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io_uring: clean poll ->private flagging

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We store a req pointer in wqe->private but also take one bit to mark
double poll entries. Replace macro helpers with inline functions for
better type checking and also name the double flag.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/9a61240555c64ac0b7a9b0eb59a9efeb638a35a4.1655990418.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Pavel Begunkov 2022-06-23 14:24:44 +01:00 committed by Jens Axboe
parent 78a861b949
commit 0638cd7be2
1 changed files with 17 additions and 3 deletions
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20
io_uring/poll.c
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@ -39,6 +39,22 @@ struct io_poll_table {
#define IO_POLL_CANCEL_FLAG BIT(31)
#define IO_POLL_REF_MASK GENMASK(30, 0)
#define IO_WQE_F_DOUBLE 1
static inline struct io_kiocb *wqe_to_req(struct wait_queue_entry *wqe)
{
unsigned long priv = (unsigned long)wqe->private;
return (struct io_kiocb *)(priv & ~IO_WQE_F_DOUBLE);
}
static inline bool wqe_is_double(struct wait_queue_entry *wqe)
{
unsigned long priv = (unsigned long)wqe->private;
return priv & IO_WQE_F_DOUBLE;
}
/*
* If refs part of ->poll_refs (see IO_POLL_REF_MASK) is 0, it's free. We can
* bump it and acquire ownership. It's disallowed to modify requests while not
@ -306,8 +322,6 @@ static void io_poll_cancel_req(struct io_kiocb *req)
io_poll_execute(req, 0, 0);
}
#define wqe_to_req(wait) ((void *)((unsigned long) (wait)->private & ~1))
#define wqe_is_double(wait) ((unsigned long) (wait)->private & 1)
#define IO_ASYNC_POLL_COMMON (EPOLLONESHOT | EPOLLPRI)
static int io_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
@ -392,7 +406,7 @@ static void __io_queue_proc(struct io_poll *poll, struct io_poll_table *pt,
return;
}
/* mark as double wq entry */
wqe_private |= 1;
wqe_private |= IO_WQE_F_DOUBLE;
req->flags |= REQ_F_DOUBLE_POLL;
io_init_poll_iocb(poll, first->events, first->wait.func);
*poll_ptr = poll;