merge(3p/git): Merge git upstream at v2.26.2 r/808

8 files changed, 214 insertions, 95 deletions

diff --git a/third_party/git/trace2/tr2_dst.c b/third_party/git/trace2/tr2_dst.c
index 5dda0ca1cdb5..ae052a07fe2e 100644
--- a/third_party/git/trace2/tr2_dst.c
+++ b/third_party/git/trace2/tr2_dst.c
@@ -8,6 +8,19 @@
  */
 #define MAX_AUTO_ATTEMPTS 10
 
+/*
+ * Sentinel file used to detect when we should discard new traces to avoid
+ * writing too many trace files to a directory.
+ */
+#define DISCARD_SENTINEL_NAME "git-trace2-discard"
+
+/*
+ * When set to zero, disables directory file count checks. Otherwise, controls
+ * how many files we can write to a directory before entering discard mode.
+ * This can be overridden via the TR2_SYSENV_MAX_FILES setting.
+ */
+static int tr2env_max_files = 0;
+
 static int tr2_dst_want_warning(void)
 {
 	static int tr2env_dst_debug = -1;
@@ -32,9 +45,75 @@ void tr2_dst_trace_disable(struct tr2_dst *dst)
 	dst->need_close = 0;
 }
 
+/*
+ * Check to make sure we're not overloading the target directory with too many
+ * files. First get the threshold (if present) from the config or envvar. If
+ * it's zero or unset, disable this check. Next check for the presence of a
+ * sentinel file, then check file count.
+ *
+ * Returns 0 if tracing should proceed as normal. Returns 1 if the sentinel file
+ * already exists, which means tracing should be disabled. Returns -1 if there
+ * are too many files but there was no sentinel file, which means we have
+ * created and should write traces to the sentinel file.
+ *
+ * We expect that some trace processing system is gradually collecting files
+ * from the target directory; after it removes the sentinel file we'll start
+ * writing traces again.
+ */
+static int tr2_dst_too_many_files(struct tr2_dst *dst, const char *tgt_prefix)
+{
+	int file_count = 0, max_files = 0, ret = 0;
+	const char *max_files_var;
+	DIR *dirp;
+	struct strbuf path = STRBUF_INIT, sentinel_path = STRBUF_INIT;
+	struct stat statbuf;
+
+	/* Get the config or envvar and decide if we should continue this check */
+	max_files_var = tr2_sysenv_get(TR2_SYSENV_MAX_FILES);
+	if (max_files_var && *max_files_var && ((max_files = atoi(max_files_var)) >= 0))
+		tr2env_max_files = max_files;
+
+	if (!tr2env_max_files) {
+		ret = 0;
+		goto cleanup;
+	}
+
+	strbuf_addstr(&path, tgt_prefix);
+	if (!is_dir_sep(path.buf[path.len - 1])) {
+		strbuf_addch(&path, '/');
+	}
+
+	/* check sentinel */
+	strbuf_addbuf(&sentinel_path, &path);
+	strbuf_addstr(&sentinel_path, DISCARD_SENTINEL_NAME);
+	if (!stat(sentinel_path.buf, &statbuf)) {
+		ret = 1;
+		goto cleanup;
+	}
+
+	/* check file count */
+	dirp = opendir(path.buf);
+	while (file_count < tr2env_max_files && dirp && readdir(dirp))
+		file_count++;
+	if (dirp)
+		closedir(dirp);
+
+	if (file_count >= tr2env_max_files) {
+		dst->too_many_files = 1;
+		dst->fd = open(sentinel_path.buf, O_WRONLY | O_CREAT | O_EXCL, 0666);
+		ret = -1;
+		goto cleanup;
+	}
+
+cleanup:
+	strbuf_release(&path);
+	strbuf_release(&sentinel_path);
+	return ret;
+}
+
 static int tr2_dst_try_auto_path(struct tr2_dst *dst, const char *tgt_prefix)
 {
-	int fd;
+	int too_many_files;
 	const char *last_slash, *sid = tr2_sid_get();
 	struct strbuf path = STRBUF_INIT;
 	size_t base_path_len;
@@ -50,18 +129,29 @@ static int tr2_dst_try_auto_path(struct tr2_dst *dst, const char *tgt_prefix)
 	strbuf_addstr(&path, sid);
 	base_path_len = path.len;
 
