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>
Add POWER9 cpu to list of spapr core models which allows it to be specified
as the cpu model for a pseries guest (e.g. -machine pseries -cpu POWER9).
This now allows a POWER9 cpu to boot to userspace in tcg emulation for a
pseries machine with a legacy kernel.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Also introduce a xics_icp_get() helper to simplify the changes.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The pseries machine type implements the behaviour of a PAPR compliant
hypervisor, without actually executing such a hypervisor on the virtual
CPU. To do this we need some hooks in the CPU code to make hypervisor
facilities get redirected to the machine instead of emulated internally.
For hypercalls this is managed through the cpu->vhyp field, which points
to a QOM interface with a method implementing the hypercall.
For the hashed page table (HPT) - also a hypervisor resource - we use an
older hack. CPUPPCState has an 'external_htab' field which when non-NULL
indicates that the HPT is stored in qemu memory, rather than within the
guest's address space.
For consistency - and to make some future extensions easier - this merges
the external HPT mechanism into the vhyp mechanism. Methods are added
to vhyp for the basic operations the core hash MMU code needs: map_hptes()
and unmap_hptes() for reading the HPT, store_hpte() for updating it and
hpt_mask() to retrieve its size.
To match this, the pseries machine now sets these vhyp fields in its
existing vhyp class, rather than reaching into the cpu object to set the
external_htab field.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
cpu_ppc_set_papr() sets up various aspects of CPU state for use with PAPR
paravirtualized guests. However, it doesn't set the virtual hypervisor,
so callers must also call cpu_ppc_set_vhyp() so that PAPR hypercalls are
handled properly. This is a bit silly, so fold setting the virtual
hypervisor into cpu_ppc_set_papr().
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
spapr_core_pre_plug/spapr_core_plug/spapr_core_unplug() are managing
wiring CPU core into spapr machine state and not internal CPU core state.
So move them from spapr_cpu_core.c to spapr.c where other similar
(spapr_memory_[foo]plug()) callbacks are located, which also matches
x86 target practice.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Split off destroying VCPU threads from drc callback
spapr_core_release() into new spapr_cpu_core_unrealizefn()
which takes care of internal cpu core state cleanup (i.e.
VCPU threads) and is called when object_unparent(core)
is called.
That leaves spapr_core_release() only with board mgmt
code, which will be moved to board related file in
follow up patch along with the rest on hotplug callbacks.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The pseries machine type is a bit unusual in that it runs a paravirtualized
guest. The guest expects to interact with a hypervisor, and qemu
emulates the functions of that hypervisor directly, rather than executing
hypervisor code within the emulated system.
To implement this in TCG, we need to intercept hypercall instructions and
direct them to the machine's hypercall handlers, rather than attempting to
perform a privilege change within TCG. This is controlled by a global
hook - cpu_ppc_hypercall.
This cleanup makes the handling a little cleaner and more extensible than
a single global variable. Instead, each CPU to have hypercalls intercepted
has a pointer set to a QOM object implementing a new virtual hypervisor
interface. A method in that interface is called by TCG when it sees a
hypercall instruction. It's possible we may want to add other methods in
future.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Currently the pseries machine has two paths for constructing CPUs. On
newer machine type versions, which support cpu hotplug, it constructs
cpu core objects, which in turn construct CPU threads. For older machine
versions it individually constructs the CPU threads.
This division is going to make some future changes to the cpu construction
harder, so this patch unifies them. Now cpu core objects are always
created. This requires some updates to allow core objects to be created
without a full complement of threads (since older versions allowed a
number of cpus not a multiple of the threads-per-core). Likewise it needs
some changes to the cpu core hot/cold plug path so as not to choke on the
old machine types without hotplug support.
For good measure, we move the cpu construction to its own subfunction,
spapr_init_cpus().
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
We've currently got 18 architectures in QEMU, and thus 18 target-xxx
folders in the root folder of the QEMU source tree. More architectures
(e.g. RISC-V, AVR) are likely to be included soon, too, so the main
folder of the QEMU sources slowly gets quite overcrowded with the
target-xxx folders.
To disburden the main folder a little bit, let's move the target-xxx
folders into a dedicated target/ folder, so that target-xxx/ simply
becomes target/xxx/ instead.
