Chen, Kenneth W wrote:
Christoph Lameter wrote on Thursday, March 30, 2006 6:38 PM
Neither one is correct because there will always be one combination of
clear_bit with these macros that does not generate the required memory
barrier.
Can you give an example? Which combination?
For Option(1)
smp_mb__before_clear_bit()
clear_bit(...)(
Sorry, you totally lost me. It could me I'm extremely slow today. For
option (1), on ia64, clear_bit has release semantic already. The comb
of __before_clear_bit + clear_bit provides the required ordering. Did
I miss something? By the way, we are talking about detail implementation
on one specific architecture. Not some generic concept that clear_bit
has no ordering stuff in there.
The memory ordering that above combination should produce is a
Linux style smp_mb before the clear_bit. Not a release.
--
SUSE Labs, Novell Inc.
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 [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
