SERVER-47892 DiagnosticInfo should use Client to acquire timestamps

3 files changed, 22 insertions, 12 deletions

diff --git a/src/mongo/util/diagnostic_info.cpp b/src/mongo/util/diagnostic_info.cpp
index 22e7287ae9b..49076e76c91 100644
--- a/src/mongo/util/diagnostic_info.cpp
+++ b/src/mongo/util/diagnostic_info.cpp
@@ -187,9 +187,7 @@ MONGO_INITIALIZER_GENERAL(DiagnosticInfo, (/* NO PREREQS */), ("FinalizeDiagnost
     class DiagnosticListener : public latch_detail::DiagnosticListener {
         void onContendedLock(const Identity& id) override {
             if (auto client = Client::getCurrent()) {
-                auto& handle = getDiagnosticInfoHandle(client);
-                stdx::lock_guard<stdx::mutex> lk(handle.mutex);
-                handle.list.emplace_front(DiagnosticInfo::capture(id.name()));
+                DiagnosticInfo::capture(client, id.name());
 
                 if (currentOpSpawnsThreadWaitingForLatch.shouldFail() &&
                     (id.name() == kBlockedOpMutexName)) {
@@ -229,9 +227,7 @@ MONGO_INITIALIZER(InterruptibleWaitListener)(InitializerContext* context) {
 
         void addInfo(const StringData& name) {
             if (auto client = Client::getCurrent()) {
-                auto& handle = getDiagnosticInfoHandle(client);
-                stdx::lock_guard<stdx::mutex> lk(handle.mutex);
-                handle.list.emplace_front(DiagnosticInfo::capture(name));
+                DiagnosticInfo::capture(client, name);
 
                 if (currentOpSpawnsThreadWaitingForLatch.shouldFail() &&
                     (name == kBlockedOpInterruptibleName)) {
@@ -278,13 +274,23 @@ std::string DiagnosticInfo::toString() const {
         _captureName.toString(), _timestamp.toString(), _backtrace.data.size());
 }
 
-DiagnosticInfo DiagnosticInfo::capture(const StringData& captureName, Options options) {
+const DiagnosticInfo& DiagnosticInfo::capture(Client* client,
+                                              const StringData& captureName,
+                                              Options options) noexcept {
+    auto currentTime = client->getServiceContext()->getFastClockSource()->now();
+
     // Since we don't have a fast enough backtrace implementation at the moment, the Backtrace is
     // always empty. If SERVER-44091 happens, this should branch on options.shouldTakeBacktrace
     auto backtrace = Backtrace{};
-    auto currentTime = getGlobalServiceContext()->getFastClockSource()->now();
 
-    return DiagnosticInfo(currentTime, captureName, std::move(backtrace));
+    auto info = DiagnosticInfo(currentTime, captureName, std::move(backtrace));
+
+    auto& handle = getDiagnosticInfoHandle(client);
+
+    stdx::lock_guard<stdx::mutex> lk(handle.mutex);
+    handle.list.emplace_front(std::move(info));
+
+    return handle.list.front();
 }
 
 DiagnosticInfo::BlockedOpGuard::~BlockedOpGuard() {
diff --git a/src/mongo/util/diagnostic_info.h b/src/mongo/util/diagnostic_info.h
index 2b457fc50fe..dc6b3fbde2c 100644
--- a/src/mongo/util/diagnostic_info.h
+++ b/src/mongo/util/diagnostic_info.h
@@ -85,7 +85,9 @@ public:
     /**
      * Captures the diagnostic information based on the caller's context.
      */
-    static DiagnosticInfo capture(const StringData& captureName, Options options = Options{});
+    static const DiagnosticInfo& capture(Client* client,
+                                         const StringData& captureName,
+                                         Options options = Options{}) noexcept;
 
     /**
      * This function checks the FailPoint currentOpSpawnsThreadWaitingForLatch and potentially
diff --git a/src/mongo/util/diagnostic_info_test.cpp b/src/mongo/util/diagnostic_info_test.cpp
index f8514525084..365f37ae9c1 100644
--- a/src/mongo/util/diagnostic_info_test.cpp
+++ b/src/mongo/util/diagnostic_info_test.cpp
@@ -47,8 +47,10 @@ TEST(DiagnosticInfo, BasicSingleThread) {
     serviceContext->setFastClockSource(std::move(clockSource));
     setGlobalServiceContext(std::move(serviceContext));
 
+    ThreadClient tc("DiagnosticInfoTest", getGlobalServiceContext());
+
     // take the initial diagnostic info
-    DiagnosticInfo capture1 = DiagnosticInfo::capture("capture1"_sd);
+    DiagnosticInfo capture1 = DiagnosticInfo::capture(tc.get(), "capture1"_sd);
     ASSERT_EQ(capture1.getCaptureName(), "capture1");
 
     // mock time advancing and check that the current time is greater than capture1's timestamp
@@ -56,7 +58,7 @@ TEST(DiagnosticInfo, BasicSingleThread) {
     ASSERT_LT(capture1.getTimestamp(), clockSourcePointer->now());
 
     // take a second diagnostic capture and compare its fields to the first
-    DiagnosticInfo capture2 = DiagnosticInfo::capture("capture2"_sd);
+    DiagnosticInfo capture2 = DiagnosticInfo::capture(tc.get(), "capture2"_sd);
     ASSERT_LT(capture1.getTimestamp(), capture2.getTimestamp());
     ASSERT_EQ(capture2.getCaptureName(), "capture2");
     ASSERT_NE(capture2, capture1);