Occlusion query fixes from PR review.
MVKOcclusionQueryCommandEncoderState::beginOcclusionQuery() check for visibility
buffer exhaustion, and if needed, log an error and disable further visibility
tracking for the remainder of the current MTLCommandBuffer.
Create visibility buffer if needed during MVKCommandEncoder::beginMetalRenderPass.
Simplify MVKCommandEncodingContext to PODS.
diff --git a/MoltenVK/MoltenVK/Commands/MVKCommandBuffer.h b/MoltenVK/MoltenVK/Commands/MVKCommandBuffer.h
index fa3bb7f..7d9c92f 100644
--- a/MoltenVK/MoltenVK/Commands/MVKCommandBuffer.h
+++ b/MoltenVK/MoltenVK/Commands/MVKCommandBuffer.h
@@ -52,13 +52,7 @@
/** Context for tracking information across multiple encodings. */
typedef struct MVKCommandEncodingContext {
NSUInteger mtlVisibilityResultOffset = 0;
-
- void incrementMTLVisibilityResultOffset(MVKCommandEncoder* cmdEncoder);
- const MVKMTLBufferAllocation* getVisibilityResultBuffer(MVKCommandEncoder* cmdEncoder);
-
-private:
- const MVKMTLBufferAllocation* _visibilityResultBuffer = nullptr;
-
+ const MVKMTLBufferAllocation* visibilityResultBuffer = nullptr;
} MVKCommandEncodingContext;
diff --git a/MoltenVK/MoltenVK/Commands/MVKCommandBuffer.mm b/MoltenVK/MoltenVK/Commands/MVKCommandBuffer.mm
index 7225d93..18d2441 100644
--- a/MoltenVK/MoltenVK/Commands/MVKCommandBuffer.mm
+++ b/MoltenVK/MoltenVK/Commands/MVKCommandBuffer.mm
@@ -350,7 +350,10 @@
_isRenderingEntireAttachment,
loadOverride);
if (_cmdBuffer->_needsVisibilityResultMTLBuffer) {
- mtlRPDesc.visibilityResultBuffer = _pEncodingContext->getVisibilityResultBuffer(this)->_mtlBuffer;
+ if ( !_pEncodingContext->visibilityResultBuffer ) {
+ _pEncodingContext->visibilityResultBuffer = getTempMTLBuffer(_pDeviceMetalFeatures->maxQueryBufferSize, true, true);
+ }
+ mtlRPDesc.visibilityResultBuffer = _pEncodingContext->visibilityResultBuffer->_mtlBuffer;
}
VkExtent2D fbExtent = _framebufferExtent;
@@ -804,32 +807,6 @@
#pragma mark -
-#pragma mark MVKCommandEncodingContext
-
-// Increment to the next query slot offset. If we reach the size of the visibility buffer,
-// reset to retrieve and start filling another visibility buffer. This approach may still
-// cause Metal validation errors if the platform does not permit offsets to be reused
-// witin a MTLCommandBuffer, even when a different visibility buffer is used.
-// We don't test against the size of the visibility buffer itself, because this call may
-// arrive before the visibiltiy buffer in the case of a query that ends before the renderpass.
-void MVKCommandEncodingContext::incrementMTLVisibilityResultOffset(MVKCommandEncoder* cmdEncoder) {
- mtlVisibilityResultOffset += kMVKQuerySlotSizeInBytes;
-
- if (mtlVisibilityResultOffset + kMVKQuerySlotSizeInBytes > cmdEncoder->_pDeviceMetalFeatures->maxQueryBufferSize) {
- _visibilityResultBuffer = nullptr;
- mtlVisibilityResultOffset = 0;
- }
-}
-
-const MVKMTLBufferAllocation* MVKCommandEncodingContext::getVisibilityResultBuffer(MVKCommandEncoder* cmdEncoder) {
- if ( !_visibilityResultBuffer ) {
- _visibilityResultBuffer = cmdEncoder->getTempMTLBuffer(cmdEncoder->_pDeviceMetalFeatures->maxQueryBufferSize, true, true);
- }
- return _visibilityResultBuffer;
-}
-
-
-#pragma mark -
#pragma mark Support functions
NSString* mvkMTLCommandBufferLabel(MVKCommandUse cmdUse) {
diff --git a/MoltenVK/MoltenVK/Commands/MVKCommandEncoderState.mm b/MoltenVK/MoltenVK/Commands/MVKCommandEncoderState.mm
index 2f9312b..8093cab 100644
--- a/MoltenVK/MoltenVK/Commands/MVKCommandEncoderState.mm
+++ b/MoltenVK/MoltenVK/Commands/MVKCommandEncoderState.mm
@@ -1073,10 +1073,9 @@
#pragma mark MVKOcclusionQueryCommandEncoderState
void MVKOcclusionQueryCommandEncoderState::endMetalRenderPass() {
+ const MVKMTLBufferAllocation* vizBuff = _cmdEncoder->_pEncodingContext->visibilityResultBuffer;
+ if ( !vizBuff || _mtlRenderPassQueries.empty() ) { return; } // Nothing to do.
