Currently during KVM initialization on POWER, kvm_fixup_page_sizes()
rewrites a bunch of information in the cpu state to reflect the
capabilities of the host MMU and KVM. This overwrites the information
that's already there reflecting how the TCG implementation of the MMU will
operate.
This means that we can get guest-visibly different behaviour between KVM
and TCG (and between different KVM implementations). That's bad. It also
prevents migration between KVM and TCG.
The pseries machine type now has filtering of the pagesizes it allows the
guest to use which means it can present a consistent model of the MMU
across all accelerators.
So, we can now replace kvm_fixup_page_sizes() with kvm_check_mmu() which
merely verifies that the expected cpu model can be faithfully handled by
KVM, rather than updating the cpu model to match KVM.
We call kvm_check_mmu() from the spapr cpu reset code. This is a hack:
conceptually it makes more sense where fixup_page_sizes() was - in the KVM
cpu init path. However, doing that would require moving the platform's
pagesize filtering much earlier, which would require a lot of work making
further adjustments. There wouldn't be a lot of concrete point to doing
that, since the only KVM implementation which has the awkward MMU
restrictions is KVM HV, which can only work with an spapr guest anyway.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
spapr capabilities have an apply hook to actually activate (or deactivate)
the feature in the system at reset time. However, a number of capabilities
affect the setup of cpus, and need to be applied to each of them -
including hotplugged cpus for extra complication. To make this simpler,
add an optional cpu_apply hook that is called from spapr_cpu_reset().
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
QEMU implements the "Shared Processor LPAR" (SPLPAR) option, which allows
the hypervisor to time-slice a physical processor into multiple virtual
processor. The intent is to allow more guests to run, and to optimize
processor utilization.
The guest OS can cede idle VCPUs, so that their processing capacity may
be used by other VCPUs, with the H_CEDE hcall. The guest OS can also
optimize spinlocks, by confering the time-slice of a spinning VCPU to the
spinlock holder if it's currently notrunning, with the H_CONFER hcall.
Both hcalls depend on a "Virtual Processor Area" (VPA) to be registered
by the guest OS, generally during early boot. Other per-VCPU areas can
be registered: the "SLB Shadow Buffer" which allows a more efficient
dispatching of VCPUs, and the "Dispatch Trace Log Buffer" (DTL) which
is used to compute time stolen by the hypervisor. Both DTL and SLB Shadow
areas depend on the VPA to be registered.
The VPA/SLB Shadow/DTL are state that QEMU should migrate, but this doesn't
happen, for no apparent reason other than it was just never coded. This
causes the features listed above to stop working after migration, and it
breaks the logic of the H_REGISTER_VPA hcall in the destination.
The VPA is set at the guest request, ie, we don't have to migrate
it before the guest has actually set it. This patch hence adds an
"spapr_cpu/vpa" subsection to the recently introduced per-CPU machine
data migration stream.
Since DTL and SLB Shadow are optional and both depend on VPA, they get
their own subsections "spapr_cpu/vpa/slb_shadow" and "spapr_cpu/vpa/dtl"
hanging from the "spapr_cpu/vpa" subsection.
Note that this won't break migration to older QEMUs. Is is already handled
by only registering the vmstate handler for per-CPU data with newer machine
types.
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
A per-CPU machine data pointer was recently added to PowerPCCPU. The
motivation is to to hide platform specific details from the core CPU
code. This per-CPU data can hold state which is relevant to the guest
though, eg, Virtual Processor Areas, and we should migrate this state.
This patch adds the plumbing so that we can migrate the per-CPU data
for PAPR guests. We only do this for newer machine types for the sake
of backward compatibility. No state is migrated for the moment: the
vmstate_spapr_cpu_state structure will be populated by subsequent
patches.
Signed-off-by: Greg Kurz <groug@kaod.org>
[dwg: Fix some trivial spelling and spacing errors]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
CPUPPCState currently contains a number of fields containing the state of
the VPA. The VPA is a PAPR specific concept covering several guest/host
shared memory areas used to communicate some information with the
hypervisor.
As a PAPR concept this is really machine specific information, although it
is per-cpu, so it doesn't really belong in the core CPU state structure.
