Adjust technical/bitmap-format to be formatted by AsciiDoc, and
add some missing information to the documentation.
* ac/bitmap-format-doc:
bitmap-format.txt: add information for trailing checksum
bitmap-format.txt: fix some formatting issues
bitmap-format.txt: feed the file to asciidoc to generate html
Bitmap file has a trailing checksum at the end of the file. However
there is no information in the bitmap-format documentation about it.
Add a trailer section to include the trailing checksum info in the
`Documentation/technical/bitmap-format.txt` file.
Signed-off-by: Abhradeep Chakraborty <chakrabortyabhradeep79@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The asciidoc generated html for `Documentation/technical/bitmap-
format.txt` is broken. This is mainly because `-` is used for nested
lists (which is not allowed in asciidoc) instead of `*`.
Fix these and also reformat it for better readability of the html page.
Signed-off-by: Abhradeep Chakraborty <chakrabortyabhradeep79@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A new bug() and BUG_if_bug() API is introduced to make it easier to
uniformly log "detect multiple bugs and abort in the end" pattern.
* ab/bug-if-bug:
cache-tree.c: use bug() and BUG_if_bug()
receive-pack: use bug() and BUG_if_bug()
parse-options.c: use optbug() instead of BUG() "opts" check
parse-options.c: use new bug() API for optbug()
usage.c: add a non-fatal bug() function to go with BUG()
common-main.c: move non-trace2 exit() behavior out of trace2.c
A mechanism to pack unreachable objects into a "cruft pack",
instead of ejecting them into loose form to be reclaimed later, has
been introduced.
* tb/cruft-packs:
sha1-file.c: don't freshen cruft packs
builtin/gc.c: conditionally avoid pruning objects via loose
builtin/repack.c: add cruft packs to MIDX during geometric repack
builtin/repack.c: use named flags for existing_packs
builtin/repack.c: allow configuring cruft pack generation
builtin/repack.c: support generating a cruft pack
builtin/pack-objects.c: --cruft with expiration
reachable: report precise timestamps from objects in cruft packs
reachable: add options to add_unseen_recent_objects_to_traversal
builtin/pack-objects.c: --cruft without expiration
builtin/pack-objects.c: return from create_object_entry()
t/helper: add 'pack-mtimes' test-tool
pack-mtimes: support writing pack .mtimes files
chunk-format.h: extract oid_version()
pack-write: pass 'struct packing_data' to 'stage_tmp_packfiles'
pack-mtimes: support reading .mtimes files
Documentation/technical: add cruft-packs.txt
Add a bug() function to use in cases where we'd like to indicate a
runtime BUG(), but would like to defer the BUG() call because we're
possibly accumulating more bug() callers to exhaustively indicate what
went wrong.
We already have this sort of facility in various parts of the
codebase, just in the form of ad-hoc re-inventions of the
functionality that this new API provides. E.g. this will be used to
replace optbug() in parse-options.c, and the 'error("BUG:[...]' we do
in a loop in builtin/receive-pack.c.
Unlike the code this replaces we'll log to trace2 with this new bug()
function (as with other usage.c functions, including BUG()), we'll
also be able to avoid calls to xstrfmt() in some cases, as the bug()
function itself accepts variadic sprintf()-like arguments.
Any caller to bug() can follow up such calls with BUG_if_bug(),
which will BUG() out (i.e. abort()) if there were any preceding calls
to bug(), callers can also decide not to call BUG_if_bug() and leave
the resulting BUG() invocation until exit() time. There are currently
no bug() API users that don't call BUG_if_bug() themselves after a
for-loop, but allowing for not calling BUG_if_bug() keeps the API
flexible. As the tests and documentation here show we'll catch missing
BUG_if_bug() invocations in our exit() wrapper.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Expose a way to split the contents of a repository into a main and cruft
pack when doing an all-into-one repack with `git repack --cruft -d`, and
a complementary configuration variable.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To store the individual mtimes of objects in a cruft pack, introduce a
new `.mtimes` format that can optionally accompany a single pack in the
repository.
The format is defined in Documentation/technical/pack-format.txt, and
stores a 4-byte network order timestamp for each object in name (index)
order.
This patch prepares for cruft packs by defining the `.mtimes` format,
and introducing a basic API that callers can use to read out individual
mtimes.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Create a technical document to explain cruft packs. It contains a brief
overview of the problem, some background, details on the implementation,
and a couple of alternative approaches not considered here.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The example was not in valid JSON format due to a duplicate key "sid".
