Commit 6d9b3fa5 authored by Steven Rostedt (Red Hat)'s avatar Steven Rostedt (Red Hat) Committed by Steven Rostedt
Browse files

tracing: Move tracing_max_latency into trace_array 



In preparation for letting the latency tracers be used by instances,
remove the global tracing_max_latency variable and add a max_latency
field to the trace_array that the latency tracers will now use.

Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
parent 4104d326

kernel/trace/trace.c

+6 −8
Original line number Diff line number Diff line
@@ -982,8 +982,6 @@ static arch_spinlock_t ftrace_max_lock = 
unsigned long __read_mostly	tracing_thresh;



#ifdef CONFIG_TRACER_MAX_TRACE

unsigned long __read_mostly	tracing_max_latency;



/*

 * Copy the new maximum trace into the separate maximum-trace

 * structure. (this way the maximum trace is permanently saved,
@@ -1000,7 +998,7 @@ __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) 
	max_buf->cpu = cpu;

	max_buf->time_start = data->preempt_timestamp;



	max_data->saved_latency = tracing_max_latency;

	max_data->saved_latency = tr->max_latency;

	max_data->critical_start = data->critical_start;

	max_data->critical_end = data->critical_end;
@@ -6328,6 +6326,11 @@ init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) 
	trace_create_file("tracing_on", 0644, d_tracer,

			  tr, &rb_simple_fops);



#ifdef CONFIG_TRACER_MAX_TRACE

	trace_create_file("tracing_max_latency", 0644, d_tracer,

			&tr->max_latency, &tracing_max_lat_fops);

#endif



	if (ftrace_create_function_files(tr, d_tracer))

		WARN(1, "Could not allocate function filter files");
@@ -6353,11 +6356,6 @@ static __init int tracer_init_debugfs(void) 


	init_tracer_debugfs(&global_trace, d_tracer);



#ifdef CONFIG_TRACER_MAX_TRACE

	trace_create_file("tracing_max_latency", 0644, d_tracer,

			&tracing_max_latency, &tracing_max_lat_fops);

#endif



	trace_create_file("tracing_thresh", 0644, d_tracer,

			&tracing_thresh, &tracing_max_lat_fops);

kernel/trace/trace.h

+1 −2
Original line number Diff line number Diff line
@@ -190,6 +190,7 @@ struct trace_array { 
	 */

	struct trace_buffer	max_buffer;

	bool			allocated_snapshot;

	unsigned long		max_latency;

#endif

	int			buffer_disabled;

#ifdef CONFIG_FTRACE_SYSCALLS
@@ -599,8 +600,6 @@ extern unsigned long nsecs_to_usecs(unsigned long nsecs); 
extern unsigned long tracing_thresh;



#ifdef CONFIG_TRACER_MAX_TRACE

extern unsigned long tracing_max_latency;



void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);

void update_max_tr_single(struct trace_array *tr,

			  struct task_struct *tsk, int cpu);

kernel/trace/trace_irqsoff.c

+7 −7
Original line number Diff line number Diff line
@@ -170,7 +170,7 @@ irqsoff_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) 
	for_each_possible_cpu(cpu)

		per_cpu(tracing_cpu, cpu) = 0;



	tracing_max_latency = 0;

	tr->max_latency = 0;

	tracing_reset_online_cpus(&irqsoff_trace->trace_buffer);



	return start_irqsoff_tracer(irqsoff_trace, set);
@@ -297,13 +297,13 @@ static void irqsoff_print_header(struct seq_file *s) 
/*

 * Should this new latency be reported/recorded?

 */

static int report_latency(cycle_t delta)

static int report_latency(struct trace_array *tr, cycle_t delta)

{

	if (tracing_thresh) {

		if (delta < tracing_thresh)

			return 0;

	} else {

		if (delta <= tracing_max_latency)

		if (delta <= tr->max_latency)

			return 0;

	}

	return 1;
@@ -327,13 +327,13 @@ check_critical_timing(struct trace_array *tr, 


	pc = preempt_count();



	if (!report_latency(delta))

	if (!report_latency(tr, delta))

		goto out;



	raw_spin_lock_irqsave(&max_trace_lock, flags);



	/* check if we are still the max latency */

	if (!report_latency(delta))

	if (!report_latency(tr, delta))

		goto out_unlock;



	__trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
@@ -346,7 +346,7 @@ check_critical_timing(struct trace_array *tr, 
	data->critical_end = parent_ip;



	if (likely(!is_tracing_stopped())) {

		tracing_max_latency = delta;

		tr->max_latency = delta;

		update_max_tr_single(tr, current, cpu);

	}
@@ -605,7 +605,7 @@ static void __irqsoff_tracer_init(struct trace_array *tr) 
	set_tracer_flag(tr, TRACE_ITER_OVERWRITE, 1);

	set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, 1);



	tracing_max_latency = 0;

	tr->max_latency = 0;

	irqsoff_trace = tr;

	/* make sure that the tracer is visible */

	smp_wmb();

kernel/trace/trace_sched_wakeup.c

+6 −6
Original line number Diff line number Diff line
@@ -218,7 +218,7 @@ wakeup_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) 
	stop_func_tracer(tr, !set);



	wakeup_reset(wakeup_trace);

	tracing_max_latency = 0;

	tr->max_latency = 0;



	return start_func_tracer(tr, set);

}
@@ -344,13 +344,13 @@ static void wakeup_print_header(struct seq_file *s) 
/*

 * Should this new latency be reported/recorded?

