Revert "logd: drop mSequence from LogBufferElement"
This reverts commit 5a34d6ea43d28f3b5d27bf6dd5b9fa31ec033531.
There is a long standing bug that logd will leak memory during its
prune process if the time on the device changes significantly forwards
then backwards. This is due to using the timestamp of each log
message to determine what log messages are yet to be processed by a
reader thread.
Various attempts have been made to rectify this, but the only solution
that safely fixes this issue is to go back to using sequence numbers
on the log messages.
Bug: 64675203
Bug: 77971811
Bug: 149340579
Bug: 150923384
Test: logcat output looks sane
Change-Id: Ibce79cf184eb29a4914f3e42a8cb2868d04dc165
diff --git a/logd/LogBufferElement.cpp b/logd/LogBufferElement.cpp
index ec81933..3714800 100644
--- a/logd/LogBufferElement.cpp
+++ b/logd/LogBufferElement.cpp
@@ -30,15 +30,15 @@
#include "LogReader.h"
#include "LogUtils.h"
-const log_time LogBufferElement::FLUSH_ERROR((uint32_t)-1, (uint32_t)-1);
+const uint64_t LogBufferElement::FLUSH_ERROR(0);
atomic_int_fast64_t LogBufferElement::sequence(1);
-LogBufferElement::LogBufferElement(log_id_t log_id, log_time realtime,
- uid_t uid, pid_t pid, pid_t tid,
- const char* msg, uint16_t len)
+LogBufferElement::LogBufferElement(log_id_t log_id, log_time realtime, uid_t uid, pid_t pid,
+ pid_t tid, const char* msg, uint16_t len)
: mUid(uid),
mPid(pid),
mTid(tid),
+ mSequence(sequence.fetch_add(1, memory_order_relaxed)),
mRealTime(realtime),
mMsgLen(len),
mLogId(log_id),
@@ -51,6 +51,7 @@
: mUid(elem.mUid),
mPid(elem.mPid),
mTid(elem.mTid),
+ mSequence(elem.mSequence),
mRealTime(elem.mRealTime),
mMsgLen(elem.mMsgLen),
mLogId(elem.mLogId),
@@ -244,7 +245,7 @@
return retval;
}
-log_time LogBufferElement::flushTo(SocketClient* reader, LogBuffer* parent, bool lastSame) {
+uint64_t LogBufferElement::flushTo(SocketClient* reader, LogBuffer* parent, bool lastSame) {
struct logger_entry entry = {};
entry.hdr_size = sizeof(struct logger_entry);
@@ -263,7 +264,7 @@
if (mDropped) {
entry.len = populateDroppedMessage(buffer, parent, lastSame);
- if (!entry.len) return mRealTime;
+ if (!entry.len) return mSequence;
iovec[1].iov_base = buffer;
} else {
entry.len = mMsgLen;
@@ -271,9 +272,7 @@
}
iovec[1].iov_len = entry.len;
- log_time retval = reader->sendDatav(iovec, 1 + (entry.len != 0))
- ? FLUSH_ERROR
- : mRealTime;
+ uint64_t retval = reader->sendDatav(iovec, 1 + (entry.len != 0)) ? FLUSH_ERROR : mSequence;
if (buffer) free(buffer);