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We append an ellipsis and enclose it in backticks to indicate that it is
a function elsewhere, let's also use that here.
While at it, ensure the same for `waitpid()`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git fetch --refetch" learned to fetch everything without telling
the other side what we already have, which is useful when you
cannot trust what you have in the local object store.
* rc/fetch-refetch:
docs: mention --refetch fetch option
fetch: after refetch, encourage auto gc repacking
t5615-partial-clone: add test for fetch --refetch
fetch: add --refetch option
builtin/fetch-pack: add --refetch option
fetch-pack: add refetch
fetch-negotiator: add specific noop initializer
Document it for partial clones as a means to apply a new filter, and
reference it from the remote.<name>.partialclonefilter config parameter.
Signed-off-by: Robert Coup <robert@coup.net.nz>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Bundle file format gets extended to allow a partial bundle,
filtered by similar criteria you would give when making a
partial/lazy clone.
* ds/partial-bundles:
clone: fail gracefully when cloning filtered bundle
bundle: unbundle promisor packs
bundle: create filtered bundles
rev-list: move --filter parsing into revision.c
bundle: parse filter capability
list-objects: handle NULL function pointers
MyFirstObjectWalk: update recommended usage
list-objects: consolidate traverse_commit_list[_filtered]
pack-bitmap: drop filter in prepare_bitmap_walk()
pack-objects: use rev.filter when possible
revision: put object filter into struct rev_info
list-objects-filter-options: create copy helper
index-pack: document and test the --promisor option
Fixes to the way generation number v2 in the commit-graph files are
(not) handled.
* ds/commit-graph-gen-v2-fixes:
commit-graph: declare bankruptcy on GDAT chunks
commit-graph: fix generation number v2 overflow values
commit-graph: start parsing generation v2 (again)
commit-graph: fix ordering bug in generation numbers
t5318: extract helpers to lib-commit-graph.sh
test-read-graph: include extra post-parse info
The v3 bundle format has capabilities, allowing newer versions of Git to
create bundles with newer features. Older versions that do not
understand these new capabilities will fail with a helpful warning.
Create a new capability allowing Git to understand that the contained
pack-file is filtered according to some object filter. Typically, this
filter will be "blob:none" for a blobless partial clone.
This change teaches Git to parse this capability, place its value in the
bundle header, and demonstrate this understanding by adding a message to
'git bundle verify'.
Since we will use gently_parse_list_objects_filter() outside of
list-objects-filter-options.c, make it an external method and move its
API documentation to before its declaration.
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The Generation Data (GDAT) and Generation Data Overflow (GDOV) chunks
store corrected commit date offsets, used for generation number v2.
Recent changes have demonstrated that previous versions of Git were
incorrectly parsing data from these chunks, but might have also been
writing them incorrectly.
I asserted [1] that the previous fixes were sufficient because the known
reasons for incorrectly writing generation number v2 data relied on
parsing the information incorrectly out of a commit-graph file, but the
previous versions of Git were not reading the generation number v2 data.
However, Patrick demonstrated [2] a case where in split commit-graphs
across an alternate boundary (and possibly some other special
conditions) it was possible to have a commit-graph that was generated by
a previous version of Git have incorrect generation number v2 data which
results in errors like the following:
commit-graph generation for commit <oid> is 1623273624 < 1623273710
[1] https://lore.kernel.org/git/f50e74f0-9ffa-f4f2-4663-269801495ed3@github.com/
[2] https://lore.kernel.org/git/Yh93vOkt2DkrGPh2@ncase/
Clearly, there is something else going on. The situation is not
completely understood, but the errors do not reproduce if the
commit-graphs are all generated by a Git version including these recent
fixes.
If we cannot trust the existing data in the GDAT and GDOV chunks, then
we can alter the format to change the chunk IDs for these chunks. This
causes the new version of Git to silently ignore the older chunks (and
disabling generation number v2 in the process) while writing new
commit-graph files with correct data in the GDA2 and GDO2 chunks.
Update commit-graph-format.txt including a historical note about these
deprecated chunks.
Reported-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The value is stored in a 5-bit field, so we can't support more without
a format version upgrade.
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The previous patch demonstrates a bug where a MIDX's auxiliary object
order can become out of sync with a MIDX bitmap.
This is because of two confounding factors:
- First, the object order is stored in a file which is named according
to the multi-pack index's checksum, and the MIDX does not store the
object order. This means that the object order can change without
altering the checksum.
- But the .rev file is moved into place with finalize_object_file(),
which link(2)'s the file into place instead of renaming it. For us,
that means that a modified .rev file will not be moved into place if
MIDX's checksum was unchanged.
