android_kernel_samsung_msm8976/ipc
Davidlohr Bueso a5daa172ff ipc: document general ipc locking scheme
commit 05603c44a7627793219b0bd9a7b236099dc9cd9d upstream.

As suggested by Andrew, add a generic initial locking scheme used
throughout all sysv ipc mechanisms.  Documenting the ids rwsem, how rcu
can be enough to do the initial checks and when to actually acquire the
kern_ipc_perm.lock spinlock.

I found that adding it to util.c was generic enough.

Signed-off-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-18 07:45:48 -07:00
..
compat.c get rid of union semop in sys_semctl(2) arguments 2013-03-05 15:14:16 -05:00
compat_mq.c
ipc_sysctl.c ipc: add sysctl to specify desired next object id 2013-01-04 16:11:45 -08:00
ipcns_notifier.c
Makefile
mq_sysctl.c mqueue: separate mqueue default value from maximum value 2012-05-31 17:49:31 -07:00
mqueue.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2013-03-28 13:43:46 -07:00
msg.c ipc,msg: drop msg_unlock 2013-10-18 07:45:48 -07:00
msgutil.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-05-01 17:51:54 -07:00
namespace.c ipc: rename ids->rw_mutex 2013-10-18 07:45:47 -07:00
sem.c ipc: rename ids->rw_mutex 2013-10-18 07:45:47 -07:00
shm.c ipc: rename ids->rw_mutex 2013-10-18 07:45:47 -07:00
syscall.c get rid of union semop in sys_semctl(2) arguments 2013-03-05 15:14:16 -05:00
util.c ipc: document general ipc locking scheme 2013-10-18 07:45:48 -07:00
util.h ipc: rename ids->rw_mutex 2013-10-18 07:45:47 -07:00