There's also other information that's per-cpu, but platform/machine
specific. So create a (void *)machine_data in PowerPCCPU which can be
used by the machine to locate per-cpu data. Intialization, lifetime and
cleanup of machine_data is entirely up to the machine type.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Greg Kurz <groug@kaod.org>
This moves some code out from spapr_cpu_core_realize() for clarity. No
functional change.
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The spapr_realize_vcpu() function doesn't rollback in case of error.
This isn't a problem with coldplugged CPUs because the machine won't
start and QEMU will exit. Hotplug is a different story though: the
CPU thread is started under object_property_set_bool() and it assumes
it can access the CPU object.
If icp_create() fails, we return an error without unregistering the
reset handler for this CPU, and we let the underlying QEMU thread for
this CPU alive. Since spapr_cpu_core_realize() doesn't care to unrealize
already realized CPUs either, but happily frees all of them anyway, the
CPU thread crashes instantly:
(qemu) device_add host-spapr-cpu-core,core-id=1,id=gku
GKU: failing icp_create (cpu 0x11497fd0)
^^^^^^^^^^
Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7fffee3feaa0 (LWP 24725)]
0x00000000104c8374 in object_dynamic_cast_assert (obj=0x11497fd0,
^^^^^^^^^^^^^^
pointer to the CPU object
623 trace_object_dynamic_cast_assert(obj ? obj->class->type->name
(gdb) p obj->class->type
$1 = (Type) 0x0
(gdb) p * obj
$2 = {class = 0x10ea9c10, free = 0x11244620,
^^^^^^^^^^
should be g_free
(gdb) p g_free
$3 = {<text variable, no debug info>} 0x7ffff282bef0 <g_free>
obj is a dangling pointer to the CPU that was just destroyed in
spapr_cpu_core_realize().
This patch adds proper rollback to both spapr_realize_vcpu() and
spapr_cpu_core_realize().
Signed-off-by: Greg Kurz <groug@kaod.org>
[dwg: Fixed a conflict due to a change in my tree]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Commit 94ad93bd97 (QEMU 2.12) switched to instantiate CPUs separately
but it missed to adapt the error path accordingly. If something fails in
the CPU creation loop, then the CPU object that was just created is leaked.
The error paths in this function are a bit obfuscated, and adding
yet another label to free this CPU object makes it worse. We should
move the block of the loop to a separate function, with a proper
rollback path, but this is a bigger cleanup.
For now, let's just fix the bug by adding the missing calls to
object_unref(). This will allow easier backport to older QEMU
versions.
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
spapr_cpu_init() and spapr_cpu_destroy() are only called from the spapr
cpu core realize/unrealize paths, and really can only be called from there.
Those are all short functions, so fold the pairs together for simplicity.
While we're there rename some functions and change some parameter types
for brevity and clarity.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
To prevent spurious wakeups on cpus that are supposed to be disabled, we
need to clear the LPCR bits which control certain wakeup events.
spapr_cpu_reset() has separate cases here for boot and non-boot (initially
inactive) cpus. rtas_start_cpu() then turns the LPCR bits on when the
non-boot cpus are activated.
But explicit checks against first_cpu are not how we usually do things:
instead spapr_cpu_reset() generally sets things up for non-boot (inactive)
cpus, then spapr_machine_reset() and/or rtas_start_cpu() override as
necessary.
So, do that instead. Because the LPCR activation is identical for boot
cpus and non-boot cpus just activated with rtas_start_cpu() we can put the
code common in spapr_cpu_set_entry_state().
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Tested-by: Cédric Le Goater <clg@kaod.org>
cpu_ppc_set_papr() does several things:
1) it sets up the virtual hypervisor interface
2) it prevents the cpu from ever entering hypervisor mode
3) it tells KVM that we're emulating a cpu in PAPR mode
and 4) it configures the LPCR and AMOR (hypervisor privileged registers)
so that TCG will behave correctly for PAPR guests, without
attempting to emulate the cpu in hypervisor mode
(1) & (2) make sense for any virtual hypervisor (if another one ever
exists).
(3) belongs more properly in the machine type specific to a PAPR guest, so
move it to spapr_cpu_init(). While we're at it, remove an ugly test on
kvm_enabled() by making kvmppc_set_papr() a safe no-op on non-KVM.
