[PATCH v6 14/15] KVM: arm64: Fold redundant exit code checks out of fixup_guest_exit()

Marc Zyngier marc.zyngier at arm.com
Wed May 9 02:05:43 PDT 2018


On 08/05/18 17:44, Dave Martin wrote:
> The entire tail of fixup_guest_exit() is contained in if statements
> of the form if (x && *exit_code == ARM_EXCEPTION_TRAP).  As a result,
> we can check just once and bail out of the function early, allowing
> the remaining if conditions to be simplified.
> 
> The only awkward case is where *exit_code is changed to
> ARM_EXCEPTION_EL1_SERROR in the case of an illegal GICv2 CPU
> interface access: in that case, the GICv3 trap handling code is
> skipped using a goto.  This avoids pointlessly evaluating the
> static branch check for the GICv3 case, even though we can't have
> vgic_v2_cpuif_trap and vgic_v3_cpuif_trap true simultaneously
> unless we have a GICv3 and GICv2 on the host: that sounds stupid,
> but I haven't satisfied myself that it can't happen.
> 
> No functional change.
> 
> Signed-off-by: Dave Martin <Dave.Martin at arm.com>

Reviewed-by: Marc Zyngier <marc.zyngier at arm.com>

	M.
-- 
Jazz is not dead. It just smells funny...



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