common_time: Turn the logging up to 11
Hand merge from ics-aah
> DO NOT MERGE: common_time: Turn the logging up to 11
>
> Actually, despite the CL title, no addition log messages are being
> sent to logcat. Generally speaking, the common_time service tends to
> be rather quiet from a log perspective. Events related to master
> election and arbitration as well as state changes tend to be
> infrequent in steady state operation. Unfortunately, if there is a
> problem with the system, it frequently gets pushed out of logcat by
> other messages and is missing from the logs when a bugreport is
> finally taken.
>
> This change adds a utility class which can be used to store the last N
> log message in a ring buffer to be dumped later during a dumpsys
> operation. Three internal log buffers were added to the system. One
> to record messages having to do with state transitions. Another was
> added to record traffic relating to master election, and one final
> buffer to record basic data on packets which were received but
> discarded for any reason. During a bugreport, these common_time.clock
> service will be able to dump these messages regardless of the amt of
> other logcat activity, which should assist in debugging long running
> issues.
>
> Change-Id: Ic3bbf7480c8978f9bf82bafaba04cf4586db60cf
> Signed-off-by: John Grossman <johngro@google.com>
Change-Id: If7156d41ce4553d5ba5c3a8e1dd616564a569711
Signed-off-by: John Grossman <johngro@google.com>
diff --git a/services/common_time/utils.h b/services/common_time/utils.h
index d3545c9..c28cf0a 100644
--- a/services/common_time/utils.h
+++ b/services/common_time/utils.h
@@ -20,6 +20,8 @@
#include <stdint.h>
#include <unistd.h>
+#include <utils/String8.h>
+#include <utils/threads.h>
#include <utils/Timers.h>
namespace android {
@@ -43,6 +45,39 @@
nsecs_t mSystemEndTime;
};
+class LogRing {
+ public:
+ LogRing(const char* header, size_t entries);
+ ~LogRing();
+
+ // Send a log message to logcat as well as storing it in the ring buffer.
+ void log(int prio, const char* tag, const char* fmt, ...);
+
+ // Add a log message the ring buffer, do not send the message to logcat.
+ void log(const char* fmt, ...);
+
+ // Dump the log to an fd (dumpsys style)
+ void dumpLog(int fd);
+
+ private:
+ class Entry {
+ public:
+ uint32_t count;
+ struct timeval first_ts;
+ struct timeval last_ts;
+ String8 s;
+ };
+
+ Mutex mLock;
+ Entry* mRingBuffer;
+ size_t mSize;
+ size_t mWr;
+ bool mIsFull;
+ const char* mHeader;
+
+ void internalLog(int prio, const char* tag, const char* fmt, va_list va);
+};
+
} // namespace android
#endif // __UTILS_H__