On Monday, July 31, 2017 04:46:42 PM Doug Smythies wrote: > On 2017.07.28 05:45 Rafael J. Wysocki wrote: > > > From: Rafael J. Wysocki <rafael.j.wyso...@intel.com> > > > > After commit f8475cef9008 "x86: use common aperfmperf_khz_on_cpu() to > > calculate KHz using APERF/MPERF" the scaling_cur_freq policy attribute > > in sysfs only behaves as expected on x86 with APERF/MPERF registers > > available when it is read from at least twice in a row. The value > > returned by the first read may not be meaningful, because the > > computations in there use cached values from the previous iteration > > of aperfmperf_snapshot_khz() which may be stale. > > > > To prevent that from happening, modify arch_freq_get_on_cpu() to > > call aperfmperf_snapshot_khz() twice, with a short delay between > > these calls, if the previous invocation of aperfmperf_snapshot_khz() > > was too far back in the past (specifically, more that 1s ago). > > ...[deleted the rest]... > > This patch seems to work fine and addresses my complaints from last week. > Thanks.
Thanks for the confirmation! Rafael