(4) also belongs more properly in the machine type specific code. (4) is
done by mangling the default values of the SPRs, so that they will be set
correctly at reset time. Manipulating usually-static parameters of the cpu
model like this is kind of ugly, especially since the values used really
have more to do with the platform than the cpu.
The spapr code already has places for PAPR specific initializations of
register state in spapr_cpu_reset(), so move this handling there.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Tested-by: Cédric Le Goater <clg@kaod.org>
Under PAPR, only the boot CPU is active when the system starts. Other cpus
must be explicitly activated using an RTAS call. The entry state for the
boot and secondary cpus isn't identical, but it has some things in common.
We're going to add a bit more common setup later, too, so to simplify
make a helper which sets up the common entry state for both boot and
secondary cpu threads.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Tested-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Although the order doesn't really matter at the moment, it's possible
other initializastions could depend on the compatiblity mode, so make sure
we set it first in spapr_cpu_reset().
While we're at it drop the test against first_cpu. Setting the compat mode
to the value it already has is redundant, but harmless, so we might as well
make a small simplification to the code.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
The VCPU ids are currently computed and assigned to each individual
CPU threads in spapr_cpu_core_realize(). But the numbering logic
of VCPU ids is actually a machine-level concept, and many places
in hw/ppc/spapr.c also have to compute VCPU ids out of CPU indexes.
The current formula used in spapr_cpu_core_realize() is:
vcpu_id = (cc->core_id * spapr->vsmt / smp_threads) + i
where:
cc->core_id is a multiple of smp_threads
cpu_index = cc->core_id + i
0 <= i < smp_threads
So we have:
cpu_index % smp_threads == i
cc->core_id / smp_threads == cpu_index / smp_threads
hence:
vcpu_id =
(cpu_index / smp_threads) * spapr->vsmt + cpu_index % smp_threads;
This formula was used before VSMT at the time VCPU ids where computed
at the target emulation level. It has the advantage of being useable
to derive a VPCU id out of a CPU index only. It is fitted for all the
places where the machine code has to compute a VCPU id.
This patch introduces an accessor to set the VCPU id in a PowerPCCPU object
using the above formula. It is a first step to consolidate all the VCPU id
logic in a single place.
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Commit 51f84465dd changed the compatility mode setting logic:
- machine reset only sets compatibility mode for the boot CPU
- compatibility mode is set for other CPUs when they are put online
by the guest with the "start-cpu" RTAS call
This causes a regression for machines started with max-compat-cpu:
the device tree nodes related to secondary CPU cores contain wrong
"cpu-version" and "ibm,pa-features" values, as shown below.
Guest started on a POWER8 host with:
-smp cores=2 -machine pseries,max-cpu-compat=compat7
ibm,pa-features = [18 00 f6 3f c7 c0 80 f0 80 00
00 00 00 00 00 00 00 00 80 00 80 00 80 00 00 00];
cpu-version = <0x4d0200>;
^^^
second CPU core
ibm,pa-features = <0x600f63f 0xc70080c0>;
cpu-version = <0xf000003>;
^^^
boot CPU core
The second core is advertised in raw POWER8 mode. This happens because
CAS assumes all CPUs to have the same compatibility mode. Since the
boot CPU already has the requested compatibility mode, the CAS code
does not set it for the secondary one, and exposes the bogus device
tree properties in in the CAS response to the guest.
A similar situation is observed when hot-plugging a CPU core. The
related device tree properties are generated and exposed to guest
with the "ibm,configure-connector" RTAS before "start-cpu" is called.
The CPU core is advertised to the guest in raw mode as well.
It both cases, it boils down to the fact that "start-cpu" happens too
late. This can be fixed globally by propagating the compatibility mode
of the boot CPU to the other CPUs during reset. For this to work, the
compatibility mode of the boot CPU must be set before the machine code
actually resets all CPUs.
It is not needed to set the compatibility mode in "start-cpu" anymore,
so the code is dropped.
Fixes: 51f84465dd
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
applied using ./scripts/clean-includes
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
The 'intc' pointer of the CPU references the interrupt presenter in
the XICS interrupt mode. When the XIVE interrupt mode is available and
activated, the machine will need to reassign this pointer to reflect
the change.
