From: Kent Gibson <warthog618@gmail.com>
To: Andy Shevchenko <andy@kernel.org>
Cc: linux-kernel@vger.kernel.org, linux-gpio@vger.kernel.org,
brgl@bgdev.pl, linus.walleij@linaro.org
Subject: Re: [PATCH 3/4] gpiolib: cdev: reduce locking in gpio_desc_to_lineinfo()
Date: Wed, 13 Dec 2023 22:07:28 +0800 [thread overview]
Message-ID: <ZXm6oHjb7CRZ8-0f@rigel> (raw)
In-Reply-To: <ZXm4C7KVkMwL4_sX@smile.fi.intel.com>
On Wed, Dec 13, 2023 at 03:56:27PM +0200, Andy Shevchenko wrote:
> On Tue, Dec 12, 2023 at 01:42:52PM +0800, Kent Gibson wrote:
> > Reduce the time holding the gpio_lock by snapshotting the desc flags,
> > rather than testing them individually while holding the lock.
> >
> > Accept that the calculation of the used field is inherently racy, and
> > only check the availabilty of the line from pinctrl if other checks
> > pass, so avoiding the check for lines that are otherwise in use.
>
> ...
>
> > - bool ok_for_pinctrl;
> > - unsigned long flags;
> > + unsigned long iflags, dflags;
>
> With a preliminary conversion to cleanup.h this whole change becomes cleaner,
> no?
>
You mean the scoped guards? Dunno - haven't used them.
Care to provide more detail?
Cheers,
Kent.
next prev parent reply other threads:[~2023-12-13 14:07 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-12-12 5:42 [PATCH 0/4] gpiolib: cdev: relocate debounce_period_us Kent Gibson
2023-12-12 5:42 ` [PATCH 1/4] gpiolib: cdev: relocate debounce_period_us from struct gpio_desc Kent Gibson
2023-12-13 13:54 ` Andy Shevchenko
2023-12-13 14:27 ` Kent Gibson
2023-12-13 15:40 ` Bartosz Golaszewski
2023-12-13 15:59 ` Kent Gibson
2023-12-13 16:12 ` Andy Shevchenko
2023-12-13 16:15 ` Bartosz Golaszewski
2023-12-13 16:29 ` Andy Shevchenko
2023-12-13 19:03 ` Bartosz Golaszewski
2023-12-13 20:07 ` Andy Shevchenko
2023-12-14 0:18 ` Kent Gibson
2023-12-14 2:15 ` Kent Gibson
2023-12-14 9:40 ` Bartosz Golaszewski
2023-12-14 14:35 ` Andy Shevchenko
2023-12-14 14:47 ` Kent Gibson
2023-12-13 16:14 ` Bartosz Golaszewski
2023-12-13 16:15 ` Kent Gibson
2023-12-13 16:16 ` Bartosz Golaszewski
2023-12-13 16:27 ` Andy Shevchenko
2023-12-12 5:42 ` [PATCH 2/4] gpiolib: remove " Kent Gibson
2023-12-12 5:42 ` [PATCH 3/4] gpiolib: cdev: reduce locking in gpio_desc_to_lineinfo() Kent Gibson
2023-12-13 13:56 ` Andy Shevchenko
2023-12-13 14:07 ` Kent Gibson [this message]
2023-12-13 15:05 ` Andy Shevchenko
2023-12-13 15:11 ` Kent Gibson
2023-12-13 15:28 ` Andy Shevchenko
2023-12-12 5:42 ` [PATCH 4/4] gpiolib: cdev: improve documentation of get/set values Kent Gibson
2023-12-12 17:09 ` [PATCH 0/4] gpiolib: cdev: relocate debounce_period_us Bartosz Golaszewski
2023-12-12 23:58 ` Kent Gibson
2023-12-13 10:03 ` Bartosz Golaszewski
2023-12-13 13:17 ` Kent Gibson
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