On 03/05/2012 10:02 AM, Alexander Graf wrote: > @@ -442,6 +444,7 @@ heavyweight_exit: > > /* Return to kvm_vcpu_run(). */ > mtlr r5 > + mtcr r6 > addi r1, r1, HOST_STACK_SIZE > /* r3 still contains the return code from kvmppc_handle_exit(). */ > blr > @@ -459,6 +462,9 @@ _GLOBAL(__kvmppc_vcpu_run) > mflr r3 > PPC_STL r3, HOST_STACK_LR(r1) > > + mfcr r5 > + stw r5, HOST_CR(r1)
If you move the mfcr before the PPC_STL they should be able to run in parallel. Otherwise on e500mc mfcr will wait for PPC_STL to take its 3 cycles and then mfcr will take 5 cyles before the stw of HOST_CR. Alternatively, consider using mcrf/mtocrf three times. Similar issues in booke_interrupts.S (except we can't assume mtocrf exists there), but I'm less worried about that one as it still needs an optimization pass in general. -Scott -- To unsubscribe from this list: send the line "unsubscribe kvm-ppc" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