Moving this assignment under the realize routine of the CPU will ease
the process when the interrupt mode is toggled.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The sPAPR and the PowerNV core objects create the interrupt presenter
object of the CPUs in a very similar way. Let's provide a common
routine in which we use the presenter 'type' as a child identifier.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Just like for hot unplug CPUs, when a guest is rebooted, the secondary
CPUs can be awaken by the decrementer and start entering SLOF at the
same time the boot CPU is.
To be safe, let's disable on the secondaries all the exceptions which
can cause an exit while the CPU is in power-saving mode.
Based on previous work from Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The current code assumes that only the CPU core object holds a
reference on each individual CPU object, and happily frees their
allocated memory when the core is unrealized. This is dangerous
as some other code can legitimely keep a pointer to a CPU if it
calls object_ref(), but it would end up with a dangling pointer.
Let's allocate all CPUs with object_new() and let QOM free them
when their reference count reaches zero. This greatly simplify the
code as we don't have to fiddle with the instance size anymore.
Signed-off-by: Greg Kurz <groug@kaod.org>
Acked-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This makes the code easier to understand and it is consistent with what
we already do for PHBs.
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
use generic cpu_model parsing introduced by
(6063d4c0f vl.c: convert cpu_model to cpu type and set of global properties before machine_init())
it allows to:
* replace sPAPRMachineClass::tcg_default_cpu with
MachineClass::default_cpu_type
* drop cpu_parse_cpu_model() from hw/ppc/spapr.c and reuse
one in vl.c
* simplify spapr_get_cpu_core_type() by removing
not needed anymore recurrsion since alias look up
happens earlier at vl.c and spapr_get_cpu_core_type()
works only with resulted from that cpu type.
* spapr no more needs to parse/depend on being phased out
MachineState::cpu_model, all tha parsing done by generic
code and target specific callback.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
[dwg: Correct minor compile error]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
consolidate 'host' core type registration by moving it from
KVM specific code into spapr_cpu_core.c, similar like it's
done in x86 target.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
replace sPAPRCPUCoreClass::cpu_class with cpu type name
since it were needed just to get that at points it were
accessed.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
spapr core type definition doesn't have any fields that
require it to be defined at runtime. So replace code
that fills in TypeInfo at runtime with static TypeInfo
array that does the same at complie time.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
there is a dedicated callback CPUClass::parse_features
which purpose is to convert -cpu features into a set of
global properties AND deal with compat/legacy features
that couldn't be directly translated into CPU's properties.
Create ppc variant of it (ppc_cpu_parse_featurestr) and
move 'compat=val' handling from spapr_cpu_core.c into it.
That removes a dependency of board/core code on cpu_model
parsing and would let to reuse common -cpu parsing
introduced by 6063d4c0
Set "max-cpu-compat" property only if it exists, in practice
it should limit 'compat' hack to spapr machine and allow
to avoid including machine/spapr headers in target/ppc/cpu.c
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
ppc_cpu_parse_features() is doing practically the same thing as
generic cpu_parse_cpu_model(). So remove duplicated impl. and
reuse generic one.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
At the moment the only POWER9 model which is listed in qemu is v1.0 (aka
"DD1"). This is a very early (read, buggy) version which will never be
released to the public - it was included in qemu only for the convenience
of those doing bringup on the early silicon. For bonus points, we actually
had its PVR incorrect in the table (0x004e0000 instead of 0x004e0100). We
also never actually implemented the differences in behaviour (read, bugs)
that marked DD1 in qemu.
Now that we know the PVR for the substantially better v2.0 (DD2) chip,
include it and make it the default POWER9 in qemu. For the time being we
leave the DD1 definition in place for the poor souls (read, me) who still
need to work with DD1 hardware.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
When running with KVM PR, if a new HPT is allocated we need to inform
KVM about the HPT address and size. This is currently done by hacking
the value of SDR1 and pushing it to KVM in several places.
Also, migration breaks the guest since it is very unlikely the HPT has
the same address in source and destination, but we push the incoming
value of SDR1 to KVM anyway.
This patch introduces a new virtual hypervisor hook so that the spapr
code can provide the correct value of SDR1 to be pushed to KVM each
time kvmppc_put_books_sregs() is called.
