Move code that checks on valid direct ip into separate
check_direct_entry function. It will be used in following
patches, there's no functional change.
Signed-off-by: Jiri Olsa <jo...@kernel.org>
---
kernel/trace/ftrace.c | 55 +++++++++++++++++++++++++------------------
1 file changed, 32 insertions(+), 23 deletions(-)
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 8185f7240095..27e9210073d3 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -5025,6 +5025,36 @@ struct ftrace_direct_func
*ftrace_find_direct_func(unsigned long addr)
return NULL;
}
+static int check_direct_ip(unsigned long ip)
+{
+ struct dyn_ftrace *rec;
+
+ /* See if there's a direct function at @ip already */
+ if (ftrace_find_rec_direct(ip))
+ return -EBUSY;
+
+ rec = lookup_rec(ip, ip);
+ if (!rec)
+ return -ENODEV;
+
+ /*
+ * Check if the rec says it has a direct call but we didn't
+ * find one earlier?
+ */
+ if (WARN_ON(rec->flags & FTRACE_FL_DIRECT))
+ return -ENODEV;
+
+ /* Make sure the ip points to the exact record */
+ if (ip != rec->ip) {
+ ip = rec->ip;
+ /* Need to check this ip for a direct. */
+ if (ftrace_find_rec_direct(ip))
+ return -EBUSY;
+ }
+
+ return 0;
+}
+
/**
* register_ftrace_direct - Call a custom trampoline directly
* @ip: The address of the nop at the beginning of a function
@@ -5047,35 +5077,14 @@ int register_ftrace_direct(unsigned long ip, unsigned
long addr)
struct ftrace_direct_func *direct;
struct ftrace_func_entry *entry;
struct ftrace_hash *free_hash = NULL;
- struct dyn_ftrace *rec;
int ret = -EBUSY;
mutex_lock(&direct_mutex);
- /* See if there's a direct function at @ip already */
- if (ftrace_find_rec_direct(ip))
- goto out_unlock;
-
- ret = -ENODEV;
- rec = lookup_rec(ip, ip);
- if (!rec)
- goto out_unlock;
-
- /*
- * Check if the rec says it has a direct call but we didn't
- * find one earlier?
- */
- if (WARN_ON(rec->flags & FTRACE_FL_DIRECT))
+ ret = check_direct_ip(ip);
+ if (ret)
goto out_unlock;
- /* Make sure the ip points to the exact record */
- if (ip != rec->ip) {
- ip = rec->ip;
- /* Need to check this ip for a direct. */
- if (ftrace_find_rec_direct(ip))
- goto out_unlock;
- }
-
ret = -ENOMEM;
if (ftrace_hash_empty(direct_functions) ||
direct_functions->count > 2 * (1 << direct_functions->size_bits)) {
--
2.26.2
