Re: [PATCH v3 2/6] PM / Runtime: introduce pm_runtime_set[get]_memalloc_noio()

From: Alan Stern
Date: Wed Oct 31 2012 - 11:19:56 EST


On Wed, 31 Oct 2012, Ming Lei wrote:

> The below idea may help the problem which 'memalloc_noio' flag isn't set during
> usb_reset_device().
>
> - for usb mass storage device, call pm_runtime_set_memalloc_noio(true)
> inside usb_stor_probe2() and uas_probe(), and call
> pm_runtime_set_memalloc_noio(false) inside uas_disconnect()
> and usb_stor_disconnect().

Why would you want to do that? The probe and disconnect routines
usually -- but not always -- run in the khubd thread. Surely you don't
want to prevent khubd from using GFP_KERNEL?

And what if probe runs in khubd but disconnect runs in a different
thread?

Alan Stern

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/