On 07/31/2012 07:43 PM, Peter Maydell wrote:
On 27 July 2012 20:29, Igor Mitsyanko <i.mitsya...@samsung.com> wrote:
Rather that repeatedly call SD_GET_CLASS() in a loop, call it once before
a loop starts.
Anthony claims that SD_GET_CLASS should be cheap enough that we don't
need to hoist it out of loops like this. Do you have profiling data
or similar that caused you to write this patch?
-- PMM
Well, I've tested it by measuring an execution time of a 4Kb write to SD
card, results showed that arithmetic mean of time for one 4k write was
less by ~300us in sequence with SD_GET_CLASS extracted from the loop.
Although I ran this test several times, I have little faith in test
methodology and results, it obviously showed significant dispersion
between measured time of distinct 4K writes (200-300% if I recall
correctly). I really have no objection no objection to dropping this patch.
