GPU Memory: implement libgpumem to interact with bpf
This change implements a libgpumem userspace library which does below:
1. Wait for BpfLoader to get initialized
1. Retrieve the fds from both the bpf program and map
2. Attach the program to the kernel tracepoint and enable the tracepoint
3. Create a BpfMapRO read-only map around the map fd
4. Implement a simple dumpsys interface to grap gpu memory snapshots
Unittests are done and will be added after integration.
Bug: 154524735
Test: atest gpuservice_unittest:GpuMemTest
Change-Id: Idd6d7f83a96551807bf3c1eb56fb53c922d2fee4
Merged-In: Idd6d7f83a96551807bf3c1eb56fb53c922d2fee4
diff --git a/services/gpuservice/gpumem/Android.bp b/services/gpuservice/gpumem/Android.bp
new file mode 100644
index 0000000..b2230b6
--- /dev/null
+++ b/services/gpuservice/gpumem/Android.bp
@@ -0,0 +1,41 @@
+// Copyright 2020 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+cc_library_shared {
+ name: "libgpumem",
+ srcs: [
+ "GpuMem.cpp",
+ ],
+ shared_libs: [
+ "libbase",
+ "libbpf",
+ "libbpf_android",
+ "libcutils",
+ "liblog",
+ "libutils",
+ ],
+ export_include_dirs: ["include"],
+ export_shared_lib_headers: [
+ "libbase",
+ "libbpf_android",
+ ],
+ cppflags: [
+ "-Wall",
+ "-Werror",
+ "-Wformat",
+ "-Wthread-safety",
+ "-Wunused",
+ "-Wunreachable-code",
+ ],
+}
diff --git a/services/gpuservice/gpumem/GpuMem.cpp b/services/gpuservice/gpumem/GpuMem.cpp
new file mode 100644
index 0000000..1d4b524
--- /dev/null
+++ b/services/gpuservice/gpumem/GpuMem.cpp
@@ -0,0 +1,123 @@
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#undef LOG_TAG
+#define LOG_TAG "GpuMem"
+#define ATRACE_TAG ATRACE_TAG_GRAPHICS
+
+#include "gpumem/GpuMem.h"
+
+#include <android-base/stringprintf.h>
+#include <libbpf.h>
+#include <libbpf_android.h>
+#include <log/log.h>
+#include <utils/Trace.h>
+
+#include <unordered_map>
+#include <vector>
+
+namespace android {
+
+using base::StringAppendF;
+
+GpuMem::~GpuMem() {
+ bpf_detach_tracepoint(kGpuMemTraceGroup, kGpuMemTotalTracepoint);
+}
+
+void GpuMem::initialize() {
+ // Make sure bpf programs are loaded
+ bpf::waitForProgsLoaded();
+
+ int fd = bpf::bpfFdGet(kGpuMemTotalProgPath, BPF_F_RDONLY);
+ if (fd < 0) {
+ ALOGE("Failed to retrieve pinned program from %s", kGpuMemTotalProgPath);
+ return;
+ }
+
+ // Attach the program to the tracepoint, and the tracepoint is automatically enabled here.
+ if (bpf_attach_tracepoint(fd, kGpuMemTraceGroup, kGpuMemTotalTracepoint) < 0) {
+ ALOGE("Failed to attach bpf program to %s/%s tracepoint", kGpuMemTraceGroup,
+ kGpuMemTotalTracepoint);
+ return;
+ }
+
+ // Use the read-only wrapper BpfMapRO to properly retrieve the read-only map.
