Messages in this thread | | | Date | Thu, 7 Sep 2000 19:14:28 +0200 | From | Jamie Lokier <> | Subject | Re: spin_lock forgets to clobber memory and other smp fixes [was Re: [patch] waitqueue optimization, 2.4.0-test7] |
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Andrea Arcangeli wrote: > Said that if your compiler puts the read before the spin_lock without the > memory clobber, it is allowed to do that, and in such case you would proof > it was a real world bug (not just a "documentation" one).
Yes, it does.
> Or maybe your testcase was a bit different then mine, in such case please > send it to me (I'm curious indeed :).
int *p; int func() { int x = *p; __asm__ __volatile ("zzz" : :); x = *p; return x; }
In output:
.ident "GCC: (GNU) 2.96 20000724 (experimental)"
From the Red Hat 7 beta.
-- Jamie - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/
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