git/Documentation/technical/api-trace2.txt, branch v2.37.4

usage.c: add a non-fatal bug() function to go with BUG()

2022-06-02T19:51:35Z

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 Signed-off-by: Junio C Hamano

trace2 docs: add missing full stop

2022-05-04T17:31:05Z

Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano

trace2 docs: clarify what `varargs` is all about

2022-05-04T17:31:05Z

Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano

trace2 docs: fix a JSON formatted example

2022-05-04T17:31:04Z

The example was not in valid JSON format due to a duplicate key "sid". Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano

trace2 docs: surround more terms in backticks

2022-05-04T17:31:04Z

Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano

trace2 docs: "printf" is not an English word

2022-05-04T17:31:04Z

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 Signed-off-by: Junio C Hamano

trace2 docs: a couple of grammar fixes

2022-05-04T17:31:04Z

Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano

trace2: increment event format version

2021-11-11T23:01:04Z

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 Signed-off-by: Junio C Hamano

trace2: add trace2_child_ready() to report on background children

2021-09-20T15:57:58Z

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 Signed-off-by: Junio C Hamano

Merge branch 'es/trace2-log-parent-process-name'

2021-08-24T22:32:40Z

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