simpleperf: suppress read symbol warning for not-ELF files.

Bug: 195561085
Test: run simpleperf_unit_test
Change-Id: I79ea304a9c7743a18e69548598167aec7577272f

2 files changed, 51 insertions, 2 deletions

diff --git a/simpleperf/dso.cpp b/simpleperf/dso.cpp
index 7167c02d..71d40c38 100644
--- a/simpleperf/dso.cpp
+++ b/simpleperf/dso.cpp
@@ -617,8 +617,17 @@ class ElfDso : public Dso {
     if (elf) {
       status = elf->ParseSymbols(symbol_callback);
     }
-    ReportReadElfSymbolResult(status, path_, GetDebugFilePath(),
-                              symbols_.empty() ? android::base::WARNING : android::base::DEBUG);
+    android::base::LogSeverity log_level = android::base::WARNING;
+    if (!symbols_.empty()) {
+      // We already have some symbols when recording.
+      log_level = android::base::DEBUG;
+    }
+    if ((status == ElfStatus::FILE_NOT_FOUND || status == ElfStatus::FILE_MALFORMED) &&
+        build_id.IsEmpty()) {
+      // This is likely to be a file wongly thought of as an ELF file, maybe due to stack unwinding.
+      log_level = android::base::DEBUG;
+    }
+    ReportReadElfSymbolResult(status, path_, GetDebugFilePath(), log_level);
     SortAndFixSymbols(symbols);
     return symbols;
   }
diff --git a/simpleperf/dso_test.cpp b/simpleperf/dso_test.cpp
index d8ab3f8b..a1a37d34 100644
--- a/simpleperf/dso_test.cpp
+++ b/simpleperf/dso_test.cpp
@@ -331,3 +331,43 @@ TEST(dso, search_debug_file_only_when_needed) {
   ASSERT_NE(capture.str().find("build id mismatch"), std::string::npos);
   capture.Stop();
 }
+
+TEST(dso, read_symbol_warning) {
+  {
+    // Don't warn when the file may not be an ELF file.
+    auto dso = Dso::CreateDso(DSO_ELF_FILE, GetTestData("not_exist_file"));
+    CapturedStderr capture;
+    dso->LoadSymbols();
+    ASSERT_EQ(capture.str().find("failed to read symbols"), std::string::npos);
+  }
+  {
+    // Don't warn when the file may not be an ELF file.
+    auto dso = Dso::CreateDso(DSO_ELF_FILE, GetTestData("base.vdex"));
+    CapturedStderr capture;
+    dso->LoadSymbols();
+    ASSERT_EQ(capture.str().find("failed to read symbols"), std::string::npos);
+  }
+  {
+    // Warn when the file is an ELF file (having a build id).
+    std::string file_path = GetTestData("not_exist_file");
+    Dso::SetBuildIds(
+        {std::make_pair(file_path, BuildId("1b12a384a9f4a3f3659b7171ca615dbec3a81f71"))});
+    auto dso = Dso::CreateDso(DSO_ELF_FILE, file_path);
+    CapturedStderr capture;
+    dso->LoadSymbols();
+    ASSERT_NE(capture.str().find("failed to read symbols"), std::string::npos);
+  }
+  {
+    // Don't warn when we already have symbols.
+    std::string file_path = GetTestData("not_exist_file");
+    Dso::SetBuildIds(
+        {std::make_pair(file_path, BuildId("1b12a384a9f4a3f3659b7171ca615dbec3a81f71"))});
+    auto dso = Dso::CreateDso(DSO_ELF_FILE, file_path);
+    std::vector<Symbol> symbols;
+    symbols.emplace_back("fake_symbol", 0x1234, 0x60);
+    dso->SetSymbols(&symbols);
+    CapturedStderr capture;
+    dso->LoadSymbols();
+    ASSERT_EQ(capture.str().find("failed to read symbols"), std::string::npos);
+  }
+}