Select the Xen idle routine for Xen, mwait if supported by the CPU and
it is not AMD and halt otherwise. As reported by Christoph Egger,
AMD Barcelona keeps the CPU in C0 state with MWAIT, contrary to HLT,
which uses C1 and therefore much less power.
in cpu_attach(), and doing it here will overwrite the cpu_number of the
physical CPU with the one from the virtual CPU (which is always 0).
XXX is ioapic_bsp_id read somewhere ?
on amd64). Make sure to use the right type to store and manipulate them.
This fixes amd64, where basically any event channel > 31 was not working
(and you get there after starting/stopping a domU a few times). Things
would occasionally unwedge though the spllower() callbacks.
Register a ipl callback for IPL_HIGH.
if the current ipl level is too high, just record the event in a bitmap,
and record IPL_HIGH as pending. The callback will process the pending events.
(domU only). PAE support is enabled by 'options PAE', see the new XEN3PAE_DOMU
and INSTALL_XEN3PAE_DOMU kernel config files.
See the comments in arch/i386/include/{pte.h,pmap.h} to see how it works.
In short, we still handle it as a 2-level MMU, with the second level page
directory being 4 pages in size. pmap switching is done by switching the
L2 pages in the L3 entries, instead of loading %cr3. This is almost required
by Xen, which handle the last L2 page (the one mapping 0xc0000000 - 0xffffffff)
in a very special way. But this approach should also work for native PAE
support if ever supported (in fact, the pmap should almost suport native
PAE, what's missing is bootstrap code in locore.S).
pmap_bootstrap()/init386() wants to map a few additionnal things after
first_avail that we didn't account for, before pmap_growkernel() is
used/functionnal, and if the loaded kernel is close to the end of
the last L2 slot we loose. Should fix port-xen/37761 by YAMAMOTO Takashi.
Fix a XENPRINTF() so that low debug builds again.
branch is still active and will see i386PAE support developement).
Sumary of changes:
- switch xeni386 to the x86/x86/pmap.c, and the xen/x86/x86_xpmap.c
pmap bootstrap.
- merge back most of xen/i386/ to i386/i386
- change the build to reduce diffs between i386 and amd64 in file locations
- remove include files that were identical to the i386/amd64 counterparts,
the build will find them via the xen-ma/machine link.
- make tss per-cpu. this considerably speeds up context switch for,
at least, pentium4, where ltr instruction seems very slow.
i386, xen:
- kill cpu_maxproc.
kvm86:
- adapt to per-cpu tss.
- cleanup and simplify.
- move kvm86_mp_lock to more meaningful place.
- disable preemption during a call.
ACPI wakeup code and teach it how to start the APs again. As a side
effect the CPU_START interface allows choosing between different
bootstrap codes more easily now.
- Reduce available SPL levels for hardware devices to none, vm, sched, high.
- Acquire kernel_lock only for interrupts at IPL_VM.
- Implement threaded soft interrupts.
- Replace most inline assembly with proper functions. As a side effect
this reduces the size of amd64 GENERIC by about 120kB, and i386 by a
smaller amount. Nearly all of the inlines did something slow, or something
that does not need to be fast.
- Make curcpu() and curlwp functions proper, unless __GNUC__ && _KERNEL.
In that case make them inlines. Makes curlwp LKM and preemption safe.
- Make bus_space and bus_dma more LKM friendly.
- Share a few more files between the ports.
- Other minor changes.
interface doesn't allow it), so that .e.g bus_dma_subregion() has a chance
to work. Unfortunably a stock Xen hypervisor won't allow a upper bound less
than 2^31 (2GB) so devices like bce(4) will need a hacked hypervisor to
work properly.
Patch by Slava Semushin <slava.semushin@gmail.com>
Again, this was tested by comparing obj files from a pristine and a patched
source tree against an i386/ALL kernel, and also for src/sbin/fsck_ffs,
src/sbin/fsdb and src/usr.sbin/makefs. Only changes in assert() line numbers
were detected in 'objdump -d' output.
