blob: a4969b47afc1e8120b149d22e73357393be2056b [file] [log] [blame]
Steven Rostedt81d68a92008-05-12 21:20:42 +02001/*
Wenji Huang73d8b8b2009-02-17 01:10:02 -05002 * trace irqs off critical timings
Steven Rostedt81d68a92008-05-12 21:20:42 +02003 *
4 * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
5 * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com>
6 *
7 * From code in the latency_tracer, that is:
8 *
9 * Copyright (C) 2004-2006 Ingo Molnar
10 * Copyright (C) 2004 William Lee Irwin III
11 */
12#include <linux/kallsyms.h>
13#include <linux/debugfs.h>
14#include <linux/uaccess.h>
15#include <linux/module.h>
16#include <linux/ftrace.h>
17#include <linux/fs.h>
18
19#include "trace.h"
20
21static struct trace_array *irqsoff_trace __read_mostly;
22static int tracer_enabled __read_mostly;
23
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +020024static DEFINE_PER_CPU(int, tracing_cpu);
25
Steven Rostedt89b2f972008-05-12 21:20:44 +020026static DEFINE_SPINLOCK(max_trace_lock);
27
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +020028enum {
29 TRACER_IRQS_OFF = (1 << 1),
30 TRACER_PREEMPT_OFF = (1 << 2),
31};
32
33static int trace_type __read_mostly;
34
Steven Rostedte9d25fe2009-03-04 22:15:30 -050035static int save_lat_flag;
36
Jiri Olsa62b915f2010-04-02 19:01:22 +020037static void stop_irqsoff_tracer(struct trace_array *tr, int graph);
38static int start_irqsoff_tracer(struct trace_array *tr, int graph);
39
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +020040#ifdef CONFIG_PREEMPT_TRACER
Ingo Molnare309b412008-05-12 21:20:51 +020041static inline int
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +020042preempt_trace(void)
43{
44 return ((trace_type & TRACER_PREEMPT_OFF) && preempt_count());
45}
46#else
47# define preempt_trace() (0)
48#endif
49
50#ifdef CONFIG_IRQSOFF_TRACER
Ingo Molnare309b412008-05-12 21:20:51 +020051static inline int
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +020052irq_trace(void)
53{
54 return ((trace_type & TRACER_IRQS_OFF) &&
55 irqs_disabled());
56}
57#else
58# define irq_trace() (0)
59#endif
60
Jiri Olsa62b915f2010-04-02 19:01:22 +020061#define TRACE_DISPLAY_GRAPH 1
62
63static struct tracer_opt trace_opts[] = {
64#ifdef CONFIG_FUNCTION_GRAPH_TRACER
65 /* display latency trace as call graph */
66 { TRACER_OPT(display-graph, TRACE_DISPLAY_GRAPH) },
67#endif
68 { } /* Empty entry */
69};
70
71static struct tracer_flags tracer_flags = {
72 .val = 0,
73 .opts = trace_opts,
74};
75
76#define is_graph() (tracer_flags.val & TRACE_DISPLAY_GRAPH)
77
Steven Rostedt81d68a92008-05-12 21:20:42 +020078/*
79 * Sequence count - we record it when starting a measurement and
80 * skip the latency if the sequence has changed - some other section
81 * did a maximum and could disturb our measurement with serial console
82 * printouts, etc. Truly coinciding maximum latencies should be rare
Lucas De Marchi25985ed2011-03-30 22:57:33 -030083 * and what happens together happens separately as well, so this doesn't
Steven Rostedt81d68a92008-05-12 21:20:42 +020084 * decrease the validity of the maximum found:
85 */
86static __cacheline_aligned_in_smp unsigned long max_sequence;
87
Steven Rostedt606576c2008-10-06 19:06:12 -040088#ifdef CONFIG_FUNCTION_TRACER
Steven Rostedt81d68a92008-05-12 21:20:42 +020089/*
Steven Rostedt5e6d2b92010-10-05 19:41:43 -040090 * Prologue for the preempt and irqs off function tracers.
91 *
92 * Returns 1 if it is OK to continue, and data->disabled is
93 * incremented.
94 * 0 if the trace is to be ignored, and data->disabled
95 * is kept the same.
96 *
97 * Note, this function is also used outside this ifdef but
98 * inside the #ifdef of the function graph tracer below.
99 * This is OK, since the function graph tracer is
100 * dependent on the function tracer.