- if (_mtlRenderPassQueries.empty()) { return; } // Nothing to do.
-
- const MVKMTLBufferAllocation* vizResultBuffer = _cmdEncoder->_pEncodingContext->getVisibilityResultBuffer(_cmdEncoder);
id<MTLComputePipelineState> mtlAccumState = _cmdEncoder->getCommandEncodingPool()->getAccumulateOcclusionQueryResultsMTLComputePipelineState();
id<MTLComputeCommandEncoder> mtlAccumEncoder = _cmdEncoder->getMTLComputeEncoder(kMVKCommandUseAccumOcclusionQuery);
[mtlAccumEncoder setComputePipelineState: mtlAccumState];
@@ -1085,8 +1084,8 @@
[mtlAccumEncoder setBuffer: qryLoc.queryPool->getVisibilityResultMTLBuffer()
offset: qryLoc.queryPool->getVisibilityResultOffset(qryLoc.query)
atIndex: 0];
- [mtlAccumEncoder setBuffer: vizResultBuffer->_mtlBuffer
- offset: vizResultBuffer->_offset + qryLoc.visibilityBufferOffset
+ [mtlAccumEncoder setBuffer: vizBuff->_mtlBuffer
+ offset: vizBuff->_offset + qryLoc.visibilityBufferOffset
atIndex: 1];
[mtlAccumEncoder dispatchThreadgroups: MTLSizeMake(1, 1, 1)
threadsPerThreadgroup: MTLSizeMake(1, 1, 1)];
@@ -1095,16 +1094,28 @@
_mtlRenderPassQueries.clear();
}
+// The Metal visibility buffer has a finite size, and on some Metal platforms (looking at you M1),
+// query offsets cannnot be reused with the same MTLCommandBuffer. If enough occlusion queries are
+// begun within a single MTLCommandBuffer, it may exhaust the visibility buffer. If that occurs,
+// report an error and disable further visibility tracking for the remainder of the MTLCommandBuffer.
+// In most cases, a MTLCommandBuffer corresponds to a Vulkan command submit (VkSubmitInfo),
+// and so the error text is framed in terms of the Vulkan submit.
void MVKOcclusionQueryCommandEncoderState::beginOcclusionQuery(MVKOcclusionQueryPool* pQueryPool, uint32_t query, VkQueryControlFlags flags) {
- bool shouldCount = _cmdEncoder->_pDeviceFeatures->occlusionQueryPrecise && mvkAreAllFlagsEnabled(flags, VK_QUERY_CONTROL_PRECISE_BIT);
- _mtlVisibilityResultMode = shouldCount ? MTLVisibilityResultModeCounting : MTLVisibilityResultModeBoolean;
- _mtlRenderPassQueries.emplace_back(pQueryPool, query, _cmdEncoder->_pEncodingContext->mtlVisibilityResultOffset);
+ if (_cmdEncoder->_pEncodingContext->mtlVisibilityResultOffset + kMVKQuerySlotSizeInBytes <= _cmdEncoder->_pDeviceMetalFeatures->maxQueryBufferSize) {
+ bool shouldCount = _cmdEncoder->_pDeviceFeatures->occlusionQueryPrecise && mvkAreAllFlagsEnabled(flags, VK_QUERY_CONTROL_PRECISE_BIT);
+ _mtlVisibilityResultMode = shouldCount ? MTLVisibilityResultModeCounting : MTLVisibilityResultModeBoolean;
+ _mtlRenderPassQueries.emplace_back(pQueryPool, query, _cmdEncoder->_pEncodingContext->mtlVisibilityResultOffset);
+ } else {
+ reportError(VK_ERROR_OUT_OF_DEVICE_MEMORY, "vkCmdBeginQuery(): The maximum number of queries in a single Vulkan command submission is %llu.", _cmdEncoder->_pDeviceMetalFeatures->maxQueryBufferSize / kMVKQuerySlotSizeInBytes);
+ _mtlVisibilityResultMode = MTLVisibilityResultModeDisabled;
+ _cmdEncoder->_pEncodingContext->mtlVisibilityResultOffset -= kMVKQuerySlotSizeInBytes;
+ }
markDirty();
}
void MVKOcclusionQueryCommandEncoderState::endOcclusionQuery(MVKOcclusionQueryPool* pQueryPool, uint32_t query) {
_mtlVisibilityResultMode = MTLVisibilityResultModeDisabled;
- _cmdEncoder->_pEncodingContext->incrementMTLVisibilityResultOffset(_cmdEncoder);
+ _cmdEncoder->_pEncodingContext->mtlVisibilityResultOffset += kMVKQuerySlotSizeInBytes;
markDirty();
}
