Commit 182e9f5f authored by Steven Rostedt's avatar Steven Rostedt Committed by Ingo Molnar
Browse files

ftrace: insert in the ftrace_preempt_disable()/enable() functions 



Impact: use new, consolidated APIs in ftrace plugins

This patch replaces the schedule safe preempt disable code with the
ftrace_preempt_disable() and ftrace_preempt_enable() safe functions.

Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 8f0a056f

kernel/trace/ring_buffer.c

+9 −18
Original line number Diff line number Diff line
@@ -16,6 +16,8 @@ 
#include <linux/list.h>

#include <linux/fs.h>



#include "trace.h"



/* Up this if you want to test the TIME_EXTENTS and normalization */

#define DEBUG_SHIFT 0
@@ -1122,8 +1124,7 @@ ring_buffer_lock_reserve(struct ring_buffer *buffer, 
		return NULL;



	/* If we are tracing schedule, we don't want to recurse */

	resched = need_resched();

	preempt_disable_notrace();

	resched = ftrace_preempt_disable();



	cpu = raw_smp_processor_id();
@@ -1154,10 +1155,7 @@ ring_buffer_lock_reserve(struct ring_buffer *buffer, 
	return event;



 out:

	if (resched)

		preempt_enable_notrace();

	else

		preempt_enable_notrace();

	ftrace_preempt_enable(resched);

	return NULL;

}
@@ -1199,12 +1197,9 @@ int ring_buffer_unlock_commit(struct ring_buffer *buffer, 
	/*

	 * Only the last preempt count needs to restore preemption.

	 */

	if (preempt_count() == 1) {

		if (per_cpu(rb_need_resched, cpu))

			preempt_enable_no_resched_notrace();

	if (preempt_count() == 1)

		ftrace_preempt_enable(per_cpu(rb_need_resched, cpu));

	else

			preempt_enable_notrace();

	} else

		preempt_enable_no_resched_notrace();



	return 0;
@@ -1237,8 +1232,7 @@ int ring_buffer_write(struct ring_buffer *buffer, 
	if (atomic_read(&buffer->record_disabled))

		return -EBUSY;



	resched = need_resched();

	preempt_disable_notrace();

	resched = ftrace_preempt_disable();



	cpu = raw_smp_processor_id();
@@ -1264,10 +1258,7 @@ int ring_buffer_write(struct ring_buffer *buffer, 


	ret = 0;

 out:

	if (resched)

		preempt_enable_no_resched_notrace();

	else

		preempt_enable_notrace();

	ftrace_preempt_enable(resched);



	return ret;

}

kernel/trace/trace.c

+2 −6
Original line number Diff line number Diff line
@@ -904,8 +904,7 @@ function_trace_call(unsigned long ip, unsigned long parent_ip) 
		return;



	pc = preempt_count();

	resched = need_resched();

	preempt_disable_notrace();

	resched = ftrace_preempt_disable();

	local_save_flags(flags);

	cpu = raw_smp_processor_id();

	data = tr->data[cpu];
@@ -915,10 +914,7 @@ function_trace_call(unsigned long ip, unsigned long parent_ip) 
		trace_function(tr, data, ip, parent_ip, flags, pc);



	atomic_dec(&data->disabled);

	if (resched)

		preempt_enable_no_resched_notrace();

	else

		preempt_enable_notrace();

	ftrace_preempt_enable(resched);

}



static struct ftrace_ops trace_ops __read_mostly =

kernel/trace/trace_sched_wakeup.c

+2 −11
Original line number Diff line number Diff line
@@ -50,8 +50,7 @@ wakeup_tracer_call(unsigned long ip, unsigned long parent_ip) 
		return;



	pc = preempt_count();

	resched = need_resched();

	preempt_disable_notrace();

	resched = ftrace_preempt_disable();



	cpu = raw_smp_processor_id();

	data = tr->data[cpu];
@@ -81,15 +80,7 @@ wakeup_tracer_call(unsigned long ip, unsigned long parent_ip) 
 out:

	atomic_dec(&data->disabled);



	/*

	 * To prevent recursion from the scheduler, if the

	 * resched flag was set before we entered, then

	 * don't reschedule.

	 */

	if (resched)

		preempt_enable_no_resched_notrace();

	else

		preempt_enable_notrace();

	ftrace_preempt_enable(resched);

}



static struct ftrace_ops trace_ops __read_mostly =

kernel/trace/trace_stack.c

+2 −6
Original line number Diff line number Diff line
@@ -107,8 +107,7 @@ stack_trace_call(unsigned long ip, unsigned long parent_ip) 
	if (unlikely(!ftrace_enabled || stack_trace_disabled))

		return;



	resched = need_resched();

	preempt_disable_notrace();

	resched = ftrace_preempt_disable();



	cpu = raw_smp_processor_id();

	/* no atomic needed, we only modify this variable by this cpu */
@@ -120,10 +119,7 @@ stack_trace_call(unsigned long ip, unsigned long parent_ip) 
 out:

	per_cpu(trace_active, cpu)--;

	/* prevent recursion in schedule */

	if (resched)

		preempt_enable_no_resched_notrace();

	else

		preempt_enable_notrace();

	ftrace_preempt_enable(resched);

}



static struct ftrace_ops trace_ops __read_mostly =