Steven Rostedt81d68a92008-05-12 21:20:42 +0200101 */
Steven Rostedt5e6d2b92010-10-05 19:41:43 -0400102static int func_prolog_dec(struct trace_array *tr,
103 struct trace_array_cpu **data,
104 unsigned long *flags)
Steven Rostedt81d68a92008-05-12 21:20:42 +0200105{
Steven Rostedt81d68a92008-05-12 21:20:42 +0200106 long disabled;
107 int cpu;
108
Steven Rostedt361943a2008-05-12 21:20:44 +0200109 /*
110 * Does not matter if we preempt. We test the flags
111 * afterward, to see if irqs are disabled or not.
112 * If we preempt and get a false positive, the flags
113 * test will fail.
114 */
115 cpu = raw_smp_processor_id();
116 if (likely(!per_cpu(tracing_cpu, cpu)))
Steven Rostedt5e6d2b92010-10-05 19:41:43 -0400117 return 0;
Steven Rostedt81d68a92008-05-12 21:20:42 +0200118
Steven Rostedt5e6d2b92010-10-05 19:41:43 -0400119 local_save_flags(*flags);
Steven Rostedt361943a2008-05-12 21:20:44 +0200120 /* slight chance to get a false positive on tracing_cpu */
Steven Rostedt5e6d2b92010-10-05 19:41:43 -0400121 if (!irqs_disabled_flags(*flags))
122 return 0;
Steven Rostedt81d68a92008-05-12 21:20:42 +0200123
Steven Rostedt5e6d2b92010-10-05 19:41:43 -0400124 *data = tr->data[cpu];
125 disabled = atomic_inc_return(&(*data)->disabled);
Steven Rostedt81d68a92008-05-12 21:20:42 +0200126
127 if (likely(disabled == 1))
Steven Rostedt5e6d2b92010-10-05 19:41:43 -0400128 return 1;
129
130 atomic_dec(&(*data)->disabled);
131
132 return 0;
133}
134
135/*
136 * irqsoff uses its own tracer function to keep the overhead down:
137 */
138static void
139irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip)
140{
141 struct trace_array *tr = irqsoff_trace;
142 struct trace_array_cpu *data;
143 unsigned long flags;
144
145 if (!func_prolog_dec(tr, &data, &flags))
146 return;
147
148 trace_function(tr, ip, parent_ip, flags, preempt_count());
Steven Rostedt81d68a92008-05-12 21:20:42 +0200149
150 atomic_dec(&data->disabled);
151}
152
153static struct ftrace_ops trace_ops __read_mostly =
154{
155 .func = irqsoff_tracer_call,
156};
Steven Rostedt606576c2008-10-06 19:06:12 -0400157#endif /* CONFIG_FUNCTION_TRACER */
Steven Rostedt81d68a92008-05-12 21:20:42 +0200158
Jiri Olsa62b915f2010-04-02 19:01:22 +0200159#ifdef CONFIG_FUNCTION_GRAPH_TRACER
160static int irqsoff_set_flag(u32 old_flags, u32 bit, int set)
161{
162 int cpu;
163
164 if (!(bit & TRACE_DISPLAY_GRAPH))
165 return -EINVAL;
166
167 if (!(is_graph() ^ set))
168 return 0;
169
170 stop_irqsoff_tracer(irqsoff_trace, !set);
171
172 for_each_possible_cpu(cpu)
173 per_cpu(tracing_cpu, cpu) = 0;
174
175 tracing_max_latency = 0;
176 tracing_reset_online_cpus(irqsoff_trace);
177
178 return start_irqsoff_tracer(irqsoff_trace, set);
179}
180
181static int irqsoff_graph_entry(struct ftrace_graph_ent *trace)
182{
183 struct trace_array *tr = irqsoff_trace;
184 struct trace_array_cpu *data;
185 unsigned long flags;
Jiri Olsa62b915f2010-04-02 19:01:22 +0200186 int ret;
Jiri Olsa62b915f2010-04-02 19:01:22 +0200187 int pc;
188
Steven Rostedt5e6d2b92010-10-05 19:41:43 -0400189 if (!func_prolog_dec(tr, &data, &flags))
Jiri Olsa62b915f2010-04-02 19:01:22 +0200190 return 0;
191
Steven Rostedt5e6d2b92010-10-05 19:41:43 -0400192 pc = preempt_count();
