Re: RT patch acceptance

From: john cooper
Date: Thu May 26 2005 - 16:30:24 EST


Sven-Thorsten Dietrich wrote:
On Thu, 2005-05-26 at 16:38 -0400, john cooper wrote:
Spin if the lock is contended and the owner is active
on a cpu under the assumption the lock owner's average
hold time is less than that of a context switch. There
are restrictions as once a path holds an adaptive
mutex as a spin lock it cannot acquire another adaptive
mutex as a blocking lock.

It might be simpler to get things working with a basic implementation
first, (status quo), and then look into adding something like this.

I wasn't suggesting this is the time to consider doing so,
but rather pointing it out as an available optimization.

I don't see how this approach decreases the complexity of the task at
hand, especially not in regards to concurrency.

It increases the efficiency of the mutex as we don't incur
context switches (in general) unless necessary. Concurrency
isn't fundamentally affected.

-john


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