In the Intel® 64 and IA-32 Architectures Software Developer’s Manual Volume 3B page 14-4, it says:
"System software can temporarily disengage opportunistic processor performance operation by setting bit 32 of the IA32_PERF_CTL MSR (0199H), using a read-modify-write sequence on the MSR. The opportunistic processor performance operation can be re-engaged by clearing bit 32 in IA32_PERF_CTL MSR, using a read-modify-write sequence. The DISENAGE bit in IA32_PERF_CTL is not reflected in bit 32 of the IA32_PERF_STATUS MSR (0198H), and it is not shared between logical processors in a physical package."
It is the last sentence that concerns me. How do I disable opportunistic processor performance for all processors at once?