Messages in this thread | | | From | Gwendal Grignou <> | Date | Mon, 10 Jan 2022 01:31:23 -0800 | Subject | Re: [PATCH 00/17] Add export symbol namespace PL_CHROMEOS |
| |
On Thu, Jan 6, 2022 at 2:06 AM Mauro Carvalho Chehab <mchehab@kernel.org> wrote: > > Em Wed, 5 Jan 2022 20:26:36 -0800 > Gwendal Grignou <gwendal@chromium.org> escreveu: > > > On Wed, Jan 5, 2022 at 2:58 PM Dmitry Torokhov <dtor@chromium.org> wrote: > > > > > > Hi Gwendal, > > > > > > On Wed, Jan 5, 2022 at 2:07 PM Gwendal Grignou <gwendal@chromium.org> wrote: > > > > > > > > Add a symbol namespace for functions exported by the plaform chromeos > > > > subsystem. > > > > > > It would be great to explain why this is needed/desirable. What are > > > the benefits of introducing this namespace? What problem are you > > > trying to solve? > > The issue came when reviewing an iio sensor > > (https://www.spinics.net/lists/linux-iio/msg66280.html). I wanted to > > be ahead of the curve (for once). > > Patch 01 should clearly document the reason why this is needed. > Yet, see below. > > While I see value on using namespaces, we should have extra care when > this is used for kAPIs designed for a product/system. I mean, what > prevents that the affected drivers won't support some day different > non-ChromeOS products? We have a media driver originally written to > work with the One Laptop Per Children hardware, that used some > product-specific kAPIs, that were extended a couple years later to > cover different types of hardware. > > What happens if some day, a driver introduced to be used on a ChromeOS > hardware would also be used by a non-ChromeOS hardware? This could > become messy as times goes by. > > Instead, IMO, it would make sense to have per-subsystem namespaces. > So, for instance, placing iio under an IIO-specific namespace > (and the same for other subsystems) makes more sense on my > eyes, as the namespace boundary will be clearer, and an IIO driver > will always be IIO, no matter on what hardware such driver would > be used. I based this patchset on the current/future use in the IIO subsystem, where the namespaces are used for small subsystem like HID, IIO_HID_ATTRIBUTES, or code shared among sensors drivers of the same vendor (LTC2497, more to come). Since the usage of namespace in the kernel is not clearly defined yet, I wait for the dust to settle and more usage to emerge before tuning this patchset.
Thanks, Gwendal. > > Thanks, > Mauro
| |