It allows to get rid of all the hacking in the spapr/kvmppc code and
it fixes migration of nested KVM PR.
Suggested-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This patch removes the qdev_get_machine() calls that are made
in spapr_cpu_core.c in situations where we can get an existing
pointer for the MachineState by either passing it as an argument
to the function or by using other already available pointers.
Credits to Daniel Henrique Barboza for the idea and the changelog
text.
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Since commit 7cca3e466e ("ppc: spapr: Move VCPU ID calculation into
sPAPR"), QEMU aborts when started with a *-spapr-cpu-core device and
a non-pseries machine.
Let's rely on the already existing call to object_dynamic_cast() instead
of using the SPAPR_MACHINE() macro.
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Move the calculation of a CPU's VCPU ID out of the generic PPC code
(ppc_cpu_realizefn()) and into sPAPR specific code
(spapr_cpu_core_realize()) where it belongs.
Unfortunately, due to the way things are ordered, we still need to
default the VCPU ID in ppc_cpu_realizfn() but at least doing that
doesn't require any interaction with sPAPR.
Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
PPC handles -cpu FOO rather incosistently,
i.e. it does case-insensitive matching of FOO to
a CPU type (see: ppc_cpu_compare_class_name) but
handles alias names as case-sensitive, as result:
# qemu-system-ppc64 -M mac99 -cpu g3
qemu-system-ppc64: unable to find CPU model ' kN�U'
# qemu-system-ppc64 -cpu 970MP_V1.1
qemu-system-ppc64: Unable to find sPAPR CPU Core definition
while
# qemu-system-ppc64 -M mac99 -cpu G3
# qemu-system-ppc64 -cpu 970MP_v1.1
start up just fine.
Considering we can't take case-insensitive matching away,
make it case-insensitive for all alias/type/core_type
lookups.
As side effect it allows to remove duplicate core types
which are the same except of using different cased letters in name.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
QEMU currently crashes when the user tries to add a spapr-cpu-core
on a non-pseries machine:
$ qemu-system-ppc64 -S -machine ppce500,accel=tcg \
-device POWER5+_v2.1-spapr-cpu-core
hw/ppc/spapr_cpu_core.c:178:spapr_cpu_core_realize_child:
Object 0x55cee1f55160 is not an instance of type spapr-machine
Aborted (core dumped)
So let's add a proper check for the correct machine time with
a more friendly error message here.
Reported-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
ICPState objects were being allocated before CPU thread realization.
However commit 9ed656631d (xics: setup cpu at realize time) reversed it
by allocating ICPState objects after CPU thread is realized. But it
didn't take care to fix the error path because of which we observe
a SIGSEGV when CPU thread realization fails during cold/hotplug.
Fix this by ensuring that we do object_unparent() of ICPState object
only in case when is was created earlier.
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Currently, the CPU compatibility mode is set when the cpu is initialized,
then again when the guest negotiates features. This means if a guest
negotiates a compatibility mode, then reboots, that compatibility mode
will be retained across the reset.
Usually that will get overridden when features are negotiated on the next
boot, but it's still not really correct. This patch moves the initial set
up of the compatibility mode from cpu init to reset time. The mode *is*
retained if the reboot was caused by the feature negotiation (it might
be important in that case, though it's unlikely).
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Tested-by: Andrea Bolognani <abologna@redhat.com>
Server class POWER CPUs have a "compat" property, which is used to set the
backwards compatibility mode for the processor. However, this only makes
sense for machine types which don't give the guest access to hypervisor
privilege - otherwise the compatibility level is under the guest's control.
To reflect this, this removes the CPU 'compat' property and instead
creates a 'max-cpu-compat' property on the pseries machine. Strictly
speaking this breaks compatibility, but AFAIK the 'compat' option was
never (directly) used with -device or device_add.
The option was used with -cpu. So, to maintain compatibility, this
patch adds a hack to the cpu option parsing to strip out any compat
options supplied with -cpu and set them on the machine property
instead of the now deprecated cpu property.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Greg Kurz <groug@kaod.org>
Tested-by: Andrea Bolognani <abologna@redhat.com>
Until recently, spapr used to allocate ICPState objects for the lifetime
of the machine. They would only be associated to vCPUs in xics_cpu_setup()
when plugging a CPU core.