193 ret = __trace_graph_entry(tr, trace, flags, pc);
Jiri Olsa62b915f2010-04-02 19:01:22 +0200194 atomic_dec(&data->disabled);
Steven Rostedt5e6d2b92010-10-05 19:41:43 -0400195
Jiri Olsa62b915f2010-04-02 19:01:22 +0200196 return ret;
197}
198
199static void irqsoff_graph_return(struct ftrace_graph_ret *trace)
200{
201 struct trace_array *tr = irqsoff_trace;
202 struct trace_array_cpu *data;
203 unsigned long flags;
Jiri Olsa62b915f2010-04-02 19:01:22 +0200204 int pc;
205
Steven Rostedt5e6d2b92010-10-05 19:41:43 -0400206 if (!func_prolog_dec(tr, &data, &flags))
Jiri Olsa62b915f2010-04-02 19:01:22 +0200207 return;
208
Steven Rostedt5e6d2b92010-10-05 19:41:43 -0400209 pc = preempt_count();
210 __trace_graph_return(tr, trace, flags, pc);
Jiri Olsa62b915f2010-04-02 19:01:22 +0200211 atomic_dec(&data->disabled);
212}
213
214static void irqsoff_trace_open(struct trace_iterator *iter)
215{
216 if (is_graph())
217 graph_trace_open(iter);
218
219}
220
221static void irqsoff_trace_close(struct trace_iterator *iter)
222{
223 if (iter->private)
224 graph_trace_close(iter);
225}
226
227#define GRAPH_TRACER_FLAGS (TRACE_GRAPH_PRINT_CPU | \
228 TRACE_GRAPH_PRINT_PROC)
229
230static enum print_line_t irqsoff_print_line(struct trace_iterator *iter)
231{
Jiri Olsa62b915f2010-04-02 19:01:22 +0200232 /*
233 * In graph mode call the graph tracer output function,
234 * otherwise go with the TRACE_FN event handler
235 */
236 if (is_graph())
Jiri Olsa0a772622010-09-23 14:00:52 +0200237 return print_graph_function_flags(iter, GRAPH_TRACER_FLAGS);
Jiri Olsa62b915f2010-04-02 19:01:22 +0200238
239 return TRACE_TYPE_UNHANDLED;
240}
241
242static void irqsoff_print_header(struct seq_file *s)
243{
Jiri Olsa0a772622010-09-23 14:00:52 +0200244 if (is_graph())
245 print_graph_headers_flags(s, GRAPH_TRACER_FLAGS);
246 else
Jiri Olsa62b915f2010-04-02 19:01:22 +0200247 trace_default_header(s);
248}
249
250static void
Jiri Olsa62b915f2010-04-02 19:01:22 +0200251__trace_function(struct trace_array *tr,
252 unsigned long ip, unsigned long parent_ip,
253 unsigned long flags, int pc)
254{
Jiri Olsa0a772622010-09-23 14:00:52 +0200255 if (is_graph())
256 trace_graph_function(tr, ip, parent_ip, flags, pc);
257 else
Jiri Olsa62b915f2010-04-02 19:01:22 +0200258 trace_function(tr, ip, parent_ip, flags, pc);
Jiri Olsa62b915f2010-04-02 19:01:22 +0200259}
260
261#else
262#define __trace_function trace_function
263
264static int irqsoff_set_flag(u32 old_flags, u32 bit, int set)
265{
266 return -EINVAL;
267}
268
269static int irqsoff_graph_entry(struct ftrace_graph_ent *trace)
270{
271 return -1;
272}
273
274static enum print_line_t irqsoff_print_line(struct trace_iterator *iter)
275{
276 return TRACE_TYPE_UNHANDLED;
277}
278
279static void irqsoff_graph_return(struct ftrace_graph_ret *trace) { }
280static void irqsoff_print_header(struct seq_file *s) { }
281static void irqsoff_trace_open(struct trace_iterator *iter) { }
282static void irqsoff_trace_close(struct trace_iterator *iter) { }
283#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
284
Steven Rostedt81d68a92008-05-12 21:20:42 +0200285/*
286 * Should this new latency be reported/recorded?