-	for (attempt_count = 0; attempt_count < MAX_AUTO_ATTEMPTS; attempt_count++) {
-		if (attempt_count > 0) {
-			strbuf_setlen(&path, base_path_len);
-			strbuf_addf(&path, ".%d", attempt_count);
+	too_many_files = tr2_dst_too_many_files(dst, tgt_prefix);
+	if (!too_many_files) {
+		for (attempt_count = 0; attempt_count < MAX_AUTO_ATTEMPTS; attempt_count++) {
+			if (attempt_count > 0) {
+				strbuf_setlen(&path, base_path_len);
+				strbuf_addf(&path, ".%d", attempt_count);
+			}
+
+			dst->fd = open(path.buf, O_WRONLY | O_CREAT | O_EXCL, 0666);
+			if (dst->fd != -1)
+				break;
 		}
-
-		fd = open(path.buf, O_WRONLY | O_CREAT | O_EXCL, 0666);
-		if (fd != -1)
-			break;
+	} else if (too_many_files == 1) {
+		strbuf_release(&path);
+		if (tr2_dst_want_warning())
+			warning("trace2: not opening %s trace file due to too "
+				"many files in target directory %s",
+				tr2_sysenv_display_name(dst->sysenv_var),
+				tgt_prefix);
+		return 0;
 	}
 
-	if (fd == -1) {
+	if (dst->fd == -1) {
 		if (tr2_dst_want_warning())
 			warning("trace2: could not open '%.*s' for '%s' tracing: %s",
 				(int) base_path_len, path.buf,
@@ -75,7 +165,6 @@ static int tr2_dst_try_auto_path(struct tr2_dst *dst, const char *tgt_prefix)
 
 	strbuf_release(&path);
 
-	dst->fd = fd;
 	dst->need_close = 1;
 	dst->initialized = 1;
 
@@ -215,13 +304,8 @@ connected:
 static void tr2_dst_malformed_warning(struct tr2_dst *dst,
 				      const char *tgt_value)
 {
-	struct strbuf buf = STRBUF_INIT;
-
-	strbuf_addf(&buf, "trace2: unknown value for '%s': '%s'",
-		    tr2_sysenv_display_name(dst->sysenv_var), tgt_value);
-	warning("%s", buf.buf);
-
-	strbuf_release(&buf);
+	warning("trace2: unknown value for '%s': '%s'",
+		tr2_sysenv_display_name(dst->sysenv_var), tgt_value);
 }
 
 int tr2_dst_get_trace_fd(struct tr2_dst *dst)
diff --git a/third_party/git/trace2/tr2_dst.h b/third_party/git/trace2/tr2_dst.h
index 3adf3bac139b..b1a8c144e073 100644
--- a/third_party/git/trace2/tr2_dst.h
+++ b/third_party/git/trace2/tr2_dst.h
@@ -9,6 +9,7 @@ struct tr2_dst {
 	int fd;
 	unsigned int initialized : 1;
 	unsigned int need_close : 1;
+	unsigned int too_many_files : 1;
 };
 
 /*
diff --git a/third_party/git/trace2/tr2_sid.c b/third_party/git/trace2/tr2_sid.c
index 6948fd41086f..dc6e75ef1315 100644
--- a/third_party/git/trace2/tr2_sid.c
+++ b/third_party/git/trace2/tr2_sid.c
@@ -19,7 +19,7 @@ static int tr2sid_nr_git_parents;
  *    "H<first_8_chars_of_sha1_of_hostname>"
  *    "Localhost" when no hostname.
  *
- * where <process> is a 9 character string containing the least signifcant
+ * where <process> is a 9 character string containing the least significant
  * 32 bits in the process-id.
  *    "P<pid>"
  * (This is an abribrary choice.  On most systems pid_t is a 32 bit value,
diff --git a/third_party/git/trace2/tr2_sysenv.c b/third_party/git/trace2/tr2_sysenv.c
index 5958cfc424b5..3c3792eca2e2 100644
--- a/third_party/git/trace2/tr2_sysenv.c
+++ b/third_party/git/trace2/tr2_sysenv.c
@@ -49,6 +49,9 @@ static struct tr2_sysenv_entry tr2_sysenv_settings[] = {
 				       "trace2.perftarget" },
 	[TR2_SYSENV_PERF_BRIEF]    = { "GIT_TRACE2_PERF_BRIEF",
 				       "trace2.perfbrief" },
+
+	[TR2_SYSENV_MAX_FILES]     = { "GIT_TRACE2_MAX_FILES",
+				       "trace2.maxfiles" },
 };
 /* clang-format on */
 
