On Tue, Nov 24, 2020 at 05:02:51PM +0100, Gerd Hoffmann wrote: > First version that actually works. Only qxl covered for this RfC, other > modules will follow once the basics are hashed out. > > More context: > https://bugzilla.redhat.com/show_bug.cgi?id=1898700 > https://bugzilla.redhat.com/show_bug.cgi?id=1869642 > > take care, > Gerd > > Gerd Hoffmann (4): > meson: add trace_events_config[] > meson: move up hw subdir (specifically before trace subdir) > meson: add module_trace & module_trace_src > meson: move qxl trace events to separate file
Awesome, thank you for working on this! I noticed an issue with simpletrace: the trace file does not contain qxl_* TRACE_RECORD_TYPE_MAPPING records when ./configure --enable-modules is used. This happens because st_write_event_mapping() is called before the qxl module calls trace_event_register_group(). (The mapping records describe the integer ID to string name mapping used in a simpletrace file.) You can check this using "grep -a qxl_ trace-$LAST_QEMU_PID" after running qemu --device qxl built with ./configure --enable-modules --enable-trace-backend=simple. Remove --enable-modules and the file will contain the qxl_ trace events. This means the trace file is broken because the simpletrace records cannot be mapped to a trace event name. One way to solve this is by modifying trace_event_register_group() to call into trace/simple.c (maybe with a TraceEventIter initialized to iterate over the newly registered trace events group?). Alternatively, simpletrace.c might be able to emit TRACE_RECORD_TYPE_MAPPING on demand instead of ahead of time. Stefan
signature.asc
Description: PGP signature