287 */
Ingo Molnare309b412008-05-12 21:20:51 +0200288static int report_latency(cycle_t delta)
Steven Rostedt81d68a92008-05-12 21:20:42 +0200289{
290 if (tracing_thresh) {
291 if (delta < tracing_thresh)
292 return 0;
293 } else {
294 if (delta <= tracing_max_latency)
295 return 0;
296 }
297 return 1;
298}
299
Ingo Molnare309b412008-05-12 21:20:51 +0200300static void
Steven Rostedt81d68a92008-05-12 21:20:42 +0200301check_critical_timing(struct trace_array *tr,
302 struct trace_array_cpu *data,
303 unsigned long parent_ip,
304 int cpu)
305{
Steven Rostedt89b2f972008-05-12 21:20:44 +0200306 cycle_t T0, T1, delta;
Steven Rostedt81d68a92008-05-12 21:20:42 +0200307 unsigned long flags;
Steven Rostedt38697052008-10-01 13:14:09 -0400308 int pc;
Steven Rostedt81d68a92008-05-12 21:20:42 +0200309
Steven Rostedt81d68a92008-05-12 21:20:42 +0200310 T0 = data->preempt_timestamp;
Ingo Molnar750ed1a2008-05-12 21:20:46 +0200311 T1 = ftrace_now(cpu);
Steven Rostedt81d68a92008-05-12 21:20:42 +0200312 delta = T1-T0;
313
314 local_save_flags(flags);
315
Steven Rostedt6450c1d2008-10-02 19:23:04 -0400316 pc = preempt_count();
317
Steven Rostedt81d68a92008-05-12 21:20:42 +0200318 if (!report_latency(delta))
319 goto out;
320
Ingo Molnarc7aafc52008-05-12 21:20:45 +0200321 spin_lock_irqsave(&max_trace_lock, flags);
Steven Rostedt81d68a92008-05-12 21:20:42 +0200322
Steven Rostedt89b2f972008-05-12 21:20:44 +0200323 /* check if we are still the max latency */
324 if (!report_latency(delta))
325 goto out_unlock;
326
Jiri Olsa62b915f2010-04-02 19:01:22 +0200327 __trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
Steven Rostedtcc51a0f2009-12-11 11:54:51 -0500328 /* Skip 5 functions to get to the irq/preempt enable function */
329 __trace_stack(tr, flags, 5, pc);
Steven Rostedt81d68a92008-05-12 21:20:42 +0200330
Steven Rostedt81d68a92008-05-12 21:20:42 +0200331 if (data->critical_sequence != max_sequence)
Steven Rostedt89b2f972008-05-12 21:20:44 +0200332 goto out_unlock;
Steven Rostedt81d68a92008-05-12 21:20:42 +0200333
Steven Rostedt81d68a92008-05-12 21:20:42 +0200334 data->critical_end = parent_ip;
335
Carsten Emdeb5130b12009-09-13 01:43:07 +0200336 if (likely(!is_tracing_stopped())) {
337 tracing_max_latency = delta;
338 update_max_tr_single(tr, current, cpu);
339 }
Steven Rostedt81d68a92008-05-12 21:20:42 +0200340
Steven Rostedt81d68a92008-05-12 21:20:42 +0200341 max_sequence++;
342
Steven Rostedt89b2f972008-05-12 21:20:44 +0200343out_unlock:
Ingo Molnarc7aafc52008-05-12 21:20:45 +0200344 spin_unlock_irqrestore(&max_trace_lock, flags);
Steven Rostedt89b2f972008-05-12 21:20:44 +0200345
Steven Rostedt81d68a92008-05-12 21:20:42 +0200346out:
347 data->critical_sequence = max_sequence;
Ingo Molnar750ed1a2008-05-12 21:20:46 +0200348 data->preempt_timestamp = ftrace_now(cpu);
Jiri Olsa62b915f2010-04-02 19:01:22 +0200349 __trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
Steven Rostedt81d68a92008-05-12 21:20:42 +0200350}
351
Ingo Molnare309b412008-05-12 21:20:51 +0200352static inline void
Steven Rostedt81d68a92008-05-12 21:20:42 +0200353start_critical_timing(unsigned long ip, unsigned long parent_ip)
354{
355 int cpu;
356 struct trace_array *tr = irqsoff_trace;
357 struct trace_array_cpu *data;
358 unsigned long flags;
359
360 if (likely(!tracer_enabled))
361 return;
362
Steven Rostedtc5f888c2008-05-12 21:20:55 +0200363 cpu = raw_smp_processor_id();
364
365 if (per_cpu(tracing_cpu, cpu))
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200366 return;
367
Steven Rostedt81d68a92008-05-12 21:20:42 +0200368 data = tr->data[cpu];
369
Steven Rostedtc5f888c2008-05-12 21:20:55 +0200370 if (unlikely(!data) || atomic_read(&data->disabled))
Steven Rostedt81d68a92008-05-12 21:20:42 +0200371 return;
372
