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authorLinus Torvalds <torvalds@linux-foundation.org>2019-03-15 15:00:28 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-03-15 15:00:28 -0700
commit636deed6c0bc137a7c4f4a97ae1fcf0ad75323da (patch)
tree7bd27189b8e30e3c1466f7730831a08db65f8646 /Documentation/virtual/kvm/halt-polling.txt
parentaa2e3ac64ace127f403be85aa4d6015b859385f2 (diff)
parent4a605bc08e98381d8df61c30a4acb2eac15eb7da (diff)
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini: "ARM: - some cleanups - direct physical timer assignment - cache sanitization for 32-bit guests s390: - interrupt cleanup - introduction of the Guest Information Block - preparation for processor subfunctions in cpu models PPC: - bug fixes and improvements, especially related to machine checks and protection keys x86: - many, many cleanups, including removing a bunch of MMU code for unnecessary optimizations - AVIC fixes Generic: - memcg accounting" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (147 commits) kvm: vmx: fix formatting of a comment KVM: doc: Document the life cycle of a VM and its resources MAINTAINERS: Add KVM selftests to existing KVM entry Revert "KVM/MMU: Flush tlb directly in the kvm_zap_gfn_range()" KVM: PPC: Book3S: Add count cache flush parameters to kvmppc_get_cpu_char() KVM: PPC: Fix compilation when KVM is not enabled KVM: Minor cleanups for kvm_main.c KVM: s390: add debug logging for cpu model subfunctions KVM: s390: implement subfunction processor calls arm64: KVM: Fix architecturally invalid reset value for FPEXC32_EL2 KVM: arm/arm64: Remove unused timer variable KVM: PPC: Book3S: Improve KVM reference counting KVM: PPC: Book3S HV: Fix build failure without IOMMU support Revert "KVM: Eliminate extra function calls in kvm_get_dirty_log_protect()" x86: kvmguest: use TSC clocksource if invariant TSC is exposed KVM: Never start grow vCPU halt_poll_ns from value below halt_poll_ns_grow_start KVM: Expose the initial start value in grow_halt_poll_ns() as a module parameter KVM: grow_halt_poll_ns() should never shrink vCPU halt_poll_ns KVM: x86/mmu: Consolidate kvm_mmu_zap_all() and kvm_mmu_zap_mmio_sptes() KVM: x86/mmu: WARN if zapping a MMIO spte results in zapping children ...
Diffstat (limited to 'Documentation/virtual/kvm/halt-polling.txt')
-rw-r--r--Documentation/virtual/kvm/halt-polling.txt37
1 files changed, 23 insertions, 14 deletions
diff --git a/Documentation/virtual/kvm/halt-polling.txt b/Documentation/virtual/kvm/halt-polling.txt
index 4a8418318769..4f791b128dd2 100644
--- a/Documentation/virtual/kvm/halt-polling.txt
+++ b/Documentation/virtual/kvm/halt-polling.txt
@@ -53,7 +53,8 @@ the global max polling interval then the polling interval can be increased in
the hope that next time during the longer polling interval the wake up source
will be received while the host is polling and the latency benefits will be
received. The polling interval is grown in the function grow_halt_poll_ns() and
-is multiplied by the module parameter halt_poll_ns_grow.
+is multiplied by the module parameters halt_poll_ns_grow and
+halt_poll_ns_grow_start.
In the event that the total block time was greater than the global max polling
interval then the host will never poll for long enough (limited by the global
@@ -80,22 +81,30 @@ shrunk. These variables are defined in include/linux/kvm_host.h and as module
parameters in virt/kvm/kvm_main.c, or arch/powerpc/kvm/book3s_hv.c in the
powerpc kvm-hv case.
-Module Parameter | Description | Default Value
+Module Parameter | Description | Default Value
--------------------------------------------------------------------------------
-halt_poll_ns | The global max polling interval | KVM_HALT_POLL_NS_DEFAULT
- | which defines the ceiling value |
- | of the polling interval for | (per arch value)
- | each vcpu. |
+halt_poll_ns | The global max polling | KVM_HALT_POLL_NS_DEFAULT
+ | interval which defines |
+ | the ceiling value of the |
+ | polling interval for | (per arch value)
+ | each vcpu. |
--------------------------------------------------------------------------------
-halt_poll_ns_grow | The value by which the halt | 2
- | polling interval is multiplied |
- | in the grow_halt_poll_ns() |
- | function. |
+halt_poll_ns_grow | The value by which the | 2
+ | halt polling interval is |
+ | multiplied in the |
+ | grow_halt_poll_ns() |
+ | function. |
--------------------------------------------------------------------------------
-halt_poll_ns_shrink | The value by which the halt | 0
- | polling interval is divided in |
- | the shrink_halt_poll_ns() |
- | function. |
+halt_poll_ns_grow_start | The initial value to grow | 10000
+ | to from zero in the |
+ | grow_halt_poll_ns() |
+ | function. |
+--------------------------------------------------------------------------------
+halt_poll_ns_shrink | The value by which the | 0
+ | halt polling interval is |
+ | divided in the |
+ | shrink_halt_poll_ns() |
+ | function. |
--------------------------------------------------------------------------------
These module parameters can be set from the debugfs files in: