.gen == 8 || device->info.is_haswell) &&
>>>> +                (1 << stat) ==
>>>> VK_QUERY_PIPELINE_STATISTIC_FRAGMENT_SHADER_INVOCATIONS_BIT)
>>>> +               result >>= 2;
>>>> +
>>>> +            pos = store_query_result(pos, f, result, 0);
>>>> +            base++;
>>>> +         }
>>>> +         if (flags & VK_QUERY_RESULT_WITH_AVAILABILITY_BIT) {
>>>> +            base--;
>>>> +            if (flags & VK_QUERY_RESULT_64_BIT)
>>>> +               *(uint64_t *)pos = base->available;
>>>> +            else
>>>> +               *(uint32_t *)pos = base->available;
>>>> +         }
>>>> +         continue;
>>>> +      }
>>>> +
>>>>        switch (pool->type) {
>>>>        case VK_QUERY_TYPE_OCCLUSION: {
>>>>           result = slot[firstQuery + i].end - slot[firstQuery + i].begin;
>>>>           break;
>>>>        }
>>>> -      case VK_QUERY_TYPE_PIPELINE_STATISTICS:
>>>> -         unreachable("pipeline stats not supported");
>>>>        case VK_QUERY_TYPE_TIMESTAMP: {
>>>>           result = slot[firstQuery + i].begin;
>>>>           break;
>>>> @@ -145,23 +202,7 @@ VkResult anv_GetQueryPoolResults(
>>>>           unreachable("invalid pool type");
>>>>        }
>>>>
>>>> -      if (flags & VK_QUERY_RESULT_64_BIT) {
>>>> -         uint64_t *dst = pData;
>>>> -         dst[0] = result;
>>>> -         if (flags & VK_QUERY_RESULT_WITH_AVAILABILITY_BIT)
>>>> -            dst[1] = slot[firstQuery + i].available;
>>>> -      } else {
>>>> -         uint32_t *dst = pData;
>>>> -         if (result > UINT32_MAX)
>>>> -            result = UINT32_MAX;
>>>> -         dst[0] = result;
>>>> -         if (flags & VK_QUERY_RESULT_WITH_AVAILABILITY_BIT)
>>>> -            dst[1] = slot[firstQuery + i].available;
>>>> -      }
>>>> -
>>>> -      pData += stride;
>>>> -      if (pData >= data_end)
>>>> -         break;
>>>> +      store_query_result(pData, flags, result, slot[firstQuery +
>>>> i].available);
>>>>     }
>>>>
>>>>     return VK_SUCCESS;
>>>> @@ -183,6 +224,14 @@ void anv_CmdResetQueryPool(
>>>>           slot[firstQuery + i].available = 0;
>>>>           break;
>>>>        }
>>>> +      case VK_QUERY_TYPE_PIPELINE_STATISTICS: {
>>>> +         struct anv_query_pool_slot *slot = pool->bo.map;
>>>> +
>>>> +         slot = &slot[(firstQuery + i) * pool->slot_stride];
>>>> +         for (uint32_t j = 0; j < pool->slot_stride; j++)
>>>> +            slot[j].available = 0;
>>>> +         break;
>>>> +      }
>>>>        default:
>>>>           assert(!"Invalid query type");
>>>>        }
>>>> diff --git a/src/intel/vulkan/genX_cmd_buffer.c
>>>> b/src/intel/vulkan/genX_cmd_buffer.c
>>>> index a965cd6..1369ac2 100644
>>>> --- a/src/intel/vulkan/genX_cmd_buffer.c
>>>> +++ b/src/intel/vulkan/genX_cmd_buffer.c
>>>> @@ -2272,6 +2272,50 @@ emit_query_availability(struct anv_cmd_buffer
>>>> *cmd_buffer,
>>>>     }
>>>>  }
>>>>
>>>> +#define IA_VERTICES_COUNT               0x2310
>>>> +#define IA_PRIMITIVES_COUNT             0x2318
>>>> +#define VS_INVOCATION_COUNT             0x2320
>>>> +#define HS_INVOCATION_COUNT             0x2300
>>>> +#define DS_INVOCATION_COUNT             0x2308
>>>> +#define GS_INVOCATION_COUNT             0x2328
>>>> +#define GS_PRIMITIVES_COUNT             0x2330
>>>> +#define CL_INVOCATION_COUNT             0x2338
>>>> +#define CL_PRIMITIVES_COUNT             0x2340
>>>> +#define PS_INVOCATION_COUNT             0x2348
