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LWN.net Weekly Edition for May 16, 2013
A look at the PyPy 2.0 release
PostgreSQL 9.3 beta: Federated databases and more
LWN.net Weekly Edition for May 9, 2013
(Nearly) full tickless operation in 3.10
Lock elision in the GNU C library
Posted Jan 31, 2013 21:35 UTC (Thu) by andikleen2 (guest, #52506)
With a separate code path (lock type) it's possible to use HLE. I did it, but removed that support later because it was redundant with RTM and RTM is better here because it's more flexible.
Posted Jan 31, 2013 23:08 UTC (Thu) by hpa (subscriber, #48575)
The one advantage of HLE as opposed to RTM is that you can add HLE to existing locking code so that code that runs both on TSX-enabled hardware and non-TSX-enabled hardware still can only use one code path.
So the question isn't "why can't glibc use XACQUIRE/XRELEASE", but rather "why doesn't it have to", and the answer, of course, is that glibc already supports multiple kinds of locks.
Posted Jan 31, 2013 23:11 UTC (Thu) by luto (subscriber, #39314)
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