tree 018f14b5f093fcb34328b57da477247d6a33b5c7
parent db3cfff200e5465824641f0a4a4ee0f19b3ab76f
author Willy Tarreau <w@1wt.eu> 1565628123 +0200
committer Willy Tarreau <w@1wt.eu> 1567095732 +0200
encoding latin1

MEDIUM: mux-h2/trace: add lots of traces all over the code

All functions of the h2 data path were updated to receive one or multiple
TRACE() calls, at least one pair of TRACE_ENTER()/TRACE_LEAVE(), and those
manipulating protocol elements have been improved to report frame types,
special state transitions or detected errors. Even with careful tests, no
performance impact was measured when traces are disabled.

They are not completely exploited yet, the callback function tries to
dump a lot about them, but still doesn't provide buffer dumps, nor does
it indicate the stream or connection error codes.

The first argument is always set to the connection when known. The second
argument is set to the h2s when known, sometimes a 3rd argument is set to
a buffer, generally the rxbuf or htx, and occasionally the 4th argument
points to an integer (number of bytes read/sent, error code).

Retrieving a 10kB object produces roughly 240 lines when at developer
level, 35 lines at data level, 27 at state level, and 10 at proto level
and 2 at user level.

For now the headers are not dumped, but the start line are emitted in
each direction at user level.

The patch is marked medium because it touches lots of places, though
it takes care not to change the execution path.