Commit 76f0d073 authored by Steven Rostedt's avatar Steven Rostedt Committed by Steven Rostedt
Browse files

tracing: remove users of tracing_reset 



The function tracing_reset is deprecated for outside use of trace.c.

The new function to reset the the buffers is tracing_reset_online_cpus.

The reason for this is that resetting the buffers while the event
trace points are active can corrupt the buffers, because they may
be writing at the time of reset. The tracing_reset_online_cpus disables
writes and waits for current writers to finish.

This patch replaces all users of tracing_reset except for the latency
tracers. Those changes require more work and will be removed in the
following patches.

Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
parent 621968cd

kernel/trace/kmemtrace.c

+1 −3
Original line number Original line Diff line number Diff line
@@ -183,11 +183,9 @@ static void kmemtrace_stop_probes(void) 




static int kmem_trace_init(struct trace_array *tr)

static int kmem_trace_init(struct trace_array *tr)

{

{

	int cpu;

	kmemtrace_array = tr;

	kmemtrace_array = tr;





	for_each_cpu(cpu, cpu_possible_mask)

	tracing_reset_online_cpus(tr);

		tracing_reset(tr, cpu);





	kmemtrace_start_probes();

	kmemtrace_start_probes();

kernel/trace/trace.c

+2 −5
Original line number Original line Diff line number Diff line
@@ -550,7 +550,6 @@ __acquires(kernel_lock) 
	if (type->selftest && !tracing_selftest_disabled) {

	if (type->selftest && !tracing_selftest_disabled) {

		struct tracer *saved_tracer = current_trace;

		struct tracer *saved_tracer = current_trace;

		struct trace_array *tr = &global_trace;

		struct trace_array *tr = &global_trace;

		int i;





		/*

		/*

		 * Run a selftest on this tracer.

		 * Run a selftest on this tracer.
@@ -559,8 +558,7 @@ __acquires(kernel_lock) 
		 * internal tracing to verify that everything is in order.

		 * internal tracing to verify that everything is in order.

		 * If we fail, we do not register this tracer.

		 * If we fail, we do not register this tracer.

		 */

		 */

		for_each_tracing_cpu(i)

		tracing_reset_online_cpus(tr);

			tracing_reset(tr, i);





		current_trace = type;

		current_trace = type;

		/* the test is responsible for initializing and enabling */

		/* the test is responsible for initializing and enabling */
@@ -573,8 +571,7 @@ __acquires(kernel_lock) 
			goto out;

			goto out;

		}

		}

		/* Only reset on passing, to avoid touching corrupted buffers */

		/* Only reset on passing, to avoid touching corrupted buffers */

		for_each_tracing_cpu(i)

		tracing_reset_online_cpus(tr);

			tracing_reset(tr, i);





		printk(KERN_CONT "PASSED\n");

		printk(KERN_CONT "PASSED\n");

	}

	}

kernel/trace/trace_boot.c

+1 −3
Original line number Original line Diff line number Diff line
@@ -41,14 +41,12 @@ void disable_boot_trace(void) 




static int boot_trace_init(struct trace_array *tr)

static int boot_trace_init(struct trace_array *tr)

{

{

	int cpu;

	boot_trace = tr;

	boot_trace = tr;





	if (!tr)

	if (!tr)

		return 0;

		return 0;





	for_each_cpu(cpu, cpu_possible_mask)

	tracing_reset_online_cpus(tr);

		tracing_reset(tr, cpu);





	tracing_sched_switch_assign_trace(tr);

	tracing_sched_switch_assign_trace(tr);

	return 0;

	return 0;

kernel/trace/trace_power.c

+1 −3
Original line number Original line Diff line number Diff line
@@ -144,14 +144,12 @@ static void power_trace_reset(struct trace_array *tr) 




static int power_trace_init(struct trace_array *tr)

static int power_trace_init(struct trace_array *tr)

{

{

	int cpu;

	power_trace = tr;

	power_trace = tr;





	trace_power_enabled = 1;

	trace_power_enabled = 1;

	tracing_power_register();

	tracing_power_register();





	for_each_cpu(cpu, cpu_possible_mask)

	tracing_reset_online_cpus(tr);

		tracing_reset(tr, cpu);

	return 0;

	return 0;

}

}

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