diff options
Diffstat (limited to 'third_party/git/trace2.h')
| -rw-r--r-- | third_party/git/trace2.h | 124 |
1 files changed, 22 insertions, 102 deletions
diff --git a/third_party/git/trace2.h b/third_party/git/trace2.h index e5e81c05332f..050bf3c8c19d 100644 --- a/third_party/git/trace2.h +++ b/third_party/git/trace2.h @@ -1,40 +1,6 @@ #ifndef TRACE2_H #define TRACE2_H -/** - * The Trace2 API can be used to print debug, performance, and telemetry - * information to stderr or a file. The Trace2 feature is inactive unless - * explicitly enabled by enabling one or more Trace2 Targets. - * - * The Trace2 API is intended to replace the existing (Trace1) - * printf-style tracing provided by the existing `GIT_TRACE` and - * `GIT_TRACE_PERFORMANCE` facilities. During initial implementation, - * Trace2 and Trace1 may operate in parallel. - * - * The Trace2 API defines a set of high-level messages with known fields, - * such as (`start`: `argv`) and (`exit`: {`exit-code`, `elapsed-time`}). - * - * Trace2 instrumentation throughout the Git code base sends Trace2 - * messages to the enabled Trace2 Targets. Targets transform these - * messages content into purpose-specific formats and write events to - * their data streams. In this manner, the Trace2 API can drive - * many different types of analysis. - * - * Targets are defined using a VTable allowing easy extension to other - * formats in the future. This might be used to define a binary format, - * for example. - * - * Trace2 is controlled using `trace2.*` config values in the system and - * global config files and `GIT_TRACE2*` environment variables. Trace2 does - * not read from repo local or worktree config files or respect `-c` - * command line config settings. - * - * For more info about: trace2 targets, conventions for public functions and - * macros, trace2 target formats and examples on trace2 API usage refer to - * Documentation/technical/api-trace2.txt - * - */ - struct child_process; struct repository; struct json_writer; @@ -73,12 +39,7 @@ void trace2_initialize_clock(void); /* * Initialize TRACE2 tracing facility if any of the builtin TRACE2 * targets are enabled in the system config or the environment. - * This includes setting up the Trace2 thread local storage (TLS). - * Emits a 'version' message containing the version of git - * and the Trace2 protocol. - * - * This function should be called from `main()` as early as possible in - * the life of the process after essential process initialization. + * Emits a 'version' event. * * Cleanup/Termination is handled automatically by a registered * atexit() routine. @@ -88,7 +49,7 @@ void trace2_initialize_fl(const char *file, int line); #define trace2_initialize() trace2_initialize_fl(__FILE__, __LINE__) /* - * Return 1 if trace2 is enabled (at least one target is active). + * Return true if trace2 is enabled. */ int trace2_is_enabled(void); @@ -153,8 +114,7 @@ void trace2_cmd_mode_fl(const char *file, int line, const char *mode); #define trace2_cmd_mode(sv) trace2_cmd_mode_fl(__FILE__, __LINE__, (sv)) /* - * Emits an "alias" message containing the alias used and the argument - * expansion. + * Emit an 'alias' expansion event. */ void trace2_cmd_alias_fl(const char *file, int line, const char *alias, const char **argv); @@ -163,7 +123,7 @@ void trace2_cmd_alias_fl(const char *file, int line, const char *alias, trace2_cmd_alias_fl(__FILE__, __LINE__, (alias), (argv)) /* - * Emit one or more 'def_param' events for "important" configuration + * Emit one or more 'def_param' events for "interesting" configuration * settings. * * Use the TR2_SYSENV_CFG_PARAM setting to register a comma-separated @@ -184,7 +144,7 @@ void trace2_cmd_list_config_fl(const char *file, int line); /* * Emit a "def_param" event for the given config key/value pair IF - * we consider the key to be "important". + * we consider the key to be "interesting". * * Use this for new/updated config settings created/updated after * trace2_cmd_list_config() is called. @@ -195,34 +155,20 @@ void trace2_cmd_set_config_fl(const char *file, int line, const char *key, #define trace2_cmd_set_config(k, v) \ trace2_cmd_set_config_fl(__FILE__, __LINE__, (k), (v)) -/** - * Emits a "child_start" message containing the "child-id", - * "child-argv", and "child-classification". +/* + * Emit a 'child_start' event prior to spawning a child process. * * Before calling optionally set "cmd->trace2_child_class" to a string * describing the type of the child process. For example, "editor" or * "pager". - * - * This function assigns a unique "child-id" to `cmd->trace2_child_id`. - * This field is used later during the "child_exit" message to associate - * it with the "child_start" message. - * - * This function should be called before spawning the child process. */ void trace2_child_start_fl(const char *file, int line, struct child_process *cmd); #define trace2_child_start(cmd) trace2_child_start_fl(__FILE__, __LINE__, (cmd)) -/** - * Emits a "child_exit" message containing the "child-id", - * the child's elapsed time and exit-code. - * - * The reported elapsed time includes the process creation overhead and - * time