process is on the alternate stack or not. For compatibility
with sigstack(2) state is being updated if such is needed.
We now determine whether the process is on the alternate
stack by looking at its stack pointer. This allows a process
to siglongjmp from a signal handler on the alternate stack
to the place of the sigsetjmp on the normal stack. When
maintaining state, this would have invalidated the state
information and causing a subsequent signal to be delivered
on the normal stack instead of the alternate stack.
PR: 22286
counter register in-CPU.
This is to be used as a fast "timer", where linearity is more important
than time, and multiple lines in the linearity caused by multiple CPUs
in an SMP machine is not a problem.
This adds no code whatsoever to the FreeBSD kernel until it is actually
used, and then as a single-instruction inline routine (except for the
80386 and 80486 where it is some more inline code around nanotime(9).
Reviewed by: bde, kris, jhb
kernel backing store.
* Implement syscalls via break instructions.
* Fix backing store copying in cpu_fork() so that the child gets the right
register values.
This thing is actually starting to work now. This set of changes takes me
up to the second execve (the one which runs the first shell). Next stop
single-user mode :-).
exceptions from both kernel and user mode.
* Fix context switching so that we can switch back to a proc which we
switched away from (we were saving the state in the wrong place).
* Implement lazy switching of the high-fp state. This needs to be looked
at again for SMP to cope with the case of a process migrating from one
processor to another while it has the high-fp state.
* Make setregs() work properly. I still think this should be called
cpu_exec() or something.
* Various other minor fixes.
With this lot, we can execve() /sbin/init and we get all the way up to its
first syscall. At that point, we stop because syscall handling is not done
yet.
not work on any real hardware (or fully work on any simulator). Much more
needs to happen before this is actually functional but its nice to see
the FreeBSD copyright message appear in the ia64 simulator.