>>>> +#define CS_INVOCATION_COUNT             0x2290
>>>> +
>>>> +static const uint32_t PIPELINE_STAT_TO_REG[] = {
>>>> +   IA_VERTICES_COUNT,
>>>> +   IA_PRIMITIVES_COUNT,
>>>> +   VS_INVOCATION_COUNT,
>>>> +   GS_INVOCATION_COUNT,
>>>> +   GS_PRIMITIVES_COUNT,
>>>> +   CL_INVOCATION_COUNT,
>>>> +   CL_PRIMITIVES_COUNT,
>>>> +   PS_INVOCATION_COUNT,
>>>> +   HS_INVOCATION_COUNT,
>>>> +   DS_INVOCATION_COUNT,
>>>> +   CS_INVOCATION_COUNT
>>>> +};
>>>> +
>>>> +static void
>>>> +emit_pipeline_stat(struct anv_cmd_buffer *cmd_buffer, uint32_t stat,
>>>> +                   struct anv_bo *bo, uint32_t offset) {
>>>> +   STATIC_ASSERT(ARRAY_SIZE(PIPELINE_STAT_TO_REG) ==
>>>> +                 ANV_PIPELINE_STATISTICS_COUNT);
>>>> +
>>>> +   uint32_t reg = PIPELINE_STAT_TO_REG[stat];
>>>> +
>>>> +   anv_batch_emit(&cmd_buffer->batch, GENX(MI_STORE_REGISTER_MEM), lrm)
>>>> {
>>>> +      lrm.RegisterAddress  = reg,
>>>> +      lrm.MemoryAddress    = (struct anv_address) { bo, offset };
>>>> +   }
>>>> +   anv_batch_emit(&cmd_buffer->batch, GENX(MI_STORE_REGISTER_MEM), lrm)
>>>> {
>>>> +      lrm.RegisterAddress  = reg + 4,
>>>> +      lrm.MemoryAddress    = (struct anv_address) { bo, offset + 4 };
>>>> +   }
>>>> +}
>>>> +
>>>>  void genX(CmdBeginQuery)(
>>>>      VkCommandBuffer                             commandBuffer,
>>>>      VkQueryPool                                 queryPool,
>>>> @@ -2301,7 +2345,25 @@ void genX(CmdBeginQuery)(
>>>>                            query * sizeof(struct anv_query_pool_slot));
>>>>        break;
>>>>
>>>> -   case VK_QUERY_TYPE_PIPELINE_STATISTICS:
>>>> +   case VK_QUERY_TYPE_PIPELINE_STATISTICS: {
>>>> +      uint32_t pipeline_statistics = pool->pipeline_statistics;
>>>> +      uint32_t slot_offset = query * pool->slot_stride *
>>>> +         sizeof(struct anv_query_pool_slot);
>>>> +
>>>> +      /* TODO: This might only be necessary for certain stats */
>>>> +      anv_batch_emit(&cmd_buffer->batch, GENX(PIPE_CONTROL), pc) {
>>>> +         pc.CommandStreamerStallEnable = true;
>>>> +         pc.StallAtPixelScoreboard = true;
>>>> +      }
>>>
>>>
>>> I couldn't find a reference for needing this for workarounds, though I saw
>>> the workaround Ben implemented for Gen9 + GT4 using a CS stall when
>>> querying
>>> timestamps, which is handled separately.
>>
>> Well, experimentally, I need it for the clipper and frag shader
>> invocation counts to show up - otherwise they're always 0. This is on
>> SKL GT2 with the vk-loader cube patched up as described. Perhaps the
>> timing works out s.t. the counters all update outside of the begin/end
>> "critical section" otherwise, so even though they're moving, the
>> difference remains 0.
>>
>>>
>>> Depending on how strictly we consider that the queries should only measure
>>> the commands they bracket then I think some stalling will be necessary to
>>> serialize the work associated with a query and defer reading the end state
>>> until after the relevant stages have completed their work.
>>>
>>> We aren't very precise about this in GL currently, but in Begin maybe we
>>> should stall until everything >= the statistic-stage is idle and in End
>>> stall until everything <= the statistic-stage is idle before reading
>>> (where
>>> 'statistic-stage' here is the pipeline stage associated with the pipeline
>>> statistic being queried (or respectively the min/max stage for a set)).
