Commit 120ae585 authored by Christian Brauner's avatar Christian Brauner
Browse files

eventfd: simplify eventfd_signal_mask() 

The eventfd_signal_mask() helper was introduced for io_uring and similar
to eventfd_signal() it always passed 1 for @n. So don't bother with that
argument at all.

Link: https://lore.kernel.org/r/20231122-vfs-eventfd-signal-v2-3-bd549b14ce0c@kernel.org


Reviewed-by: default avatarJan Kara <jack@suse.cz>
Reviewed-by: default avatarJens Axboe <axboe@kernel.dk>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 3652117f

fs/eventfd.c

+4 −3
Original line number Diff line number Diff line
@@ -43,9 +43,10 @@ struct eventfd_ctx { 
	int id;

};



__u64 eventfd_signal_mask(struct eventfd_ctx *ctx, __u64 n, __poll_t mask)

__u64 eventfd_signal_mask(struct eventfd_ctx *ctx, __poll_t mask)

{

	unsigned long flags;

	__u64 n = 1;



	/*

	 * Deadlock or stack overflow issues can happen if we recurse here
@@ -68,7 +69,7 @@ __u64 eventfd_signal_mask(struct eventfd_ctx *ctx, __u64 n, __poll_t mask) 
	current->in_eventfd = 0;

	spin_unlock_irqrestore(&ctx->wqh.lock, flags);



	return n;

	return n == 1;

}



/**
@@ -84,7 +85,7 @@ __u64 eventfd_signal_mask(struct eventfd_ctx *ctx, __u64 n, __poll_t mask) 
 */

__u64 eventfd_signal(struct eventfd_ctx *ctx)

{

	return eventfd_signal_mask(ctx, 1, 0);

	return eventfd_signal_mask(ctx, 0);

}

EXPORT_SYMBOL_GPL(eventfd_signal);

include/linux/eventfd.h

+2 −3
Original line number Diff line number Diff line
@@ -36,7 +36,7 @@ struct file *eventfd_fget(int fd); 
struct eventfd_ctx *eventfd_ctx_fdget(int fd);

struct eventfd_ctx *eventfd_ctx_fileget(struct file *file);

__u64 eventfd_signal(struct eventfd_ctx *ctx);

__u64 eventfd_signal_mask(struct eventfd_ctx *ctx, __u64 n, __poll_t mask);

__u64 eventfd_signal_mask(struct eventfd_ctx *ctx, __poll_t mask);

int eventfd_ctx_remove_wait_queue(struct eventfd_ctx *ctx, wait_queue_entry_t *wait,

				  __u64 *cnt);

void eventfd_ctx_do_read(struct eventfd_ctx *ctx, __u64 *cnt);
@@ -63,8 +63,7 @@ static inline int eventfd_signal(struct eventfd_ctx *ctx) 
	return -ENOSYS;

}



static inline int eventfd_signal_mask(struct eventfd_ctx *ctx, __u64 n,

				      unsigned mask)

static inline int eventfd_signal_mask(struct eventfd_ctx *ctx, __poll_t mask)

{

	return -ENOSYS;

}

io_uring/io_uring.c

+2 −2
Original line number Diff line number Diff line
@@ -558,7 +558,7 @@ static void io_eventfd_ops(struct rcu_head *rcu) 
	int ops = atomic_xchg(&ev_fd->ops, 0);



	if (ops & BIT(IO_EVENTFD_OP_SIGNAL_BIT))

		eventfd_signal_mask(ev_fd->cq_ev_fd, 1, EPOLL_URING_WAKE);

		eventfd_signal_mask(ev_fd->cq_ev_fd, EPOLL_URING_WAKE);



	/* IO_EVENTFD_OP_FREE_BIT may not be set here depending on callback

	 * ordering in a race but if references are 0 we know we have to free
@@ -594,7 +594,7 @@ static void io_eventfd_signal(struct io_ring_ctx *ctx) 
		goto out;



	if (likely(eventfd_signal_allowed())) {

		eventfd_signal_mask(ev_fd->cq_ev_fd, 1, EPOLL_URING_WAKE);

		eventfd_signal_mask(ev_fd->cq_ev_fd, EPOLL_URING_WAKE);

	} else {

		atomic_inc(&ev_fd->refs);

		if (!atomic_fetch_or(BIT(IO_EVENTFD_OP_SIGNAL_BIT), &ev_fd->ops))