On Sat, 2021-02-13 at 16:59 +0100, Hans de Goede wrote:

Hi,

On 2/13/21 4:27 PM, Guenter Roeck wrote:

quoted

On 2/13/21 7:03 AM, Hans de Goede wrote:
[ ... ]

quoted

I think something like this should work:

static int devm_delayed_work_autocancel(struct device *dev,
struct delayed_work *w,
					void (*worker)(struct
work_struct *work)) {
	INIT_DELAYED_WORK(w, worker);
	return devm_add_action(dev, (void (*action)(void
*))cancel_delayed_work_sync, w);
}

I'm not sure about the cast, that may need something like this
instead:

typedef void (*devm_action_func)(void *);

static int devm_delayed_work_autocancel(struct device *dev,
struct delayed_work *w,
					void (*worker)(struct
work_struct *work)) {
	INIT_DELAYED_WORK(w, worker);
	return devm_add_action(dev,
(devm_action_func)cancel_delayed_work_sync, w);

Unfortunately, you can not type cast function pointers in C. It is
against the C ABI.
I am sure it is done in a few places in the kernel anyway, but
those are wrong.

I see, bummer.

I think using devm_add_action() is still a good idea.

If we add a devm_clk_prepare_enable() helper that should probably be
added
to drivers/clk/clk-devres.c and not to drivers/base/devres.c .

I also still wonder if we cannot find a better place for this new
devm_delayed_work_autocancel() helper but nothing comes to mind.

I don't like the idea of including device.h from workqueue.h - and I
think this would be necessary if we added
devm_delayed_work_autocancel() as inline in workqueue.h, right?

I also see strong objection towards the devm managed clean-ups.

How about adding some devm-helpers.c in drivers/base - where we could
collect devm-based helpers - and which could be enabled by own CONFIG -
and left out by those who dislike it?

I know I wrote that the devm_delayed_work_autocancel() does probably
not warrant own file - but if you can foresee devm_work_autocancel()
and few other generally useful helpers - then we would have a place for
those. The devm stuff should in my opinion live under drivers/.

Best Regards
	Matti Vaittinen