>>>
>>> For reference in my implementation of INTEL_performance_query facing this
>>> same question, I'm currently just stalling before and after queries:
>>>
>>>
>>> https://github.com/rib/mesa/blob/wip/rib/oa-next/src/mesa/drivers/dri/i965/brw_performance_query.c#L994
>>>
>>> https://github.com/rib/mesa/blob/wip/rib/oa-next/src/mesa/drivers/dri/i965/brw_performance_query.c#L1136
>>
>> So that's essentially what I'm doing here, I think. (And what the GL
>> driver does.) brw_emit_mi_flush actually emits a lot more flushes than
>> this, but I poked around and the main thing is to have a command
>> streamer stall, which on earlier gens requires at least one other bit
>> set.
>>
>> [Please note that I have no real familiarity with the hardware - I'm
>> mostly just looking at what the GL driver does and copying it here
>> with minor adjustments.]
>>
>>>
>>>> +
>>>> +      while (pipeline_statistics) {
>>>> +         uint32_t stat = u_bit_scan(&pipeline_statistics);
>>>> +
>>>> +         emit_pipeline_stat(cmd_buffer, stat, &pool->bo, slot_offset);
>>>> +         slot_offset += sizeof(struct anv_query_pool_slot);
>>>> +      }
>>>> +      break;
>>>> +   }
>>>>     default:
>>>>        unreachable("");
>>>>     }
>>>> @@ -2314,17 +2376,35 @@ void genX(CmdEndQuery)(
>>>>  {
>>>>     ANV_FROM_HANDLE(anv_cmd_buffer, cmd_buffer, commandBuffer);
>>>>     ANV_FROM_HANDLE(anv_query_pool, pool, queryPool);
>>>> +   uint32_t slot_offset = query * pool->slot_stride *
>>>> +      sizeof(struct anv_query_pool_slot);
>>>>
>>>>     switch (pool->type) {
>>>>     case VK_QUERY_TYPE_OCCLUSION:
>>>> -      emit_ps_depth_count(cmd_buffer, &pool->bo,
>>>> -                          query * sizeof(struct anv_query_pool_slot) +
>>>> 8);
>>>> +      emit_ps_depth_count(cmd_buffer, &pool->bo, slot_offset + 8);
>>>> +      emit_query_availability(cmd_buffer, &pool->bo, slot_offset + 16);
>>>> +      break;
>>>> +
>>>> +   case VK_QUERY_TYPE_PIPELINE_STATISTICS: {
>>>> +      uint32_t pipeline_statistics = pool->pipeline_statistics;
>>>> +      /* TODO: This might only be necessary for certain stats */
>>>> +      anv_batch_emit(&cmd_buffer->batch, GENX(PIPE_CONTROL), pc) {
>>>> +         pc.CommandStreamerStallEnable = true;
>>>> +         pc.StallAtPixelScoreboard = true;
>>>> +      }
>>>> +
>>>> +      while (pipeline_statistics) {
>>>> +         uint32_t stat = u_bit_scan(&pipeline_statistics);
>>>>
>>>> -      emit_query_availability(cmd_buffer, &pool->bo,
>>>> -                              query * sizeof(struct anv_query_pool_slot)
>>>> + 16);
>>>> +         emit_pipeline_stat(cmd_buffer, stat, &pool->bo, slot_offset +
>>>> 8);
>>>> +         slot_offset += sizeof(struct anv_query_pool_slot);
>>>> +      }
>>>> +
>>>> +      slot_offset -= sizeof(struct anv_query_pool_slot);
>>>> +      emit_query_availability(cmd_buffer, &pool->bo, slot_offset + 16);
>>>>        break;
>>>> +   }
>>>>
>>>> -   case VK_QUERY_TYPE_PIPELINE_STATISTICS:
>>>>     default:
>>>>        unreachable("");
>>>>     }
>>>> @@ -2421,6 +2501,31 @@ emit_load_alu_reg_u64(struct anv_batch *batch,
>>>> uint32_t reg,
>>>>  }
>>>>
>>>>  static void
