diff --git a/include/jemalloc/internal/prof_externs.h b/include/jemalloc/internal/prof_externs.h
index e07e69f5..cfb28988 100644
--- a/include/jemalloc/internal/prof_externs.h
+++ b/include/jemalloc/internal/prof_externs.h
@@ -114,50 +114,17 @@ uint64_t tsd_prof_sample_event_wait_get(tsd_t *tsd);
  *
  * Currently only the profiling sampling event needs the lookahead
  * functionality, so we don't yet define general purpose lookahead functions.
- *
- * Surplus is a terminology referring to the amount of bytes beyond what's
- * needed for triggering an event, which can be a useful quantity to have in
- * general when lookahead is being called.
- *
- * This function returns true if allocation of usize would go above the next
- * trigger for prof event, and false otherwise.
- * If function returns true surplus will contain number of bytes beyond that
- * trigger.
  */
 
 JEMALLOC_ALWAYS_INLINE bool
-te_prof_sample_event_lookahead_surplus(
-    tsd_t *tsd, size_t usize, size_t *surplus) {
-	if (surplus != NULL) {
-		/*
-		 * This is a dead store: the surplus will be overwritten before
-		 * any read.  The initialization suppresses compiler warnings.
-		 * Meanwhile, using SIZE_MAX to initialize is good for
-		 * debugging purpose, because a valid surplus value is strictly
-		 * less than usize, which is at most SIZE_MAX.
-		 */
-		*surplus = SIZE_MAX;
-	}
+te_prof_sample_event_lookahead(tsd_t *tsd, size_t usize) {
 	if (unlikely(!tsd_nominal(tsd) || tsd_reentrancy_level_get(tsd) > 0)) {
 		return false;
 	}
 	/* The subtraction is intentionally susceptible to underflow. */
 	uint64_t accumbytes = tsd_thread_allocated_get(tsd) + usize
 	    - tsd_thread_allocated_last_event_get(tsd);
-	uint64_t sample_wait = tsd_prof_sample_event_wait_get(tsd);
-	if (accumbytes < sample_wait) {
-		return false;
-	}
-	assert(accumbytes - sample_wait < (uint64_t)usize);
-	if (surplus != NULL) {
-		*surplus = (size_t)(accumbytes - sample_wait);
-	}
-	return true;
-}
-
-JEMALLOC_ALWAYS_INLINE bool
-te_prof_sample_event_lookahead(tsd_t *tsd, size_t usize) {
-	return te_prof_sample_event_lookahead_surplus(tsd, usize, NULL);
+	return accumbytes >= tsd_prof_sample_event_wait_get(tsd);
 }
 
 extern te_base_cb_t prof_sample_te_handler;