On 10/14/2011 02:30 PM, Peter Maydell wrote:
I've also just discovered that it's no use on Oneiric,
where the linker warning has gone away but the syscall
still always returns ENOSYS.
I think we should just always use the gthread implementation
rather than preferring a non-portable-and-hard-to-detect
set of functions (which increases the set of different
configs we need to test with). If there's a performance problem
with that we should get it fixed in gthread:-)
A user-space longjmp will always be slower than a mutex+condvar+context
switch. We're talking _orders of magnitude_ slower. At this point it's
better to write assembly, since we already support only a dozen TCG targets.
I played with an alternative implementation using a 2-barrier instead of
mutex+condvar, but it didn't give any speedup and was still much slower
than gthread.
Paolo