>>>> +emit_load_alu_reg_imm32(struct anv_batch *batch, uint32_t reg, uint32_t
>>>> imm)
>>>> +{
>>>> +   anv_batch_emit(batch, GENX(MI_LOAD_REGISTER_IMM), lri) {
>>>> +      lri.RegisterOffset   = reg;
>>>> +      lri.DataDWord        = imm;
>>>> +   }
>>>> +}
>>>> +
>>>> +static void
>>>> +emit_load_alu_reg_imm64(struct anv_batch *batch, uint32_t reg, uint64_t
>>>> imm)
>>>> +{
>>>> +   emit_load_alu_reg_imm32(batch, reg, (uint32_t)imm);
>>>> +   emit_load_alu_reg_imm32(batch, reg + 4, (uint32_t)(imm >> 32));
>>>> +}
>>>> +
>>>> +static void
>>>> +emit_load_alu_reg_reg32(struct anv_batch *batch, uint32_t src, uint32_t
>>>> dst)
>>>> +{
>>>> +   anv_batch_emit(batch, GENX(MI_LOAD_REGISTER_REG), lrr) {
>>>> +      lrr.SourceRegisterAddress      = src;
>>>> +      lrr.DestinationRegisterAddress = dst;
>>>> +   }
>>>> +}
>>>> +
>>>> +static uint32_t
>>>>  store_query_result(struct anv_batch *batch, uint32_t reg,
>>>>                     struct anv_bo *bo, uint32_t offset,
>>>> VkQueryResultFlags
>>>> flags)
>>>>  {
>>>> @@ -2434,9 +2539,88 @@ store_query_result(struct anv_batch *batch,
>>>> uint32_t reg,
>>>>           srm.RegisterAddress  = reg + 4;
>>>>           srm.MemoryAddress    = (struct anv_address) { bo, offset + 4 };
>>>>        }
>>>> +
>>>> +      return offset + 8;
>>>> +   }
>>>> +
>>>> +   return offset + 4;
>>>> +}
>>>> +
>>>> +/*
>>>> + * GPR0 = GPR0 & ((1ull << n) - 1);
>>>> + */
>>>> +static void
>>>> +keep_gpr0_lower_n_bits(struct anv_batch *batch, uint32_t n)
>>>> +{
>>>> +   assert(n < 64);
>>>> +   emit_load_alu_reg_imm64(batch, CS_GPR(1), (1ull << n) - 1);
>>>> +
>>>> +   uint32_t *dw = anv_batch_emitn(batch, 5, GENX(MI_MATH));
>>>> +   dw[1] = alu(OPCODE_LOAD, OPERAND_SRCA, OPERAND_R0);
>>>> +   dw[2] = alu(OPCODE_LOAD, OPERAND_SRCB, OPERAND_R1);
>>>> +   dw[3] = alu(OPCODE_AND, 0, 0);
>>>> +   dw[4] = alu(OPCODE_STORE, OPERAND_R0, OPERAND_ACCU);
>>>> +}
>>>> +
>>>> +/*
>>>> + * GPR0 = GPR0 << 30;
>>>> + */
>>>> +static void
>>>> +shl_gpr0_by_30_bits(struct anv_batch *batch)
>>>> +{
>>>> +   /* First we mask 34 bits of GPR0 to prevent overflow */
>>>> +   keep_gpr0_lower_n_bits(batch, 34);
>>>> +
>>>> +   const uint32_t outer_count = 5;
>>>> +   const uint32_t inner_count = 6;
>>>> +   STATIC_ASSERT(outer_count * inner_count == 30);
>>>> +   const uint32_t cmd_len = 1 + inner_count * 4;
>>>> +
>>>> +   /* We'll emit 5 commands, each shifting GPR0 left by 6 bits, for a
>>>> total of
>>>> +    * 30 left shifts.
>>>> +    */
>>>> +   for (int o = 0; o < outer_count; o++) {
>>>> +      /* Submit one MI_MATH to shift left by 6 bits */
>>>> +      uint32_t *dw = anv_batch_emitn(batch, cmd_len, GENX(MI_MATH));
>>>> +      dw++;
>>>> +      for (int i = 0; i < inner_count; i++, dw += 4) {
>>>> +         dw[0] = alu(OPCODE_LOAD, OPERAND_SRCA, OPERAND_R0);
>>>> +         dw[1] = alu(OPCODE_LOAD, OPERAND_SRCB, OPERAND_R0);
>>>> +         dw[2] = alu(OPCODE_ADD, 0, 0);
>>>> +         dw[3] = alu(OPCODE_STORE, OPERAND_R0, OPERAND_ACCU);
>>>> +      }
>>>>     }
>>>>  }
>>>>
>>>> +/*
>>>> + * GPR0 = GPR0 >> 2;
>>>> + *
>>>> + * Note that the upper 30 bits of GPR are lost!
