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Subject[PATCH 0/5] lockdep: Add information of file and line to lockdep_map
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There are a lot of lock instances with same names (e.g. port_lock).
This patch series add __FILE__ and __LINE__ to lockdep_map,
and these will be used for trace lock events.

Example use from perf lock map:

| 0xffffea0004c992b8: __pte_lockptr(page) (src: include/linux/mm.h, line: 952)
| 0xffffea0004b112b8: __pte_lockptr(page) (src: include/linux/mm.h, line: 952)
| 0xffffea0004a3f2b8: __pte_lockptr(page) (src: include/linux/mm.h, line: 952)
| 0xffffea0004cd5228: __pte_lockptr(page) (src: include/linux/mm.h, line: 952)
| 0xffff8800b91e2b28: &sb->s_type->i_lock_key (src: fs/inode.c, line: 166)
| 0xffff8800bb9d7ae0: key (src: kernel/wait.c, line: 16)
| 0xffff8800aa07dae0: &dentry->d_lock (src: fs/dcache.c, line: 944)
| 0xffff8800b07fbae0: &dentry->d_lock (src: fs/dcache.c, line: 944)
| 0xffff8800b07f3ae0: &dentry->d_lock (src: fs/dcache.c, line: 944)
| 0xffff8800bf15fae0: &sighand->siglock (src: kernel/fork.c, line: 1490)
| 0xffff8800b90f7ae0: &dentry->d_lock (src: fs/dcache.c, line: 944)
| ...

(This output of perf lock map is produced by my local version,
I'll send this later.)

And sadly, as Peter Zijlstra predicted, this produces certain overhead.

Before appling this series:
| % sudo ./perf lock rec perf bench sched messaging
| # Running sched/messaging benchmark...
| # 20 sender and receiver processes per group
| # 10 groups == 400 processes run
|
| Total time: 3.834 [sec]
After:
sudo ./perf lock rec perf bench sched messaging
| # Running sched/messaging benchmark...
| # 20 sender and receiver processes per group
| # 10 groups == 400 processes run
|
| Total time: 5.415 [sec]
| [ perf record: Woken up 0 times to write data ]
| [ perf record: Captured and wrote 53.512 MB perf.data (~2337993 samples) ]

But raw exec of perf bench sched messaging is this:
| % perf bench sched messaging
| # Running sched/messaging benchmark...
| # 20 sender and receiver processes per group
| # 10 groups == 400 processes run
|
| Total time: 0.498 [sec]

Tracing lock events already produces amount of overhead.
I think the overhead produced by this series is not a fatal problem,
radically optimization is required...

Could you merge this into perf/lock branch, Ingo?

Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg Kroah-Hartman <gregkh@suse.de>

Hitoshi Mitake (5):
lockdep: Add file and line to initialize sequence of spin and rw lock
lockdep: Add file and line to initialize sequence of rwsem
lockdep: Add file and line to initialize sequence of rwsem
lockdep: Add file and line to initialize sequence of mutex
lockdep: Fix the way to initialize class_mutex for information of
file and line

arch/x86/include/asm/rwsem.h | 9 +++++++--
drivers/base/class.c | 3 ++-
include/linux/mutex-debug.h | 2 +-
include/linux/mutex.h | 12 +++++++++---
include/linux/rwsem-spinlock.h | 11 ++++++++---
include/linux/spinlock.h | 12 ++++++++----
include/linux/spinlock_types.h | 12 ++++++++++--
kernel/mutex-debug.c | 5 +++--
kernel/mutex-debug.h | 3 ++-
kernel/mutex.c | 5 +++--
kernel/mutex.h | 2 +-
lib/rwsem-spinlock.c | 5 +++--
lib/rwsem.c | 5 +++--
lib/spinlock_debug.c | 10 ++++++----
14 files changed, 66 insertions(+), 30 deletions(-)



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