On Tue, Jul 07, 2020 at 09:36:15AM -0700, Andy Lutomirski wrote: > On Mon, Jul 6, 2020 at 7:21 PM Cathy Zhang <cathy.zhang@xxxxxxxxx> wrote: > > > > This instruction gives software a way to force the processor to complete > > all modifications to flags, registers and memory from previous instructions > > and drain all buffered writes to memory before the next instruction is > > fetched and executed. > > > > The same effect can be obtained using the cpuid instruction. However, > > cpuid causes modification on the eax, ebx, ecx, and ecx regiters; it > > also causes a VM exit. > > > > A processor supports SERIALIZE instruction if CPUID.0x0x.0x0:EDX[14] is > > present. The CPU feature flag is shown as "serialize" in /proc/cpuinfo. > > > > Detailed information on the instructions and CPUID feature flag SERIALIZE > > can be found in the latest Intel Architecture Instruction Set Extensions > > and Future Features Programming Reference and Intel 64 and IA-32 > > Architectures Software Developer's Manual. > > Can you also wire this up so sync_core() uses it? I am cc'ing Fenghua, who has volunteered to work on this. Addind support for SERIALIZE in sync_core() should not block merging these patches, correct? Thanks and BR, Ricardo
