Re: [PATCH V2 for-4.21 2/2] blk-mq: alloc q->queue_ctx as normal array

Greg Kroah-Hartman
2018-11-16T14:06:25Z

On Fri, Nov 16, 2018 at 07:23:11PM +0800, Ming Lei wrote:
> Now q->queue_ctx is just one read-mostly table for query the
> 'blk_mq_ctx' instance from one cpu index, it isn't necessary
> to allocate it as percpu variable. One simple array may be
> more efficient.

"may be", have you run benchmarks to be sure? If so, can you add the
results of them to this changelog? If there is no measurable
difference, then why make this change at all?

thanks,

greg k-h