git/trace2/tr2_tgt_perf.c
Ævar Arnfjörð Bjarmason d3b2159712 run-command API: remove "argv" member, always use "args"
Remove the "argv" member from the run-command API, ever since "args"
was added in c460c0ecdc (run-command: store an optional argv_array,
2014-05-15) being able to provide either "argv" or "args" has led to
some confusion and bugs.

If we hadn't gone in that direction and only had an "argv" our
problems wouldn't have been solved either, as noted in [1] (and in the
documentation amended here) it comes with inherent memory management
issues: The caller would have to hang on to the "argv" until the
run-command API was finished. If the "argv" was an argument to main()
this wasn't an issue, but if it it was manually constructed using the
API might be painful.

We also have a recent report[2] of a user of the API segfaulting,
which is a direct result of it being complex to use. This commit
addresses the root cause of that bug.

This change is larger than I'd like, but there's no easy way to avoid
it that wouldn't involve even more verbose intermediate steps. We use
the "argv" as the source of truth over the "args", so we need to
change all parts of run-command.[ch] itself, as well as the trace2
logging at the same time.

The resulting Windows-specific code in start_command() is a bit nasty,
as we're now assigning to a strvec's "v" member, instead of to our own
"argv". There was a suggestion of some alternate approaches in reply
to an earlier version of this commit[3], but let's leave larger a
larger and needless refactoring of this code for now.

1. http://lore.kernel.org/git/YT6BnnXeAWn8BycF@coredump.intra.peff.net
2. https://lore.kernel.org/git/20211120194048.12125-1-ematsumiya@suse.de/
3. https://lore.kernel.org/git/patch-5.5-ea1011f7473-20211122T153605Z-avarab@gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-11-25 22:15:07 -08:00

583 lines
16 KiB
C

#include "cache.h"
#include "config.h"
#include "run-command.h"
#include "quote.h"
#include "version.h"
#include "json-writer.h"
#include "trace2/tr2_dst.h"
#include "trace2/tr2_sid.h"
#include "trace2/tr2_sysenv.h"
#include "trace2/tr2_tbuf.h"
#include "trace2/tr2_tgt.h"
#include "trace2/tr2_tls.h"
static struct tr2_dst tr2dst_perf = { TR2_SYSENV_PERF, 0, 0, 0, 0 };
/*
* Use TR2_SYSENV_PERF_BRIEF to omit the "<time> <file>:<line>"
* fields from each line written to the builtin performance target.
*
* Unit tests may want to use this to help with testing.
*/
static int tr2env_perf_be_brief;
#define TR2FMT_PERF_FL_WIDTH (28)
#define TR2FMT_PERF_MAX_EVENT_NAME (12)
#define TR2FMT_PERF_REPO_WIDTH (3)
#define TR2FMT_PERF_CATEGORY_WIDTH (12)
#define TR2_INDENT (2)
#define TR2_INDENT_LENGTH(ctx) (((ctx)->nr_open_regions - 1) * TR2_INDENT)
static int fn_init(void)
{
int want = tr2_dst_trace_want(&tr2dst_perf);
int want_brief;
const char *brief;
if (!want)
return want;
brief = tr2_sysenv_get(TR2_SYSENV_PERF_BRIEF);
if (brief && *brief &&
((want_brief = git_parse_maybe_bool(brief)) != -1))
tr2env_perf_be_brief = want_brief;
return want;
}
static void fn_term(void)
{
tr2_dst_trace_disable(&tr2dst_perf);
}
/*
* Format trace line prefix in human-readable classic format for
* the performance target:
* "[<time> [<file>:<line>] <bar>] <nr_parents> <bar>
* <thread_name> <bar> <event_name> <bar> [<repo>] <bar>
* [<elapsed_absolute>] [<elapsed_relative>] <bar>
* [<category>] <bar> [<dots>] "
*/