spend waiting for it to exit, so it may be slightly longer than - * the time reported by the child itself. - * - * This function should be called after reaping the child process. +/* + * Emit a 'child_exit' event after the child process completes. */ void trace2_child_exit_fl(const char *file, int line, struct child_process *cmd, int child_exit_code); @@ -230,22 +176,21 @@ void trace2_child_exit_fl(const char *file, int line, struct child_process *cmd, #define trace2_child_exit(cmd, code) \ trace2_child_exit_fl(__FILE__, __LINE__, (cmd), (code)) -/** +/* * Emit an 'exec' event prior to calling one of exec(), execv(), * execvp(), and etc. On Unix-derived systems, this will be the * last event emitted for the current process, unless the exec * fails. On Windows, exec() behaves like 'child_start' and a * waitpid(), so additional events may be emitted. * - * Returns a unique "exec-id". This value is used later - * if the exec() fails and a "exec-result" message is necessary. + * Returns the "exec_id". */ int trace2_exec_fl(const char *file, int line, const char *exe, const char **argv); #define trace2_exec(exe, argv) trace2_exec_fl(__FILE__, __LINE__, (exe), (argv)) -/** +/* * Emit an 'exec_result' when possible. On Unix-derived systems, * this should be called after exec() returns (which only happens * when there is an error starting the new process). On Windows, @@ -281,12 +226,11 @@ void trace2_thread_exit_fl(const char *file, int line); #define trace2_thread_exit() trace2_thread_exit_fl(__FILE__, __LINE__) /* - * Emits a "def_param" message containing a key/value pair. + * Emit a 'param' event. * - * This message is intended to report some global aspect of the current - * command, such as a configuration setting or command line switch that - * significantly affects program performance or behavior, such as - * `core.abbrev`, `status.showUntrackedFiles`, or `--no-ahead-behind`. + * Write a "<param> = <value>" pair describing some aspect of the + * run such as an important configuration setting or command line + * option that significantly changes command behavior. */ void trace2_def_param_fl(const char *file, int line, const char *param, const char *value); @@ -299,35 +243,18 @@ void trace2_def_param_fl(const char *file, int line, const char *param, * a trace2-repo-id to be used in subsequent activity events. * * Emits a 'worktree' event for this repo instance. - * - * Region and data messages may refer to this repo-id. - * - * The main/top-level repository will have repo-id value 1 (aka "r1"). - * - * The repo-id field is in anticipation of future in-proc submodule - * repositories. */ void trace2_def_repo_fl(const char *file, int line, struct repository *repo); #define trace2_def_repo(repo) trace2_def_repo_fl(__FILE__, __LINE__, repo) -/** +/* * Emit a 'region_enter' event for <category>.<label> with optional * repo-id and printf message. * - * This function pushes a new region nesting stack level on the current - * thread and starts a clock for the new stack frame. - * - * The `category` field is an arbitrary category name used to classify - * regions by feature area, such as "status" or "index". At this time - * it is only just printed along with the rest of the message. It may - * be used in the future to filter messages. - * - * The `label` field is an arbitrary label used to describe the activity - * being started, such as "read_recursive" or "do_read_index". - * - * The `repo` field, if set, will be used to get the "repo-id", so that - * recursive oerations can be attributed to the correct repository. + * Enter a new nesting level on the current thread and remember the + * current time. This controls the indenting of all subsequent events + * on this thread. */ void trace2_region_enter_fl(const char *file, int line, const char *category, const char *label, const struct repository *repo, ...); @@ -362,17 +289,12 @@ void trace2_region_enter_printf(const char *category, const char *label, /* clang-format on */ #endif -/** +/* * Emit a 'region_leave' event for <category>.<label> with optional * repo-id and printf message. * * Leave current nesting level and report the elapsed time spent * in this nesting level. - * - * The `category`, `label`, and `repo` fields are the same as - * trace2_region_enter_fl. The `category` and `label` do not - * need to match the corresponding "region_enter" message, - * but it makes the data stream easier to understand. */ void trace2_region_leave_fl(const char *file, int line, const char *category, const char *label, const struct repository *repo, ...); @@ -407,12 +329,10 @@ void trace2_region_leave_printf(const char *category, const char *label, /* clang-format on */ #endif -/** +/* * Emit a key-value pair 'data' event of the form <category>.<key> = <value>. * This event implicitly contains information about thread, nesting region, * and optional repo-id. - * This could be used to print the number of files in a directory during - * a multi-threaded recursive tree walk. * * On event-based TRACE2 targets, this generates a 'data' event suitable * for post-processing. On printf-based TRACE2 targets, this is converted |