On Thu, Oct 01, 2020 at 11:48:41PM +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. > > Tested-by: Veronika Kabatova <vkabatov@xxxxxxxxxx> > Reviewed-by: Christoph Hellwig <hch@xxxxxx> > Cc: Sagi Grimberg <sagi@xxxxxxxxxxx> > Cc: Tejun Heo <tj@xxxxxxxxxx> > Cc: Christoph Hellwig <hch@xxxxxx> > Cc: Jens Axboe <axboe@xxxxxxxxx> > Cc: Bart Van Assche <bvanassche@xxxxxxx> > Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx> Acked-by: Tejun Heo <tj@xxxxxxxxxx> Thanks. -- tejun
