Re: [PATCH V2 1/2] percpu_ref: reduce memory footprint of percpu_ref in fast path

[Christoph Hellwig]

On Wed, Sep 02, 2020 at 08:26:42PM +0800, Ming Lei wrote:
> 'struct percpu_ref' is often embedded into one user structure, and the
> instance is usually referenced in fast path, however actually only
> 'percpu_count_ptr' is needed in fast path.
> 
> So move other fields into one new structure of 'percpu_ref_data', and
> allocate it dynamically via kzalloc(), then memory footprint of
> 'percpu_ref' in fast path is reduced a lot and becomes suitable to put
> into hot cacheline of user structure.

This looks good:

Reviewed-by: Christoph Hellwig <hch@xxxxxx>