tracing: create automated trace defines

This patch lowers the number of places a developer must modify to add
new tracepoints. The current method to add a new tracepoint
into an existing system is to write the trace point macro in the
trace header with one of the macros TRACE_EVENT, TRACE_FORMAT or
DECLARE_TRACE, then they must add the same named item into the C file
with the macro DEFINE_TRACE(name) and then add the trace point.

This change cuts out the needing to add the DEFINE_TRACE(name).
Every file that uses the tracepoint must still include the trace/<type>.h
file, but the one C file must also add a define before the including
of that file.

 #define CREATE_TRACE_POINTS
 #include <trace/mytrace.h>

This will cause the trace/mytrace.h file to also produce the C code
necessary to implement the trace point.

Note, if more than one trace/<type>.h is used to create the C code
it is best to list them all together.

 #define CREATE_TRACE_POINTS
 #include <trace/foo.h>
 #include <trace/bar.h>
 #include <trace/fido.h>

Thanks to Mathieu Desnoyers and Christoph Hellwig for coming up with
the cleaner solution of the define above the includes over my first
design to have the C code include a "special" header.

This patch converts sched, irq and lockdep and skb to use this new
method.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Zhao Lei <zhaolei@cn.fujitsu.com>
Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

8 files changed, 9 insertions, 34 deletions

diff --git a/kernel/exit.c b/kernel/exit.c
index abf9cf3b95c..2fe9d2c7eee 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -56,10 +56,6 @@
 #include <asm/mmu_context.h>
 #include "cred-internals.h"
 
-DEFINE_TRACE(sched_process_free);
-DEFINE_TRACE(sched_process_exit);
-DEFINE_TRACE(sched_process_wait);
-
 static void exit_mm(struct task_struct * tsk);
 
 static void __unhash_process(struct task_struct *p)
diff --git a/kernel/fork.c b/kernel/fork.c
index b9e2edd0072..4bebf263923 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -83,8 +83,6 @@ DEFINE_PER_CPU(unsigned long, process_counts) = 0;
 
 __cacheline_aligned DEFINE_RWLOCK(tasklist_lock);  /* outer */
 
-DEFINE_TRACE(sched_process_fork);
-
 int nr_processes(void)
 {
 	int cpu;
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index d82142be8dd..983d8be8dff 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -17,9 +17,11 @@
 #include <linux/kernel_stat.h>
 #include <linux/rculist.h>
 #include <linux/hash.h>
-#include <trace/irq.h>
 #include <linux/bootmem.h>
 
+#define CREATE_TRACE_POINTS
+#include <trace/irq.h>
+
 #include "internals.h"
 
 /*
@@ -348,9 +350,6 @@ static void warn_no_thread(unsigned int irq, struct irqaction *action)
 	       "but no thread function available.", irq, action->name);
 }
 
-DEFINE_TRACE(irq_handler_entry);
-DEFINE_TRACE(irq_handler_exit);
-
 /**
  * handle_IRQ_event - irq action chain handler
  * @irq:	the interrupt number
diff --git a/kernel/kthread.c b/kernel/kthread.c
index 4ebaf8519ab..e1c76924545 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -21,9 +21,6 @@ static DEFINE_SPINLOCK(kthread_create_lock);
 static LIST_HEAD(kthread_create_list);
 struct task_struct *kthreadd_task;
 
-DEFINE_TRACE(sched_kthread_stop);
-DEFINE_TRACE(sched_kthread_stop_ret);
-
 struct kthread_create_info
 {
 	/* Information passed to kthread() from kthreadd. */
diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index c4582a6ea95..257f21a76c5 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -42,12 +42,14 @@
 #include <linux/hash.h>
 #include <linux/ftrace.h>
 #include <linux/stringify.h>
-#include <trace/lockdep.h>
 
 #include <asm/sections.h>
 
 #include "lockdep_internals.h"
 
+#define CREATE_TRACE_POINTS
+#include <trace/lockdep.h>
+
 #ifdef CONFIG_PROVE_LOCKING
 int prove_locking = 1;
 module_param(prove_locking, int, 0644);
@@ -2929,8 +2931,6 @@ void lock_set_class(struct lockdep_map *lock, const char *name,
 }
 EXPORT_SYMBOL_GPL(lock_set_class);
 
-DEFINE_TRACE(lock_acquire);
-
 /*
  * We are not always called with irqs disabled - do that here,
  * and also avoid lockdep recursion:
@@ -2957,8 +2957,6 @@ void lock_acquire(struct lockdep_map *lock, unsigned int subclass,
 }
 EXPORT_SYMBOL_GPL(lock_acquire);
 
-DEFINE_TRACE(lock_release);
-
 void lock_release(struct lockdep_map *lock, int nested,
 			  unsigned long ip)
 {
@@ -3061,8 +3059,6 @@ found_it:
 	put_lock_stats(stats);
 }
 
-DEFINE_TRACE(lock_acquired);
-
 static void
 __lock_acquired(struct lockdep_map *lock, unsigned long ip)
 {
@@ -3118,8 +3114,6 @@ found_it:
 	lock->ip = ip;
 }
 
-DEFINE_TRACE(lock_contended);
-
 void lock_contended(struct lockdep_map *lock, unsigned long ip)
 {
 	unsigned long flags;
diff --git a/kernel/sched.c b/kernel/sched.c
index 5724508c3b6..e6d4518d47e 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -72,13 +72,15 @@
 #include <linux/debugfs.h>
 #include <linux/ctype.h>
 #include <linux/ftrace.h>
-#include <trace/sched.h>
 
 #include <asm/tlb.h>
 #include <asm/irq_regs.h>
 
 #include "sched_cpupri.h"
 
+#define CREATE_TRACE_POINTS
+#include <trace/sched.h>
+
 /*
  * Convert user-nice values [ -20 ... 0 ... 19 ]
  * to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ],
@@ -118,12 +120,6 @@
  */
 #define RUNTIME_INF	((u64)~0ULL)
 
-DEFINE_TRACE(sched_wait_task);
-DEFINE_TRACE(sched_wakeup);
-DEFINE_TRACE(sched_wakeup_new);
-DEFINE_TRACE(sched_switch);
-DEFINE_TRACE(sched_migrate_task);
-
 #ifdef CONFIG_SMP
 
 static void double_rq_lock(struct rq *rq1, struct rq *rq2);
diff --git a/kernel/signal.c b/kernel/signal.c
index d8034737db4..1d5703ff003 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -41,8 +41,6 @@
 
 static struct kmem_cache *sigqueue_cachep;
 
-DEFINE_TRACE(sched_signal_send);
-
 static void __user *sig_handler(struct task_struct *t, int sig)
 {
 	return t->sighand->action[sig - 1].sa.sa_handler;
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 2fecefacdc5..a2d9b458ac2 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -186,9 +186,6 @@ EXPORT_SYMBOL(local_bh_enable_ip);
  */
 #define MAX_SOFTIRQ_RESTART 10
 
-DEFINE_TRACE(softirq_entry);
-DEFINE_TRACE(softirq_exit);
-
 asmlinkage void __do_softirq(void)
 {
 	struct softirq_action *h;