Commit e289faa9 authored by JINHO LIM's avatar JINHO LIM Committed by Todd Kjos
Browse files

ANDROID: vendor_hooks: set debugging data when rt_mutex is working

We already applied the 'vendor hook' for Dtask Debugging Information
in below issue.
(https://issuetracker.google.com/issues/162776704

)

There are vendor hook call in mutex and rw_semaphore, but not for rt_mutex
Please refer to description in details as below,

1. Description
This feature writes rt mutex lock waiting information
on the task_struct structure. We can check mutex information and
mutex owner through the kernel log and custom analysis tools.
Like the previous feature in mutex and rw semaphore,
added data can be checked by ramdump analysis.

2. Vendor Hook Position
1) VENDOR_DATA
  - struct task_struct in sched.h

    VENDOR_DATA_ARRAY(2)

    [0] : type   // RTmutex (Mutex, Rwsem, ...)
    [1] : pointer   // address of lock
2) VENDOR_HOOKs
  - __rt_mutex_slowlock() in kernel/locking/rtmutex.c

3. Example
 - SysRq-w in kernel log
...
[   54.164463] [3:  kworker/u16:3:  253] kworker/3:2     D12736   418      2 0x00000228
[   54.164497] [3:  kworker/u16:3:  253] RTmutex: 0xffffffc051fa3ae8: owner[sh :9003]

[   54.167812] [3:  kworker/u16:3:  253] sh              D12848  9003   6900 0x04000200
[   54.167824] [3:  kworker/u16:3:  253] RTmutex: 0xffffffc051fa3b08: owner[kworker/3:2 :418]
...

Bug: 186567468

Signed-off-by: default avatarJINHO LIM <jordan.lim@samsung.com>
Change-Id: I93f9753be0b2c1fa1a6eaea09379d54c31d1ebcf
parent 75615149
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