373 atomic_inc(&data->disabled);
374
375 data->critical_sequence = max_sequence;
Ingo Molnar750ed1a2008-05-12 21:20:46 +0200376 data->preempt_timestamp = ftrace_now(cpu);
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200377 data->critical_start = parent_ip ? : ip;
Steven Rostedt81d68a92008-05-12 21:20:42 +0200378
379 local_save_flags(flags);
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200380
Jiri Olsa62b915f2010-04-02 19:01:22 +0200381 __trace_function(tr, ip, parent_ip, flags, preempt_count());
Steven Rostedt81d68a92008-05-12 21:20:42 +0200382
Steven Rostedtc5f888c2008-05-12 21:20:55 +0200383 per_cpu(tracing_cpu, cpu) = 1;
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200384
Steven Rostedt81d68a92008-05-12 21:20:42 +0200385 atomic_dec(&data->disabled);
386}
387
Ingo Molnare309b412008-05-12 21:20:51 +0200388static inline void
Steven Rostedt81d68a92008-05-12 21:20:42 +0200389stop_critical_timing(unsigned long ip, unsigned long parent_ip)
390{
391 int cpu;
392 struct trace_array *tr = irqsoff_trace;
393 struct trace_array_cpu *data;
394 unsigned long flags;
395
Steven Rostedtc5f888c2008-05-12 21:20:55 +0200396 cpu = raw_smp_processor_id();
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200397 /* Always clear the tracing cpu on stopping the trace */
Steven Rostedtc5f888c2008-05-12 21:20:55 +0200398 if (unlikely(per_cpu(tracing_cpu, cpu)))
399 per_cpu(tracing_cpu, cpu) = 0;
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200400 else
401 return;
402
403 if (!tracer_enabled)
Steven Rostedt81d68a92008-05-12 21:20:42 +0200404 return;
405
Steven Rostedt81d68a92008-05-12 21:20:42 +0200406 data = tr->data[cpu];
407
Steven Rostedt3928a8a2008-09-29 23:02:41 -0400408 if (unlikely(!data) ||
Steven Rostedt81d68a92008-05-12 21:20:42 +0200409 !data->critical_start || atomic_read(&data->disabled))
410 return;
411
412 atomic_inc(&data->disabled);
Steven Rostedtc5f888c2008-05-12 21:20:55 +0200413
Steven Rostedt81d68a92008-05-12 21:20:42 +0200414 local_save_flags(flags);
Jiri Olsa62b915f2010-04-02 19:01:22 +0200415 __trace_function(tr, ip, parent_ip, flags, preempt_count());
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200416 check_critical_timing(tr, data, parent_ip ? : ip, cpu);
Steven Rostedt81d68a92008-05-12 21:20:42 +0200417 data->critical_start = 0;
418 atomic_dec(&data->disabled);
419}
420
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200421/* start and stop critical timings used to for stoppage (in idle) */
Ingo Molnare309b412008-05-12 21:20:51 +0200422void start_critical_timings(void)
Steven Rostedt81d68a92008-05-12 21:20:42 +0200423{
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200424 if (preempt_trace() || irq_trace())
Steven Rostedt81d68a92008-05-12 21:20:42 +0200425 start_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
426}
Ingo Molnar1fe37102008-07-26 15:09:47 +0200427EXPORT_SYMBOL_GPL(start_critical_timings);
Steven Rostedt81d68a92008-05-12 21:20:42 +0200428
Ingo Molnare309b412008-05-12 21:20:51 +0200429void stop_critical_timings(void)
Steven Rostedt81d68a92008-05-12 21:20:42 +0200430{
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200431 if (preempt_trace() || irq_trace())
Steven Rostedt81d68a92008-05-12 21:20:42 +0200432 stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
433}
Ingo Molnar1fe37102008-07-26 15:09:47 +0200434EXPORT_SYMBOL_GPL(stop_critical_timings);
Steven Rostedt81d68a92008-05-12 21:20:42 +0200435
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200436#ifdef CONFIG_IRQSOFF_TRACER
Steven Rostedt81d68a92008-05-12 21:20:42 +0200437#ifdef CONFIG_PROVE_LOCKING
Ingo Molnare309b412008-05-12 21:20:51 +0200438void time_hardirqs_on(unsigned long a0, unsigned long a1)
Steven Rostedt81d68a92008-05-12 21:20:42 +0200439{
