1 //
2 // Copyright 2016 Pixar
3 //
4 // Licensed under the Apache License, Version 2.0 (the "Apache License")
5 // with the following modification; you may not use this file except in
6 // compliance with the Apache License and the following modification to it:
7 // Section 6. Trademarks. is deleted and replaced with:
8 //
9 // 6. Trademarks. This License does not grant permission to use the trade
10 // names, trademarks, service marks, or product names of the Licensor
11 // and its affiliates, except as required to comply with Section 4(c) of
12 // the License and to reproduce the content of the NOTICE file.
13 //
14 // You may obtain a copy of the Apache License at
15 //
16 // http://www.apache.org/licenses/LICENSE-2.0
17 //
18 // Unless required by applicable law or agreed to in writing, software
19 // distributed under the Apache License with the above modification is
20 // distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
21 // KIND, either express or implied. See the Apache License for the specific
22 // language governing permissions and limitations under the Apache License.
23 //
24
25 #include "pxr/pxr.h"
26 #include "pxr/usd/pcp/layerPrefetchRequest.h"
27 #include "pxr/usd/pcp/layerStackRegistry.h"
28 #include "pxr/base/work/dispatcher.h"
29 #include "pxr/base/work/threadLimits.h"
30 #include "pxr/base/work/withScopedParallelism.h"
31
32 #include <tbb/spin_mutex.h>
33
34 PXR_NAMESPACE_OPEN_SCOPE
35
36 namespace {
37
38 struct _Opener
39 {
_Opener__anon04aea4390111::_Opener40 explicit _Opener(const Pcp_MutedLayers& mutedLayers,
41 std::set<SdfLayerRefPtr> *retainedLayers)
42 : _mutedLayers(mutedLayers)
43 , _retainedLayers(retainedLayers) {}
44
~_Opener__anon04aea4390111::_Opener45 ~_Opener() { _dispatcher.Wait(); }
46
OpenSublayers__anon04aea4390111::_Opener47 void OpenSublayers(const SdfLayerRefPtr &layer,
48 const SdfLayer::FileFormatArguments &layerArgs) {
49 TF_FOR_ALL(path, layer->GetSubLayerPaths()) {
50 _dispatcher.Run(
51 &_Opener::_OpenSublayer, this, *path, layer, layerArgs);
52 }
53 }
54
55 private:
_OpenSublayer__anon04aea4390111::_Opener56 void _OpenSublayer(std::string path,
57 const SdfLayerRefPtr &anchorLayer,
58 const SdfLayer::FileFormatArguments &layerArgs) {
59 if (_mutedLayers.IsLayerMuted(anchorLayer, path)) {
60 return;
61 }
62
63 // Open this specific sublayer path.
64 // The call to SdfLayer::FindOrOpenRelativeToLayer() may take some
65 // time, potentially multiple seconds.
66 if (SdfLayerRefPtr sublayer =
67 SdfLayer::FindOrOpenRelativeToLayer(anchorLayer, path, layerArgs)) {
68 // Retain this sublayer.
69 bool didInsert;
70 {
71 tbb::spin_mutex::scoped_lock lock(_retainedLayersMutex);
72 didInsert = _retainedLayers->insert(sublayer).second;
73 }
74 // Open the nested sublayers. Only do this if we haven't seen this
75 // layer before, i.e. didInsert is true.
76 if (didInsert)
77 OpenSublayers(sublayer, layerArgs);
78 }
79 }
80
81 WorkDispatcher _dispatcher;
82 const Pcp_MutedLayers& _mutedLayers;
83 std::set<SdfLayerRefPtr> *_retainedLayers;
84 mutable tbb::spin_mutex _retainedLayersMutex;
85 };
86
87 } // anon
88
89 void
RequestSublayerStack(const SdfLayerRefPtr & layer,const SdfLayer::FileFormatArguments & args)90 PcpLayerPrefetchRequest::RequestSublayerStack(
91 const SdfLayerRefPtr &layer,
92 const SdfLayer::FileFormatArguments &args)
93 {
94 _sublayerRequests.insert(std::make_pair(layer, args));
95 }
96
97 void
Run(const Pcp_MutedLayers & mutedLayers)98 PcpLayerPrefetchRequest::Run(const Pcp_MutedLayers& mutedLayers)
99 {
100 if (!WorkHasConcurrency()) {
101 // Do not bother pre-fetching if we do not have extra threads
102 // available.
103 return;
104 }
105
106 // Release the GIL so we don't deadlock when Sd tries to get a path
107 // resolver (which does ref-counting on the resolver, which requires
108 // the GIL to manage TfRefBase identity-uniqueness).
109 TF_PY_ALLOW_THREADS_IN_SCOPE();
110
111 std::set<_Request> requests;
112 requests.swap(_sublayerRequests);
113
114 // Open all the sublayers in the request.
115 WorkWithScopedParallelism([&]() {
116 _Opener opener(mutedLayers, &_retainedLayers);
117 TF_FOR_ALL(req, requests)
118 opener.OpenSublayers(req->first, req->second);
119 });
120 }
121
122 PXR_NAMESPACE_CLOSE_SCOPE
123