commit cc84de9570ffe01a9c3c169bd62ab9586a9a080c
author Marcelo Tosatti <mtosatti@redhat.com> Wed Feb 17 20:14:42 2010 -0200
committer Avi Kivity <avi@redhat.com> Mon Feb 22 10:58:33 2010 +0200
tree ea13b44d105ea50dd1f85ccade0f851481a905e6
parent fed6c3444c714e88eb84dae58fcde0182865db8f

kvm: consume internal signal with sigtimedwait

Change the way the internal qemu signal, used for communication between
iothread and vcpus, is handled.

Block and consume it with sigtimedwait on the outer vcpu loop, which
allows more precise timing control.

Change from standard signal (SIGUSR1) to real-time one, so multiple
signals are not collapsed.

Set the signal number on KVM's in-kernel allowed sigmask.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

kvm-all.c

diff --git a/kvm-all.c b/kvm-all.c
index 79345b2..38c372f 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -771,6 +771,7 @@
         kvm_arch_post_run(env, run);
 
         if (ret == -EINTR || ret == -EAGAIN) {
+            cpu_exit(env);
             dprintf("io window exit\n");
             ret = 0;
             break;
@@ -1116,3 +1117,21 @@
 {
 }
 #endif /* !KVM_CAP_SET_GUEST_DEBUG */
+
+int kvm_set_signal_mask(CPUState *env, const sigset_t *sigset)
+{
+    struct kvm_signal_mask *sigmask;
+    int r;
+
+    if (!sigset)
+        return kvm_vcpu_ioctl(env, KVM_SET_SIGNAL_MASK, NULL);
+
+    sigmask = qemu_malloc(sizeof(*sigmask) + sizeof(*sigset));
+
+    sigmask->len = 8;
+    memcpy(sigmask->sigset, sigset, sizeof(*sigset));
+    r = kvm_vcpu_ioctl(env, KVM_SET_SIGNAL_MASK, sigmask);
+    free(sigmask);
+
+    return r;
+}