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200440 if (!preempt_trace() && irq_trace())
Steven Rostedt81d68a92008-05-12 21:20:42 +0200441 stop_critical_timing(a0, a1);
442}
443
Ingo Molnare309b412008-05-12 21:20:51 +0200444void time_hardirqs_off(unsigned long a0, unsigned long a1)
Steven Rostedt81d68a92008-05-12 21:20:42 +0200445{
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200446 if (!preempt_trace() && irq_trace())
Steven Rostedt81d68a92008-05-12 21:20:42 +0200447 start_critical_timing(a0, a1);
448}
449
450#else /* !CONFIG_PROVE_LOCKING */
451
452/*
453 * Stubs:
454 */
455
Steven Rostedt81d68a92008-05-12 21:20:42 +0200456void trace_softirqs_on(unsigned long ip)
457{
458}
459
460void trace_softirqs_off(unsigned long ip)
461{
462}
463
Ingo Molnare309b412008-05-12 21:20:51 +0200464inline void print_irqtrace_events(struct task_struct *curr)
Steven Rostedt81d68a92008-05-12 21:20:42 +0200465{
466}
467
468/*
469 * We are only interested in hardirq on/off events:
470 */
Ingo Molnare309b412008-05-12 21:20:51 +0200471void trace_hardirqs_on(void)
Steven Rostedt81d68a92008-05-12 21:20:42 +0200472{
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200473 if (!preempt_trace() && irq_trace())
Steven Rostedt81d68a92008-05-12 21:20:42 +0200474 stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
475}
476EXPORT_SYMBOL(trace_hardirqs_on);
477
Ingo Molnare309b412008-05-12 21:20:51 +0200478void trace_hardirqs_off(void)
Steven Rostedt81d68a92008-05-12 21:20:42 +0200479{
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200480 if (!preempt_trace() && irq_trace())
Steven Rostedt81d68a92008-05-12 21:20:42 +0200481 start_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
482}
483EXPORT_SYMBOL(trace_hardirqs_off);
484
Ingo Molnare309b412008-05-12 21:20:51 +0200485void trace_hardirqs_on_caller(unsigned long caller_addr)
Steven Rostedt81d68a92008-05-12 21:20:42 +0200486{
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200487 if (!preempt_trace() && irq_trace())
Steven Rostedt81d68a92008-05-12 21:20:42 +0200488 stop_critical_timing(CALLER_ADDR0, caller_addr);
489}
490EXPORT_SYMBOL(trace_hardirqs_on_caller);
491
Ingo Molnare309b412008-05-12 21:20:51 +0200492void trace_hardirqs_off_caller(unsigned long caller_addr)
Steven Rostedt81d68a92008-05-12 21:20:42 +0200493{
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200494 if (!preempt_trace() && irq_trace())
Steven Rostedt81d68a92008-05-12 21:20:42 +0200495 start_critical_timing(CALLER_ADDR0, caller_addr);
496}
497EXPORT_SYMBOL(trace_hardirqs_off_caller);
498
499#endif /* CONFIG_PROVE_LOCKING */
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200500#endif /* CONFIG_IRQSOFF_TRACER */
501
502#ifdef CONFIG_PREEMPT_TRACER
Ingo Molnare309b412008-05-12 21:20:51 +0200503void trace_preempt_on(unsigned long a0, unsigned long a1)
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200504{
Steven Rostedt1e01cb02008-07-15 09:53:37 -0400505 if (preempt_trace())
506 stop_critical_timing(a0, a1);
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200507}
508
Ingo Molnare309b412008-05-12 21:20:51 +0200509void trace_preempt_off(unsigned long a0, unsigned long a1)
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200510{
Steven Rostedt1e01cb02008-07-15 09:53:37 -0400511 if (preempt_trace())
512 start_critical_timing(a0, a1);
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200513}
514#endif /* CONFIG_PREEMPT_TRACER */
Steven Rostedt81d68a92008-05-12 21:20:42 +0200515
Jiri Olsa62b915f2010-04-02 19:01:22 +0200516static int start_irqsoff_tracer(struct trace_array *tr, int graph)
Steven Rostedt81d68a92008-05-12 21:20:42 +0200517{
Jiri Olsa62b915f2010-04-02 19:01:22 +0200518 int ret = 0;
519
520 if (!graph)
