Besides the fact that we did not have that for the current supported
boards, that makes sense for this new, virtualized mode, that is meant
to be run on top of full-fledged x86 64 CPUs.
By having xAPIC mode access only, Jailhouse has to intercept those MMIO
reads and writes, in order to examine what they do and arbitrate if it's
safe or not (e.g. not all values are accepted to ICR register). This
means that we can't run away from having a VM-exit event for each and
every access to APIC memory region and this impacts the latency the
guest OS observes over bare metal a lot.
When in x2APIC mode, Jailhouse does not require VM-exits for MSR
accesses other that writes to the ICR register, so the latency the guest
observes is reduced to almost zero.
Here are some outputs of the the command line
$ sudo ./tools/jailhouse cell stats tiny-demo
on a Jailhouse's root cell console, for one of the Zephyr demos using
LOAPIC timers, left for a couple of seconds:
Statistics for tiny-demo cell (x2APIC root, x2APIC inmate)
COUNTER SUM PER SEC
vmexits_total 7 0
vmexits_management 3 0
vmexits_cr 2 0
vmexits_cpuid 1 0
vmexits_msr 1 0
vmexits_exception 0 0
vmexits_hypercall 0 0
vmexits_mmio 0 0
vmexits_pio 0 0
vmexits_xapic 0 0
vmexits_xsetbv 0 0
Statistics for tiny-demo cell (xAPIC root, xAPIC inmate)
COUNTER SUM PER SEC
vmexits_total 4087 40
vmexits_xapic 4080 40
vmexits_management 3 0
vmexits_cr 2 0
vmexits_cpuid 1 0
vmexits_msr 1 0
vmexits_exception 0 0
vmexits_hypercall 0 0
vmexits_mmio 0 0
vmexits_pio 0 0
vmexits_xsetbv 0 0
Statistics for tiny-demo cell (xAPIC root, x2APIC inmate)
COUNTER SUM PER SEC
vmexits_total 4087 40
vmexits_msr 4080 40
vmexits_management 3 0
vmexits_cr 2 0
vmexits_cpuid 1 0
vmexits_exception 0 0
vmexits_hypercall 0 0
vmexits_mmio 0 0
vmexits_pio 0 0
vmexits_xapic 0 0
vmexits_xsetbv 0 0
See that under x2APIC mode on both Jailhouse/root-cell and guest, the
interruptions from the hypervisor are minimal. That is not the case when
Jailhouse is on xAPIC mode, though. Note also that, as a plus, x2APIC
accesses on the guest will map to xAPIC MMIO on the hypervisor just
fine.
Signed-off-by: Gustavo Lima Chaves <gustavo.lima.chaves@intel.com>
We were unnecessarily pulling in headers which resulted in kernel.h
being pulled in, which is undesirable since arch/cpu.h pulls in
these headers.
Added integral type headers since we do need those.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Convert code to use u{8,16,32,64}_t and s{8,16,32,64}_t instead of C99
integer types. This handles the remaining includes and kernel, plus
touching up various points that we skipped because of include
dependancies. We also convert the PRI printf formatters in the arch
code over to normal formatters.
Jira: ZEP-2051
Change-Id: Iecbb12601a3ee4ea936fd7ddea37788a645b08b0
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
Replace the existing Apache 2.0 boilerplate header with an SPDX tag
throughout the zephyr code tree. This patch was generated via a
script run over the master branch.
Also updated doc/porting/application.rst that had a dependency on
line numbers in a literal include.
Manually updated subsys/logging/sys_log.c that had a malformed
header in the original file. Also cleanup several cases that already
had a SPDX tag and we either got a duplicate or missed updating.
Jira: ZEP-1457
Change-Id: I6131a1d4ee0e58f5b938300c2d2fc77d2e69572c
Signed-off-by: David B. Kinder <david.b.kinder@intel.com>
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
Originally, x86 just supported APIC. Then later support
for the Mint Valley Interrupt Controller was added. This
controller is mostly similar to the APIC with some differences,
but was integrated in a somewhat hacked-up fashion.
Now we define irq_controller.h, which is a layer of abstraction
between the core arch code and the interrupt controller
implementation.
Contents of the API:
- Controllers with a fixed irq-to-vector mapping define
_IRQ_CONTROLLER_VECTOR_MAPPING(irq) to obtain a compile-time
map between the two.
- _irq_controller_program() notifies the interrupt controller
what vector will be used for a particular IRQ along with triggering
flags
- _irq_controller_isr_vector_get() reports the vector number of
the IRQ currently being serviced
- In assembly language domain, _irq_controller_eoi implements
EOI handling.
- Since triggering options can vary, some common defines for
triggering IRQ_TRIGGER_EDGE, IRQ_TRIGGER_LEVEL, IRQ_POLARITY_HIGH,
IRQ_POLARITY_LOW introduced.
Specific changes made:
- New Kconfig X86_FIXED_IRQ_MAPPING for those interrupt controllers
that have a fixed relationship between IRQ lines and IDT vectors.
- MVIC driver rewritten per the HAS instead of the tortuous methods
used to get it to behave like LOAPIC. We are no longer writing values
to reserved registers. Additional assertions added.
- Some cleanup in the loapic_timer driver to make the MVIC differences
clearer.
- Unused APIs removed, or folded into calling code when used just once.
- MVIC doesn't bother to write a -1 to the intList priority field since
it gets ignored anyway
Issue: ZEP-48
Change-Id: I071a477ea68c36e00c3d0653ce74b3583454154d
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
