Messages in this thread | | | Date | Thu, 14 Dec 2023 22:45:17 +0800 | From | Kent Gibson <> | Subject | Re: [PATCH v2 2/5] gpiolib: cdev: relocate debounce_period_us from struct gpio_desc |
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On Thu, Dec 14, 2023 at 03:29:28PM +0100, Bartosz Golaszewski wrote: > On Thu, Dec 14, 2023 at 10:58 AM Kent Gibson <warthog618@gmail.com> wrote: > > > > > > +/* > > + * Used to populate gpio_v2_line_info with cdev specific fields not contained > > + * in the struct gpio_desc. > > + * A line is determined to contain supplemental information by > > + * line_is_supplemental(). > > + */ > > +static struct { > > + /* a rbtree of the struct lines containing the supplemental info */ > > + struct rb_root tree; > > + /* covers tree */ > > + spinlock_t lock; > > Looks like this is never taken from atomic context? Can this be a mutex instead? >
Correct, only from thread context.
Can be a mutex, but it only covers tree lookups which should be quick as the tree is kept minimal, and I wouldn't expect it to ever get to the mutex slowpath, so a spinlock seemed more appropriate.
Cheers, Kent.
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