Re: [PATCH v2] memcg: replace memcg ID idr with xarray

[Matthew Wilcox]

On Thu, Aug 15, 2024 at 07:31:43PM +0000, Roman Gushchin wrote:
> There is another subtle change here: xa_alloc() returns -EBUSY in the case
> of the address space exhaustion, while the old code returned -ENOSPC.
> It's unlikely a big practical problem.

I decided that EBUSY was the right errno for this situation;

#define EBUSY           16      /* Device or resource busy */
#define ENOSPC          28      /* No space left on device */

ENOSPC seemed wrong; the device isn't out of space.