diff --git a/third_party/git/trace2/tr2_sysenv.h b/third_party/git/trace2/tr2_sysenv.h
index 8dd82a7a56bb..d4364a7b85a5 100644
--- a/third_party/git/trace2/tr2_sysenv.h
+++ b/third_party/git/trace2/tr2_sysenv.h
@@ -24,6 +24,8 @@ enum tr2_sysenv_variable {
 	TR2_SYSENV_PERF,
 	TR2_SYSENV_PERF_BRIEF,
 
+	TR2_SYSENV_MAX_FILES,
+
 	TR2_SYSENV_MUST_BE_LAST
 };
 
diff --git a/third_party/git/trace2/tr2_tgt_event.c b/third_party/git/trace2/tr2_tgt_event.c
index c2852d1bd2bd..6353e8ad9156 100644
--- a/third_party/git/trace2/tr2_tgt_event.c
+++ b/third_party/git/trace2/tr2_tgt_event.c
@@ -10,16 +10,17 @@
 #include "trace2/tr2_tgt.h"
 #include "trace2/tr2_tls.h"
 
-static struct tr2_dst tr2dst_event = { TR2_SYSENV_EVENT, 0, 0, 0 };
+static struct tr2_dst tr2dst_event = { TR2_SYSENV_EVENT, 0, 0, 0, 0 };
 
 /*
- * The version number of the JSON data generated by the EVENT target
- * in this source file.  Update this if you make a significant change
- * to the JSON fields or message structure.  You probably do not need
- * to update this if you just add another call to one of the existing
- * TRACE2 API methods.
+ * The version number of the JSON data generated by the EVENT target in this
+ * source file. The version should be incremented if new event types are added,
+ * if existing fields are removed, or if there are significant changes in
+ * interpretation of existing events or fields. Smaller changes, such as adding
+ * a new field to an existing event, do not require an increment to the EVENT
+ * format version.
  */
-#define TR2_EVENT_VERSION "1"
+#define TR2_EVENT_VERSION "2"
 
 /*
  * Region nesting limit for messages written to the event target.
@@ -107,6 +108,19 @@ static void event_fmt_prepare(const char *event_name, const char *file,
 		jw_object_intmax(jw, "repo", repo->trace2_repo_id);
 }
 
+static void fn_too_many_files_fl(const char *file, int line)
+{
+	const char *event_name = "too_many_files";
+	struct json_writer jw = JSON_WRITER_INIT;
+
+	jw_object_begin(&jw, 0);
+	event_fmt_prepare(event_name, file, line, NULL, &jw);
+	jw_end(&jw);
+
+	tr2_dst_write_line(&tr2dst_event, &jw.json);
+	jw_release(&jw);
+}
+
 static void fn_version_fl(const char *file, int line)
 {
 	const char *event_name = "version";
@@ -120,6 +134,9 @@ static void fn_version_fl(const char *file, int line)
 
 	tr2_dst_write_line(&tr2dst_event, &jw.json);
 	jw_release(&jw);
+
+	if (tr2dst_event.too_many_files)
+		fn_too_many_files_fl(file, line);
 }
 
 static void fn_start_fl(const char *file, int line,
@@ -205,11 +222,6 @@ static void maybe_add_string_va(struct json_writer *jw, const char *field_name,
 		strbuf_release(&buf);
 		return;
 	}
-
-	if (fmt && *fmt) {
-		jw_object_string(jw, field_name, fmt);
-		return;
-	}
 }
 
 static void fn_error_va_fl(const char *file, int line, const char *fmt,
diff --git a/third_party/git/trace2/tr2_tgt_normal.c b/third_party/git/trace2/tr2_tgt_normal.c
index 00b116d797c8..31b602c171fc 100644
--- a/third_party/git/trace2/tr2_tgt_normal.c
+++ b/third_party/git/trace2/tr2_tgt_normal.c
@@ -9,7 +9,7 @@
 #include "trace2/tr2_tgt.h"
 #include "trace2/tr2_tls.h"
 
