[Qemu-devel] [mttcg RFC v4 1/6] cpus: async_run_on_cpu: kick only if needed

[Alvise Rigo <a.rigo@virtualopensystems.com>]

In some unique situations a vCPU can be kicked even if it's not ready to
execute TCG code i.e. when current_tb has never been set before.
This can happen with the atomic stress test (not kvm-unit-test based),
where a vCPU can query some work to a not yet started vCPU.

Signed-off-by: Alvise Rigo <a.rigo@virtualopensystems.com>
---
 cpus.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/cpus.c b/cpus.c
index f61530c..3d90142 100644
--- a/cpus.c
+++ b/cpus.c
@@ -935,7 +935,9 @@ void async_run_on_cpu(CPUState *cpu, void (*func)(void *data), void *data)
     wi->done = false;
     qemu_mutex_unlock(&cpu->work_mutex);
 
-    qemu_cpu_kick(cpu);
+    if (tcg_enabled() && (atomic_read(&cpu->tcg_exec_flag) == 1)) {
+        qemu_cpu_kick(cpu);
+    }
 }
 
 void async_run_safe_work_on_cpu(CPUState *cpu, void (*func)(void *data),
-- 
2.5.0