On Tue, 2010-11-16 at 08:38 -0800, Linus Torvalds wrote:
Yes, there's various implementations floating around, and we already
have one in-kernel ( net/rds/xlist.h ), mason and axboe and me have been
kicking around various patches using that thing in other circumstances
[ At some point we had perf -- what now is kernel/irq_work.c -- using
it as well, but the new code grew too complex due to requirements
from Huang ]
Right, I don't generally object to lockless things, but they either need
to be 1) faster than the existing code, and/or 2) have a very convincing
use-case (other than performance) for their added complexity.
Afaict the proposed patch adds lots more LOCK'ed instructions into that
allocator path than it removes, ie its a slow down for existing users.