Commit graph

11 commits

Author SHA1 Message Date
René Scharfe
5c34d2f03e trace2: add dots directly to strbuf in perf_fmt_prepare()
The initialization function of the Trace2 performance format target sets
aside a stash of dots for indenting output.  Get rid of it and use
strbuf_addchars() to provide dots on demand instead.  This shortens the
code, gets rid of a small heap allocation and is a bit more efficient.

Signed-off-by: René Scharfe <l.s.r@web.de>
Acked-by: Jeff King <peff@peff.net>
Acked-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-11-06 11:45:18 +09:00
Josh Steadmon
87db61a436 trace2: write discard message to sentinel files
Add a new "discard" event type for trace2 event destinations. When the
trace2 file count check creates a sentinel file, it will include the
normal trace2 output in the sentinel, along with this new discard
event.

Writing this message into the sentinel file is useful for tracking how
often the file count check triggers in practice.

Bump up the event format version since we've added a new event type.

Signed-off-by: Josh Steadmon <steadmon@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-05 17:53:51 +09:00
Jeff Hostetler
742ed63345 trace2: cleanup whitespace in perf format
Make use of new sq_append_quote_argv_pretty() to normalize
how we handle leading whitespace in perf format messages.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-08-09 10:48:02 -07:00
Jeff Hostetler
04f10d332f trace2: remove dead code in maybe_add_string_va()
Remove an unnecessary "if" block in maybe_add_string_va().

Commit "ad006fe419e trace2: NULL is not allowed for va_list"
changed "if (fmt && *fmt && ap)" to just "if (fmt && *fmt)"
because it isn't safe to treat 'ap' as a pointer.  This made
the "if" block following it unnecessary.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-08-08 10:39:44 -07:00
Jeff Hostetler
da4589ce7e trace2: trim whitespace in region messages in perf target format
Avoid unecessary trailing whitespace in "region_enter" and "region_leave"
messages in perf target format.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-08-08 10:39:44 -07:00
Jeff Hostetler
371df1bea9 trace2: cleanup column alignment in perf target format
Truncate/elide very long "filename:linenumber" field.
Truncate region and data "category" field if necessary.
Adjust overall column widths.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-08-01 14:36:42 -07:00
Junio C Hamano
5b2d1c0c6e Merge branch 'jh/trace2-sid-fix'
Polishing of the new trace2 facility continues.  The system-level
configuration can specify site-wide trace2 settings, which can be
overridden with per-user configuration and environment variables.

* jh/trace2-sid-fix:
  trace2: fixup access problem on /etc/gitconfig in read_very_early_config
  trace2: update docs to describe system/global config settings
  trace2: make SIDs more unique
  trace2: clarify UTC datetime formatting
  trace2: report peak memory usage of the process
  trace2: use system/global config for default trace2 settings
  config: add read_very_early_config()
  trace2: find exec-dir before trace2 initialization
  trace2: add absolute elapsed time to start event
  trace2: refactor setting process starting time
  config: initialize opts structure in repo_read_config()
2019-05-13 23:50:31 +09:00
Jeff Hostetler
bce9db6de9 trace2: use system/global config for default trace2 settings
Teach git to read the system and global config files for
default Trace2 settings.  This allows system-wide Trace2 settings to
be installed and inherited to make it easier to manage a collection of
systems.

The original GIT_TR2* environment variables are loaded afterwards and
can be used to override the system settings.

Only the system and global config files are used.  Repo and worktree
local config files are ignored.  Likewise, the "-c" command line
arguments are also ignored.  These limits are for performance reasons.

(1) For users not using Trace2, there should be minimal overhead to
detect that Trace2 is not enabled.  In particular, Trace2 should not
allocate lots of otherwise unused data strucutres.

(2) For accurate performance measurements, Trace2 should be initialized
as early in the git process as possible, and before most of the normal
git process initialization (which involves discovering the .git directory
and reading a hierarchy of config files).

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-04-16 13:37:06 +09:00
Jeff Hostetler
39f4317744 trace2: add absolute elapsed time to start event
Add elapsed process time to "start" event to measure
the performance of early process startup.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-04-16 13:37:06 +09:00
Torsten Bögershausen
ad006fe419 trace2: NULL is not allowed for va_list
Some compilers don't allow NULL to be passed for a va_list,
and e.g. "gcc (Raspbian 6.3.0-18+rpi1+deb9u1) 6.3.0 20170516"
errors out like this:
 trace2/tr2_tgt_event.c:193:18:
   error: invalid operands to binary &&
   (have ‘int’ and ‘va_list {aka __va_list}’)
    if (fmt && *fmt && ap) {
                       ^^
I couldn't find any hints that va_list and pointers can be mixed,
and no hints that they can't either. Morten Welinder comments:

"C99, Section 7.15, simply says that va_list "is an object type suitable for
holding information needed by the macros va_start, va_end, and
va_copy". So clearly not guaranteed to be mixable with pointers...

The portable solution is to use "va_list" everywhere in the callchain.
As a consequence, both trace2_region_enter_fl() and trace2_region_leave_fl()
now take a variable argument list.

Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Acked-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-03-20 09:48:53 +09:00
Jeff Hostetler
ee4512ed48 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>
2019-02-22 15:27:59 -08:00