Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-23 12:42:02 +00:00
Code Issues Packages Projects Releases Wiki Activity

KVM: handle last_boosted_vcpu = 0 case

Browse Source 
If last_boosted_vcpu == 0, then we fall through all test cases and
may end up with all VCPUs pouncing on vcpu 0.  With a large enough
guest, this can result in enormous runqueue lock contention, which
can prevent vcpu0 from running, leading to a livelock.

Changing < to <= makes sure we properly handle that case.

Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
This commit is contained in:
Rik van Riel 2012-06-19 16:51:04 -04:00 committed by Marcelo Tosatti
parent 21b26c0853
commit 5cfc2aabcb
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
virt/kvm/kvm_main.c
View File

@ -1598,7 +1598,7 @@ void kvm_vcpu_on_spin(struct kvm_vcpu *me)
*/
for (pass = 0; pass < 2 && !yielded; pass++) {
kvm_for_each_vcpu(i, vcpu, kvm) {
if (!pass && i < last_boosted_vcpu) {
if (!pass && i <= last_boosted_vcpu) {
i = last_boosted_vcpu;
continue;
} else if (pass && i > last_boosted_vcpu)