Acked-by: Laurent Vivier <laurent@vivier.eu> [m68k part]
Acked-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> [tricore part]
Acked-by: Michael Walle <michael@walle.cc> [lm32 part]
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> [s390x part]
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> [s390x part]
Acked-by: Eduardo Habkost <ehabkost@redhat.com> [i386 part]
Acked-by: Artyom Tarasenko <atar4qemu@gmail.com> [sparc part]
Acked-by: Richard Henderson <rth@twiddle.net> [alpha part]
Acked-by: Max Filippov <jcmvbkbc@gmail.com> [xtensa part]
Reviewed-by: David Gibson <david@gibson.dropbear.id.au> [ppc part]
Acked-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com> [crisµblaze part]
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> [unicore32 part]
Signed-off-by: Thomas Huth <thuth@redhat.com>
spapr_finalize_fdt() both finishes building the device tree for the guest
and loads it into guest memory. For future cleanups, it's going to be
more convenient to do these two things separately. The loading portion is
pretty trivial, so we move it inline into the caller, ppc_spapr_reset().
We also rename spapr_finalize_fdt(), because the current name is going to
become inaccurate.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Replace repeated pattern
for (i = 0; i < nb_numa_nodes; i++) {
if (test_bit(idx, numa_info[i].node_cpu)) {
...
break;
with a helper function to lookup numa node index for cpu.
Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
If the user passes an alias name and a property to -cpu, QEMU fails to
find the CPU definition and exits.
$ qemu-system-ppc64 -cpu POWER8E,compat=power7
qemu-system-ppc64: Unable to find sPAPR CPU Core definition
This happens because spapr_get_cpu_core_type() passes the full string from
the command line (i.e. "POWER8E,compat=power7") to ppc_cpu_lookup_alias(),
instead of the alias name piece only (i.e. "POWER8E").
The fix is to pass model_pieces[0] to ppc_cpu_lookup_alias().
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Each spapr cpu core type defines an instance_init routine which just
populates the CPU class name. This can be done in the class_init
commonly for all core types which simplifies the registration.
This is inspired by how PowerNV core types are registered.
Certain types of spapr cpu cores ('host' and generic type based on host
CPU) are initialized in target-ppc/kvm.c. To convert these type
registrations to use class_init, we need to expose
spapr_cpu_core_class_init() outside of spapr_cpu_core.c.
Commit d11b268e17 added a generic sPAPR CPU core family
type to support cases like POWER8 CPU type on POWER8E host CPU.
Switching to class_init would fix such scenarios to use the right
CPU thread type instead of defaulting to host-powerpc64-cpu.
In an unrelated cleanup, fix a typo in .get_hotplug_handler routine.
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Hard-coding the CPU alias names in the spapr_cores[] array has
two big disadvantages:
1) We register a real type with the CPU alias name in
spapr_cpu_core_register_types() - this prevents us from registering
a CPU family name in kvm_ppc_register_host_cpu_type() with the same
name (as we do it for the non-hotpluggable CPU types).
2) It's quite cumbersome to maintain the aliases here in sync with the
ppc_cpu_aliases list from target-ppc/cpu-models.c.
So let's simply add proper alias lookup to the spapr cpu core code,
too (by checking whether the given model can be used directly, and
if not by trying to look up the given model as an alias name instead).
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Commit 9af9e0f, 6daf194d, be62a2eb and 312fd5f got rid of a bunch, but
they keep coming back. checkpatch.pl tries to flag them since commit
5d596c2, but it's not very good at it. Offenders tracked down with
Coccinelle script scripts/coccinelle/err-bad-newline.cocci, an updated
version of the script from commit 312fd5f.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1470224274-31522-2-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Prior to c8721d3 "spapr: Error out when CPU hotplug is attempted on older
pseries machines", attempting to use query-hotpluggable-cpus on pseries-2.6
and earlier machine types would SEGV.
That change fixed that, but due to some unexpected interactions in init
order and a brown-paper-bag worthy failure to test, it accidentally
disabled query-hotpluggable-cpus for all pseries machine types, including
the current one which should allow it.
In fact, query_hotpluggable_cpus needs to be non-NULL when and only when
the dr_cpu_enabled flag in sPAPRMachineClass is set, which makes
dr_cpu_enabled itself redundant.
This patch removes dr_cpu_enabled, instead directly setting
query_hotpluggable_cpus from the machine class_init functions, and using
that to determine the availability of CPU hotplug when necessary.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
CPU hotplug and coldplug aren't supported prior to pseries-2.7. Further,
earlier machine types don't use CPU core objects at all. These mean that
query-hotpluggable-cpus and coldplug on older pseries machines will crash
QEMU. It also means that hotpluggable_cpus flag in query-machines will
be incorrectly set to true for pseries < 2.7, since it is based on the
presence of the query_hotpluggable_cpus hook.
