summaryrefslogtreecommitdiff
path: root/arch/x86
diff options
context:
space:
mode:
authorNir Weiner <nir.weiner@oracle.com>2019-01-27 12:17:16 +0200
committerPaolo Bonzini <pbonzini@redhat.com>2019-02-20 22:48:51 +0100
commitdee339b5c1da3e6fa139b97f74f99dc9f0b03ff6 (patch)
tree6693b07487412d7ca10a17cf07d31dcdb9d43fe0 /arch/x86
parent49113d360bdeb4dd916fb6bffbcc3e157422b6fd (diff)
KVM: Never start grow vCPU halt_poll_ns from value below halt_poll_ns_grow_start
grow_halt_poll_ns() have a strange behaviour in case (vcpu->halt_poll_ns != 0) && (vcpu->halt_poll_ns < halt_poll_ns_grow_start). In this case, vcpu->halt_poll_ns will be multiplied by grow factor (halt_poll_ns_grow) which will require several grow iteration in order to reach a value bigger than halt_poll_ns_grow_start. This means that growing vcpu->halt_poll_ns from value of 0 is slower than growing it from a positive value less than halt_poll_ns_grow_start. Which is misleading and inaccurate. Fix issue by changing grow_halt_poll_ns() to set vcpu->halt_poll_ns to halt_poll_ns_grow_start in any case that (vcpu->halt_poll_ns < halt_poll_ns_grow_start). Regardless if vcpu->halt_poll_ns is 0. use READ_ONCE to get a consistent number for all cases. Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Liran Alon <liran.alon@oracle.com> Signed-off-by: Nir Weiner <nir.weiner@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86')
0 files changed, 0 insertions, 0 deletions