Add libbinderdebug
Allows lshal and dumpsys to share the code to get Binder PID info.
Test: atest libbinderdebug_test lshal_test
Test: diff output of lshal before and after this CL
Bug: 140639610
Change-Id: I04dbe2509673502502ac849ef4ae74147404fc43
diff --git a/libs/binderdebug/BinderDebug.cpp b/libs/binderdebug/BinderDebug.cpp
new file mode 100644
index 0000000..b435dba
--- /dev/null
+++ b/libs/binderdebug/BinderDebug.cpp
@@ -0,0 +1,119 @@
+/*
+ * Copyright (C) 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.
+ */
+
+#include <android-base/parseint.h>
+#include <android-base/strings.h>
+#include <binder/Binder.h>
+#include <sys/types.h>
+#include <fstream>
+#include <regex>
+
+#include <binderdebug/BinderDebug.h>
+
+namespace android {
+
+static std::string contextToString(BinderDebugContext context) {
+ switch (context) {
+ case BinderDebugContext::BINDER:
+ return "binder";
+ case BinderDebugContext::HWBINDER:
+ return "hwbinder";
+ case BinderDebugContext::VNDBINDER:
+ return "vndbinder";
+ default:
+ return std::string();
+ }
+}
+
+static status_t scanBinderContext(pid_t pid, const std::string& contextName,
+ std::function<void(const std::string&)> eachLine) {
+ std::ifstream ifs("/dev/binderfs/binder_logs/proc/" + std::to_string(pid));
+ if (!ifs.is_open()) {
+ ifs.open("/d/binder/proc/" + std::to_string(pid));
+ if (!ifs.is_open()) {
+ return -errno;
+ }
+ }
+ static const std::regex kContextLine("^context (\\w+)$");
+
+ bool isDesiredContext = false;
+ std::string line;
+ std::smatch match;
+ while (getline(ifs, line)) {
+ if (std::regex_search(line, match, kContextLine)) {
+ isDesiredContext = match.str(1) == contextName;
+ continue;
+ }
+ if (!isDesiredContext) {
+ continue;
+ }
+ eachLine(line);
+ }
+ return OK;
+}
+
+status_t getBinderPidInfo(BinderDebugContext context, pid_t pid, BinderPidInfo* pidInfo) {
+ std::smatch match;
+ static const std::regex kReferencePrefix("^\\s*node \\d+:\\s+u([0-9a-f]+)\\s+c([0-9a-f]+)\\s+");
+ static const std::regex kThreadPrefix("^\\s*thread \\d+:\\s+l\\s+(\\d)(\\d)");
+ std::string contextStr = contextToString(context);
+ status_t ret = scanBinderContext(pid, contextStr, [&](const std::string& line) {
+ if (std::regex_search(line, match, kReferencePrefix)) {
+ const std::string& ptrString = "0x" + match.str(2); // use number after c
+ uint64_t ptr;
+ if (!::android::base::ParseUint(ptrString.c_str(), &ptr)) {
+ // Should not reach here, but just be tolerant.
+ return;
+ }
+ const std::string proc = " proc ";
+ auto pos = line.rfind(proc);
+ if (pos != std::string::npos) {
+ for (const std::string& pidStr : base::Split(line.substr(pos + proc.size()), " ")) {
+ int32_t pid;
+ if (!::android::base::ParseInt(pidStr, &pid)) {
+ return;
+ }
+ pidInfo->refPids[ptr].push_back(pid);
+ }
+ }
+
+ return;
+ }
+ if (std::regex_search(line, match, kThreadPrefix)) {
+ // "1" is waiting in binder driver
+ // "2" is poll. It's impossible to tell if these are in use.
+ // and HIDL default code doesn't use it.
+ bool isInUse = match.str(1) != "1";
+ // "0" is a thread that has called into binder
+ // "1" is looper thread
+ // "2" is main looper thread
+ bool isBinderThread = match.str(2) != "0";
+ if (!isBinderThread) {
+ return;
+ }
+ if (isInUse) {
+ pidInfo->threadUsage++;
+ }
+
+ pidInfo->threadCount++;
+ return;
+ }
+ return;
+ });
+ return ret;
+}
+
+} // namespace android