ftrace: Add helper function ftrace_hash_move_and_update_ops()

The processes of updating a ops filter_hash is a bit complex, and requires
setting up an old hash to perform the update. This is done exactly the same
in two locations for the same reasons. Create a helper function that does it
in one place.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt (VMware) 2017-04-04 14:46:56 -04:00
parent 1a48df0041
commit e16b35ddb8
1 changed files with 53 additions and 52 deletions

View File

@ -3674,6 +3674,56 @@ ftrace_match_records(struct ftrace_hash *hash, char *buff, int len)
return match_records(hash, buff, len, NULL);
}
static void ftrace_ops_update_code(struct ftrace_ops *ops,
struct ftrace_ops_hash *old_hash)
{
struct ftrace_ops *op;
if (!ftrace_enabled)
return;
if (ops->flags & FTRACE_OPS_FL_ENABLED) {
ftrace_run_modify_code(ops, FTRACE_UPDATE_CALLS, old_hash);
return;
}
/*
* If this is the shared global_ops filter, then we need to
* check if there is another ops that shares it, is enabled.
* If so, we still need to run the modify code.
*/
if (ops->func_hash != &global_ops.local_hash)
return;
do_for_each_ftrace_op(op, ftrace_ops_list) {
if (op->func_hash == &global_ops.local_hash &&
op->flags & FTRACE_OPS_FL_ENABLED) {
ftrace_run_modify_code(op, FTRACE_UPDATE_CALLS, old_hash);
/* Only need to do this once */
return;
}
} while_for_each_ftrace_op(op);
}
static int ftrace_hash_move_and_update_ops(struct ftrace_ops *ops,
struct ftrace_hash **orig_hash,
struct ftrace_hash *hash,
int enable)
{
struct ftrace_ops_hash old_hash_ops;
struct ftrace_hash *old_hash;
int ret;
old_hash = *orig_hash;
old_hash_ops.filter_hash = ops->func_hash->filter_hash;
old_hash_ops.notrace_hash = ops->func_hash->notrace_hash;
ret = ftrace_hash_move(ops, enable, orig_hash, hash);
if (!ret) {
ftrace_ops_update_code(ops, &old_hash_ops);
free_ftrace_hash_rcu(old_hash);
}
return ret;
}
/*
* We register the module command as a template to show others how
@ -4306,44 +4356,11 @@ ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove)
return add_hash_entry(hash, ip);
}
static void ftrace_ops_update_code(struct ftrace_ops *ops,
struct ftrace_ops_hash *old_hash)
{
struct ftrace_ops *op;
if (!ftrace_enabled)
return;
if (ops->flags & FTRACE_OPS_FL_ENABLED) {
ftrace_run_modify_code(ops, FTRACE_UPDATE_CALLS, old_hash);
return;
}
/*
* If this is the shared global_ops filter, then we need to
* check if there is another ops that shares it, is enabled.
* If so, we still need to run the modify code.
*/
if (ops->func_hash != &global_ops.local_hash)
return;
do_for_each_ftrace_op(op, ftrace_ops_list) {
if (op->func_hash == &global_ops.local_hash &&
op->flags & FTRACE_OPS_FL_ENABLED) {
ftrace_run_modify_code(op, FTRACE_UPDATE_CALLS, old_hash);
/* Only need to do this once */
return;
}
} while_for_each_ftrace_op(op);
}
static int
ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len,
unsigned long ip, int remove, int reset, int enable)
{
struct ftrace_hash **orig_hash;
struct ftrace_ops_hash old_hash_ops;
struct ftrace_hash *old_hash;
struct ftrace_hash *hash;
int ret;
@ -4378,14 +4395,7 @@ ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len,
}
mutex_lock(&ftrace_lock);
old_hash = *orig_hash;
old_hash_ops.filter_hash = ops->func_hash->filter_hash;
old_hash_ops.notrace_hash = ops->func_hash->notrace_hash;
ret = ftrace_hash_move(ops, enable, orig_hash, hash);
if (!ret) {
ftrace_ops_update_code(ops, &old_hash_ops);
free_ftrace_hash_rcu(old_hash);
}
ret = ftrace_hash_move_and_update_ops(ops, orig_hash, hash, enable);
mutex_unlock(&ftrace_lock);
out_regex_unlock:
@ -4624,10 +4634,8 @@ static void __init set_ftrace_early_filters(void)
int ftrace_regex_release(struct inode *inode, struct file *file)
{
struct seq_file *m = (struct seq_file *)file->private_data;
struct ftrace_ops_hash old_hash_ops;
struct ftrace_iterator *iter;
struct ftrace_hash **orig_hash;
struct ftrace_hash *old_hash;
struct trace_parser *parser;
int filter_hash;
int ret;
@ -4657,15 +4665,8 @@ int ftrace_regex_release(struct inode *inode, struct file *file)
orig_hash = &iter->ops->func_hash->notrace_hash;
mutex_lock(&ftrace_lock);
old_hash = *orig_hash;
old_hash_ops.filter_hash = iter->ops->func_hash->filter_hash;
old_hash_ops.notrace_hash = iter->ops->func_hash->notrace_hash;
ret = ftrace_hash_move(iter->ops, filter_hash,
orig_hash, iter->hash);
if (!ret) {
ftrace_ops_update_code(iter->ops, &old_hash_ops);
free_ftrace_hash_rcu(old_hash);
}
ret = ftrace_hash_move_and_update_ops(iter->ops, orig_hash,
iter->hash, filter_hash);
mutex_unlock(&ftrace_lock);
} else {
/* For read only, the hash is the ops hash */