rcu-tasks: Use unique names for RCU-Tasks kthreads and messages

This commit causes the flavors of RCU Tasks to use different names
for their kthreads and in their console messages.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h
index 7f9ed20c26c755acecc941f7423a793a5ec1f990..9ca83c68e4864b1b3541dc095230ed9b4bcddc2d 100644 (file)
--- a/kernel/rcu/tasks.h
+++ b/kernel/rcu/tasks.h
@@ -22,6 +22,8 @@ typedef void (*rcu_tasks_gp_func_t)(struct rcu_tasks *rtp);
  * @kthread_ptr: This flavor's grace-period/callback-invocation kthread.
  * @gp_func: This flavor's grace-period-wait function.
  * @call_func: This flavor's call_rcu()-equivalent function.
+ * @name: This flavor's textual name.
+ * @kname: This flavor's kthread name.
  */
 struct rcu_tasks {
        struct rcu_head *cbs_head;
@@ -31,16 +33,20 @@ struct rcu_tasks {
        struct task_struct *kthread_ptr;
        rcu_tasks_gp_func_t gp_func;
        call_rcu_func_t call_func;
+       char *name;
+       char *kname;
 };
 
-#define DEFINE_RCU_TASKS(name, gp, call)                               \
-static struct rcu_tasks name =                                         \
+#define DEFINE_RCU_TASKS(rt_name, gp, call, n)                         \
+static struct rcu_tasks rt_name =                                      \
 {                                                                      \
-       .cbs_tail = &name.cbs_head,                                     \
-       .cbs_wq = __WAIT_QUEUE_HEAD_INITIALIZER(name.cbs_wq),           \
-       .cbs_lock = __RAW_SPIN_LOCK_UNLOCKED(name.cbs_lock),            \
+       .cbs_tail = &rt_name.cbs_head,                                  \
+       .cbs_wq = __WAIT_QUEUE_HEAD_INITIALIZER(rt_name.cbs_wq),        \
+       .cbs_lock = __RAW_SPIN_LOCK_UNLOCKED(rt_name.cbs_lock),         \
        .gp_func = gp,                                                  \
        .call_func = call,                                              \
+       .name = n,                                                      \
+       .kname = #rt_name,                                              \
 }
 
 /* Track exiting tasks in order to allow them to be waited for. */
@@ -145,8 +151,8 @@ static void __init rcu_spawn_tasks_kthread_generic(struct rcu_tasks *rtp)
 {
        struct task_struct *t;
 
-       t = kthread_run(rcu_tasks_kthread, rtp, "rcu_tasks_kthread");
-       if (WARN_ONCE(IS_ERR(t), "%s: Could not start Tasks-RCU grace-period kthread, OOM is now expected behavior\n", __func__))
+       t = kthread_run(rcu_tasks_kthread, rtp, "%s_kthread", rtp->kname);
+       if (WARN_ONCE(IS_ERR(t), "%s: Could not start %s grace-period kthread, OOM is now expected behavior\n", __func__, rtp->name))
                return;
        smp_mb(); /* Ensure others see full kthread. */
 }
@@ -342,7 +348,7 @@ static void rcu_tasks_wait_gp(struct rcu_tasks *rtp)
 }
 
 void call_rcu_tasks(struct rcu_head *rhp, rcu_callback_t func);
-DEFINE_RCU_TASKS(rcu_tasks, rcu_tasks_wait_gp, call_rcu_tasks);
+DEFINE_RCU_TASKS(rcu_tasks, rcu_tasks_wait_gp, call_rcu_tasks, "RCU Tasks");
 
 /**
  * call_rcu_tasks() - Queue an RCU for invocation task-based grace period
@@ -437,7 +443,8 @@ static void rcu_tasks_rude_wait_gp(struct rcu_tasks *rtp)
 }
 
 void call_rcu_tasks_rude(struct rcu_head *rhp, rcu_callback_t func);
-DEFINE_RCU_TASKS(rcu_tasks_rude, rcu_tasks_rude_wait_gp, call_rcu_tasks_rude);
+DEFINE_RCU_TASKS(rcu_tasks_rude, rcu_tasks_rude_wait_gp, call_rcu_tasks_rude,
+                "RCU Tasks Rude");
 
 /**
  * call_rcu_tasks_rude() - Queue a callback rude task-based grace period