KVM: arm64: vgic-v4: Move the GICv4 residency flow to be driven by vcpu_load/put

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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

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This commit is contained in:

Marc Zyngier 2019-10-27 14:41:59 +00:00

parent 5c40130801

commit 8e01d9a396

8 changed files with 48 additions and 42 deletions

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4

include/kvm/arm_vgic.h

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2

include/linux/irqchip/arm-gic-v4.h

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