lockdep: Make the lock debug output more useful

The lock debug output in print_lock() has a few shortcomings:

 - It prints the hlock->acquire_ip field in %px and %pS format. That's
   redundant information.

 - It lacks information about the lock object itself. The lock class is
   not helpful to identify a particular instance of a lock.

Change the output so it prints:

 - hlock->instance to allow identification of a particular lock instance.

 - only the %pS format of hlock->ip_acquire which is sufficient to decode
   the actual code line with faddr2line.

The resulting output is:

3 locks held by a.out/31106:
#0: 00000000b0f753ba (&mm->mmap_sem){++++}, at: copy_process.part.41+0x10d5/0x1fe0
#1: 00000000ef64d539 (&mm->mmap_sem/1){+.+.}, at: copy_process.part.41+0x10fe/0x1fe0
#2: 00000000b41a282e (&mapping->i_mmap_rwsem){++++}, at: copy_process.part.41+0x12f2/0x1fe0

[ tglx: Massaged changelog ]

Signed-off-by: Tetsuo Handa <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Acked-by: David Rientjes <[email protected]>
Acked-by: Peter Zijlstra <[email protected]>
Cc: [email protected]
Cc: Borislav Petkov <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]

0 files changed, 0 insertions, 0 deletions