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

Ilia Mirkin imirkin at alum.mit.edu
Tue Feb 21 20:32:29 UTC 2017


Looks like after nearly 3 months of no reviews that lead to R-b's[1],
this patch no longer applies to master. I'm abandoning it. If anyone's
interested, feel free to pick it up and make it your own.

Cheers,

  -ilia

[1] Robert did look at it, but didn't have significant feedback or say
what I needed to do to get a R-b, nor is he one of the main anv
contributors, so I'd have to get someone else's anyways.


On Tue, Jan 24, 2017 at 2:48 PM, Ilia Mirkin <imirkin at alum.mit.edu> wrote:
> 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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