-static struct tr2_dst tr2dst_normal = { TR2_SYSENV_NORMAL, 0, 0, 0 };
+static struct tr2_dst tr2dst_normal = { TR2_SYSENV_NORMAL, 0, 0, 0, 0 };
 
 /*
  * Use the TR2_SYSENV_NORMAL_BRIEF setting to omit the "<time> <file>:<line>"
@@ -87,7 +87,7 @@ static void fn_start_fl(const char *file, int line,
 	struct strbuf buf_payload = STRBUF_INIT;
 
 	strbuf_addstr(&buf_payload, "start ");
-	sq_quote_argv_pretty(&buf_payload, argv);
+	sq_append_quote_argv_pretty(&buf_payload, argv);
 	normal_io_write_fl(file, line, &buf_payload);
 	strbuf_release(&buf_payload);
 }
@@ -135,11 +135,6 @@ static void maybe_append_string_va(struct strbuf *buf, const char *fmt,
 		va_end(copy_ap);
 		return;
 	}
-
-	if (fmt && *fmt) {
-		strbuf_addstr(buf, fmt);
-		return;
-	}
 }
 
 static void fn_error_va_fl(const char *file, int line, const char *fmt,
@@ -147,8 +142,11 @@ static void fn_error_va_fl(const char *file, int line, const char *fmt,
 {
 	struct strbuf buf_payload = STRBUF_INIT;
 
-	strbuf_addstr(&buf_payload, "error ");
-	maybe_append_string_va(&buf_payload, fmt, ap);
+	strbuf_addstr(&buf_payload, "error");
+	if (fmt && *fmt) {
+		strbuf_addch(&buf_payload, ' ');
+		maybe_append_string_va(&buf_payload, fmt, ap);
+	}
 	normal_io_write_fl(file, line, &buf_payload);
 	strbuf_release(&buf_payload);
 }
@@ -188,8 +186,8 @@ static void fn_alias_fl(const char *file, int line, const char *alias,
 {
 	struct strbuf buf_payload = STRBUF_INIT;
 
-	strbuf_addf(&buf_payload, "alias %s ->", alias);
-	sq_quote_argv_pretty(&buf_payload, argv);
+	strbuf_addf(&buf_payload, "alias %s -> ", alias);
+	sq_append_quote_argv_pretty(&buf_payload, argv);
 	normal_io_write_fl(file, line, &buf_payload);
 	strbuf_release(&buf_payload);
 }
@@ -200,12 +198,12 @@ static void fn_child_start_fl(const char *file, int line,
 {
 	struct strbuf buf_payload = STRBUF_INIT;
 
-	strbuf_addf(&buf_payload, "child_start[%d] ", cmd->trace2_child_id);
+	strbuf_addf(&buf_payload, "child_start[%d]", cmd->trace2_child_id);
 
 	if (cmd->dir) {
-		strbuf_addstr(&buf_payload, " cd");
+		strbuf_addstr(&buf_payload, " cd ");
 		sq_quote_buf_pretty(&buf_payload, cmd->dir);
-		strbuf_addstr(&buf_payload, "; ");
+		strbuf_addstr(&buf_payload, ";");
 	}
 
 	/*
@@ -213,9 +211,10 @@ static void fn_child_start_fl(const char *file, int line,
 	 * See trace_add_env() in run-command.c as used by original trace.c
 	 */
 
