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Date: Thu, 17 Apr 2003 00:37:28 -0700
From: Terry Lambert <tlambert2@mindspring.com>
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cc: David Xu <davidxu@viatech.com.cn>
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Subject: Re: libpthread patch
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Daniel Eischen wrote:
> The critical section is to prevent the thread from being
> swapped out by the kernel and sent to another KSE.  That's
> it; it's not meant to do the same thing as locking.
> There's per-kse stuff that needs to be accessed that
> isn't correct if the thread gets run on another KSE,
> regardless of whether or not a lock protects it.

I guess the next question is why thread-lending (ala NT,
MACH, etc.) isn't supportable.


> If it wasn't possible for the kernel to send completed
> threads from one KSE to another (within the same KSE
> group), we probably wouldn't need critical sections
> (at least as currently implemented).

Is there a particular performance/other reason this is allowed?

-- Terry