tracing: Use CONFIG_PREEMPTION

CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by
CONFIG_PREEMPT_RT. Both PREEMPT and PREEMPT_RT require the same
functionality which today depends on CONFIG_PREEMPT.

Switch the conditionals in the tracer over to CONFIG_PREEMPTION.

This is the first step to make the tracer work on RT. The other small
tweaks are submitted separately.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20190726212124.409766323@linutronix.deSigned-off-by: Ingo Molnar <mingo@kernel.org>

kernel/trace/Kconfig

@@ -179,7 +179,7 @@ config TRACE_PREEMPT_TOGGLE
 config PREEMPTIRQ_EVENTS
 	bool "Enable trace events for preempt and irq disable/enable"
 	select TRACE_IRQFLAGS
-	select TRACE_PREEMPT_TOGGLE if PREEMPT
+	select TRACE_PREEMPT_TOGGLE if PREEMPTION
 	select GENERIC_TRACER
 	default n
 	help
@@ -214,7 +214,7 @@ config PREEMPT_TRACER
 	bool "Preemption-off Latency Tracer"
 	default n
 	depends on !ARCH_USES_GETTIMEOFFSET
-	depends on PREEMPT
+	depends on PREEMPTION
 	select GENERIC_TRACER
 	select TRACER_MAX_TRACE
 	select RING_BUFFER_ALLOW_SWAP

kernel/trace/ftrace.c

@@ -2814,7 +2814,7 @@ int ftrace_shutdown(struct ftrace_ops *ops, int command)
 		 * synchornize_rcu_tasks() will wait for those tasks to
 		 * execute and either schedule voluntarily or enter user space.
 		 */
-		if (IS_ENABLED(CONFIG_PREEMPT))
+		if (IS_ENABLED(CONFIG_PREEMPTION))
 			synchronize_rcu_tasks();
 
  free_ops:

kernel/trace/ring_buffer_benchmark.c

@@ -267,7 +267,7 @@ static void ring_buffer_producer(void)
 		if (consumer && !(cnt % wakeup_interval))
 			wake_up_process(consumer);
 
-#ifndef CONFIG_PREEMPT
+#ifndef CONFIG_PREEMPTION
 		/*
 		 * If we are a non preempt kernel, the 10 second run will
 		 * stop everything while it runs. Instead, we will call

kernel/trace/trace_events.c

@@ -255,12 +255,12 @@ void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer,
 	local_save_flags(fbuffer->flags);
 	fbuffer->pc = preempt_count();
 	/*
-	 * If CONFIG_PREEMPT is enabled, then the tracepoint itself disables
+	 * If CONFIG_PREEMPTION is enabled, then the tracepoint itself disables
 	 * preemption (adding one to the preempt_count). Since we are
 	 * interested in the preempt_count at the time the tracepoint was
 	 * hit, we need to subtract one to offset the increment.
 	 */
-	if (IS_ENABLED(CONFIG_PREEMPT))
+	if (IS_ENABLED(CONFIG_PREEMPTION))
 		fbuffer->pc--;
 	fbuffer->trace_file = trace_file;