Re: [PATCH v2] scsi: hisi_sas: optimise DMA slot memory

From: Martin K. Petersen
Date: Sat Jul 01 2017 - 17:07:37 EST



John,

> Currently we allocate 3 sets of DMA memories from separate
> pools for each slot. This is inefficient in terms of memory usage
> (buffers are less than 1 page in size, so we lose due to alignment),
> and also time spent in doing 3 allocations + de-allocations per slot,
> instead of 1.
>
> To optimise, combine the 3 DMA buffers into a single buffer from a
> single pool.

Applied to 4.13/scsi-queue. Thank you!

--
Martin K. Petersen Oracle Linux Engineering