Re: [patch 2] mm: speculative get_page
From: Nick Piggin
Date: Tue Jun 28 2005 - 01:30:25 EST
David S. Miller wrote:
From: Nick Piggin <nickpiggin@xxxxxxxxxxxx>
Subject: Re: [patch 2] mm: speculative get_page
Date: Tue, 28 Jun 2005 14:50:31 +1000
William Lee Irwin III wrote:
On Tue, Jun 28, 2005 at 11:42:16AM +1000, Nick Piggin wrote:
spin_unlock() does not imply a memory barrier.
Intriguing...
BTW, I disagree with this assertion. spin_unlock() does imply a
memory barrier.
All memory operations before the release of the lock must execute
before the lock release memory operation is globally visible.
Yes, it appears that way from looking at a sample set of arch
code too (ie. those without strictly ordered stores put an
explicit barrier there).
I've always understood spin_unlock to imply a barrier.
Send instant messages to your online friends http://au.messenger.yahoo.com
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/