>>>> + */
>>>> +static void
>>>> +shr_gpr0_by_2_bits(struct anv_batch *batch)
>>>> +{
>>>> +   shl_gpr0_by_30_bits(batch);
>>>> +   emit_load_alu_reg_reg32(batch, CS_GPR(0) + 4, CS_GPR(0));
>>>> +   emit_load_alu_reg_imm32(batch, CS_GPR(0) + 4, 0);
>>>> +}
>>>> +
>>>> +static void
>>>> +compute_query_result(struct anv_batch *batch, struct anv_bo *bo,
>>>> +                     uint32_t dst_reg, uint32_t offset)
>>>> +{
>>>> +   emit_load_alu_reg_u64(batch, CS_GPR(0), bo, offset);
>>>> +   emit_load_alu_reg_u64(batch, CS_GPR(1), bo, offset + 8);
>>>> +
>>>> +   /* FIXME: We need to clamp the result for 32 bit. */
>>>> +
>>>> +   uint32_t *dw = anv_batch_emitn(batch, 5, GENX(MI_MATH));
>>>> +   dw[1] = alu(OPCODE_LOAD, OPERAND_SRCA, OPERAND_R1);
>>>> +   dw[2] = alu(OPCODE_LOAD, OPERAND_SRCB, OPERAND_R0);
>>>> +   dw[3] = alu(OPCODE_SUB, 0, 0);
>>>> +   dw[4] = alu(OPCODE_STORE, dst_reg, OPERAND_ACCU);
>>>> +}
>>>> +
>>>>  void genX(CmdCopyQueryPoolResults)(
>>>>      VkCommandBuffer                             commandBuffer,
>>>>      VkQueryPool                                 queryPool,
>>>> @@ -2459,50 +2643,64 @@ void genX(CmdCopyQueryPoolResults)(
>>>>        }
>>>>     }
>>>>
>>>> -   dst_offset = buffer->offset + destOffset;
>>>>     for (uint32_t i = 0; i < queryCount; i++) {
>>>> -
>>>> +      dst_offset = buffer->offset + destOffset + destStride * i;
>>>>        slot_offset = (firstQuery + i) * sizeof(struct
>>>> anv_query_pool_slot);
>>>>        switch (pool->type) {
>>>>        case VK_QUERY_TYPE_OCCLUSION:
>>>> -         emit_load_alu_reg_u64(&cmd_buffer->batch,
>>>> -                               CS_GPR(0), &pool->bo, slot_offset);
>>>> -         emit_load_alu_reg_u64(&cmd_buffer->batch,
>>>> -                               CS_GPR(1), &pool->bo, slot_offset + 8);
>>>> -
>>>> -         /* FIXME: We need to clamp the result for 32 bit. */
>>>> -
>>>> -         uint32_t *dw = anv_batch_emitn(&cmd_buffer->batch, 5,
>>>> GENX(MI_MATH));
>>>> -         dw[1] = alu(OPCODE_LOAD, OPERAND_SRCA, OPERAND_R1);
>>>> -         dw[2] = alu(OPCODE_LOAD, OPERAND_SRCB, OPERAND_R0);
>>>> -         dw[3] = alu(OPCODE_SUB, 0, 0);
>>>> -         dw[4] = alu(OPCODE_STORE, OPERAND_R2, OPERAND_ACCU);
>>>> +         compute_query_result(&cmd_buffer->batch, &pool->bo, OPERAND_R2,
>>>> +                              slot_offset);
>>>> +         dst_offset = store_query_result(
>>>> +               &cmd_buffer->batch,
>>>> +               CS_GPR(2), buffer->bo, dst_offset, flags);
>>>>           break;
>>>>
>>>>        case VK_QUERY_TYPE_TIMESTAMP:
>>>>           emit_load_alu_reg_u64(&cmd_buffer->batch,
>>>>                                 CS_GPR(2), &pool->bo, slot_offset);
>>>> +         dst_offset = store_query_result(
>>>> +               &cmd_buffer->batch,
>>>> +               CS_GPR(2), buffer->bo, dst_offset, flags);
>>>>           break;
>>>>
>>>> +      case VK_QUERY_TYPE_PIPELINE_STATISTICS: {
>>>> +         uint32_t pipeline_statistics = pool->pipeline_statistics;
>>>> +
>>>> +         slot_offset *= pool->slot_stride;
>>>> +         while (pipeline_statistics) {
>>>> +            uint32_t stat = u_bit_scan(&pipeline_statistics);
>>>> +
>>>> +            compute_query_result(&cmd_buffer->batch, &pool->bo,
>>>> OPERAND_R0,
>>>> +                                 slot_offset);
>>>> +
>>>> +            /* WaDividePSInvocationCountBy4:HSW,BDW */
>>>> +            if ((cmd_buffer->device->info.gen == 8 ||
>>>> +                 cmd_buffer->device->info.is_haswell) &&
>>>> +                (1 << stat) ==
>>>> VK_QUERY_PIPELINE_STATISTIC_FRAGMENT_SHADER_INVOCATIONS_BIT) {
>>>> +               shr_gpr0_by_2_bits(&cmd_buffer->batch);
>>>> +            }
>>>> +            dst_offset = store_query_result(
>>>> +                  &cmd_buffer->batch,
>>>> +                  CS_GPR(0), buffer->bo, dst_offset, flags);
>>>> +            slot_offset += sizeof(struct anv_query_pool_slot);
>>>> +         }
>>>> +
>>>> +         /* Get the slot offset to where it's supposed to be for the
>>>> +          * availability bit.
