Making a VPE resident on GICv4.1 is pretty simple, as it is just a
single write to the local redistributor. We just need extra information
about which groups to enable, which the KVM code will have to provide.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20191224111055.11836-12-maz@kernel.org
The ITS VMAPP command gains some new fields with GICv4.1:
- a default doorbell, which allows a single doorbell to be used for
all the VLPIs routed to a given VPE
- a pointer to the configuration table (instead of having it in a register
that gets context switched)
- a flag indicating whether this is the first map or the last unmap for
this particular VPE
- a flag indicating whether the pending table is known to be zeroed, or not
Plumb in the new fields in the VMAPP builder, and add the map/unmap
refcounting so that the ITS can do the right thing.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20191224111055.11836-7-maz@kernel.org
In order to find out whether a vcpu is likely to be the target of
VLPIs (and to further optimize the way we deal with those), let's
track the number of VLPIs a vcpu can receive.
This gets implemented with an atomic variable that gets incremented
or decremented on map, unmap and move of a VLPI.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Link: https://lore.kernel.org/r/20191107160412.30301-2-maz@kernel.org
When the VHE code was reworked, a lot of the vgic stuff was moved around,
but the GICv4 residency code did stay untouched, meaning that we come
in and out of residency on each flush/sync, which is obviously suboptimal.
To address this, let's move things around a bit:
- Residency entry (flush) moves to vcpu_load
- Residency exit (sync) moves to vcpu_put
- On blocking (entry to WFI), we "put"
- On unblocking (exit from WFI), we "load"
Because these can nest (load/block/put/load/unblock/put, for example),
we now have per-VPE tracking of the residency state.
Additionally, vgic_v4_put gains a "need doorbell" parameter, which only
gets set to true when blocking because of a WFI. This allows a finer
control of the doorbell, which now also gets disabled as soon as
it gets signaled.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20191027144234.8395-2-maz@kernel.org
Based on 1 normalized pattern(s):
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distributed in the hope that it will be useful but without any
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has been chosen to replace the boilerplate/reference in 503 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Enrico Weigelt <info@metux.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In some randconfig scenarios, including arm-gic-v4.h results
in a spurious wawrning about the $SUBJECT structure not being
defined. Adding a forward definition keeps it quiet.
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
So far, we require the hypervisor to update the VLPI properties
once the the VLPI mapping has been established. While this
makes it easy for the ITS driver, it creates a window where
an incoming interrupt can be delivered with an unknown set
of properties. Not very nice.
Instead, let's add a "properties" field to the mapping structure,
and use that to configure the VLPI before it actually gets mapped.
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
So far, we map all VPEs on all ITSs. While this is not wrong,
this is quite a big hammer, as moving a VPE around requires
all ITSs to be synchronized. Needles to say, this is an
expensive proposition.
Instead, let's switch to a mode where we issue VMAPP commands
only on ITSs that are actually involved in reporting interrupts
to the given VM.
For that purpose, we refcount the number of interrupts are are
mapped for this VM on each ITS, performing the map/unmap
operations as required. It then allows us to use this refcount
to only issue VMOVP to the ITSs that need to know about this
VM.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
As we're about to make use of the maximum number of ITSs in
a GICv4 system, let's make this value global (and rename it to
GICv4_ITS_LIST_MAX).
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Add the required interfaces to map, unmap and update a VLPI.
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Add the required interfaces to schedule a VPE and perform a
VINVALL command.
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
When creating a VM, it is very convenient to have an irq domain
containing all the doorbell interrupts associated with that VM
(each interrupt representing a VPE).
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
When we don't have the DirectLPI feature, we must work around the
architecture shortcomings to be able to perform the required
maintenance (interrupt masking, clearing and injection).
For this, we create a fake device whose sole purpose is to
provide a way to issue commands as if we were dealing with LPIs
coming from that device (while they actually originate from
the ITS). This fake device doesn't have LPIs allocated to it,
but instead uses the VPE LPIs.
Of course, this could be a real bottleneck, and a naive
implementation would require 6 commands to issue an invalidation.
Instead, let's allocate at least one event per physical CPU
(rounded up to the next power of 2), and opportunistically
map the VPE doorbell to an event. This doorbell will be mapped
until we roll over and need to reallocate this slot.
This ensures that most of the time, we only need 2 commands
to issue an INV, INT or CLEAR, making the performance a lot
better, given that we always issue a CLEAR on entry, and
an INV on each side of a trapped WFI.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Add a bunch of GICv4-specific data structures that will get used in
subsequent patches.
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
