Re: [PATCH RESEND v5] mmc: core: Remove bounce buffer in mmc_send_cxd_data()

From: S, Venkatraman
Date: Thu Aug 02 2012 - 10:49:12 EST


On Thu, Aug 2, 2012 at 12:37 PM, Kyungsik Lee <kyungsik.lee@xxxxxxx> wrote:
> It is expected that Extended CSD register(the size of this register
> is larger than CID/CSD) will be referenced more frequently as more
> fields have been added to Extended CSD and it seems that it is not
> a good option to double the memory used.
>
> This patch is intended to avoid the use of bounce buffer for reading
> Extended CSD register in mmc_send_cxd_data(). It will provide a better
> performance gain by removing memcpy() overhead for a half KiB and
> a redundant bounce buffer allocated repeatedly at the cost of providing
> DMA-capable buffer from upper caller(but on-stack buffer is allowed
> with no performance gain).
>
> Signed-off-by: Kyungsik Lee <kyungsik.lee@xxxxxxx>
> Signed-off-by: S, Venkatraman <svenkatr@xxxxxx>

I don't think my sign off is warranted. I gave just an illustration.
You can add my
Reviewed-by: Venkatraman S <svenkatr@xxxxxx>

Regards,
Venkat.
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