trace2: create new combined trace facility
authorJeff Hostetler <jeffhost@microsoft.com>
Fri, 22 Feb 2019 22:25:01 +0000 (14:25 -0800)
committerJunio C Hamano <gitster@pobox.com>
Fri, 22 Feb 2019 23:27:59 +0000 (15:27 -0800)
commitee4512ed481a126dadd33334186e0e759d7f2f47
tree4bc0418115d44b1833c1d24d2ac1c92f067b7ad3
parente544221d97a57a9be7ba18a0df52a15b4cc76f97
trace2: create new combined trace facility

Create a new unified tracing facility for git.  The eventual intent is to
replace the current trace_printf* and trace_performance* routines with a
unified set of git_trace2* routines.

In addition to the usual printf-style API, trace2 provides higer-level
event verbs with fixed-fields allowing structured data to be written.
This makes post-processing and analysis easier for external tools.

Trace2 defines 3 output targets.  These are set using the environment
variables "GIT_TR2", "GIT_TR2_PERF", and "GIT_TR2_EVENT".  These may be
set to "1" or to an absolute pathname (just like the current GIT_TRACE).

* GIT_TR2 is intended to be a replacement for GIT_TRACE and logs command
  summary data.

* GIT_TR2_PERF is intended as a replacement for GIT_TRACE_PERFORMANCE.
  It extends the output with columns for the command process, thread,
  repo, absolute and relative elapsed times.  It reports events for
  child process start/stop, thread start/stop, and per-thread function
  nesting.

* GIT_TR2_EVENT is a new structured format. It writes event data as a
  series of JSON records.

Calls to trace2 functions log to any of the 3 output targets enabled
without the need to call different trace_printf* or trace_performance*
routines.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
39 files changed:
Makefile
builtin/submodule--helper.c
cache.h
common-main.c
compat/mingw.c
compat/mingw.h
config.c
exec-cmd.c
git-compat-util.h
git.c
remote-curl.c
repository.c
repository.h
run-command.c
run-command.h
sh-i18n--envsubst.c
submodule.c
t/helper/test-parse-options.c
t/helper/test-tool.c
t/t0001-init.sh
trace2.c [new file with mode: 0644]
trace2.h [new file with mode: 0644]
trace2/tr2_cfg.c [new file with mode: 0644]
trace2/tr2_cfg.h [new file with mode: 0644]
trace2/tr2_cmd_name.c [new file with mode: 0644]
trace2/tr2_cmd_name.h [new file with mode: 0644]
trace2/tr2_dst.c [new file with mode: 0644]
trace2/tr2_dst.h [new file with mode: 0644]
trace2/tr2_sid.c [new file with mode: 0644]
trace2/tr2_sid.h [new file with mode: 0644]
trace2/tr2_tbuf.c [new file with mode: 0644]
trace2/tr2_tbuf.h [new file with mode: 0644]
trace2/tr2_tgt.h [new file with mode: 0644]
trace2/tr2_tgt_event.c [new file with mode: 0644]
trace2/tr2_tgt_normal.c [new file with mode: 0644]
trace2/tr2_tgt_perf.c [new file with mode: 0644]
trace2/tr2_tls.c [new file with mode: 0644]
trace2/tr2_tls.h [new file with mode: 0644]
usage.c