Re: [Qemu-devel] [PATCH 0/2] macio: switch over to new byte-aligned DMA helpers

[Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>]

On 30/05/16 22:19, Aurelien Jarno wrote:

> On 2016-05-27 09:48, Mark Cave-Ayland wrote:
>> Here is a tidied up version of my patch to convert the macio controller over to
>> using the new byte-aligned DMA helpers.
>>
>> The first patch is just a hack and temporarily disables unaligned iovec
>> truncation in the DMA helper (as discussed in the recent thread) until Paolo or
>> someone else can devise a proper solution. Without this, the subsequent switch
>> over to the DMA helpers will appear to work during a Darwin PPC install but the
>> resulting image is corrupt and will fail to boot.
>>
>> The second patch is the real one and switches the macio controller over to use
>> the new byte-aligned DMA helpers. Here I see a speed-up of around 2.5x-3x for
>> a typical Darwin PPC installation compared to the previous code.
>>
>> Aurelien, I'd be grateful if you could test the TRIM path as I know this is
>> something you've had issues with before and I couldn't quite figure out how to
>> reproduce your TRIM tests from before.
> 
> I have just tested the TRIM path, all works fine with your 2 patches
> applied.

Thanks a lot for testing this, Aurelien. In that case I'll resubmit
patch 2 officially once Paolo has figured out the correct solution for
the iovec truncation.


ATB,

Mark.