rcutorture: Make grace-period kthread report match RCU flavor being tested

At the end of the test and after rcu_torture_writer() stalls, rcutorture
invokes show_rcu_gp_kthreads() in order to dump out information on the
RCU grace-period kthread.  This makes a lot of sense when testing vanilla
RCU, but not so much for the other flavors.  This commit therefore allows
per-flavor kthread-dump functions to be specified.

[ paulmck: Apply feedback from kernel test robot <lkp@intel.com>. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h
index e01cba5e4b5290c5f59790cad95b1dbab4c3a060..59ef1ae6dc37c188105049606f2e3302c22fb895 100644 (file)
--- a/kernel/rcu/rcu.h
+++ b/kernel/rcu/rcu.h
@@ -533,4 +533,20 @@ static inline bool rcu_is_nocb_cpu(int cpu) { return false; }
 static inline void rcu_bind_current_to_nocb(void) { }
 #endif
 
+#if !defined(CONFIG_TINY_RCU) && defined(CONFIG_TASKS_RCU)
+void show_rcu_tasks_classic_gp_kthread(void);
+#else
+static inline void show_rcu_tasks_classic_gp_kthread(void) {}
+#endif
+#if !defined(CONFIG_TINY_RCU) && defined(CONFIG_TASKS_RUDE_RCU)
+void show_rcu_tasks_rude_gp_kthread(void);
+#else
+static inline void show_rcu_tasks_rude_gp_kthread(void) {}
+#endif
+#if !defined(CONFIG_TINY_RCU) && defined(CONFIG_TASKS_TRACE_RCU)
+void show_rcu_tasks_trace_gp_kthread(void);
+#else
+static inline void show_rcu_tasks_trace_gp_kthread(void) {}
+#endif
+
 #endif /* __LINUX_RCU_H */

diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 916ea4f66e4b2380c3cc7d3bd1c10bb0601cd3c9..c811f23692bf2a24dc79938b285df302f7283f41 100644 (file)
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -317,6 +317,7 @@ struct rcu_torture_ops {
        void (*cb_barrier)(void);
        void (*fqs)(void);
        void (*stats)(void);
+       void (*gp_kthread_dbg)(void);
        int (*stall_dur)(void);
        int irq_capable;
        int can_boost;
@@ -466,6 +467,7 @@ static struct rcu_torture_ops rcu_ops = {
        .cb_barrier     = rcu_barrier,
        .fqs            = rcu_force_quiescent_state,
        .stats          = NULL,
+       .gp_kthread_dbg = show_rcu_gp_kthreads,
        .stall_dur      = rcu_jiffies_till_stall_check,
        .irq_capable    = 1,
        .can_boost      = rcu_can_boost(),
@@ -693,6 +695,7 @@ static struct rcu_torture_ops tasks_ops = {
        .exp_sync       = synchronize_rcu_mult_test,
        .call           = call_rcu_tasks,
        .cb_barrier     = rcu_barrier_tasks,
+       .gp_kthread_dbg = show_rcu_tasks_classic_gp_kthread,
        .fqs            = NULL,
        .stats          = NULL,
        .irq_capable    = 1,
@@ -762,6 +765,7 @@ static struct rcu_torture_ops tasks_rude_ops = {
        .exp_sync       = synchronize_rcu_tasks_rude,
        .call           = call_rcu_tasks_rude,
        .cb_barrier     = rcu_barrier_tasks_rude,
+       .gp_kthread_dbg = show_rcu_tasks_rude_gp_kthread,
        .fqs            = NULL,
        .stats          = NULL,
        .irq_capable    = 1,
@@ -800,6 +804,7 @@ static struct rcu_torture_ops tasks_tracing_ops = {
        .exp_sync       = synchronize_rcu_tasks_trace,
        .call           = call_rcu_tasks_trace,
        .cb_barrier     = rcu_barrier_tasks_trace,
+       .gp_kthread_dbg = show_rcu_tasks_trace_gp_kthread,
        .fqs            = NULL,
        .stats          = NULL,
        .irq_capable    = 1,
@@ -1594,7 +1599,8 @@ rcu_torture_stats_print(void)
                        sched_show_task(wtp);
                        splatted = true;
                }
-               show_rcu_gp_kthreads();
+               if (cur_ops->gp_kthread_dbg)
+                       cur_ops->gp_kthread_dbg();
                rcu_ftrace_dump(DUMP_ALL);
        }
        rtcv_snap = rcu_torture_current_version;
@@ -2472,7 +2478,8 @@ rcu_torture_cleanup(void)
                return;
        }
 
