>>>>>>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. So PLE is still not enabled on my machine? Then how to let >"PAUSE Exiting" to be 0-setting? > Sorry, I don't know, but you can make a confirmation first. "PAUSE Exiting" is 0-setting in setup_vmcs_config() function, but it maybe 1-setting in adjust_vmx_controls(), so you can printk the bitwise-and result of (_cpu_based_exec_control & CPU_BASED_PAUSE_EXITING) after adjust_vmx_controls in setup_vmcs_config. Any better ideas? Thanks, Zhang Haoyu >-Jidong > >>>>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 ��.n��������+%������w��{.n�����o�^n�r������&��z�ޗ�zf���h���~����������_��+v���)ߣ�
