On 25/08/14 10:24, Christian Borntraeger wrote: > On 19/08/14 16:45, Christian Borntraeger wrote: >> We dont have to wait for a grace period if there is no oldpid that >> we are going to free. putpid also checks for NULL, so this patch >> only fences synchronize_rcu. >> >> Signed-off-by: Christian Borntraeger <borntrae...@de.ibm.com> >> --- >> virt/kvm/kvm_main.c | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c >> index 33712fb..39b1603 100644 >> --- a/virt/kvm/kvm_main.c >> +++ b/virt/kvm/kvm_main.c >> @@ -129,7 +129,8 @@ int vcpu_load(struct kvm_vcpu *vcpu) >> struct pid *oldpid = vcpu->pid; >> struct pid *newpid = get_task_pid(current, PIDTYPE_PID); >> rcu_assign_pointer(vcpu->pid, newpid); >> - synchronize_rcu(); >> + if (oldpid) >> + synchronize_rcu(); >> put_pid(oldpid); >> } >> cpu = get_cpu(); >> > > Ping. > That variant should be enough for us for future QEMUs. David has prepared > some patches in QEMU that makes the other problems go away (mostly) which are > currently under internal review/test. > Let me know if you want to have the put_pid inside the if as well (or feel > free to fix up yourself code and patch description). > > Thanks
Just updated kvm/next. Sorry for the noise. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