This fix is to force the MIDX's checksum to change when the preferred
pack changes but the set of packs contained in the MIDX does not. In
other words, when the object order changes, the MIDX's checksum needs to
change with it (regardless of whether the MIDX is tracking the same or
different packs).
This prevents a race whereby changing the object order (but not the
packs themselves) enables a reader to see the new .rev file with the old
MIDX, or similarly seeing the new bitmap with the old object order.
But why can't we just stop hardlinking the .rev into place instead
adding additional data to the MIDX? Suppose that's what we did. Then
when we go to generate the new bitmap, we'll load the old MIDX bitmap,
along with the MIDX that it references. That's fine, since the new MIDX
isn't moved into place until after the new bitmap is generated. But the
new object order *has* been moved into place. So we'll read the old
bitmaps in the new order when generating the new bitmap file, meaning
that without this secondary change, bitmap generation itself would
become a victim of the race described here.
This can all be prevented by forcing the MIDX's checksum to change when
the object order does. By embedding the entire object order into the
MIDX, we do just that. That is, the MIDX's checksum will change in
response to any perturbation of the underlying object order. In t5326,
this will cause the MIDX's checksum to update (even without changing the
set of packs in the MIDX), preventing the stale read problem.
Note that this makes it safe to continue to link(2) the MIDX .rev file
into place, since it is now impossible to have a .rev file that is
out-of-sync with the MIDX whose checksum it references. (But we will do
away with MIDX .rev files later in this series anyway, so this is
somewhat of a moot point).
In theory, it is possible to store a "fingerprint" of the full object
order here, so long as that fingerprint changes at least as often as the
full object order does. Some possibilities here include storing the
identity of the preferred pack, along with the mtimes of the
non-preferred packs in a consistent order. But storing a limited part of
the information makes it difficult to reason about whether or not there
are gaps between the two that would cause us to get bitten by this bug
again.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"Zealous diff3" style of merge conflict presentation has been added.
* en/zdiff3:
update documentation for new zdiff3 conflictStyle
xdiff: implement a zealous diff3, or "zdiff3"
The multi-pack index treats promisor packfiles (that is, packfiles that
have an accompanying .promisor file) the same as other packfiles. Remove
a section in the documentation that seems to indicate otherwise.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There is a formatting issue in "multi-pack-index.html", corresponding
to the nesting bulleted list of a wrong usage in "multi-pack-index.txt"
and this commit fix the problem.
In ASCIIDOC, it doesn't treat an indented character as the
beginning of a sub-list. If we want to write a nested bulleted list, we
could just use ASTERISK without any DASH like:
"
* Level 1 list item
** Level 2 list item
*** Level 3 list item
** Level 2 list item
* Level 1 list item
** Level 2 list item
* Level 1 list item
"
The DASH can be used for bulleted list too, But the DASH is suggested
only to be used as the marker for the first level because the DASH
doesn’t work well or a best practice for nested lists,
like (dash is as level 2 below):
"
* Level 1 list item
- Level 2 list item
* Level 1 list item
"
ASTERISK is recommanded to use because it works intuitively and clearly
("marker length = nesting level") in nested lists, but the DASH can't.
However, when you want to write a non-nested bulleted lists, DASH works
too, like:
"
- Level 1 list item
- Level 1 list item
- Level 1 list item
"
Reviewed-by: Taylor Blau <me@ttaylorr.com>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Teng Long <dyroneteng@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we added a new event type to trace2 event stream, we forgot to
raise the format version number, which has been corrected.
* js/trace2-raise-format-version:
trace2: increment event format version
In 64bc752 (trace2: add trace2_child_ready() to report on background
children, 2021-09-20), we added a new "child_ready" event. In
Documentation/technical/api-trace2.txt, we promise that adding a new
event type will result in incrementing the trace2 event format version
number, but this was not done. Correct this in code & docs.
Signed-off-by: Josh Steadmon <steadmon@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The current protocol EBNF allows command-request to end with the
capability list, if no command specific arguments follow, but the
protocol requires that after the capability list, there must be a
delim-pkt regardless of the number of command specific arguments. Fixed
the EBNF to match. Both JGit and libgit2's implementation has the
delim-pkt as mandatory. JGit's code is not publicly linkable, but
libgit2 is linked below[1]. As for currently implemented commands on v2
(ls-ref and fetch), the delim packet is already being passed through
[1]: https://github.com/libgit2/libgit2/blob/main/src/transports/git.c
Reported-by: Ivan Frade <ifrade@google.com>
Signed-off-by: Calvin Wan <calvinwan@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Built-in fsmonitor (part 1).
