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
Cc: Steven Rostedt
Cc: =?ISO-8859-1?Q?T=F6r=F6k?= Edwin
Cc: Jason Baron
Cc: Frederic Weisbecker
LKML-Reference:
Signed-off-by: Ingo Molnar