From ab0f1604b4fc563158f142d41f6a3550463d7729 Mon Sep 17 00:00:00 2001
From: Qi Wang <interwq@gwu.edu>
Date: Tue, 28 Sep 2021 15:41:10 -0700
Subject: [PATCH] Delay the atexit call to prof_log_start().

So that atexit() is only done when prof_log is used.
---
 src/prof_log.c | 39 ++++++++++++++++++++++-----------------
 1 file changed, 22 insertions(+), 17 deletions(-)

diff --git a/src/prof_log.c b/src/prof_log.c
index 0f27a128..0632c3b3 100644
--- a/src/prof_log.c
+++ b/src/prof_log.c
@@ -412,6 +412,13 @@ prof_log_dummy_set(bool new_value) {
 	prof_log_dummy = new_value;
 }
 
+/* Used as an atexit function to stop logging on exit. */
+static void
+prof_log_stop_final(void) {
+	tsd_t *tsd = tsd_fetch();
+	prof_log_stop(tsd_tsdn(tsd));
+}
+
 JEMALLOC_COLD
 bool
 prof_log_start(tsdn_t *tsdn, const char *filename) {
@@ -425,6 +432,20 @@ prof_log_start(tsdn_t *tsdn, const char *filename) {
 
 	malloc_mutex_lock(tsdn, &log_mtx);
 
+	static bool prof_log_atexit_called = false;
+	if (!prof_log_atexit_called) {
+		prof_log_atexit_called = true;
+		if (atexit(prof_log_stop_final) != 0) {
+			malloc_write("<jemalloc>: Error in atexit() "
+			    "for logging\n");
+			if (opt_abort) {
+				abort();
+			}
+			ret = true;
+			goto label_done;
+		}
+	}
+
 	if (prof_logging_state != prof_logging_state_stopped) {
 		ret = true;
 	} else if (filename == NULL) {
@@ -442,19 +463,12 @@ prof_log_start(tsdn_t *tsdn, const char *filename) {
 	if (!ret) {
 		nstime_prof_init_update(&log_start_timestamp);
 	}
-
+label_done:
 	malloc_mutex_unlock(tsdn, &log_mtx);
 
 	return ret;
 }
 
-/* Used as an atexit function to stop logging on exit. */
-static void
-prof_log_stop_final(void) {
-	tsd_t *tsd = tsd_fetch();
-	prof_log_stop(tsd_tsdn(tsd));
-}
-
 struct prof_emitter_cb_arg_s {
 	int fd;
 	ssize_t ret;
@@ -697,15 +711,6 @@ prof_log_init(tsd_t *tsd) {
 		prof_log_start(tsd_tsdn(tsd), NULL);
 	}
 
-	if (atexit(prof_log_stop_final) != 0) {
-		malloc_write("<jemalloc>: Error in atexit() "
-			     "for logging\n");
-		if (opt_abort) {
-			abort();
-		}
-		return true;
-	}
-
 	return false;
 }