* jh/builtin-fsmonitor-part1:
t/helper/simple-ipc: convert test-simple-ipc to use start_bg_command
run-command: create start_bg_command
simple-ipc/ipc-win32: add Windows ACL to named pipe
simple-ipc/ipc-win32: add trace2 debugging
simple-ipc: move definition of ipc_active_state outside of ifdef
simple-ipc: preparations for supporting binary messages.
trace2: add trace2_child_ready() to report on background children
A signature attached to a signed commit, and the contents of the
commit that merged a signed tag, are both recorded as a value of an
object header field as a multi-line value, and are subject to the
formatting convention for multi-line values in the headers, with a
leading SP signaling that the rest of the line is a continuation of
the previous line. Most notably, an empty line in such a multi-line
value would result in a line with a sole SP on it.
Examples in the signature-format technical documentation include a
few of these cases but we did not show these otherwise invisible SPs
in the example. These trailing spaces cannot be seen on display or
on paper, and forces the readers to look for them in their editors
or pagers, even if we added them to the document.
Extend the overview section to explain the multi-line value
formatting and highlight these otherwise invisible SPs by inventing
the "a dollar-sign at the end of line that appears after SP merely
signals that there is a SP there, and the dollar-sign itself does
not appear in the real file" notation, inspired by "cat -e" output,
to help readers to learn exactly where such "a single SP that is
originally an empty line" appears in the examples.
Reported-by: Rob Browning <rlb@defaultvalue.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Code cleanup to limit memory consumption and tighten protocol
message parsing.
* jk/reduce-malloc-in-v2-servers:
ls-refs: reject unknown arguments
serve: reject commands used as capabilities
serve: reject bogus v2 "command=ls-refs=foo"
docs/protocol-v2: clarify some ls-refs ref-prefix details
ls-refs: ignore very long ref-prefix counts
serve: drop "keys" strvec
serve: provide "receive" function for session-id capability
serve: provide "receive" function for object-format capability
serve: add "receive" method for v2 capabilities table
serve: return capability "value" from get_capability()
serve: rename is_command() to parse_command()
MIDX files are used by default since commit 18e449f86b
(midx: enable core.multiPackIndex by default, 2020-09-25)
Helped-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
An oddball OPTION_ARGUMENT feature has been removed from the
parse-options API.
* ab/retire-option-argument:
parse-options API: remove OPTION_ARGUMENT feature
difftool: use run_command() API in run_file_diff()
difftool: prepare "diff" cmdline in cmd_difftool()
difftool: prepare "struct child_process" in cmd_difftool()
Taking advantage of the CGI interface, http-backend has been
updated to enable protocol v2 automatically when the other side
asks for it.
* jk/http-server-protocol-versions:
docs/protocol-v2: point readers transport config discussion
docs/git: discuss server-side config for GIT_PROTOCOL
docs/http-backend: mention v2 protocol
http-backend: handle HTTP_GIT_PROTOCOL CGI variable
t5551: test v2-to-v0 http protocol fallback
Code clean-up around "git serve".
* ab/serve-cleanup:
upload-pack: document and rename --advertise-refs
serve.[ch]: remove "serve_options", split up --advertise-refs code
{upload,receive}-pack tests: add --advertise-refs tests
serve.c: move version line to advertise_capabilities()
serve: move transfer.advertiseSID check into session_id_advertise()
serve.[ch]: don't pass "struct strvec *keys" to commands
serve: use designated initializers
transport: use designated initializers
transport: rename "fetch" in transport_vtable to "fetch_refs"
serve: mark has_capability() as static
The reachability bitmap file used to be generated only for a single
pack, but now we've learned to generate bitmaps for history that
span across multiple packfiles.
* tb/multi-pack-bitmaps: (29 commits)
pack-bitmap: drop bitmap_index argument from try_partial_reuse()
pack-bitmap: drop repository argument from prepare_midx_bitmap_git()
p5326: perf tests for MIDX bitmaps
p5310: extract full and partial bitmap tests
midx: respect 'GIT_TEST_MULTI_PACK_INDEX_WRITE_BITMAP'
t7700: update to work with MIDX bitmap test knob
t5319: don't write MIDX bitmaps in t5319
t5310: disable GIT_TEST_MULTI_PACK_INDEX_WRITE_BITMAP
t0410: disable GIT_TEST_MULTI_PACK_INDEX_WRITE_BITMAP
t5326: test multi-pack bitmap behavior
t/helper/test-read-midx.c: add --checksum mode
t5310: move some tests to lib-bitmap.sh
pack-bitmap: write multi-pack bitmaps
pack-bitmap: read multi-pack bitmaps
pack-bitmap.c: avoid redundant calls to try_partial_reuse
pack-bitmap.c: introduce 'bitmap_is_preferred_refname()'
pack-bitmap.c: introduce 'nth_bitmap_object_oid()'
pack-bitmap.c: introduce 'bitmap_num_objects()'
midx: avoid opening multiple MIDXs when writing
midx: close linked MIDXs, avoid leaking memory
...