>>>> +          */
>>>> +         slot_offset -= sizeof(struct anv_query_pool_slot);
>>>> +         break;
>>>> +      }
>>>>        default:
>>>>           unreachable("unhandled query type");
>>>>        }
>>>>
>>>> -      store_query_result(&cmd_buffer->batch,
>>>> -                         CS_GPR(2), buffer->bo, dst_offset, flags);
>>>> -
>>>>        if (flags & VK_QUERY_RESULT_WITH_AVAILABILITY_BIT) {
>>>>           emit_load_alu_reg_u64(&cmd_buffer->batch, CS_GPR(0),
>>>>                                 &pool->bo, slot_offset + 16);
>>>> -         if (flags & VK_QUERY_RESULT_64_BIT)
>>>> -            store_query_result(&cmd_buffer->batch,
>>>> -                               CS_GPR(0), buffer->bo, dst_offset + 8,
>>>> flags);
>>>> -         else
>>>> -            store_query_result(&cmd_buffer->batch,
>>>> -                               CS_GPR(0), buffer->bo, dst_offset + 4,
>>>> flags);
>>>> +         store_query_result(&cmd_buffer->batch,
>>>> +                            CS_GPR(0), buffer->bo, dst_offset, flags);
>>>>        }
>>>> -
>>>> -      dst_offset += destStride;
>>>>     }
>>>>  }
>>>
>>>
>>> I was a bit surprised to see us needing to go the same route as GL query
>>> objects with using the command streamer's very limited ALU for fixing up
>>> metrics on the gpu instead of doing that on the CPU if possible.
>>>
>>> My understanding had been that multiple HW vendors pushed back on the
>>> design
>>> of these query apis to ensure they could deal with counter scaling and
>>> normalization on the CPU without needing to support direct feedback into
>>> the
>>> gpu. Reading the spec though it does unfortunately look like
>>> vkCmdCopyQueryPoolResults implies scaling on the gpu :-/
>>
>> Yeah, that looks identical to ARB_query_buffer_object functionality,
>> with very minor differences.
>>
>>>
>>> One thorny problem we have today at least with GL is that we don't scale
>>> Skylake timestamps properly when using the ALU considering the extra
>>> annoyance of scaling by a floating point factor of 83.3333. In the future
>>> this scale factor might ideally not even be a constant if we can take
>>> advantage of training done in the kernel to determine a more accurate
>>> frequency (ref:
>>> https://lists.freedesktop.org/archives/intel-gfx/2016-June/097272.html)
>>> Also
>>> for reference here, there's this patch that looks at fixing the timestamp
>>> scaling done on the cpu for SKL:
>>> https://patchwork.freedesktop.org/patch/118855/ I understand you aren't
>>> dealing with timestamp scaling here, but it seems like an a example of
>>> where
>>> it's getting a bit out-of-hand using the ALU for this type of purpose.
>>
>> I haven't checked, but I hope that the timestamp units can be in
>> whatever you want. So you can hopefully get away without scaling.
>>
>>>
>>> Can we maybe at least consider the complexity trade-off from using a
>>> shader
>>> instead of ALU - or consider if there's a legitimate way we're missing of
>>> using the cpu here (though I suppose not).
>>
>> Go ahead :) I was just copying the GL approach. Happy to rip out the
>> MI_MATH stuff and make the feature IVB + SKL+ only for now if you all
>> agree that the MI_MATH stuff is bad. IMHO the complexity of the
>> MI_MATH logic is quite small for the / 4 case, but I don't feel like
>> I'm particularly part of the decision committee.
>>
>> Cheers,
>>
>>   -ilia
>>
>>


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