Track QuicChromiumClientSession in net/ MemoryDumpProvider

net/quic/chromium/quic_chromium_client_session.cc

Index: net/quic/chromium/quic_chromium_client_session.cc
diff --git a/net/quic/chromium/quic_chromium_client_session.cc b/net/quic/chromium/quic_chromium_client_session.cc
index 96a8eea48f32dd156b9163dcdcca58891b2c6d69..3d7f644d12192007d53370b44fbb6ac55617f729 100644
--- a/net/quic/chromium/quic_chromium_client_session.cc
+++ b/net/quic/chromium/quic_chromium_client_session.cc
@@ -15,6 +15,7 @@
 #include "base/stl_util.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/threading/thread_task_runner_handle.h"
+#include "base/trace_event/memory_usage_estimator.h"
 #include "base/values.h"
 #include "net/base/io_buffer.h"
 #include "net/base/net_errors.h"
@@ -1519,4 +1520,10 @@ QuicVersion QuicChromiumClientSession::GetQuicVersion() const {
   return connection()->version();
 }
 
+size_t QuicChromiumClientSession::EstimateMemoryUsage() const {
+  // TODO(xunjieli): Estimate |crypto_stream_|, QuicSpdySession's
+  // QuicHeaderList and QuicSession's QuiCWriteBlockedList.

[Ryan Hamilton, 2017/01/25 23:52:00]

Would you also want to estimate any open streams? Would you also want to
estimate the memory usage from the unacked packet map? (packets which have been
sent but not received, in which case we need to keep the data around in case we
need to retransmit it)

[xunjieli, 2017/01/26 15:23:50]

Done. Added in the TODO.
I would like to estimate all non-trivial objects. Open streams are a good place
to do next. Thanks for the suggestions. My main focus right now is to
investigate  where //net memory is going when there are no active requests. The
next thing to investigate the "active requests" case.

One challenge I have with instrumenting QUIC code is that I might need to touch
/quic/core. 

Ryan: how do you feel about I land the change in chromium first and do an
upstream CL shortly after? Or do you prefer I go the other way?

[Ryan Hamilton, 2017/01/26 17:04:23]

Both can work, but it's usually better to land internally first. However,
sometimes I'll do this by:
1) Write the CL in chrome. *iterate*
2) When finished, make the changes in an internal CL and send that for review.
3) When it lands, marge any changes from the review back to your chrome CL and
land that.

[xunjieli, 2017/01/26 18:42:08]

Acknowledged. Got it. Will do that.

+  return base::trace_event::EstimateMemoryUsage(packet_readers_);
+}
+
 }  // namespace net