Create "child_ready" event to capture the state of a child process
created in the background.
When a child command is started a "child_start" event is generated in
the Trace2 log. For normal synchronous children, a "child_exit" event
is later generated when the child exits or is terminated. The two events
include information, such as the "child_id" and "pid", to allow post
analysis to match-up the command line and exit status.
When a child is started in the background (and may outlive the parent
process), it is not possible for the parent to emit a "child_exit"
event. Create a new "child_ready" event to indicate whether the
child was successfully started. Also include the "child_id" and "pid"
to allow similar post processing.
This will be used in a later commit with the new "start_bg_command()".
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We've never documented the fact that a client can provide multiple
ref-prefix capabilities. Let's describe the behavior.
We also never discussed the "best effort" nature of the prefixes. The
client side of git.git has always treated them this way, filtering the
result with local patterns. And indeed any client must do this, because
the prefix patterns are not sufficient to express the usual refspecs
(and so for "foo" we ask for "refs/heads/foo", "refs/tags/foo", and so
on).
So this may be considered a change in the spec with respect to client
expectations / requirements, but it's mostly codifying existing
behavior.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* ab/serve-cleanup:
upload-pack: document and rename --advertise-refs
serve.[ch]: remove "serve_options", split up --advertise-refs code
{upload,receive}-pack tests: add --advertise-refs tests
serve.c: move version line to advertise_capabilities()
serve: move transfer.advertiseSID check into session_id_advertise()
serve.[ch]: don't pass "struct strvec *keys" to commands
serve: use designated initializers
transport: use designated initializers
transport: rename "fetch" in transport_vtable to "fetch_refs"
serve: mark has_capability() as static
As was noted in 1a85b49b87 (parse-options: make OPT_ARGUMENT() more
useful, 2019-03-14) there's only ever been one user of the
OPT_ARGUMENT(), that user was added in 20de316e33 (difftool: allow
running outside Git worktrees with --no-index, 2019-03-14).
The OPT_ARGUMENT() feature itself was added way back in
580d5bffde (parse-options: new option type to treat an option-like
parameter as an argument., 2008-03-02), but as discussed in
1a85b49b87 wasn't used until 20de316e33 in 2019.
Now that the preceding commit has migrated this code over to using
"struct strvec" to manage the "args" member of a "struct
child_process", we can just use that directly instead of relying on
OPT_ARGUMENT.
This has a minor change in behavior in that if we'll pass --no-index
we'll now always pass it as the first argument, before we'd pass it in
whatever position the caller did. Preserving this was the real value
of OPT_ARGUMENT(), but as it turns out we didn't need that either. We
can always inject it as the first argument, the other end will parse
it just the same.
Note that we cannot remove the "out" and "cpidx" members of "struct
parse_opt_ctx_t" added in 580d5bffde, while they were introduced with
OPT_ARGUMENT() we since used them for other things.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We recently added tips for server admins to configure various transports
to support v2's GIT_PROTOCOL variable. While the protocol-v2 document is
pretty technical and not of interest to most admins, it may be a
starting point for them to figure out how to turn on v2. Let's put some
pointers from there to the other documentation.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Documentation updates.
* en/merge-strategy-docs:
Update error message and code comment
merge-strategies.txt: add coverage of the `ort` merge strategy
git-rebase.txt: correct out-of-date and misleading text about renames
merge-strategies.txt: fix simple capitalization error
merge-strategies.txt: avoid giving special preference to patience algorithm
merge-strategies.txt: do not imply using copy detection is desired
merge-strategies.txt: update wording for the resolve strategy
Documentation: edit awkward references to `git merge-recursive`
directory-rename-detection.txt: small updates due to merge-ort optimizations
git-rebase.txt: correct antiquated claims about --rebase-merges
trace2 logs learned to show parent process name to see in what
context Git was invoked.
* es/trace2-log-parent-process-name:
tr2: log parent process name
tr2: make process info collection platform-generic
