diff options
Diffstat (limited to 'Documentation/virtual/kvm')
-rw-r--r-- | Documentation/virtual/kvm/api.txt | 11 | ||||
-rw-r--r-- | Documentation/virtual/kvm/locking.txt | 12 | ||||
-rw-r--r-- | Documentation/virtual/kvm/msr.txt | 9 | ||||
-rw-r--r-- | Documentation/virtual/kvm/review-checklist.txt | 4 |
4 files changed, 32 insertions, 4 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 739db9ab16b2..6bbceb9a3a19 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -777,6 +777,17 @@ Gets the current timestamp of kvmclock as seen by the current guest. In conjunction with KVM_SET_CLOCK, it is used to ensure monotonicity on scenarios such as migration. +When KVM_CAP_ADJUST_CLOCK is passed to KVM_CHECK_EXTENSION, it returns the +set of bits that KVM can return in struct kvm_clock_data's flag member. + +The only flag defined now is KVM_CLOCK_TSC_STABLE. If set, the returned +value is the exact kvmclock value seen by all VCPUs at the instant +when KVM_GET_CLOCK was called. If clear, the returned value is simply +CLOCK_MONOTONIC plus a constant offset; the offset can be modified +with KVM_SET_CLOCK. KVM will try to make all VCPUs follow this clock, +but the exact value read by each VCPU could differ, because the host +TSC is not stable. + struct kvm_clock_data { __u64 clock; /* kvmclock current value */ __u32 flags; diff --git a/Documentation/virtual/kvm/locking.txt b/Documentation/virtual/kvm/locking.txt index f2491a8c68b4..e5dd9f4d6100 100644 --- a/Documentation/virtual/kvm/locking.txt +++ b/Documentation/virtual/kvm/locking.txt @@ -4,7 +4,17 @@ KVM Lock Overview 1. Acquisition Orders --------------------- -(to be written) +The acquisition orders for mutexes are as follows: + +- kvm->lock is taken outside vcpu->mutex + +- kvm->lock is taken outside kvm->slots_lock and kvm->irq_lock + +- kvm->slots_lock is taken outside kvm->irq_lock, though acquiring + them together is quite rare. + +For spinlocks, kvm_lock is taken outside kvm->mmu_lock. Everything +else is a leaf: no other lock is taken inside the critical sections. 2: Exception ------------ diff --git a/Documentation/virtual/kvm/msr.txt b/Documentation/virtual/kvm/msr.txt index 2a71c8f29f68..0a9ea515512a 100644 --- a/Documentation/virtual/kvm/msr.txt +++ b/Documentation/virtual/kvm/msr.txt @@ -208,7 +208,9 @@ MSR_KVM_STEAL_TIME: 0x4b564d03 __u64 steal; __u32 version; __u32 flags; - __u32 pad[12]; + __u8 preempted; + __u8 u8_pad[3]; + __u32 pad[11]; } whose data will be filled in by the hypervisor periodically. Only one @@ -232,6 +234,11 @@ MSR_KVM_STEAL_TIME: 0x4b564d03 nanoseconds. Time during which the vcpu is idle, will not be reported as steal time. + preempted: indicate the vCPU who owns this struct is running or + not. Non-zero values mean the vCPU has been preempted. Zero + means the vCPU is not preempted. NOTE, it is always zero if the + the hypervisor doesn't support this field. + MSR_KVM_EOI_EN: 0x4b564d04 data: Bit 0 is 1 when PV end of interrupt is enabled on the vcpu; 0 when disabled. Bit 1 is reserved and must be zero. When PV end of diff --git a/Documentation/virtual/kvm/review-checklist.txt b/Documentation/virtual/kvm/review-checklist.txt index a850986ed684..a83b27635fdd 100644 --- a/Documentation/virtual/kvm/review-checklist.txt +++ b/Documentation/virtual/kvm/review-checklist.txt @@ -1,8 +1,8 @@ Review checklist for kvm patches ================================ -1. The patch must follow Documentation/CodingStyle and - Documentation/SubmittingPatches. +1. The patch must follow Documentation/process/coding-style.rst and + Documentation/process/submitting-patches.rst. 2. Patches should be against kvm.git master branch. |