[PATCH][RFC] cpufreq: intel_pstate: Avoid time-costly synchronization if schedutil is not enabled

From: Chen Yu Commit bb6ab52f2bef ("intel_pstate: Do not set utilization update hook too early") moved the assignment of utilization update hook from intel_pstate_init_cpu to intel_pstate_set_policy(), however after moving, we need to leverage synchronize_sched() to deal with synchronization, whi

[PATCH] x86, tsc: Fix tsc ratio calibration to avoid broken mdelay

From: Chen Yu Currently we fetch the tsc radio by: ratio = (lo >> 8) & 0x1f; thus get bit8~bit12 of the MSR_PLATFORM_INFO, however according to Intel 64 and IA-32 Architectures Software Developer Manual 35.5, the ratio bit should be bit8~bit15, otherwise we might get incorrect tsc ratio and cause