commit 80872bddcc529d750c12349675504ea00271712a
author Dominik Laskowski <domlaskowski@google.com> Tue Nov 15 11:34:33 2022 -0500
committer Dominik Laskowski <domlaskowski@google.com> Tue Apr 18 19:28:35 2023 -0400
tree 3e151d2772fe229b1bc94d11d718294e1af2427c
parent ccda33e2eb762b0f9ffff3de982011b6fc7f84ec

SF: Clean up ftl::SmallMap lookup fallbacks

Avoid std::cref to a local variable, which is not intuitive and incurs
construction in the non-fallback case.

Bug: 185536303
Test: ftl_test
Change-Id: I1c5a94bdab105a04f8230fe762bdc433eea5c97a

services/surfaceflinger/Scheduler/RefreshRateStats.h

diff --git a/services/surfaceflinger/Scheduler/RefreshRateStats.h b/services/surfaceflinger/Scheduler/RefreshRateStats.h
index ed65bc6..67e1b9c 100644
--- a/services/surfaceflinger/Scheduler/RefreshRateStats.h
+++ b/services/surfaceflinger/Scheduler/RefreshRateStats.h
@@ -22,6 +22,7 @@
 #include <string>
 
 #include <android-base/stringprintf.h>
+#include <ftl/algorithm.h>
 #include <ftl/small_map.h>
 #include <utils/Timers.h>
 
@@ -82,12 +83,18 @@
         flushTime();
 
         TotalTimes totalTimes = ftl::init::map("ScreenOff", mScreenOffTime);
-        const auto zero = std::chrono::milliseconds::zero();
 
         // Sum the times for modes that map to the same name, e.g. "60 Hz".
         for (const auto& [fps, time] : mFpsTotalTimes) {
             const auto string = to_string(fps);
-            const auto total = std::as_const(totalTimes).get(string).value_or(std::cref(zero));
+            const auto total = std::as_const(totalTimes)
+                                       .get(string)
+                                       .or_else(ftl::static_ref<std::chrono::milliseconds>([] {
+                                           using namespace std::chrono_literals;
+                                           return 0ms;
+                                       }))
+                                       .value();
+
             totalTimes.emplace_or_replace(string, total.get() + time);
         }
 
@@ -114,15 +121,18 @@
         mPreviousRecordedTime = currentTime;
 
         const auto duration = std::chrono::milliseconds{ns2ms(timeElapsed)};
-        const auto zero = std::chrono::milliseconds::zero();
-
         uint32_t fps = 0;
 
         if (mCurrentPowerMode == PowerMode::ON) {
             // Normal power mode is counted under different config modes.
             const auto total = std::as_const(mFpsTotalTimes)
                                        .get(mCurrentRefreshRate)
-                                       .value_or(std::cref(zero));
+                                       .or_else(ftl::static_ref<std::chrono::milliseconds>([] {
+                                           using namespace std::chrono_literals;
+                                           return 0ms;
+                                       }))
+                                       .value();
+
             mFpsTotalTimes.emplace_or_replace(mCurrentRefreshRate, total.get() + duration);
 
             fps = static_cast<uint32_t>(mCurrentRefreshRate.getIntValue());

services/surfaceflinger/Scheduler/Scheduler.h

diff --git a/services/surfaceflinger/Scheduler/Scheduler.h b/services/surfaceflinger/Scheduler/Scheduler.h
index 720a1cb..4b2983b 100644
--- a/services/surfaceflinger/Scheduler/Scheduler.h
+++ b/services/surfaceflinger/Scheduler/Scheduler.h
@@ -32,6 +32,7 @@
 #include <ui/GraphicTypes.h>
 #pragma clang diagnostic pop // ignored "-Wconversion -Wextra"
 
+#include <ftl/algorithm.h>
 #include <ftl/fake_guard.h>
 #include <ftl/optional.h>
 #include <scheduler/Features.h>
@@ -438,13 +439,13 @@
 
     RefreshRateSelectorPtr pacesetterSelectorPtrLocked() const REQUIRES(mDisplayLock) {
         ftl::FakeGuard guard(kMainThreadContext);
-        const RefreshRateSelectorPtr noPacesetter;
         return mPacesetterDisplayId
                 .and_then([this](PhysicalDisplayId pacesetterId)
                                   REQUIRES(mDisplayLock, kMainThreadContext) {
                                       return mRefreshRateSelectors.get(pacesetterId);
                                   })
-                .value_or(std::cref(noPacesetter));
+                .or_else(ftl::static_ref<RefreshRateSelectorPtr>([] { return nullptr; }))
+                .value();
     }
 
     std::shared_ptr<const VsyncSchedule> getVsyncScheduleLocked(

services/surfaceflinger/SurfaceFlinger.h

diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index eb9dc74..04fcfb9 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -28,6 +28,7 @@
 #include <android/gui/ISurfaceComposerClient.h>
 #include <cutils/atomic.h>
 #include <cutils/compiler.h>
+#include <ftl/algorithm.h>
 #include <ftl/future.h>
 #include <ftl/non_null.h>
 #include <gui/BufferQueue.h>
@@ -854,8 +855,9 @@
     }
 
     sp<DisplayDevice> getDisplayDeviceLocked(const wp<IBinder>& displayToken) REQUIRES(mStateLock) {
-        const sp<DisplayDevice> nullDisplay;
-        return mDisplays.get(displayToken).value_or(std::cref(nullDisplay));
+        return mDisplays.get(displayToken)
+                .or_else(ftl::static_ref<sp<DisplayDevice>>([] { return nullptr; }))
+                .value();
     }
 
     sp<const DisplayDevice> getDisplayDeviceLocked(PhysicalDisplayId id) const
@@ -1011,10 +1013,10 @@
      */
     sp<display::DisplayToken> getPhysicalDisplayTokenLocked(PhysicalDisplayId displayId) const
             REQUIRES(mStateLock) {
-        const sp<display::DisplayToken> nullToken;
         return mPhysicalDisplays.get(displayId)
                 .transform([](const display::PhysicalDisplay& display) { return display.token(); })
-                .value_or(std::cref(nullToken));
+                .or_else([] { return std::optional<sp<display::DisplayToken>>(nullptr); })
+                .value();
     }
 
     std::optional<PhysicalDisplayId> getPhysicalDisplayIdLocked(