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Date: Fri, 11 Jan 2002 01:38:51 +0100 (CET)
From: Ingo Molnar <mingo@elte.hu>
Reply-To: <mingo@elte.hu>
To: Linus Torvalds <torvalds@transmeta.com>
Cc: <linux-kernel@vger.kernel.org>
Subject: [patch] O(1) scheduler, -H5
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the -H5 patch adds a debugging check:

    http://redhat.com/~mingo/O(1)-scheduler/sched-O1-2.5.2-pre11-H5.patch

it adds code to catch places that call schedule() from global-cli()
sections. Right now release_kernel_lock() doesnt automatically release the
IRQ lock if there is no kernel lock held. A fair amount of code does this
still, and i think we should fix them in 2.5.

(Such code, while of questionable quality, is safe if it also holds the
big kernel lock, but it's definitely SMP-unsafe it doesnt hold the bkl -
the BUG() assert only catches the later case.)

(Andi Kleen noticed this on the first day the patch was released, and
Andrew Morton reminded me today that i forgot to fix it ... :-| )

my systems do not trigger the BUG(), so there cannot be all that much
broken code left.

	Ingo

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