commit bc8281abc10ba1c259241252fc409b77fe6828e8
author Eric Tan <taneric@google.com> Thu Sep 20 10:16:14 2018 -0700
committer Eric Tan <taneric@google.com> Thu Sep 20 10:16:14 2018 -0700
tree 0dd0fe5c3dc2f286f2f62427ae12e5d2cd29c716
parent ea055e6dab6bcbf9bf90711d602bcf59395f0d59

NBLog: add retroactive dump and standard printing format

The retroactive dump outputs historical snapshots of data that
correspond to important NBLog Events at the time they were read.

The standard printing format added is as follows: for each line, the
first column is the NBLog Event as a string, and the following columns
correspond to each field of the struct, or the type, that the NBLog
Event maps to. All columns are separated by commas.

Other changes:
Added option to Reader::getSnapshot() for flushing the buffer. This
makes it possible to always read the full buffer contents when doing a
dump of the raw log contents.

Test: dumpsys media.log with -r and --retro options
Bug: 68148948
Change-Id: I4bbbf6e2f9a3a86fae976986ac35a7eef79520de

media/libnblog/Reader.cpp

diff --git a/media/libnblog/Reader.cpp b/media/libnblog/Reader.cpp
index f86bb99..dfad332 100644
--- a/media/libnblog/Reader.cpp
+++ b/media/libnblog/Reader.cpp
@@ -59,7 +59,7 @@
 // Copies content of a Reader FIFO into its Snapshot
 // The Snapshot has the same raw data, but represented as a sequence of entries
 // and an EntryIterator making it possible to process the data.
-std::unique_ptr<Snapshot> Reader::getSnapshot()
+std::unique_ptr<Snapshot> Reader::getSnapshot(bool flush)
 {
     if (mFifoReader == NULL) {
         return std::unique_ptr<Snapshot>(new Snapshot());
@@ -146,7 +146,9 @@
     }
 
     // advance fifo reader index to after last entry read.
-    mFifoReader->release(snapshot->mEnd - front);
+    if (flush) {
+        mFifoReader->release(snapshot->mEnd - front);
+    }
 
     snapshot->mLost = lost;
     return snapshot;
@@ -221,36 +223,48 @@
 void DumpReader::dump(int fd, size_t indent)
 {
     if (fd < 0) return;
-    std::unique_ptr<Snapshot> snapshot = getSnapshot();
+    std::unique_ptr<Snapshot> snapshot = getSnapshot(false /*flush*/);
     if (snapshot == nullptr) {
         return;
     }
     String8 timestamp, body;
 
     // TODO all logged types should have a printable format.
+    // TODO can we make the printing generic?
     for (EntryIterator it = snapshot->begin(); it != snapshot->end(); ++it) {
         switch (it->type) {
         case EVENT_FMT_START:
             it = handleFormat(FormatEntry(it), &timestamp, &body);
             break;
-        case EVENT_WORK_TIME: {
-            const int64_t monotonicNs = it.payload<int64_t>();
-            body.appendFormat("Thread cycle: %ld ns", (long)monotonicNs);
-        } break;
         case EVENT_LATENCY: {
             const double latencyMs = it.payload<double>();
-            body.appendFormat("latency: %.3f ms", latencyMs);
+            body.appendFormat("EVENT_LATENCY,%.3f", latencyMs);
+        } break;
+        case EVENT_OVERRUN: {
+            const int64_t ts = it.payload<int64_t>();
+            body.appendFormat("EVENT_OVERRUN,%lld", static_cast<long long>(ts));
+        } break;
+        case EVENT_THREAD_INFO: {
+            const thread_info_t info = it.payload<thread_info_t>();
+            body.appendFormat("EVENT_THREAD_INFO,%d,%s", static_cast<int>(info.id),
+                    threadTypeToString(info.type));
+        } break;
+        case EVENT_UNDERRUN: {
+            const int64_t ts = it.payload<int64_t>();
+            body.appendFormat("EVENT_UNDERRUN,%lld", static_cast<long long>(ts));
         } break;
         case EVENT_WARMUP_TIME: {
             const double timeMs = it.payload<double>();
-            body.appendFormat("warmup time: %.3f ms", timeMs);
+            body.appendFormat("EVENT_WARMUP_TIME,%.3f", timeMs);
         } break;
-        case EVENT_UNDERRUN:
-            body.appendFormat("underrun");
-            break;
-        case EVENT_OVERRUN:
-            body.appendFormat("overrun");
-            break;
+        case EVENT_WORK_TIME: {
+            const int64_t monotonicNs = it.payload<int64_t>();
+            body.appendFormat("EVENT_WORK_TIME,%lld", static_cast<long long>(monotonicNs));
+        } break;
+        case EVENT_THREAD_PARAMS: {
+            const thread_params_t params = it.payload<thread_params_t>();
+            body.appendFormat("EVENT_THREAD_PARAMS,%zu,%u", params.frameCount, params.sampleRate);
+        } break;
         case EVENT_FMT_END:
         case EVENT_RESERVED:
         case EVENT_UPPER_BOUND: