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Revision 55f7d4b0

ID55f7d4b09e0bd1f6e5875fe0a5a58852999e4e92

Added by David Gibson over 12 years ago

ppc: Avoid decrementer related kvm exits

In __cpu_ppc_store_decr(), we set up a regular timer used to trigger
decrementer interrupts. This is necessary to implement the decrementer
properly under TCG, but is unnecessary under KVM (true for both Book3S-PR
and Book3S-HV KVM variants), because the kernel handles generating and
delivering decrementer exceptions.

Under kvm, in fact, the timer causes expensive and unnecessary exits from
kvm to qemu. This patch, therefore, disables setting the timer when kvm
is in use.

Signed-off-by: Anton Blanchard <>
Signed-off-by: David Gibson <>
Signed-off-by: Alexander Graf <>

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