Commit 274529ba authored by Paul E. McKenney's avatar Paul E. McKenney
Browse files

rcu: Consolidate dumping of ftrace buffer 



This commit consolidates a couple definitions and several calls for
single-shot ftrace-buffer dumping.

Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
parent f55532a0

include/linux/rcupdate.h

+13 −0
Original line number Diff line number Diff line
@@ -1144,4 +1144,17 @@ static inline void rcu_sysidle_force_exit(void) 
#endif /* #else #ifdef CONFIG_NO_HZ_FULL_SYSIDLE */





/*

 * Dump the ftrace buffer, but only one time per callsite per boot.

 */

#define rcu_ftrace_dump(oops_dump_mode) \

do { \

	static atomic_t ___rfd_beenhere = ATOMIC_INIT(0); \

	\

	if (!atomic_read(&___rfd_beenhere) && \

	    !atomic_xchg(&___rfd_beenhere, 1)) \

		ftrace_dump(oops_dump_mode); \

} while (0)





#endif /* __LINUX_RCUPDATE_H */

kernel/rcu/rcutorture.c

+3 −14
Original line number Diff line number Diff line
@@ -1082,17 +1082,6 @@ rcu_torture_fakewriter(void *arg) 
	return 0;

}



static void rcutorture_trace_dump(void)

{

	static atomic_t beenhere = ATOMIC_INIT(0);



	if (atomic_read(&beenhere))

		return;

	if (atomic_xchg(&beenhere, 1) != 0)

		return;

	ftrace_dump(DUMP_ALL);

}



/*

 * RCU torture reader from timer handler.  Dereferences rcu_torture_current,

 * incrementing the corresponding element of the pipeline array.  The
@@ -1142,7 +1131,7 @@ static void rcu_torture_timer(unsigned long unused) 
	if (pipe_count > 1) {

		do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu, ts,

					  started, completed);

		rcutorture_trace_dump();

		rcu_ftrace_dump(DUMP_ALL);

	}

	__this_cpu_inc(rcu_torture_count[pipe_count]);

	completed = completed - started;
@@ -1215,7 +1204,7 @@ rcu_torture_reader(void *arg) 
		if (pipe_count > 1) {

			do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu,

						  ts, started, completed);

			rcutorture_trace_dump();

			rcu_ftrace_dump(DUMP_ALL);

		}

		__this_cpu_inc(rcu_torture_count[pipe_count]);

		completed = completed - started;
@@ -1333,7 +1322,7 @@ rcu_torture_stats_print(void) 
			 rcu_torture_writer_state,

			 gpnum, completed, flags);

		show_rcu_gp_kthreads();

		rcutorture_trace_dump();

		rcu_ftrace_dump(DUMP_ALL);

	}

	rtcv_snap = rcu_torture_current_version;

}

kernel/rcu/tree.c

+2 −2
Original line number Diff line number Diff line
@@ -637,7 +637,7 @@ static void rcu_eqs_enter_common(long long oldval, bool user) 
			idle_task(smp_processor_id());



		trace_rcu_dyntick(TPS("Error on entry: not idle task"), oldval, 0);

		ftrace_dump(DUMP_ORIG);

		rcu_ftrace_dump(DUMP_ORIG);

		WARN_ONCE(1, "Current pid: %d comm: %s / Idle pid: %d comm: %s",

			  current->pid, current->comm,

			  idle->pid, idle->comm); /* must be idle task! */
@@ -799,7 +799,7 @@ static void rcu_eqs_exit_common(long long oldval, int user) 


		trace_rcu_dyntick(TPS("Error on exit: not idle task"),

				  oldval, rdtp->dynticks_nesting);

		ftrace_dump(DUMP_ORIG);

		rcu_ftrace_dump(DUMP_ORIG);

		WARN_ONCE(1, "Current pid: %d comm: %s / Idle pid: %d comm: %s",

			  current->pid, current->comm,

			  idle->pid, idle->comm); /* must be idle task! */