diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c
index a509aa8433a1c7dcac1998025b95258207973c24..577e600c8eb15a66cb50580b0c6361060147894a 100644
--- a/tools/perf/util/dwarf-aux.c
+++ b/tools/perf/util/dwarf-aux.c
@@ -915,7 +915,7 @@ int die_get_typename(Dwarf_Die *vr_die, struct strbuf *buf)
 		tmp = "*";
 	else if (tag == DW_TAG_subroutine_type) {
 		/* Function pointer */
-		strbuf_addf(buf, "(function_type)");
+		strbuf_add(buf, "(function_type)", 15);
 		return 0;
 	} else {
 		if (!dwarf_diename(&type))
@@ -932,7 +932,7 @@ int die_get_typename(Dwarf_Die *vr_die, struct strbuf *buf)
 	}
 	ret = die_get_typename(&type, buf);
 	if (ret == 0)
-		strbuf_addf(buf, "%s", tmp);
+		strbuf_addstr(buf, tmp);
 
 	return ret;
 }
@@ -951,7 +951,7 @@ int die_get_varname(Dwarf_Die *vr_die, struct strbuf *buf)
 	ret = die_get_typename(vr_die, buf);
 	if (ret < 0) {
 		pr_debug("Failed to get type, make it unknown.\n");
-		strbuf_addf(buf, "(unknown_type)");
+		strbuf_add(buf, " (unknown_type)", 14);
 	}
 
 	strbuf_addf(buf, "\t%s", dwarf_diename(vr_die));
@@ -1013,7 +1013,7 @@ static int die_get_var_innermost_scope(Dwarf_Die *sp_die, Dwarf_Die *vr_die,
 	}
 
 	if (!first)
-		strbuf_addf(buf, "]>");
+		strbuf_add(buf, "]>", 2);
 
 out:
 	free(scopes);
@@ -1076,7 +1076,7 @@ int die_get_var_range(Dwarf_Die *sp_die, Dwarf_Die *vr_die, struct strbuf *buf)
 	}
 
 	if (!first)
-		strbuf_addf(buf, "]>");
+		strbuf_add(buf, "]>", 2);
 
 	return ret;
 }
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 93996ec4bbe34f9d380e93a2cb2e8f27c05dede6..8319fbb0863618f9d5bff52f17559dc2ab23e2b7 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -2179,7 +2179,7 @@ static int perf_probe_event__sprintf(const char *group, const char *event,
 		strbuf_addf(result, " in %s", module);
 
 	if (pev->nargs > 0) {
-		strbuf_addstr(result, " with");
+		strbuf_add(result, " with", 5);
 		for (i = 0; i < pev->nargs; i++) {
 			ret = synthesize_perf_probe_arg(&pev->args[i],
 							buf, 128);
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index 4ce5c5e18f48cd43777d2eb9c77aea35944440b8..b3bd0fba023795fce8e862cd0236914125e8d072 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -1314,18 +1314,18 @@ static int collect_variables_cb(Dwarf_Die *die_mem, void *data)
 			if (probe_conf.show_location_range) {
 				if (!externs) {
 					if (ret)
-						strbuf_addf(&buf, "[INV]\t");
+						strbuf_add(&buf, "[INV]\t", 6);
 					else
-						strbuf_addf(&buf, "[VAL]\t");
+						strbuf_add(&buf, "[VAL]\t", 6);
 				} else
-					strbuf_addf(&buf, "[EXT]\t");
+					strbuf_add(&buf, "[EXT]\t", 6);
 			}
 
 			ret2 = die_get_varname(die_mem, &buf);
 
 			if (!ret2 && probe_conf.show_location_range &&
 				!externs) {
-				strbuf_addf(&buf, "\t");
+				strbuf_addch(&buf, '\t');
 				ret2 = die_get_var_range(&af->pf.sp_die,
 							die_mem, &buf);
 			}