On 21/10/16 14:05, Peter Zijlstra wrote: > On Fri, Oct 21, 2016 at 01:58:55PM +0200, Christian Borntraeger wrote: >> stop_machine can take a very long time if the hypervisor does >> overcommitment for guest CPUs. When waiting for "the one", lets >> give up our CPU by using the new cpu_relax_yield. > > This seems something that would apply to most other virt stuff. Lets Cc > a few more lists for that. Corrected xen-devel mail address. Juergen > >> Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx> >> --- >> kernel/stop_machine.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c >> index ec9ab2f..1eb8266 100644 >> --- a/kernel/stop_machine.c >> +++ b/kernel/stop_machine.c >> @@ -194,7 +194,7 @@ static int multi_cpu_stop(void *data) >> /* Simple state machine */ >> do { >> /* Chill out and ensure we re-read multi_stop_state. */ >> - cpu_relax(); >> + cpu_relax_yield(); >> if (msdata->state != curstate) { >> curstate = msdata->state; >> switch (curstate) { >> -- >> 2.5.5 >> > _______________________________________________ > Virtualization mailing list > Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx > https://lists.linuxfoundation.org/mailman/listinfo/virtualization > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html