static void perf_fmt_prepare(const char *event_name,
struct tr2tls_thread_ctx *ctx, const char *file,
int line, const struct repository *repo,
uint64_t *p_us_elapsed_absolute,
uint64_t *p_us_elapsed_relative,
const char *category, struct strbuf *buf)
{
int len;
strbuf_setlen(buf, 0);
if (!tr2env_perf_be_brief) {
struct tr2_tbuf tb_now;
size_t fl_end_col;
tr2_tbuf_local_time(&tb_now);
strbuf_addstr(buf, tb_now.buf);
strbuf_addch(buf, ' ');
fl_end_col = buf->len + TR2FMT_PERF_FL_WIDTH;
if (file && *file) {
struct strbuf buf_fl = STRBUF_INIT;
strbuf_addf(&buf_fl, "%s:%d", file, line);
if (buf_fl.len <= TR2FMT_PERF_FL_WIDTH)
strbuf_addbuf(buf, &buf_fl);
else {
size_t avail = TR2FMT_PERF_FL_WIDTH - 3;
strbuf_addstr(buf, "...");
strbuf_add(buf,
&buf_fl.buf[buf_fl.len - avail],
avail);
}
strbuf_release(&buf_fl);
}
while (buf->len < fl_end_col)
strbuf_addch(buf, ' ');
strbuf_addstr(buf, " | ");
}
strbuf_addf(buf, "d%d | ", tr2_sid_depth());
strbuf_addf(buf, "%-*s | %-*s | ", TR2_MAX_THREAD_NAME,
ctx->thread_name.buf, TR2FMT_PERF_MAX_EVENT_NAME,
event_name);
len = buf->len + TR2FMT_PERF_REPO_WIDTH;
if (repo)
strbuf_addf(buf, "r%d ", repo->trace2_repo_id);
while (buf->len < len)
strbuf_addch(buf, ' ');
strbuf_addstr(buf, " | ");
if (p_us_elapsed_absolute)
strbuf_addf(buf, "%9.6f | ",
((double)(*p_us_elapsed_absolute)) / 1000000.0);
else
strbuf_addf(buf, "%9s | ", " ");
if (p_us_elapsed_relative)
strbuf_addf(buf, "%9.6f | ",
((double)(*p_us_elapsed_relative)) / 1000000.0);
else
strbuf_addf(buf, "%9s | ", " ");
strbuf_addf(buf, "%-*.*s | ", TR2FMT_PERF_CATEGORY_WIDTH,
TR2FMT_PERF_CATEGORY_WIDTH, (category ? category : ""));
if (ctx->nr_open_regions > 0)
strbuf_addchars(buf, '.', TR2_INDENT_LENGTH(ctx));
}
static void perf_io_write_fl(const char *file, int line, const char *event_name,
const struct repository *repo,
uint64_t *p_us_elapsed_absolute,
uint64_t *p_us_elapsed_relative,
const char *category,
const struct strbuf *buf_payload)
{
struct tr2tls_thread_ctx *ctx = tr2tls_get_self();
struct strbuf buf_line = STRBUF_INIT;
perf_fmt_prepare(event_name, ctx, file, line, repo,
p_us_elapsed_absolute, p_us_elapsed_relative, category,
&buf_line);
strbuf_addbuf(&buf_line, buf_payload);
tr2_dst_write_line(&tr2dst_perf, &buf_line);
strbuf_release(&buf_line);
}
static void fn_version_fl(const char *file, int line)
{
const char *event_name = "version";
struct strbuf buf_payload = STRBUF_INIT;
strbuf_addstr(&buf_payload, git_version_string);
perf_io_write_fl(file, line, event_name, NULL, NULL, NULL, NULL,
&buf_payload);
strbuf_release(&buf_payload);
}
static void fn_start_fl(const char *file, int line,
uint64_t us_elapsed_absolute, const char **argv)
{
const char *event_name = "start";
struct strbuf buf_payload = STRBUF_INIT;
sq_append_quote_argv_pretty(&buf_payload, argv);
perf_io_write_fl(file, line, event_name, NULL, &us_elapsed_absolute,
NULL, NULL, &buf_payload);
strbuf_release(&buf_payload);
}
static void fn_exit_fl(const char *file, int line, uint64_t us_elapsed_absolute,
int code)
{
const char *event_name = "exit";
struct strbuf buf_payload = STRBUF_INIT;
strbuf_addf(&buf_payload, "code:%d", code);
perf_io_write_fl(file, line, event_name, NULL, &us_elapsed_absolute,
NULL, NULL, &buf_payload);
strbuf_release(&buf_payload);
}
static void fn_signal(uint64_t us_elapsed_absolute, int signo)
{
const char *event_name = "signal";
struct strbuf buf_payload = STRBUF_INIT;
