Don't do random() when not needed
Don't do random() when not needed

This can shave off up to 10ns from message passing latency

Signed-off-by: Martin Sustrik <4dd6061be1198639e8b05ce4fd5ead7a0dcaa0f4@250bpm.com>

reqshark/libmill,dailypips/libmill,sustrik/libmill,jimjag/mill,acornejo/libmill,linearregression/libmill,lsm/libmill,jimjag/mill,lsm/libmill,ebfe/libmill,linearregression/libmill,dailypips/libmill,8l/libmill,lsm/libmill,nirs/libmill,reqshark/libmill,nirs/libmill,reqshark/libmill,dailypips/libmill,jimjag/mill,ebfe/libmill,sustrik/libmill,sustrik/libmill,acornejo/libmill,8l/libmill,linearregression/libmill,ebfe/libmill