Re: [PATCH v2] mmc: fix async request mechanism for sequential read scenarios

[Konstantin Dorfman <kdorfman@codeaurora.org>]

On 11/05/2012 08:20 AM, Per Förlin wrote:
> Hi Konstantin,
> 
> On 11/01/2012 03:40 PM, Konstantin Dorfman wrote:
>> When current request is running on the bus and if next request fetched
>> by mmcqd is NULL, mmc context (mmcqd thread) gets blocked until the
>> current request completes. This means if new request comes in while
>> the mmcqd thread is blocked, this new request can not be prepared in
>> parallel to current ongoing request. This may result in latency to
>> start new request.
>>
>> This change allows to wake up the MMC thread (which
>> is waiting for the current running request to complete). Now once the
>> MMC thread is woken up, new request can be fetched and prepared in
>> parallel to current running request which means this new request can
>> be started immediately after the current running request completes.
>>
>> With this change read throughput is improved by 16%.
> What HW and what test cases have you been running?

I use the msm_sdcc controller and ran lmdd, tiotest, iozone benchmark
tool (details were on other mail in this thread).

I ran it on Qualcomm® SnapdragonT S4 ProAPQ8064

Thanks,

-- 
Konstantin Dorfman,
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