strbuf_addf(&buf_payload, "signo:%d", signo);
perf_io_write_fl(__FILE__, __LINE__, event_name, NULL,
&us_elapsed_absolute, NULL, NULL, &buf_payload);
strbuf_release(&buf_payload);
}
static void fn_atexit(uint64_t us_elapsed_absolute, int code)
{
const char *event_name = "atexit";
struct strbuf buf_payload = STRBUF_INIT;
strbuf_addf(&buf_payload, "code:%d", code);
perf_io_write_fl(__FILE__, __LINE__, event_name, NULL,
&us_elapsed_absolute, NULL, NULL, &buf_payload);
strbuf_release(&buf_payload);
}
static void maybe_append_string_va(struct strbuf *buf, const char *fmt,
va_list ap)
{
if (fmt && *fmt) {
va_list copy_ap;
va_copy(copy_ap, ap);
strbuf_vaddf(buf, fmt, copy_ap);
va_end(copy_ap);
return;
}
}
static void fn_error_va_fl(const char *file, int line, const char *fmt,
va_list ap)
{
const char *event_name = "error";
struct strbuf buf_payload = STRBUF_INIT;
maybe_append_string_va(&buf_payload, fmt, ap);
perf_io_write_fl(file, line, event_name, NULL, NULL, NULL, NULL,
&buf_payload);
strbuf_release(&buf_payload);
}
static void fn_command_path_fl(const char *file, int line, const char *pathname)
{
const char *event_name = "cmd_path";
struct strbuf buf_payload = STRBUF_INIT;
strbuf_addstr(&buf_payload, pathname);
perf_io_write_fl(file, line, event_name, NULL, NULL, NULL, NULL,
&buf_payload);
strbuf_release(&buf_payload);
}
static void fn_command_ancestry_fl(const char *file, int line, const char **parent_names)
{
const char *event_name = "cmd_ancestry";
struct strbuf buf_payload = STRBUF_INIT;
strbuf_addstr(&buf_payload, "ancestry:[");
/* It's not an argv but the rules are basically the same. */
sq_append_quote_argv_pretty(&buf_payload, parent_names);
strbuf_addch(&buf_payload, ']');
perf_io_write_fl(file, line, event_name, NULL, NULL, NULL, NULL,
&buf_payload);
strbuf_release(&buf_payload);
}
static void fn_command_name_fl(const char *file, int line, const char *name,
const char *hierarchy)
{
const char *event_name = "cmd_name";
struct strbuf buf_payload = STRBUF_INIT;
strbuf_addstr(&buf_payload, name);
if (hierarchy && *hierarchy)
strbuf_addf(&buf_payload, " (%s)", hierarchy);
perf_io_write_fl(file, line, event_name, NULL, NULL, NULL, NULL,
&buf_payload);
strbuf_release(&buf_payload);
}
static void fn_command_mode_fl(const char *file, int line, const char *mode)
{
const char *event_name = "cmd_mode";
struct strbuf buf_payload = STRBUF_INIT;
strbuf_addstr(&buf_payload, mode);
perf_io_write_fl(file, line, event_name, NULL, NULL, NULL, NULL,
&buf_payload);
strbuf_release(&buf_payload);
}
static void fn_alias_fl(const char *file, int line, const char *alias,
const char **argv)
{
const char *event_name = "alias";
struct strbuf buf_payload = STRBUF_INIT;
strbuf_addf(&buf_payload, "alias:%s argv:[", alias);
sq_append_quote_argv_pretty(&buf_payload, argv);
strbuf_addch(&buf_payload, ']');
perf_io_write_fl(file, line, event_name, NULL, NULL, NULL, NULL,
&buf_payload);
strbuf_release(&buf_payload);
}
static void fn_child_start_fl(const char *file, int line,
uint64_t us_elapsed_absolute,
const struct child_process *cmd)
{
const char *event_name = "child_start";
struct strbuf buf_payload = STRBUF_INIT;
if (cmd->trace2_hook_name) {
strbuf_addf(&buf_payload, "[ch%d] class:hook hook:%s",
cmd->trace2_child_id, cmd->trace2_hook_name);
} else {
const char *child_class =
cmd->trace2_child_class ? cmd->trace2_child_class : "?";
strbuf_addf(&buf_payload, "[ch%d] class:%s",
