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Commit ce3a9669 authored by Mauro Carvalho Chehab's avatar Mauro Carvalho Chehab Committed by Jonathan Corbet
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robust-futex-ABI.txt: standardize document format 



Each text file under Documentation follows a different
format. Some doesn't even have titles!

Change its representation to follow the adopted standard,
using ReST markups for it to be parseable by Sphinx:

- promote document title;
- use :Author: for authorship;
- mark literal blocks;
- add blank lines.

Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: default avatarJonathan Corbet <corbet@lwn.net>
parent 317a8455

Documentation/robust-futex-ABI.txt

+9 −5
Original line number Diff line number Diff line 
Started by Paul Jackson <pj@sgi.com>



====================

The robust futex ABI

--------------------

====================



:Author: Started by Paul Jackson <pj@sgi.com>





Robust_futexes provide a mechanism that is used in addition to normal

futexes, for kernel assist of cleanup of held locks on task exit.
@@ -32,7 +34,7 @@ probably causing deadlock or other such failure of the other threads 
waiting on the same locks.



A thread that anticipates possibly using robust_futexes should first

issue the system call:

issue the system call::



    asmlinkage long

    sys_set_robust_list(struct robust_list_head __user *head, size_t len);
@@ -91,7 +93,7 @@ that lock using the futex mechanism. 
When a thread has invoked the above system call to indicate it

anticipates using robust_futexes, the kernel stores the passed in 'head'

pointer for that task.  The task may retrieve that value later on by

using the system call:

using the system call::



    asmlinkage long

    sys_get_robust_list(int pid, struct robust_list_head __user **head_ptr,
@@ -135,6 +137,7 @@ manipulating this list), the user code must observe the following 
protocol on 'lock entry' insertion and removal:



On insertion:



 1) set the 'list_op_pending' word to the address of the 'lock entry'

    to be inserted,

 2) acquire the futex lock,
@@ -143,6 +146,7 @@ On insertion: 
 4) clear the 'list_op_pending' word.



On removal:



 1) set the 'list_op_pending' word to the address of the 'lock entry'

    to be removed,

 2) remove the lock entry for this lock from the 'head' list,