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| author | Wanpeng Li <wanpengli@tencent.com> | 2019-06-11 20:23:48 +0800 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2019-07-02 18:56:01 +0200 |
| commit | f85f6e7bc9682a6d8b342c010cd6aa58521fdeec (patch) | |
| tree | 5ca2f323769a35386e2a24b4c21d4c099778e950 /Documentation/virtual/kvm | |
| parent | 11e349143e3289ab99f1b4858649f60703b7bf35 (diff) | |
| download | linux-f85f6e7bc9682a6d8b342c010cd6aa58521fdeec.tar.bz2 | |
KVM: X86: Yield to IPI target if necessary
When sending a call-function IPI-many to vCPUs, yield if any of
the IPI target vCPUs was preempted, we just select the first
preempted target vCPU which we found since the state of target
vCPUs can change underneath and to avoid race conditions.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'Documentation/virtual/kvm')
| -rw-r--r-- | Documentation/virtual/kvm/hypercalls.txt | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/Documentation/virtual/kvm/hypercalls.txt b/Documentation/virtual/kvm/hypercalls.txt index da24c138c8d1..da210651f714 100644 --- a/Documentation/virtual/kvm/hypercalls.txt +++ b/Documentation/virtual/kvm/hypercalls.txt @@ -141,3 +141,14 @@ a0 corresponds to the APIC ID in the third argument (a2), bit 1 corresponds to the APIC ID a2+1, and so on. Returns the number of CPUs to which the IPIs were delivered successfully. + +7. KVM_HC_SCHED_YIELD +------------------------ +Architecture: x86 +Status: active +Purpose: Hypercall used to yield if the IPI target vCPU is preempted + +a0: destination APIC ID + +Usage example: When sending a call-function IPI-many to vCPUs, yield if +any of the IPI target vCPUs was preempted. |