3 files changed, 23 insertions, 2 deletions
diff --git a/libs/cputimeinstate/cputimeinstate.cpp b/libs/cputimeinstate/cputimeinstate.cpp
index 462f0db97b..7e9bb7d468 100644
--- a/libs/cputimeinstate/cputimeinstate.cpp
+++ b/libs/cputimeinstate/cputimeinstate.cpp
@@ -155,10 +155,14 @@ static bool initGlobals() {
     return true;
 }
 
-static bool attachTracepointProgram(const std::string &eventType, const std::string &eventName) {
+static int retrieveProgramFd(const std::string &eventType, const std::string &eventName) {
     std::string path = StringPrintf(BPF_FS_PATH "prog_time_in_state_tracepoint_%s_%s",
                                     eventType.c_str(), eventName.c_str());
-    int prog_fd = retrieveProgram(path.c_str());
+    return retrieveProgram(path.c_str());
+}
+
+static bool attachTracepointProgram(const std::string &eventType, const std::string &eventName) {
+    int prog_fd = retrieveProgramFd(eventType, eventName);
     if (prog_fd < 0) return false;
     return bpf_attach_tracepoint(prog_fd, eventType.c_str(), eventName.c_str()) >= 0;
 }
@@ -174,6 +178,17 @@ static std::optional<uint32_t> getPolicyFreqIdx(uint32_t policy) {
     return {};
 }
 
+// Check if tracking is expected to work without activating it.
+bool isTrackingUidTimesSupported() {
+    auto freqs = getCpuFreqs();
+    if (!freqs || freqs->empty()) return false;
+    if (gTracking) return true;
+    if (retrieveProgramFd("sched", "sched_switch") < 0) return false;
+    if (retrieveProgramFd("power", "cpu_frequency") < 0) return false;
+    if (retrieveProgramFd("sched", "sched_process_free") < 0) return false;
+    return true;
+}
+
 // Start tracking and aggregating data to be reported by getUidCpuFreqTimes and getUidsCpuFreqTimes.
 // Returns true on success, false otherwise.
 // Tracking is active only once a live process has successfully called this function; if the calling
diff --git a/libs/cputimeinstate/cputimeinstate.h b/libs/cputimeinstate/cputimeinstate.h
index 46de66936a..41453745a0 100644
--- a/libs/cputimeinstate/cputimeinstate.h
+++ b/libs/cputimeinstate/cputimeinstate.h
@@ -22,6 +22,7 @@
 namespace android {
 namespace bpf {
 
+bool isTrackingUidTimesSupported();
 bool startTrackingUidTimes();
 std::optional<std::vector<std::vector<uint64_t>>> getTotalCpuFreqTimes();
 std::optional<std::vector<std::vector<uint64_t>>> getUidCpuFreqTimes(uint32_t uid);
diff --git a/libs/cputimeinstate/testtimeinstate.cpp b/libs/cputimeinstate/testtimeinstate.cpp
index d25b2e9d6f..2112b10ebc 100644
--- a/libs/cputimeinstate/testtimeinstate.cpp
+++ b/libs/cputimeinstate/testtimeinstate.cpp
@@ -40,6 +40,11 @@ static constexpr uint64_t NSEC_PER_YEAR = NSEC_PER_SEC * 60 * 60 * 24 * 365;
 
 using std::vector;
 
+TEST(TimeInStateTest, IsTrackingSupported) {
+    isTrackingUidTimesSupported();
+    SUCCEED();
+}
+
 TEST(TimeInStateTest, TotalTimeInState) {
     auto times = getTotalCpuFreqTimes();
     ASSERT_TRUE(times.has_value());