521 ret = register_ftrace_function(&trace_ops);
522 else
523 ret = register_ftrace_graph(&irqsoff_graph_return,
524 &irqsoff_graph_entry);
525
526 if (!ret && tracing_is_enabled())
Steven Rostedt90369902008-11-05 16:05:44 -0500527 tracer_enabled = 1;
Steven Rostedt94523e82009-01-22 11:18:06 -0500528 else
Steven Rostedt90369902008-11-05 16:05:44 -0500529 tracer_enabled = 0;
Jiri Olsa62b915f2010-04-02 19:01:22 +0200530
531 return ret;
Steven Rostedt81d68a92008-05-12 21:20:42 +0200532}
533
Jiri Olsa62b915f2010-04-02 19:01:22 +0200534static void stop_irqsoff_tracer(struct trace_array *tr, int graph)
Steven Rostedt81d68a92008-05-12 21:20:42 +0200535{
Steven Rostedt81d68a92008-05-12 21:20:42 +0200536 tracer_enabled = 0;
Jiri Olsa62b915f2010-04-02 19:01:22 +0200537
538 if (!graph)
539 unregister_ftrace_function(&trace_ops);
540 else
541 unregister_ftrace_graph();
Steven Rostedt81d68a92008-05-12 21:20:42 +0200542}
543
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200544static void __irqsoff_tracer_init(struct trace_array *tr)
Steven Rostedt81d68a92008-05-12 21:20:42 +0200545{
Steven Rostedte9d25fe2009-03-04 22:15:30 -0500546 save_lat_flag = trace_flags & TRACE_ITER_LATENCY_FMT;
547 trace_flags |= TRACE_ITER_LATENCY_FMT;
548
Steven Rostedt745b1622009-01-15 23:40:11 -0500549 tracing_max_latency = 0;
Steven Rostedt81d68a92008-05-12 21:20:42 +0200550 irqsoff_trace = tr;
Steven Rostedtc5f888c2008-05-12 21:20:55 +0200551 /* make sure that the tracer is visible */
Steven Rostedt81d68a92008-05-12 21:20:42 +0200552 smp_wmb();
Steven Rostedt2f26ebd2009-09-01 11:06:29 -0400553 tracing_reset_online_cpus(tr);
Jiri Olsa62b915f2010-04-02 19:01:22 +0200554
555 if (start_irqsoff_tracer(tr, is_graph()))
556 printk(KERN_ERR "failed to start irqsoff tracer\n");
Steven Rostedt81d68a92008-05-12 21:20:42 +0200557}
558
559static void irqsoff_tracer_reset(struct trace_array *tr)
560{
Jiri Olsa62b915f2010-04-02 19:01:22 +0200561 stop_irqsoff_tracer(tr, is_graph());
Steven Rostedte9d25fe2009-03-04 22:15:30 -0500562
563 if (!save_lat_flag)
564 trace_flags &= ~TRACE_ITER_LATENCY_FMT;
Steven Rostedt81d68a92008-05-12 21:20:42 +0200565}
566
Steven Rostedt90369902008-11-05 16:05:44 -0500567static void irqsoff_tracer_start(struct trace_array *tr)
568{
Steven Rostedt90369902008-11-05 16:05:44 -0500569 tracer_enabled = 1;
Steven Rostedt90369902008-11-05 16:05:44 -0500570}
571
572static void irqsoff_tracer_stop(struct trace_array *tr)
573{
574 tracer_enabled = 0;
Steven Rostedt81d68a92008-05-12 21:20:42 +0200575}
576
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200577#ifdef CONFIG_IRQSOFF_TRACER
Frederic Weisbecker1c800252008-11-16 05:57:26 +0100578static int irqsoff_tracer_init(struct trace_array *tr)
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200579{
580 trace_type = TRACER_IRQS_OFF;
581
582 __irqsoff_tracer_init(tr);
Frederic Weisbecker1c800252008-11-16 05:57:26 +0100583 return 0;
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200584}
Steven Rostedt81d68a92008-05-12 21:20:42 +0200585static struct tracer irqsoff_tracer __read_mostly =
586{
587 .name = "irqsoff",
588 .init = irqsoff_tracer_init,
589 .reset = irqsoff_tracer_reset,
Steven Rostedt90369902008-11-05 16:05:44 -0500590 .start = irqsoff_tracer_start,
591 .stop = irqsoff_tracer_stop,
Steven Rostedt81d68a92008-05-12 21:20:42 +0200592 .print_max = 1,
Jiri Olsa62b915f2010-04-02 19:01:22 +0200593 .print_header = irqsoff_print_header,
594 .print_line = irqsoff_print_line,
595 .flags = &tracer_flags,
596 .set_flag = irqsoff_set_flag,
Steven Rostedt60a11772008-05-12 21:20:44 +0200597#ifdef CONFIG_FTRACE_SELFTEST
598 .selftest = trace_selftest_startup_irqsoff,
599#endif
Jiri Olsa62b915f2010-04-02 19:01:22 +0200600 .open = irqsoff_trace_open,
