From: Christian Borntraeger <borntraeger@xxxxxxxxxx> Date: Fri, 21 Oct 2016 13:58:53 +0200 > For spinning loops people did often use barrier() or cpu_relax(). > For most architectures cpu_relax and barrier are the same, but on > some architectures cpu_relax can add some latency. For example on s390 > cpu_relax gives up the time slice to the hypervisor. On power cpu_relax > tries to give some of the CPU to the neighbor threads. To reduce the > latency another variant cpu_relax_lowlatency was introduced. Before this > is used in more and more places, lets revert the logic of provide a new > function cpu_relax_yield that can spend some time and for s390 yields > the guest CPU. Sparc64, fwiw, behaves similarly to powerpc. -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