cmd->trace2_child_id, child_class);
}
if (cmd->dir) {
strbuf_addstr(&buf_payload, " cd:");
sq_quote_buf_pretty(&buf_payload, cmd->dir);
}
strbuf_addstr(&buf_payload, " argv:[");
if (cmd->git_cmd) {
strbuf_addstr(&buf_payload, "git");
if (cmd->args.nr)
strbuf_addch(&buf_payload, ' ');
}
sq_append_quote_argv_pretty(&buf_payload, cmd->args.v);
strbuf_addch(&buf_payload, ']');
perf_io_write_fl(file, line, event_name, NULL, &us_elapsed_absolute,
NULL, NULL, &buf_payload);
strbuf_release(&buf_payload);
}
static void fn_child_exit_fl(const char *file, int line,
uint64_t us_elapsed_absolute, int cid, int pid,
int code, uint64_t us_elapsed_child)
{
const char *event_name = "child_exit";
struct strbuf buf_payload = STRBUF_INIT;
strbuf_addf(&buf_payload, "[ch%d] pid:%d code:%d", cid, pid, code);
perf_io_write_fl(file, line, event_name, NULL, &us_elapsed_absolute,
&us_elapsed_child, NULL, &buf_payload);
strbuf_release(&buf_payload);
}
static void fn_child_ready_fl(const char *file, int line,
uint64_t us_elapsed_absolute, int cid, int pid,
const char *ready, uint64_t us_elapsed_child)
{
const char *event_name = "child_ready";
struct strbuf buf_payload = STRBUF_INIT;
strbuf_addf(&buf_payload, "[ch%d] pid:%d ready:%s", cid, pid, ready);
perf_io_write_fl(file, line, event_name, NULL, &us_elapsed_absolute,
&us_elapsed_child, NULL, &buf_payload);
strbuf_release(&buf_payload);
}
static void fn_thread_start_fl(const char *file, int line,
uint64_t us_elapsed_absolute)
{
const char *event_name = "thread_start";
struct strbuf buf_payload = STRBUF_INIT;
perf_io_write_fl(file, line, event_name, NULL, &us_elapsed_absolute,
NULL, NULL, &buf_payload);
strbuf_release(&buf_payload);
}
static void fn_thread_exit_fl(const char *file, int line,
uint64_t us_elapsed_absolute,
uint64_t us_elapsed_thread)
{
const char *event_name = "thread_exit";
struct strbuf buf_payload = STRBUF_INIT;
perf_io_write_fl(file, line, event_name, NULL, &us_elapsed_absolute,
&us_elapsed_thread, NULL, &buf_payload);
strbuf_release(&buf_payload);
}
static void fn_exec_fl(const char *file, int line, uint64_t us_elapsed_absolute,
int exec_id, const char *exe, const char **argv)
{
const char *event_name = "exec";
struct strbuf buf_payload = STRBUF_INIT;
strbuf_addf(&buf_payload, "id:%d ", exec_id);
strbuf_addstr(&buf_payload, "argv:[");
if (exe) {
strbuf_addstr(&buf_payload, exe);
if (argv[0])
strbuf_addch(&buf_payload, ' ');
}
sq_append_quote_argv_pretty(&buf_payload, argv);
strbuf_addch(&buf_payload, ']');
perf_io_write_fl(file, line, event_name, NULL, &us_elapsed_absolute,
NULL, NULL, &buf_payload);
strbuf_release(&buf_payload);
}
static void fn_exec_result_fl(const char *file, int line,
uint64_t us_elapsed_absolute, int exec_id,
int code)
{
const char *event_name = "exec_result";
struct strbuf buf_payload = STRBUF_INIT;
strbuf_addf(&buf_payload, "id:%d code:%d", exec_id, code);
if (code > 0)
strbuf_addf(&buf_payload, " err:%s", strerror(code));
perf_io_write_fl(file, line, event_name, NULL, &us_elapsed_absolute,
NULL, NULL, &buf_payload);
strbuf_release(&buf_payload);
}
static void fn_param_fl(const char *file, int line, const char *param,
const char *value)
{
const char *event_name = "def_param";
struct strbuf buf_payload = STRBUF_INIT;
strbuf_addf(&buf_payload, "%s:%s", param, value);
perf_io_write_fl(file, line, event_name, NULL, NULL, NULL, NULL,
&buf_payload);
strbuf_release(&buf_payload);
