profcollectd: Add binder call to check the supported provider

This allows the forward service to avoid wasting resources if no
provider is available on the device.

Bug: 79161490
Test: build
Change-Id: Ic7cf646e9f8a4390440be824186deb7b2f256c82

6 files changed, 22 insertions, 0 deletions

diff --git a/profcollectd/libprofcollectd/binder_service.cpp b/profcollectd/libprofcollectd/binder_service.cpp
index 92446509..f43f40ee 100644
--- a/profcollectd/libprofcollectd/binder_service.cpp
+++ b/profcollectd/libprofcollectd/binder_service.cpp
@@ -67,5 +67,9 @@ Status ProfcollectdBinder::ProcessProfile() {
   return HandleIfError([=]() { return Scheduler->ProcessProfile(); });
 }
 
+Status ProfcollectdBinder::GetSupportedProvider(std::string* provider) {
+  return HandleIfError([=]() { return Scheduler->GetSupportedProvider(*provider); });
+}
+
 }  // namespace profcollectd
 }  // namespace android
diff --git a/profcollectd/libprofcollectd/binder_service.h b/profcollectd/libprofcollectd/binder_service.h
index af272085..4434427c 100644
--- a/profcollectd/libprofcollectd/binder_service.h
+++ b/profcollectd/libprofcollectd/binder_service.h
@@ -37,6 +37,7 @@ class ProfcollectdBinder : public BinderService<ProfcollectdBinder>,
   binder::Status TerminateCollection() override;
   binder::Status TraceOnce(const std::string& tag) override;
   binder::Status ProcessProfile() override;
+  binder::Status GetSupportedProvider(std::string* provider) override;
 
  protected:
   inline static std::unique_ptr<ProfcollectdScheduler> Scheduler;
diff --git a/profcollectd/libprofcollectd/hwtrace_provider.h b/profcollectd/libprofcollectd/hwtrace_provider.h
index e60a87ff..8e10745f 100644
--- a/profcollectd/libprofcollectd/hwtrace_provider.h
+++ b/profcollectd/libprofcollectd/hwtrace_provider.h
@@ -28,6 +28,11 @@ class HwtraceProvider {
   virtual ~HwtraceProvider() = default;
 
   /**
+   * Get the name of the trace provider.
+   */
+  virtual std::string GetName() = 0;
+
+  /**
    * Trace for the given length of time.
    *
    * @param period Length of time to trace in seconds.
diff --git a/profcollectd/libprofcollectd/scheduler.cpp b/profcollectd/libprofcollectd/scheduler.cpp
index eb47d843..30a181aa 100644
--- a/profcollectd/libprofcollectd/scheduler.cpp
+++ b/profcollectd/libprofcollectd/scheduler.cpp
@@ -185,6 +185,11 @@ OptError ProfcollectdScheduler::ProcessProfile() {
   return std::nullopt;
 }
 
+OptError ProfcollectdScheduler::GetSupportedProvider(std::string& provider) {
+  provider = hwtracer ? hwtracer->GetName() : "";
+  return std::nullopt;
+}
+
 std::ostream& operator<<(std::ostream& os, const ProfcollectdScheduler::Config& config) {
   Json::Value root;
   const auto writer = std::make_unique<Json::StyledStreamWriter>();
diff --git a/profcollectd/libprofcollectd/scheduler.h b/profcollectd/libprofcollectd/scheduler.h
index 31ffc5fb..492b4182 100644
--- a/profcollectd/libprofcollectd/scheduler.h
+++ b/profcollectd/libprofcollectd/scheduler.h
@@ -52,6 +52,7 @@ class ProfcollectdScheduler {
   OptError TerminateCollection();
   OptError TraceOnce(const std::string& tag);
   OptError ProcessProfile();
+  OptError GetSupportedProvider(std::string& provider);
 
  private:
   Config config;
diff --git a/profcollectd/libprofcollectd/simpleperf_etm_provider.cpp b/profcollectd/libprofcollectd/simpleperf_etm_provider.cpp
index 0d6491e6..5e8c55bc 100644
--- a/profcollectd/libprofcollectd/simpleperf_etm_provider.cpp
+++ b/profcollectd/libprofcollectd/simpleperf_etm_provider.cpp
@@ -49,6 +49,7 @@ namespace fs = std::filesystem;
 class SimpleperfETMProvider : public HwtraceProvider {
  public:
   static bool IsSupported();
+  std::string GetName();
   bool Trace(const fs::path& outputPath, const std::string& tag,
              std::chrono::duration<float> samplingPeriod) override;
   bool Process(const fs::path& inputPath, const fs::path& outputPath,
@@ -59,6 +60,11 @@ bool SimpleperfETMProvider::IsSupported() {
   return simpleperf::etm::HasSupport();
 }
 
+std::string SimpleperfETMProvider::GetName() {
+  static constexpr const char* name = "simpleperf_etm";
+  return name;
+}
+
 bool SimpleperfETMProvider::Trace(const fs::path& outputPath, const std::string& tag,
                                   std::chrono::duration<float> samplingPeriod) {
   const std::string timestamp = GetTimestamp();