2022-03-17 03:22:55

by Jiri Olsa

[permalink] [raw]
Subject: [PATCHv3 bpf-next 02/13] kallsyms: Skip the name search for empty string

When kallsyms_lookup_name is called with empty string,
it will do futile search for it through all the symbols.

Skipping the search for empty string.

Signed-off-by: Jiri Olsa <[email protected]>
---
kernel/kallsyms.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index 951c93216fc4..79f2eb617a62 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -212,6 +212,10 @@ unsigned long kallsyms_lookup_name(const char *name)
unsigned long i;
unsigned int off;

+ /* Skip the search for empty string. */
+ if (!*name)
+ return 0;
+
for (i = 0, off = 0; i < kallsyms_num_syms; i++) {
off = kallsyms_expand_symbol(off, namebuf, ARRAY_SIZE(namebuf));

--
2.35.1