+	strbuf_addch(&buf_payload, ' ');
 	if (cmd->git_cmd)
-		strbuf_addstr(&buf_payload, "git");
-	sq_quote_argv_pretty(&buf_payload, cmd->argv);
+		strbuf_addstr(&buf_payload, "git ");
+	sq_append_quote_argv_pretty(&buf_payload, cmd->argv);
 
 	normal_io_write_fl(file, line, &buf_payload);
 	strbuf_release(&buf_payload);
@@ -240,9 +239,11 @@ static void fn_exec_fl(const char *file, int line, uint64_t us_elapsed_absolute,
 	struct strbuf buf_payload = STRBUF_INIT;
 
 	strbuf_addf(&buf_payload, "exec[%d] ", exec_id);
-	if (exe)
+	if (exe) {
 		strbuf_addstr(&buf_payload, exe);
-	sq_quote_argv_pretty(&buf_payload, argv);
+		strbuf_addch(&buf_payload, ' ');
+	}
+	sq_append_quote_argv_pretty(&buf_payload, argv);
 	normal_io_write_fl(file, line, &buf_payload);
 	strbuf_release(&buf_payload);
 }
diff --git a/third_party/git/trace2/tr2_tgt_perf.c b/third_party/git/trace2/tr2_tgt_perf.c
index ea0cbbe13ee0..a8018f18cc87 100644
--- a/third_party/git/trace2/tr2_tgt_perf.c
+++ b/third_party/git/trace2/tr2_tgt_perf.c
@@ -11,7 +11,7 @@
 #include "trace2/tr2_tgt.h"
 #include "trace2/tr2_tls.h"
 
-static struct tr2_dst tr2dst_perf = { TR2_SYSENV_PERF, 0, 0, 0 };
+static struct tr2_dst tr2dst_perf = { TR2_SYSENV_PERF, 0, 0, 0, 0 };
 
 /*
  * Use TR2_SYSENV_PERF_BRIEF to omit the "<time> <file>:<line>"
@@ -21,17 +21,14 @@ static struct tr2_dst tr2dst_perf = { TR2_SYSENV_PERF, 0, 0, 0 };
  */
 static int tr2env_perf_be_brief;
 
-#define TR2FMT_PERF_FL_WIDTH (50)
+#define TR2FMT_PERF_FL_WIDTH (28)
 #define TR2FMT_PERF_MAX_EVENT_NAME (12)
-#define TR2FMT_PERF_REPO_WIDTH (4)
-#define TR2FMT_PERF_CATEGORY_WIDTH (10)
+#define TR2FMT_PERF_REPO_WIDTH (3)
+#define TR2FMT_PERF_CATEGORY_WIDTH (12)
 
-#define TR2_DOTS_BUFFER_SIZE (100)
 #define TR2_INDENT (2)
 #define TR2_INDENT_LENGTH(ctx) (((ctx)->nr_open_regions - 1) * TR2_INDENT)
 
-static struct strbuf dots = STRBUF_INIT;
-
 static int fn_init(void)
 {
 	int want = tr2_dst_trace_want(&tr2dst_perf);
@@ -41,8 +38,6 @@ static int fn_init(void)
 	if (!want)
 		return want;
 
-	strbuf_addchars(&dots, '.', TR2_DOTS_BUFFER_SIZE);
-
 	brief = tr2_sysenv_get(TR2_SYSENV_PERF_BRIEF);
 	if (brief && *brief &&
 	    ((want_brief = git_parse_maybe_bool(brief)) != -1))
@@ -54,8 +49,6 @@ static int fn_init(void)
 static void fn_term(void)
 {
 	tr2_dst_trace_disable(&tr2dst_perf);
-
-	strbuf_release(&dots);
 }
 
 /*
@@ -79,17 +72,36 @@ static void perf_fmt_prepare(const char *event_name,
 
 	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, ' ');
 
-		if (file && *file)
-			strbuf_addf(buf, "%s:%d ", file, line);
-		while (buf->len < TR2FMT_PERF_FL_WIDTH)
+		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_addstr(buf, " | ");
 	}
 
 	strbuf_addf(buf, "d%d | ", tr2_sid_depth());
@@ -102,7 +114,7 @@ static void perf_fmt_prepare(const char *event_name,
 		strbuf_addf(buf, "r%d ", repo->trace2_repo_id);
 	while (buf->len < len)
 		strbuf_addch(buf, ' ');
-	strbuf_addstr(buf, "| ");
+	strbuf_addstr(buf, " | ");
 
 	if (p_us_elapsed_absolute)
 		strbuf_addf(buf, "%9.6f | ",
@@ -116,17 +128,11 @@ static void perf_fmt_prepare(const char *event_name,
 	else
 		strbuf_addf(buf, "%9s | ", " ");
 
