[Qemu-devel] [PATCH 1/3] qom: use cpu->in_cpu_list instead of QTAILQ_IN_USE

[Emilio G. Cota]

This paves the way for implementing the CPU list with an RCU QLIST.

Signed-off-by: Emilio G. Cota <c...@braap.org>
---
 cpus-common.c     | 3 ++-
 include/qom/cpu.h | 2 ++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/cpus-common.c b/cpus-common.c
index 59f751ecf9..6eaedae60b 100644
--- a/cpus-common.c
+++ b/cpus-common.c
@@ -85,6 +85,7 @@ void cpu_list_add(CPUState *cpu)
         assert(!cpu_index_auto_assigned);
     }
     QTAILQ_INSERT_TAIL(&cpus, cpu, node);
+    cpu->in_cpu_list = true;
     qemu_mutex_unlock(&qemu_cpu_list_lock);
 
     finish_safe_work(cpu);
@@ -93,7 +94,7 @@ void cpu_list_add(CPUState *cpu)
 void cpu_list_remove(CPUState *cpu)
 {
     qemu_mutex_lock(&qemu_cpu_list_lock);
-    if (!QTAILQ_IN_USE(cpu, node)) {
+    if (!cpu->in_cpu_list) {
         /* there is nothing to undo since cpu_exec_init() hasn't been called */
         qemu_mutex_unlock(&qemu_cpu_list_lock);
         return;
diff --git a/include/qom/cpu.h b/include/qom/cpu.h
index bd796579ee..aa555e27a7 100644
--- a/include/qom/cpu.h
+++ b/include/qom/cpu.h
@@ -411,6 +411,8 @@ struct CPUState {
 
     bool ignore_memory_transaction_failures;
 
+    bool in_cpu_list; /* protected by qemu_cpu_list_lock */
+
     /* Note that this is accessed at the start of every TB via a negative
        offset from AREG0.  Leave this field at the end so as to make the
        (absolute value) offset as small as possible.  This reduces code
-- 
2.17.1