ipc/mqueue.c: remove duplicated code
pipelined_send() and pipelined_receive() are identical, so merge them. [manfred@colorfullife.com: add changelog] Link: http://lkml.kernel.org/r/20191020123305.14715-3-manfred@colorfullife.com Signed-off-by: Davidlohr Bueso <dave@stgolabs.net> Signed-off-by: Manfred Spraul <manfred@colorfullife.com> Cc: <1vier1@web.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Waiman Long <longman@redhat.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
parent
39323c64b8
commit
ed29f17151
33
ipc/mqueue.c
33
ipc/mqueue.c
@ -918,6 +918,23 @@ out_name:
|
|||||||
* The same algorithm is used for senders.
|
* The same algorithm is used for senders.
|
||||||
*/
|
*/
|
||||||
|
|
||||||
|
static inline void __pipelined_op(struct wake_q_head *wake_q,
|
||||||
|
struct mqueue_inode_info *info,
|
||||||
|
struct ext_wait_queue *this)
|
||||||
|
{
|
||||||
|
list_del(&this->list);
|
||||||
|
wake_q_add(wake_q, this->task);
|
||||||
|
/*
|
||||||
|
* Rely on the implicit cmpxchg barrier from wake_q_add such
|
||||||
|
* that we can ensure that updating receiver->state is the last
|
||||||
|
* write operation: As once set, the receiver can continue,
|
||||||
|
* and if we don't have the reference count from the wake_q,
|
||||||
|
* yet, at that point we can later have a use-after-free
|
||||||
|
* condition and bogus wakeup.
|
||||||
|
*/
|
||||||
|
this->state = STATE_READY;
|
||||||
|
}
|
||||||
|
|
||||||
/* pipelined_send() - send a message directly to the task waiting in
|
/* pipelined_send() - send a message directly to the task waiting in
|
||||||
* sys_mq_timedreceive() (without inserting message into a queue).
|
* sys_mq_timedreceive() (without inserting message into a queue).
|
||||||
*/
|
*/
|
||||||
@ -927,17 +944,7 @@ static inline void pipelined_send(struct wake_q_head *wake_q,
|
|||||||
struct ext_wait_queue *receiver)
|
struct ext_wait_queue *receiver)
|
||||||
{
|
{
|
||||||
receiver->msg = message;
|
receiver->msg = message;
|
||||||
list_del(&receiver->list);
|
__pipelined_op(wake_q, info, receiver);
|
||||||
wake_q_add(wake_q, receiver->task);
|
|
||||||
/*
|
|
||||||
* Rely on the implicit cmpxchg barrier from wake_q_add such
|
|
||||||
* that we can ensure that updating receiver->state is the last
|
|
||||||
* write operation: As once set, the receiver can continue,
|
|
||||||
* and if we don't have the reference count from the wake_q,
|
|
||||||
* yet, at that point we can later have a use-after-free
|
|
||||||
* condition and bogus wakeup.
|
|
||||||
*/
|
|
||||||
receiver->state = STATE_READY;
|
|
||||||
}
|
}
|
||||||
|
|
||||||
/* pipelined_receive() - if there is task waiting in sys_mq_timedsend()
|
/* pipelined_receive() - if there is task waiting in sys_mq_timedsend()
|
||||||
@ -955,9 +962,7 @@ static inline void pipelined_receive(struct wake_q_head *wake_q,
|
|||||||
if (msg_insert(sender->msg, info))
|
if (msg_insert(sender->msg, info))
|
||||||
return;
|
return;
|
||||||
|
|
||||||
list_del(&sender->list);
|
__pipelined_op(wake_q, info, sender);
|
||||||
wake_q_add(wake_q, sender->task);
|
|
||||||
sender->state = STATE_READY;
|
|
||||||
}
|
}
|
||||||
|
|
||||||
static int do_mq_timedsend(mqd_t mqdes, const char __user *u_msg_ptr,
|
static int do_mq_timedsend(mqd_t mqdes, const char __user *u_msg_ptr,
|
||||||
|
Loading…
x
Reference in New Issue
Block a user