interrupt for the CSC interrupt, then we revert to ISA. If we didn't
have an interrupt set up with hw.pcic.irq, then do polling.
Also, don't complain about ignoring function 1 for any devices except
pcic devices. This would normally only show up if someone set
hw.pcic.ignore_function_1=1.
MFC: as soon as I can test it on some troublesome laptops.
on and off since John Dyson left his work-in-progress.
It is off by default for now. sysctl vm.zeroidle_enable=1 to turn it on.
There are some hacks here to deal with the present lack of preemption - we
yield after doing a small number of pages since we wont preempt otherwise.
This is basically Matt's algorithm [with hysteresis] with an idle process
to call it in a similar way it used to be called from the idle loop.
I cleaned up the includes a fair bit here too.
level implementation stuff out of machine/globaldata.h to avoid exposing
UPAGES to lots more places. The end result is that we can double
the kernel stack size with 'options UPAGES=4' etc.
This is mainly being done for the benefit of a MFC to RELENG_4 at some
point. -current doesn't really need this so much since each interrupt
runs on its own kstack.
I'm at it also add a comment in mtx_validate() explaining the purpose
of the last change.
Basically, this fixes booting kernels compiled with MUTEX_DEBUG. What used
to happen is before we setidt from init386() [still using BTX idt], we
called mtx_init() on several mutex locks, notably Giant and some others.
This is a problem for MUTEX_DEBUG because it enables mtx_validate() which
calls kernacc(), some of which in turn requires Giant.
Fix by calling kernacc() from mtx_validate() only if (!cold).
return values a little more. Specifically, mention that a return
of 0 from NgRecvData() and NgRecvMsg() means the socket has been
closed.
Suggested by: jkh
referal from mmap to minherit for MAP_INHERIT. Fully document the
minherit.2 manual page (because frankly, my dear, however you think it
currently works is almost certainly wrong!). I may soon re-implement
MAP_COPY because I believe we can support it properly now, but I will have
to call it something else and that is for a later time.
explain the subtle side effects that are going to happen and why we go
ahead and ack the interrupt source. This stuff is tricky to get
right.
Also, emperical tests have shown that doing a shutdown in attach to be
ineffectual, so remove it from there. Analysis of the code paths
shows that nearly identical writes to these registers happen in later
parts of the code. The hanging problem on thinkpads when we change
the interrupt routing type is something else.
