73e75b416f
Existing KVM statistics are either just counters (kvm_stat) reported for KVM generally or trace based aproaches like kvm_trace. For KVM on powerpc we had the need to track the timings of the different exit types. While this could be achieved parsing data created with a kvm_trace extension this adds too much overhead (at least on embedded PowerPC) slowing down the workloads we wanted to measure. Therefore this patch adds a in-kernel exit timing statistic to the powerpc kvm code. These statistic is available per vm&vcpu under the kvm debugfs directory. As this statistic is low, but still some overhead it can be enabled via a .config entry and should be off by default. Since this patch touched all powerpc kvm_stat code anyway this code is now merged and simplified together with the exit timing statistic code (still working with exit timing disabled in .config). Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
59 lines
1.4 KiB
Text
59 lines
1.4 KiB
Text
#
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# KVM configuration
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#
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menuconfig VIRTUALIZATION
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bool "Virtualization"
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---help---
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Say Y here to get to see options for using your Linux host to run
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other operating systems inside virtual machines (guests).
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This option alone does not add any kernel code.
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If you say N, all options in this submenu will be skipped and
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disabled.
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if VIRTUALIZATION
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config KVM
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bool
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select PREEMPT_NOTIFIERS
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select ANON_INODES
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config KVM_440
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bool "KVM support for PowerPC 440 processors"
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depends on EXPERIMENTAL && 44x
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select KVM
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---help---
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Support running unmodified 440 guest kernels in virtual machines on
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440 host processors.
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This module provides access to the hardware capabilities through
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a character device node named /dev/kvm.
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If unsure, say N.
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config KVM_EXIT_TIMING
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bool "Detailed exit timing"
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depends on KVM
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---help---
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Calculate elapsed time for every exit/enter cycle. A per-vcpu
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report is available in debugfs kvm/vm#_vcpu#_timing.
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The overhead is relatively small, however it is not recommended for
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production environments.
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If unsure, say N.
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config KVM_TRACE
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bool "KVM trace support"
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depends on KVM && MARKERS && SYSFS
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select RELAY
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select DEBUG_FS
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default n
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---help---
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This option allows reading a trace of kvm-related events through
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relayfs. Note the ABI is not considered stable and will be
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modified in future updates.
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source drivers/virtio/Kconfig
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endif # VIRTUALIZATION
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