601 .close = irqsoff_trace_close,
KOSAKI Motohiroef710e12010-07-01 14:34:35 +0900602 .use_max_tr = 1,
Steven Rostedt81d68a92008-05-12 21:20:42 +0200603};
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200604# define register_irqsoff(trace) register_tracer(&trace)
605#else
606# define register_irqsoff(trace) do { } while (0)
607#endif
608
609#ifdef CONFIG_PREEMPT_TRACER
Frederic Weisbecker1c800252008-11-16 05:57:26 +0100610static int preemptoff_tracer_init(struct trace_array *tr)
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200611{
612 trace_type = TRACER_PREEMPT_OFF;
613
614 __irqsoff_tracer_init(tr);
Frederic Weisbecker1c800252008-11-16 05:57:26 +0100615 return 0;
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200616}
617
618static struct tracer preemptoff_tracer __read_mostly =
619{
620 .name = "preemptoff",
621 .init = preemptoff_tracer_init,
622 .reset = irqsoff_tracer_reset,
Steven Rostedt90369902008-11-05 16:05:44 -0500623 .start = irqsoff_tracer_start,
624 .stop = irqsoff_tracer_stop,
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200625 .print_max = 1,
Jiri Olsa62b915f2010-04-02 19:01:22 +0200626 .print_header = irqsoff_print_header,
627 .print_line = irqsoff_print_line,
628 .flags = &tracer_flags,
629 .set_flag = irqsoff_set_flag,
Steven Rostedt60a11772008-05-12 21:20:44 +0200630#ifdef CONFIG_FTRACE_SELFTEST
631 .selftest = trace_selftest_startup_preemptoff,
632#endif
Jiri Olsa62b915f2010-04-02 19:01:22 +0200633 .open = irqsoff_trace_open,
634 .close = irqsoff_trace_close,
KOSAKI Motohiroef710e12010-07-01 14:34:35 +0900635 .use_max_tr = 1,
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200636};
637# define register_preemptoff(trace) register_tracer(&trace)
638#else
639# define register_preemptoff(trace) do { } while (0)
640#endif
641
642#if defined(CONFIG_IRQSOFF_TRACER) && \
643 defined(CONFIG_PREEMPT_TRACER)
644
Frederic Weisbecker1c800252008-11-16 05:57:26 +0100645static int preemptirqsoff_tracer_init(struct trace_array *tr)
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200646{
647 trace_type = TRACER_IRQS_OFF | TRACER_PREEMPT_OFF;
648
649 __irqsoff_tracer_init(tr);
Frederic Weisbecker1c800252008-11-16 05:57:26 +0100650 return 0;
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200651}
652
653static struct tracer preemptirqsoff_tracer __read_mostly =
654{
655 .name = "preemptirqsoff",
656 .init = preemptirqsoff_tracer_init,
657 .reset = irqsoff_tracer_reset,
Steven Rostedt90369902008-11-05 16:05:44 -0500658 .start = irqsoff_tracer_start,
659 .stop = irqsoff_tracer_stop,
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200660 .print_max = 1,
Jiri Olsa62b915f2010-04-02 19:01:22 +0200661 .print_header = irqsoff_print_header,
662 .print_line = irqsoff_print_line,
663 .flags = &tracer_flags,
664 .set_flag = irqsoff_set_flag,
Steven Rostedt60a11772008-05-12 21:20:44 +0200665#ifdef CONFIG_FTRACE_SELFTEST
666 .selftest = trace_selftest_startup_preemptirqsoff,
667#endif
Jiri Olsa62b915f2010-04-02 19:01:22 +0200668 .open = irqsoff_trace_open,
669 .close = irqsoff_trace_close,
KOSAKI Motohiroef710e12010-07-01 14:34:35 +0900670 .use_max_tr = 1,
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200671};
672
673# define register_preemptirqsoff(trace) register_tracer(&trace)
674#else
675# define register_preemptirqsoff(trace) do { } while (0)
676#endif
Steven Rostedt81d68a92008-05-12 21:20:42 +0200677
678__init static int init_irqsoff_tracer(void)
679{
Steven Rostedt6cd8a4b2008-05-12 21:20:42 +0200680 register_irqsoff(irqsoff_tracer);
681 register_preemptoff(preemptoff_tracer);
682 register_preemptirqsoff(preemptirqsoff_tracer);
Steven Rostedt81d68a92008-05-12 21:20:42 +0200683
684 return 0;
685}
686device_initcall(init_irqsoff_tracer);