- Don't assign the query_hotpluggable_cpus hook for pseries < 2.7
- query_hotpluggable_cpus should therefore never be called on pseries <
2.7, so add an assert
- spapr_core_pre_plug() should fail hot/cold plug attempts for pseries <
2.7, since core objects are never used there
- spapr_core_plug() should therefore never be called for pseries < 2.7, so
add an assert.
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
[dwg: Change from query_hotpluggable_cpus returning NULL for pseries < 2.7
to not being called at all, reword commit message for accuracy]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Boot CPU is assumed to be always present in QEMU code. So
until that assumptions are gone, deny removal request.
In another words, QEMU won't support boot CPU core hot-unplug.
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
[dwg: Tweaked error message for clarity]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This reverts commit 5cbc64de25.
Now that we have stable cpu_index values for pseries-2.7 (and future)
machine types, we can now safely allow hotplug and unplug in any order.
Conflicts:
hw/ppc/spapr_cpu_core.c
Some conflicts on revert due to some small changes in the inserted
code since the original commit.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
It will enshure that cpu_index for a given cpu stays the same
regardless of the order cpus has been created/deleted and so
it would be possible to migrate QEMU instance with out of order
created CPU.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The goal of this patch is to have a stable core-id which does not depend
on any DT related semantics, which involve non-obvious computations on
modern PowerPC server cpus.
With this patch, the DT core id is computed on-demand as:
(core-id / smp_threads) * smt
where smt is the number of threads per core in the host.
This formula should be consolidated in a helper since it is needed in
several places.
Other uses for core-id includes: compute a stable cpu_index (which
allows random order hotplug/unplug without breaking migration) and
NUMA.
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
If CPU core addition or removal is allowed in random order leading to
holes in the core id range (and hence in the cpu_index range), migration
can fail as migration with holes in cpu_index range isn't yet handled
correctly.
Prevent this situation by enforcing the addition in contiguous order
and removal in LIFO order so that we never end up with holes in
cpu_index range.
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
If the host has 8 threads/core and the guest is started with:
-smp cores=1,threads=4,maxcpus=12
It is possible to crash QEMU by doing:
(qemu) device_add host-spapr-cpu-core,core-id=16,id=foo
(qemu) device_del foo
Segmentation fault
This happens because spapr_core_unplug() assumes cpu_dt_id == core_id.
As long as cpu_dt_id is derived from the non-table cpu_index, this is
only true when you plug cores with contiguous ids.
It is safer to be consistent: the DR connector was created with an
index that is immediately written to cc->core_id, and spapr_core_plug()
also relies on cc->core_id.
Let's use it also in spapr_core_unplug().
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Tracked down with an ugly, brittle and probably buggy Perl script.
Also move includes converted to <...> up so they get included before
ours where that's obviously okay.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
During CPU core realization, we create all the thread objects and parent
them to the core object in a loop. However, the realization of thread
objects is done separately by walking the threads of a core using
object_child_foreach(). With this, there is no guarantee on the order
in which the child thread objects get realized. Since CPU device tree
properties are currently derived from the CPU thread object, we assume
thread0 of the core to be the representative thread of the core when
creating device tree properties for the core. If thread0 is not the
first thread that gets realized, then we would end up having an
incorrect dt_id for the core and this causes hotplug failures from
the guest.
Fix this by realizing each thread object by walking the core's thread
object list thereby ensuring that thread0 and other threads are always
realized in the correct order.
Future TODO: CPU DT nodes are per-core properties and we should
ideally base the creation of CPU DT nodes on core objects rather than
the thread objects.
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>
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This patch changes spapr_cpu_core_realize_child() to have a local error
pointer and use error_propagate() as it is supposed to be done.
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
When a core is being realized, we create a child object for each thread
of the core.
The child is first initialized with object_initialize() which sets its ref
count to 1, and then added to the core with object_property_add_child()
which bumps the ref count to 2.
When the core gets released, object_unparent() decreases the ref count to 1,
and we g_free() the object: we hence loose the reference on an unfinalized
object. This is likely to cause random crashes.
Let's drop the extra reference as soon as we don't need it, after the
thread is added to the core.
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Introduction of core based CPU hotplug for PowerPC sPAPR didn't
add support for 970MP and POWER8NVL based core types. Add support for
the same.
While we are here, add support for explicit specification of POWER5+_v2.1
core type.
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The "ICP" is a different object than the "XICS". For historical reasons,
we have a number of places where we name a variable "icp" while it contains
a XICSState pointer. There *is* an ICPState structure too so this makes
the code really confusing.
This is a mechanical replacement of all those instances to use the name
"xics" instead. There should be no functional change.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[spapr_cpu_init has been moved to spapr_cpu_core.c, change there]
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
