>>>>Hi, >>>> >>>>I am using this tool for querying VMX capabilities. >>>> >>>>http://git.qemu.org/?p=qemu.git;a=blob_plain;f=scripts/kvm/vmxcap;hb=HEAD >>>> >>>>And it shows as below that pause-loop exiting is not enabled. My kernel is >>>>3.14. >>>> >>>>secondary processor-based controls >>>> Virtualize APIC accesses yes >>>> Enable EPT yes >>>> Descriptor-table exiting yes >>>> Enable RDTSCP yes >>>> Virtualize x2APIC mode yes >>>> Enable VPID yes >>>> WBINVD exiting yes >>>> Unrestricted guest no >>>> APIC register emulation no >>>> Virtual interrupt delivery no >>>> PAUSE-loop exiting no >>>> RDRAND exiting no >>>> Enable INVPCID no >>>> Enable VM functions no >>>> VMCS shadowing no >>>> EPT-violation #VE no >>>> >>>>What shall I do if I wish to enable PLE? I have also tried this: >>>> >>> From above info, your physical cpu dose not support ple feature, >>> if you want to enable ple, your cpu must support ple feature, and 'PAUSE >>> exiting' must be 0-settting, 'PAUSE-loop exiting' must be 1-setting. >>> And, kvm-intel module will enable ple as default if your cpu support ple >>> feature. >>> >>Hi, Haoyu, >> >>I have another machine, in which Pause Loop Exiting is showing yes, >>but PAUSE Exiting is also showing yes, see below, but you said PAUSE >>exiting must be 0 setting, so what shall I do? Is PLE enabled or not? >> >check /sys/module/kvm_intel/parameters/ple_gap, if non-zero(>0), ple is >enabled, zero means ple is disabled. > Sorry, even /sys/module/kvm_intel/parameters/ple_gap is non-zero, it cannot say ple is enabled, it only means 'PAUSE-loop exiting' is 1-setting, but the 'PAUSE-loop exiting' is ignored if 'PAUSE exiting' is 1-settting. But Below words is from the intel 64 and IA-32 Architectures Software Developer’s Manual Volume 3C, • PAUSE.The behavior of each of this instruction depends on CPL and the settings of the “PAUSE exiting” and “PAUSE-loop exiting” VM-execution controls: — CPL= 0. • If the “PAUSE exiting” and “PAUSE-loop exiting” VM-execution controls are both 0, the PAUSE instruction executes normally. • If the “PAUSE exiting” VM-execution control is 1, the PAUSE instruction causes a VM exit (the “PAUSEloop exiting” VM-execution control is ignored if CPL = 0 and the “PAUSE exiting” VM-execution control is 1). • If the “PAUSE exiting” VM-execution control is 0 and the “PAUSE-loop exiting” VM-execution control is 1, the following treatment applies. The processor determines the amount of time between this execution of PAUSE and the previous execution of PAUSE at CPL 0. If this amount of time exceeds the value of the VM-execution control field PLE_Gap, the processor considers this execution to be the first execution of PAUSE in a loop. (It also does so for the first execution of PAUSE at CPL 0 after VM entry.) Otherwise, the processor determines the amount of time since the most recent execution of PAUSE that was considered to be the first in a loop. If this amount of time exceeds the value of the VM-execution control field PLE_Window, a VM exit occurs. For purposes of these computations, time is measured based on a counter that runs at the same rate as the timestamp counter (TSC). — CPL> 0. • If the “PAUSE exiting” VM-execution control is 0, the PAUSE instruction executes normally. • If the “PAUSE exiting” VM-execution control is 1, the PAUSE instruction causes a VM exit. The “PAUSE-loop exiting” VM-execution control is ignored if CPL > 0.
>Thanks, >Zhang Haoyu >>primary processor-based controls >> Interrupt window exiting yes >> Use TSC offsetting yes >> HLT exiting yes >> INVLPG exiting yes >> MWAIT exiting yes >> RDPMC exiting yes >> RDTSC exiting yes >> CR3-load exiting default >> CR3-store exiting default >> CR8-load exiting yes >> CR8-store exiting yes >> Use TPR shadow yes >> NMI-window exiting yes >> MOV-DR exiting yes >> Unconditional I/O exiting yes >> Use I/O bitmaps yes >> Monitor trap flag yes >> Use MSR bitmaps yes >> MONITOR exiting yes >> PAUSE exiting yes >> Activate secondary control yes >>secondary processor-based controls >> Virtualize APIC accesses yes >> Enable EPT yes >> Descriptor-table exiting yes >> Enable RDTSCP yes >> Virtualize x2APIC mode yes >> Enable VPID yes >> WBINVD exiting yes >> Unrestricted guest yes >> APIC register emulation no >> Virtual interrupt delivery no >> PAUSE-loop exiting yes >> RDRAND exiting no >> Enable INVPCID no >> Enable VM functions no >> VMCS shadowing no >> EPT-violation #VE no
