* Michael Ellerman <m...@ellerman.id.au> [2017-08-24 20:28:19]: > Vaidyanathan Srinivasan <sva...@linux.vnet.ibm.com> writes: > > > On PowerNV platforms, firmware provides exit latency and > > target residency for each of the idle states in nano > > seconds. Cpuidle framework expects the values in micro > > seconds. Round up to nearest micro seconds to avoid errors > > in cases where the values are defined as fractional micro > > seconds. > > > > Default idle state of 'snooze' has exit latency of zero. If > > other states have fractional micro second exit latency, they > > would get rounded down to zero micro second and make cpuidle > > framework choose deeper idle state when snooze loop is the > > right choice. > > > > Reported-by: Anton Blanchard <an...@samba.org> > > Signed-off-by: Vaidyanathan Srinivasan <sva...@linux.vnet.ibm.com> > > This sounds like a fairly bad bug, does it need a Fixes / Cc stable tag?
Yes, we will need this on stable kernel that runs on POWER9. On older platforms the latencies are larger and hence no impact :) I will post to stable after this fix hits your -next tree. --Vaidy