Re: [PATCH] Text Edit Lock - Architecture Independent Code

Ingo Molnar
2009-03-03T00:33:45Z

* Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> wrote:

> +/*
> + * Take and release the kernel text modification lock, used for code patching.
> + * Users of this lock can sleep.
> + */
> +extern void kernel_text_lock(void);
> +extern void kernel_text_unlock(void);

Locking APIs with hidden semantics are very ugly. Remember
lock_kernel()?

> +/*
> + * mutex protecting text section modification (dynamic code patching).
> + * some users need to sleep (allocating memory...) while they hold this lock.
> + */
> +static DEFINE_MUTEX(text_mutex);

Please update those sites to do an explicit:

mutex_lock(&text_mutex);

instead.

That way we save a function call, and we'll also see exactly
what type of lock is being taken, etc.

Ingo