tracing: add lockdep tracepoints for lock acquire/release

Augment the traces with lock names when lockdep is available:

 1)               |  down_read_trylock() {
 1)               |    _spin_lock_irqsave() {
 1)               |      /* lock_acquire: &sem->wait_lock */
 1)   4.201 us    |    }
 1)               |    _spin_unlock_irqrestore() {
 1)               |      /* lock_release: &sem->wait_lock */
 1)   3.523 us    |    }
 1)               |  /* lock_acquire: try read &mm->mmap_sem */
 1) + 13.386 us   |  }
 1)   1.635 us    |  find_vma();
 1)               |  handle_mm_fault() {
 1)               |    __do_fault() {
 1)               |      filemap_fault() {
 1)               |        find_lock_page() {
 1)               |          find_get_page() {
 1)               |            /* lock_acquire: read rcu_read_lock */
 1)               |            /* lock_release: rcu_read_lock */
 1)   5.697 us    |          }
 1)   8.158 us    |        }
 1) + 11.079 us   |      }
 1)               |      _spin_lock() {
 1)               |        /* lock_acquire: __pte_lockptr(page) */
 1)   3.949 us    |      }
 1)   1.460 us    |      page_add_file_rmap();
 1)               |      _spin_unlock() {
 1)               |        /* lock_release: __pte_lockptr(page) */
 1)   3.115 us    |      }
 1)               |      unlock_page() {
 1)   1.421 us    |        page_waitqueue();
 1)   1.220 us    |        __wake_up_bit();
 1)   6.519 us    |      }
 1) + 34.328 us   |    }
 1) + 37.452 us   |  }
 1)               |  up_read() {
 1)               |  /* lock_release: &mm->mmap_sem */
 1)               |    _spin_lock_irqsave() {
 1)               |      /* lock_acquire: &sem->wait_lock */
 1)   3.865 us    |    }
 1)               |    _spin_unlock_irqrestore() {
 1)               |      /* lock_release: &sem->wait_lock */
 1)   8.562 us    |    }
 1) + 17.370 us   |  }

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: =?ISO-8859-1?Q?T=F6r=F6k?= Edwin <edwintorok@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1236166375.5330.7209.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

include/trace/lockdep.h

@@ -0,0 +1,9 @@
+#ifndef _TRACE_LOCKDEP_H
+#define _TRACE_LOCKDEP_H
+
+#include <linux/lockdep.h>
+#include <linux/tracepoint.h>
+
+#include <trace/lockdep_event_types.h>
+
+#endif

include/trace/lockdep_event_types.h

@@ -0,0 +1,44 @@
+
+#ifndef TRACE_EVENT_FORMAT
+# error Do not include this file directly.
+# error Unless you know what you are doing.
+#endif
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM lock
+
+#ifdef CONFIG_LOCKDEP
+
+TRACE_FORMAT(lock_acquire,
+	TPPROTO(struct lockdep_map *lock, unsigned int subclass,
+		int trylock, int read, int check,
+		struct lockdep_map *next_lock, unsigned long ip),
+	TPARGS(lock, subclass, trylock, read, check, next_lock, ip),
+	TPFMT("%s%s%s", trylock ? "try " : "",
+		read ? "read " : "", lock->name)
+	);
+
+TRACE_FORMAT(lock_release,
+	TPPROTO(struct lockdep_map *lock, int nested, unsigned long ip),
+	TPARGS(lock, nested, ip),
+	TPFMT("%s", lock->name)
+	);
+
+#ifdef CONFIG_LOCK_STAT
+
+TRACE_FORMAT(lock_contended,
+	TPPROTO(struct lockdep_map *lock, unsigned long ip),
+	TPARGS(lock, ip),
+	TPFMT("%s", lock->name)
+	);
+
+TRACE_FORMAT(lock_acquired,
+	TPPROTO(struct lockdep_map *lock, unsigned long ip),
+	TPARGS(lock, ip),
+	TPFMT("%s", lock->name)
+	);
+
+#endif
+#endif
+
+#undef TRACE_SYSTEM

include/trace/trace_event_types.h

@@ -2,3 +2,4 @@
 
 #include <trace/sched_event_types.h>
 #include <trace/irq_event_types.h>
+#include <trace/lockdep_event_types.h>

include/trace/trace_events.h

@@ -2,3 +2,4 @@
 
 #include <trace/sched.h>
 #include <trace/irq.h>
+#include <trace/lockdep.h>