Messages in this thread | | | Date | Thu, 29 Mar 2018 16:25:33 +0200 | From | Lukas Wunner <> | Subject | Re: [PATCHv3] gpio: Remove VLA from gpiolib |
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On Wed, Mar 28, 2018 at 11:18:09AM -0700, Laura Abbott wrote: > The new challenge is to remove VLAs from the kernel > (see https://lkml.org/lkml/2018/3/7/621) to eventually > turn on -Wvla. > > Using a kmalloc array is the easy way to fix this but kmalloc is still > more expensive than stack allocation. Introduce a fast path with a > fixed size stack array to cover most chip with gpios below some fixed > amount. The slow path dynamically allocates an array to cover those > chips with a large number of gpios. > > Signed-off-by: Lukas Wunner <lukas@wunner.de> > Signed-off-by: Laura Abbott <labbott@redhat.com> > --- > v3: Split out from the series since patches have been picked up > independently. Fold in patch from Lukas Wunner to introduce slow/fast > paths. I took his suggestions to go with 384 as the maximum number of > gpios. Also fixed one 0-day bot issue where I forgot to change the > return type.
I've just given this a whirl with gpio-hammer and it works nicely, so FWIW:
Reviewed-and-tested-by: Lukas Wunner <lukas@wunner.de>
Thanks a lot for doing this Laura, and most of all thanks for the proverbial "dogged persistence and patience"! (https://lwn.net/Articles/697029/)
Lukas
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