On 2022/7/6 上午2:45, Rafael J. Wysocki wrote:
On Fri, Jul 1, 2022 at 9:05 AM Tony W Wang-oc <TonyWWang-oc@xxxxxxxxxxx> wrote:The original commit 991528d73486 ("ACPI: Processor native C-states using MWAIT") has a vendor check for Intel in the function of ffh_cstate_init(). Commit 5209654a46ee ("x86/ACPI/cstate: Allow ACPI C1 FFH MWAIT use on AMD systems") and commit 280b68a3b3b9 ("x86/cstate: Allow ACPI C1 FFH MWAIT use on Hygon systems") add vendor check for AMD and HYGON in the function of ffh_cstate_init(). Recent Zhaoxin and Centaur CPUs support MONITOR/MWAIT instructions that can be used for ACPI Cx state in the same way as Intel. So expected to add the support of these CPUs in the function of ffh_cstate_init() too. The CPU feature X86_FEATURE_MWAIT indicates processor supports MONITOR/ MWAIT instructions. So the check for many CPU vendors in ffh_cstate_init() is unnecessary, use X86_FEATURE_MWAIT to replace the CPU vendor check. Signed-off-by: Tony W Wang-oc <TonyWWang-oc@xxxxxxxxxxx>Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Thanks a lot. Add some original commit authors this patch related to.
or please let me know if I'm expected to pick up this one. Thanks!
Yes for me. Thanks a lot.
--- arch/x86/kernel/acpi/cstate.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) diff --git a/arch/x86/kernel/acpi/cstate.c b/arch/x86/kernel/acpi/cstate.c index 7945eae..a64c38f 100644 --- a/arch/x86/kernel/acpi/cstate.c +++ b/arch/x86/kernel/acpi/cstate.c @@ -209,11 +209,7 @@ EXPORT_SYMBOL_GPL(acpi_processor_ffh_cstate_enter); static int __init ffh_cstate_init(void) { - struct cpuinfo_x86 *c = &boot_cpu_data; - - if (c->x86_vendor != X86_VENDOR_INTEL && - c->x86_vendor != X86_VENDOR_AMD && - c->x86_vendor != X86_VENDOR_HYGON) + if (!boot_cpu_has(X86_FEATURE_MWAIT)) return -1; cpu_cstate_entry = alloc_percpu(struct cstate_entry); -- 2.7.4.