}
static void fn_repo_fl(const char *file, int line,
const struct repository *repo)
{
const char *event_name = "def_repo";
struct strbuf buf_payload = STRBUF_INIT;
strbuf_addstr(&buf_payload, "worktree:");
sq_quote_buf_pretty(&buf_payload, repo->worktree);
perf_io_write_fl(file, line, event_name, repo, NULL, NULL, NULL,
&buf_payload);
strbuf_release(&buf_payload);
}
static void fn_region_enter_printf_va_fl(const char *file, int line,
uint64_t us_elapsed_absolute,
const char *category,
const char *label,
const struct repository *repo,
const char *fmt, va_list ap)
{
const char *event_name = "region_enter";
struct strbuf buf_payload = STRBUF_INIT;
if (label)
strbuf_addf(&buf_payload, "label:%s", label);
if (fmt && *fmt) {
strbuf_addch(&buf_payload, ' ');
maybe_append_string_va(&buf_payload, fmt, ap);
}
perf_io_write_fl(file, line, event_name, repo, &us_elapsed_absolute,
NULL, category, &buf_payload);
strbuf_release(&buf_payload);
}
static void fn_region_leave_printf_va_fl(
const char *file, int line, uint64_t us_elapsed_absolute,
uint64_t us_elapsed_region, const char *category, const char *label,
const struct repository *repo, const char *fmt, va_list ap)
{
const char *event_name = "region_leave";
struct strbuf buf_payload = STRBUF_INIT;
if (label)
strbuf_addf(&buf_payload, "label:%s", label);
if (fmt && *fmt) {
strbuf_addch(&buf_payload, ' ' );
maybe_append_string_va(&buf_payload, fmt, ap);
}
perf_io_write_fl(file, line, event_name, repo, &us_elapsed_absolute,
&us_elapsed_region, category, &buf_payload);
strbuf_release(&buf_payload);
}
static void fn_data_fl(const char *file, int line, uint64_t us_elapsed_absolute,
uint64_t us_elapsed_region, const char *category,
const struct repository *repo, const char *key,
const char *value)
{
const char *event_name = "data";
struct strbuf buf_payload = STRBUF_INIT;
strbuf_addf(&buf_payload, "%s:%s", key, value);
perf_io_write_fl(file, line, event_name, repo, &us_elapsed_absolute,
&us_elapsed_region, category, &buf_payload);
strbuf_release(&buf_payload);
}
static void fn_data_json_fl(const char *file, int line,
uint64_t us_elapsed_absolute,
uint64_t us_elapsed_region, const char *category,
const struct repository *repo, const char *key,
const struct json_writer *value)
{
const char *event_name = "data_json";
struct strbuf buf_payload = STRBUF_INIT;
strbuf_addf(&buf_payload, "%s:%s", key, value->json.buf);
perf_io_write_fl(file, line, event_name, repo, &us_elapsed_absolute,
&us_elapsed_region, category, &buf_payload);
strbuf_release(&buf_payload);
}
static void fn_printf_va_fl(const char *file, int line,
uint64_t us_elapsed_absolute, const char *fmt,
va_list ap)
{
const char *event_name = "printf";
struct strbuf buf_payload = STRBUF_INIT;
maybe_append_string_va(&buf_payload, fmt, ap);
perf_io_write_fl(file, line, event_name, NULL, &us_elapsed_absolute,
NULL, NULL, &buf_payload);
strbuf_release(&buf_payload);
}
struct tr2_tgt tr2_tgt_perf = {
&tr2dst_perf,
fn_init,
fn_term,
fn_version_fl,
fn_start_fl,
fn_exit_fl,
fn_signal,
fn_atexit,
fn_error_va_fl,
fn_command_path_fl,
fn_command_ancestry_fl,
fn_command_name_fl,
fn_command_mode_fl,
fn_alias_fl,
fn_child_start_fl,
fn_child_exit_fl,
fn_child_ready_fl,
fn_thread_start_fl,
fn_thread_exit_fl,
fn_exec_fl,
fn_exec_result_fl,
fn_param_fl,
fn_repo_fl,
fn_region_enter_printf_va_fl,
fn_region_leave_printf_va_fl,
fn_data_fl,
fn_data_json_fl,
fn_printf_va_fl,
};