Re: [LAD] concurrent access on smp

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To: Emanuel Rumpf <xbran@...>
Cc: <Linux-audio-dev@...>
Date: Monday, October 22, 2012 - 1:18 am

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On Mon, 2012-10-22 at 02:34 +0200, Emanuel Rumpf wrote:

If everyone is reading, updates are not necessary, so this is fast.
Writes are the problem because they can invalidate the cache of other
CPUs/cores.

> 2. is there a faster or more convenient method, such as

On CPUs, not really. The cache is transparently controlled by the
hardware (though GPUs and some other weird chips do have explicit shared
cache).

There are shared levels of cache (on multi-core chips), it's just slower
than L1. General registers are not shared.

(Sometimes volatile can have surprising performance effects on shared
variables, if you're playing around and benchmarking, but it doesn't
really guarantee anything).

-dr

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Messages in current thread:
[LAD] concurrent access on smp, Emanuel Rumpf, (Mon Oct 22, 12:34 am)
Re: [LAD] concurrent access on smp, Tvrtko Ursulin, (Wed Oct 31, 8:04 pm)
Re: [LAD] concurrent access on smp, Paul Giblock, (Wed Oct 31, 8:34 pm)
Re: [LAD] concurrent access on smp, Clemens Ladisch, (Thu Nov 1, 7:56 am)
Re: [LAD] concurrent access on smp, David Robillard, (Mon Oct 22, 1:18 am)