-       show_rcu_gp_kthreads();
+       if (cur_ops->gp_kthread_dbg)
+               cur_ops->gp_kthread_dbg();
        rcu_torture_read_exit_cleanup();
        rcu_torture_barrier_cleanup();
        rcu_torture_fwd_prog_cleanup();

diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h
index a93271fc2572051179f6616e963dd84088619876..0b459890fdcc2b6ea43f6afa650f6bc034a55d5b 100644 (file)
--- a/kernel/rcu/tasks.h
+++ b/kernel/rcu/tasks.h
@@ -290,7 +290,7 @@ static void show_rcu_tasks_generic_gp_kthread(struct rcu_tasks *rtp, char *s)
                ".C"[!!data_race(rtp->cbs_head)],
                s);
 }
-#endif /* #ifndef CONFIG_TINY_RCU */
+#endif // #ifndef CONFIG_TINY_RCU
 
 static void exit_tasks_rcu_finish_trace(struct task_struct *t);
 
@@ -568,12 +568,13 @@ static int __init rcu_spawn_tasks_kthread(void)
 }
 core_initcall(rcu_spawn_tasks_kthread);
 
-#ifndef CONFIG_TINY_RCU
-static void show_rcu_tasks_classic_gp_kthread(void)
+#if !defined(CONFIG_TINY_RCU)
+void show_rcu_tasks_classic_gp_kthread(void)
 {
        show_rcu_tasks_generic_gp_kthread(&rcu_tasks, "");
 }
-#endif /* #ifndef CONFIG_TINY_RCU */
+EXPORT_SYMBOL_GPL(show_rcu_tasks_classic_gp_kthread);
+#endif // !defined(CONFIG_TINY_RCU)
 
 /* Do the srcu_read_lock() for the above synchronize_srcu().  */
 void exit_tasks_rcu_start(void) __acquires(&tasks_rcu_exit_srcu)
@@ -595,7 +596,6 @@ void exit_tasks_rcu_finish(void) __releases(&tasks_rcu_exit_srcu)
 }
 
 #else /* #ifdef CONFIG_TASKS_RCU */
-static inline void show_rcu_tasks_classic_gp_kthread(void) { }
 void exit_tasks_rcu_start(void) { }
 void exit_tasks_rcu_finish(void) { exit_tasks_rcu_finish_trace(current); }
 #endif /* #else #ifdef CONFIG_TASKS_RCU */
@@ -696,16 +696,14 @@ static int __init rcu_spawn_tasks_rude_kthread(void)
 }
 core_initcall(rcu_spawn_tasks_rude_kthread);
 
-#ifndef CONFIG_TINY_RCU
-static void show_rcu_tasks_rude_gp_kthread(void)
+#if !defined(CONFIG_TINY_RCU)
+void show_rcu_tasks_rude_gp_kthread(void)
 {
        show_rcu_tasks_generic_gp_kthread(&rcu_tasks_rude, "");
 }
-#endif /* #ifndef CONFIG_TINY_RCU */
-
-#else /* #ifdef CONFIG_TASKS_RUDE_RCU */
-static void show_rcu_tasks_rude_gp_kthread(void) {}
-#endif /* #else #ifdef CONFIG_TASKS_RUDE_RCU */
+EXPORT_SYMBOL_GPL(show_rcu_tasks_rude_gp_kthread);
+#endif // !defined(CONFIG_TINY_RCU)
+#endif /* #ifdef CONFIG_TASKS_RUDE_RCU */
 
 ////////////////////////////////////////////////////////////////////////
 //
@@ -1199,8 +1197,8 @@ static int __init rcu_spawn_tasks_trace_kthread(void)
 }
 core_initcall(rcu_spawn_tasks_trace_kthread);
 
-#ifndef CONFIG_TINY_RCU
-static void show_rcu_tasks_trace_gp_kthread(void)
+#if !defined(CONFIG_TINY_RCU)
+void show_rcu_tasks_trace_gp_kthread(void)
 {
        char buf[64];
 
@@ -1210,11 +1208,11 @@ static void show_rcu_tasks_trace_gp_kthread(void)
                data_race(n_heavy_reader_attempts));
        show_rcu_tasks_generic_gp_kthread(&rcu_tasks_trace, buf);
 }
-#endif /* #ifndef CONFIG_TINY_RCU */
+EXPORT_SYMBOL_GPL(show_rcu_tasks_trace_gp_kthread);
+#endif // !defined(CONFIG_TINY_RCU)
 
 #else /* #ifdef CONFIG_TASKS_TRACE_RCU */
 static void exit_tasks_rcu_finish_trace(struct task_struct *t) { }
-static inline void show_rcu_tasks_trace_gp_kthread(void) {}
 #endif /* #else #ifdef CONFIG_TASKS_TRACE_RCU */
 
 #ifndef CONFIG_TINY_RCU