+ auto map = bpf::BpfMapRO<uint64_t, uint64_t>(kGpuMemTotalMapPath);
+ if (!map.isValid()) {
+ ALOGE("Failed to create bpf map from %s", kGpuMemTotalMapPath);
+ return;
+ }
+ setGpuMemTotalMap(map);
+}
+
+void GpuMem::setGpuMemTotalMap(bpf::BpfMap<uint64_t, uint64_t>& map) {
+ mGpuMemTotalMap = std::move(map);
+}
+
+// Dump the snapshots of global and per process memory usage on all gpus
+void GpuMem::dump(const Vector<String16>& /* args */, std::string* result) {
+ ATRACE_CALL();
+
+ if (!mGpuMemTotalMap.isValid()) {
+ result->append("Failed to initialize GPU memory eBPF\n");
+ return;
+ }
+
+ auto res = mGpuMemTotalMap.getFirstKey();
+ if (!res.ok()) {
+ result->append("GPU memory total usage map is empty\n");
+ return;
+ }
+ uint64_t key = res.value();
+ // unordered_map<gpu_id, vector<pair<pid, size>>>
+ std::unordered_map<uint32_t, std::vector<std::pair<uint32_t, uint64_t>>> dumpMap;
+ while (true) {
+ uint32_t gpu_id = key >> 32;
+ uint32_t pid = key;
+
+ res = mGpuMemTotalMap.readValue(key);
+ if (!res.ok()) break;
+ uint64_t size = res.value();
+
+ dumpMap[gpu_id].emplace_back(pid, size);
+
+ res = mGpuMemTotalMap.getNextKey(key);
+ if (!res.ok()) break;
+ key = res.value();
+ }
+
+ for (auto& gpu : dumpMap) {
+ if (gpu.second.empty()) continue;
+ StringAppendF(result, "Memory snapshot for GPU %u:\n", gpu.first);
+
+ std::sort(gpu.second.begin(), gpu.second.end(),
+ [](auto& l, auto& r) { return l.first < r.first; });
+
+ int i = 0;
+ if (gpu.second[0].first != 0) {
+ StringAppendF(result, "Global total: N/A\n");
+ } else {
+ StringAppendF(result, "Global total: %" PRIu64 "\n", gpu.second[0].second);
+ i++;
+ }
+ for (; i < gpu.second.size(); i++) {
+ StringAppendF(result, "Proc %u total: %" PRIu64 "\n", gpu.second[i].first,
+ gpu.second[i].second);
+ }
+ }
+}
+
+} // namespace android
diff --git a/services/gpuservice/gpumem/include/gpumem/GpuMem.h b/services/gpuservice/gpumem/include/gpumem/GpuMem.h
new file mode 100644
index 0000000..6d0322a
--- /dev/null
+++ b/services/gpuservice/gpumem/include/gpumem/GpuMem.h
@@ -0,0 +1,56 @@
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <bpf/BpfMap.h>
+#include <utils/String16.h>
+#include <utils/Vector.h>
+
+namespace android {
+
+class GpuMem {
+public:
+ GpuMem() = default;
+ ~GpuMem();
+
+ // initialize eBPF program and map
+ void initialize();
+ // dumpsys interface
+ void dump(const Vector<String16>& args, std::string* result);
+
+private:
+ // Friend class for testing.
+ friend class TestableGpuMem;
+
+ // set gpu memory total map
+ void setGpuMemTotalMap(bpf::BpfMap<uint64_t, uint64_t>& map);
+
+ // bpf map for GPU memory total data
+ android::bpf::BpfMap<uint64_t, uint64_t> mGpuMemTotalMap;
+
+ // gpu memory tracepoint event category
+ static constexpr char kGpuMemTraceGroup[] = "gpu_mem";
+ // gpu memory total tracepoint
+ static constexpr char kGpuMemTotalTracepoint[] = "gpu_mem_total";
+ // pinned gpu memory total bpf c program path in bpf sysfs
+ static constexpr char kGpuMemTotalProgPath[] =
+ "/sys/fs/bpf/prog_gpu_mem_tracepoint_gpu_mem_gpu_mem_total";
+ // pinned gpu memory total bpf map path in bpf sysfs
+ static constexpr char kGpuMemTotalMapPath[] = "/sys/fs/bpf/map_gpu_mem_gpu_mem_total_map";
+};
+
+} // namespace android