[PATCH v3] ftrace: simplify ftrace hash lookup code in clear_func_from_hash()

From: Changbin Du
Date: Tue Sep 10 2019 - 10:33:51 EST


Function ftrace_lookup_ip() will check empty hash table. So we don't
need extra check outside.

Signed-off-by: Changbin Du <changbin.du@xxxxxxxxx>

---
v3: only keep the change in function clear_func_from_hash().
v2: fix incorrect code remove.
---
kernel/trace/ftrace.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index f9821a3374e9..c4cc048eb594 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -6036,11 +6036,7 @@ clear_func_from_hash(struct ftrace_init_func *func, struct ftrace_hash *hash)
{
struct ftrace_func_entry *entry;

- if (ftrace_hash_empty(hash))
- return;
-
- entry = __ftrace_lookup_ip(hash, func->ip);
-
+ entry = ftrace_lookup_ip(hash, func->ip);
/*
* Do not allow this rec to match again.
* Yeah, it may waste some memory, but will be removed
--
2.20.1