On Wed, 3 Apr 2024 11:53:14 -0700
"Paul E. McKenney" <paul...@kernel.org> wrote:
> @@ -5366,6 +5366,13 @@ static void remove_direct_functions_hash(struct
> ftrace_hash *hash, unsigned long
> }
> }
>
> +static void register_ftrace_direct_cb(struct rcu_head *rhp)
> +{
> + struct ftrace_hash *fhp = container_of(rhp, struct ftrace_hash, rcu);
> +
> + free_ftrace_hash(fhp);
> +}
> +
> /**
> * register_ftrace_direct - Call a custom trampoline directly
> * for multiple functions registered in @ops
> @@ -5464,10 +5471,8 @@ int register_ftrace_direct(struct ftrace_ops *ops,
> unsigned long addr)
> out_unlock:
> mutex_unlock(&direct_mutex);
>
> - if (free_hash && free_hash != EMPTY_HASH) {
> - synchronize_rcu_tasks();
> - free_ftrace_hash(free_hash);
> - }
> + if (free_hash && free_hash != EMPTY_HASH)
> + call_rcu_tasks(&free_hash->rcu, register_ftrace_direct_cb);
>
> if (new_hash)
> free_ftrace_hash(new_hash);
I'm getting ready to go on PTO, but a quick glance doesn't look like this
would cause any harm.
-- Steve