-	strbuf_addf(buf, "%-*s | ", TR2FMT_PERF_CATEGORY_WIDTH,
-		    (category ? category : ""));
+	strbuf_addf(buf, "%-*.*s | ", TR2FMT_PERF_CATEGORY_WIDTH,
+		    TR2FMT_PERF_CATEGORY_WIDTH, (category ? category : ""));
 
-	if (ctx->nr_open_regions > 0) {
-		int len_indent = TR2_INDENT_LENGTH(ctx);
-		while (len_indent > dots.len) {
-			strbuf_addbuf(buf, &dots);
-			len_indent -= dots.len;
-		}
-		strbuf_addf(buf, "%.*s", len_indent, dots.buf);
-	}
+	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,
@@ -165,7 +171,7 @@ static void fn_start_fl(const char *file, int line,
 	const char *event_name = "start";
 	struct strbuf buf_payload = STRBUF_INIT;
 
-	sq_quote_argv_pretty(&buf_payload, argv);
+	sq_append_quote_argv_pretty(&buf_payload, argv);
 
 	perf_io_write_fl(file, line, event_name, NULL, &us_elapsed_absolute,
 			 NULL, NULL, &buf_payload);
@@ -220,11 +226,6 @@ static void maybe_append_string_va(struct strbuf *buf, const char *fmt,
 		va_end(copy_ap);
 		return;
 	}
-
-	if (fmt && *fmt) {
-		strbuf_addstr(buf, fmt);
-		return;
-	}
 }
 
 static void fn_error_va_fl(const char *file, int line, const char *fmt,
@@ -285,8 +286,9 @@ static void fn_alias_fl(const char *file, int line, const char *alias,
 	const char *event_name = "alias";
 	struct strbuf buf_payload = STRBUF_INIT;
 
-	strbuf_addf(&buf_payload, "alias:%s argv:", alias);
-	sq_quote_argv_pretty(&buf_payload, argv);
+	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);
@@ -315,10 +317,14 @@ static void fn_child_start_fl(const char *file, int line,
 		sq_quote_buf_pretty(&buf_payload, cmd->dir);
 	}
 
-	strbuf_addstr(&buf_payload, " argv:");
-	if (cmd->git_cmd)
-		strbuf_addstr(&buf_payload, " git");
-	sq_quote_argv_pretty(&buf_payload, cmd->argv);
+	strbuf_addstr(&buf_payload, " argv:[");
+	if (cmd->git_cmd) {
+		strbuf_addstr(&buf_payload, "git");
+		if (cmd->argv[0])
+			strbuf_addch(&buf_payload, ' ');
+	}
+	sq_append_quote_argv_pretty(&buf_payload, cmd->argv);
+	strbuf_addch(&buf_payload, ']');
 
 	perf_io_write_fl(file, line, event_name, NULL, &us_elapsed_absolute,
 			 NULL, NULL, &buf_payload);
@@ -369,10 +375,14 @@ static void fn_exec_fl(const char *file, int line, uint64_t us_elapsed_absolute,
 	struct strbuf buf_payload = STRBUF_INIT;
 
 	strbuf_addf(&buf_payload, "id:%d ", exec_id);
-	strbuf_addstr(&buf_payload, "argv:");
-	if (exe)
-		strbuf_addf(&buf_payload, " %s", exe);
-	sq_quote_argv_pretty(&buf_payload, argv);
+	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);
@@ -433,8 +443,11 @@ static void fn_region_enter_printf_va_fl(const char *file, int line,
 	struct strbuf buf_payload = STRBUF_INIT;
 
 	if (label)
-		strbuf_addf(&buf_payload, "label:%s ", label);
-	maybe_append_string_va(&buf_payload, fmt, ap);
+		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);
@@ -450,8 +463,11 @@ static void fn_region_leave_printf_va_fl(
 	struct strbuf buf_payload = STRBUF_INIT;
 
 	if (label)
-		strbuf_addf(&buf_payload, "label:%s ", label);
-	maybe_append_string_va(&buf_payload, fmt, ap);
+		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);