Now that ICPState objects have the same lifecycle as vCPUs, it is
possible to associate them during realization.
This patch hence open-codes xics_cpu_setup() in icp_realize(). The vCPU
is passed as a property. Note that vCPU now needs to be realized first
for the IRQs to be allocated. It also needs to resetted before ICPState
realization in order to synchronize with KVM.
Since ICPState objects are freed when unrealized, xics_cpu_destroy() isn't
needed anymore and can be safely dropped.
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
These properties are part of the XICS API. They deserve to appear
explicitely in the XICS header file.
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Move vcpu's associated numa_node field out of generic CPUState
into inherited classes that actually care about cpu<->numa mapping,
i.e: ARMCPU, PowerPCCPU, X86CPU.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <1496161442-96665-6-git-send-email-imammedo@redhat.com>
[ehabkost: s/CPU is belonging to/CPU belongs to/ on comments]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
When a piece of code allocates an object, it implicitely gets a reference
on it. If it then makes that object a child property of another object, it
should drop its own reference at some point otherwise the child object can
never be finalized. The current code hence leaks one ICP object per CPU
when hot-removing a core.
Failing to add a newly allocated ICP object to the CPU is a bug. While here,
let's ensure QEMU aborts if this ever happens.
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
While here we introduce a single error path to avoid code duplication.
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
it's safe to remove thread node_id != core node_id error
branch as machine_set_cpu_numa_node() also does mismatch
check and is called even before any CPU is created.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <1494415802-227633-10-git-send-email-imammedo@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
it will allow switching from cpu_index to core based numa
mapping in follow up patches.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <1494415802-227633-3-git-send-email-imammedo@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Recent commits that re-organized ICPState object missed to destroy
the object when CPU is unrealized. Fix this so that CPU unplug
doesn't abort QEMU.
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Today, all the ICPs are created before the CPUs, stored in an array
under the sPAPR machine and linked to the CPU when the core threads
are realized. This modeling brings some complexity when a lookup in
the array is required and it can be simplified by allocating the ICPs
when the CPUs are.
This is the purpose of this proposal which introduces a new 'icp_type'
field under the machine and creates the ICP objects of the right type
(KVM or not) before the PowerPCCPU object are.
This change allows more cleanups : the removal of the icps array under
the sPAPR machine and the removal of the xics_get_cpu_index_by_dt_id()
helper.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This is the second step to abstract the IRQ 'server' number of the
XICS layer. Now that the prereq cleanups have been done in the
previous patch, we can move down the 'cpu_dt_id' to 'cpu_index'
mapping in the sPAPR machine handler.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Today, the ICPState array of the sPAPR machine is indexed with
'cpu_index' of the CPUState. This numbering of CPUs is internal to
QEMU and the guest only knows about what is exposed in the device
tree, that is the 'cpu_dt_id'. This is why sPAPR uses the helper
xics_get_cpu_index_by_dt_id() to do the mapping in a couple of places.
To provide a more generic XICS layer, we need to abstract the IRQ
'server' number and remove any assumption made on its nature. It
should not be used as a 'cpu_index' for lookups like xics_cpu_setup()
and xics_cpu_destroy() do.
To reach that goal, we choose to introduce a generic 'intc' backlink
under PowerPCCPU, and let the machine core init routine do the
ICPState lookup. The resulting object is passed on to xics_cpu_setup()
which does the store under PowerPCCPU. The IRQ 'server' number in XICS
is now generic. sPAPR uses 'cpu_dt_id' and PowerNV will use 'PIR'
number.
This also has the benefit of simplifying the sPAPR hcall routines
which do not need to do any ICPState lookups anymore.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Threads within a core shouldn't be on different
NUMA nodes, so if user has misconfgured command
line, fail QEMU at start up to force user fix it.
For now use the first thread on the core as source
of core's node-id. Later when cpu-numa refactoring
lands it will be switched to core's node-id from
possible_cpus[].
This prevents the same problems as commit 20bb648d
"spapr: Fix default NUMA node allocation for threads",
but for the case of manually configured NUMA node
mappings, instead of just the default case.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
