ipc/sem.c: store which operation blocks in perform_atomic_semop()

Preparation for the next patch:

In the slow-path of perform_atomic_semop(), store a pointer to the
operation that caused the operation to block.

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <davidlohr.bueso@hp.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Manfred Spraul 2014-06-06 14:37:49 -07:00 committed by Linus Torvalds
parent d198cd6d6d
commit ed247b7ca0
1 changed files with 3 additions and 0 deletions

View File

@ -109,6 +109,7 @@ struct sem_queue {
int pid; /* process id of requesting process */
int status; /* completion status of operation */
struct sembuf *sops; /* array of pending operations */
struct sembuf *blocking; /* the operation that blocked */
int nsops; /* number of operations */
int alter; /* does *sops alter the array? */
};
@ -642,6 +643,8 @@ out_of_range:
goto undo;
would_block:
q->blocking = sop;
if (sop->sem_flg & IPC_NOWAIT)
result = -EAGAIN;
else