 */

static int report_latency(cycle_t delta)

static int report_latency(struct trace_array *tr, cycle_t delta)

{

	if (tracing_thresh) {

		if (delta < tracing_thresh)

			return 0;

	} else {

		if (delta <= tracing_max_latency)

		if (delta <= tr->max_latency)

			return 0;

	}

	return 1;
@@ -418,11 +418,11 @@ probe_wakeup_sched_switch(void *ignore, 
	T1 = ftrace_now(cpu);

	delta = T1-T0;



	if (!report_latency(delta))

	if (!report_latency(wakeup_trace, delta))

		goto out_unlock;



	if (likely(!is_tracing_stopped())) {

		tracing_max_latency = delta;

		wakeup_trace->max_latency = delta;

		update_max_tr(wakeup_trace, wakeup_task, wakeup_cpu);

	}
@@ -609,7 +609,7 @@ static int __wakeup_tracer_init(struct trace_array *tr) 
	set_tracer_flag(tr, TRACE_ITER_OVERWRITE, 1);

	set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, 1);



	tracing_max_latency = 0;

	tr->max_latency = 0;

	wakeup_trace = tr;

	ftrace_init_array_ops(tr, wakeup_tracer_call);

	start_wakeup_tracer(tr);

kernel/trace/trace_selftest.c

+13 −13
Original line number Diff line number Diff line
@@ -807,7 +807,7 @@ out: 
int

trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr)

{

	unsigned long save_max = tracing_max_latency;

	unsigned long save_max = tr->max_latency;

	unsigned long count;

	int ret;
@@ -819,7 +819,7 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr) 
	}



	/* reset the max latency */

	tracing_max_latency = 0;

	tr->max_latency = 0;

	/* disable interrupts for a bit */

	local_irq_disable();

	udelay(100);
@@ -846,7 +846,7 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr) 
		ret = -1;

	}



	tracing_max_latency = save_max;

	tr->max_latency = save_max;



	return ret;

}
@@ -856,7 +856,7 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr) 
int

trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr)

{

	unsigned long save_max = tracing_max_latency;

	unsigned long save_max = tr->max_latency;

	unsigned long count;

	int ret;
@@ -881,7 +881,7 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr) 
	}



	/* reset the max latency */

	tracing_max_latency = 0;

	tr->max_latency = 0;

	/* disable preemption for a bit */

	preempt_disable();

	udelay(100);
@@ -908,7 +908,7 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr) 
		ret = -1;

	}



	tracing_max_latency = save_max;

	tr->max_latency = save_max;



	return ret;

}
@@ -918,7 +918,7 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr) 
int

trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *tr)

{

	unsigned long save_max = tracing_max_latency;

	unsigned long save_max = tr->max_latency;

	unsigned long count;

	int ret;
@@ -943,7 +943,7 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array * 
	}



	/* reset the max latency */

	tracing_max_latency = 0;

	tr->max_latency = 0;



	/* disable preemption and interrupts for a bit */

	preempt_disable();
@@ -978,7 +978,7 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array * 
	}



	/* do the test by disabling interrupts first this time */

	tracing_max_latency = 0;

	tr->max_latency = 0;

	tracing_start();

	trace->start(tr);
@@ -1009,7 +1009,7 @@ out: 
	tracing_start();

out_no_start:

	trace->reset(tr);

	tracing_max_latency = save_max;

	tr->max_latency = save_max;



	return ret;

}
@@ -1062,7 +1062,7 @@ static int trace_wakeup_test_thread(void *data) 
int

trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr)

{

	unsigned long save_max = tracing_max_latency;

	unsigned long save_max = tr->max_latency;

	struct task_struct *p;

	struct completion is_ready;

	unsigned long count;
@@ -1088,7 +1088,7 @@ trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr) 
	}



	/* reset the max latency */

	tracing_max_latency = 0;

	tr->max_latency = 0;



	while (p->on_rq) {

		/*
@@ -1118,7 +1118,7 @@ trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr) 
	trace->reset(tr);

	tracing_start();



	tracing_max_latency = save_max;

	tr->max_latency = save_max;



	/* kill the thread */

	kthread_stop(p);

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