Unverified Commit 113348a4 authored by Wen Yang's avatar Wen Yang Committed by Christian Brauner
Browse files

eventfd: use wait_event_interruptible_locked_irq() helper 



wait_event_interruptible_locked_irq was introduced by commit 22c43c81
("wait_event_interruptible_locked() interface"), but older code such as
eventfd_{write,read} still uses the open code implementation.
Inspired by commit 8120a8aa
("fs/timerfd.c: make use of wait_event_interruptible_locked_irq()"), this
patch replaces the open code implementation with a single macro call.

No functional change intended.

Signed-off-by: default avatarWen Yang <wenyang.linux@foxmail.com>
Reviewed-by: default avatarEric Biggers <ebiggers@google.com>
Reviewed-by: default avatarJens Axboe <axboe@kernel.dk>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dylan Yudaken <dylany@fb.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Fu Wei <wefu@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Michal Nazarewicz <m.nazarewicz@samsung.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Message-Id: <tencent_16F9553E8354D950D704214D6EA407315F0A@qq.com>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 983652c6

fs/eventfd.c

+7 −34
Original line number Diff line number Diff line
@@ -228,7 +228,6 @@ static ssize_t eventfd_read(struct kiocb *iocb, struct iov_iter *to) 
	struct file *file = iocb->ki_filp;

	struct eventfd_ctx *ctx = file->private_data;

	__u64 ucnt = 0;

	DECLARE_WAITQUEUE(wait, current);



	if (iov_iter_count(to) < sizeof(ucnt))

		return -EINVAL;
@@ -239,23 +238,11 @@ static ssize_t eventfd_read(struct kiocb *iocb, struct iov_iter *to) 
			spin_unlock_irq(&ctx->wqh.lock);

			return -EAGAIN;

		}

		__add_wait_queue(&ctx->wqh, &wait);

		for (;;) {

			set_current_state(TASK_INTERRUPTIBLE);

			if (ctx->count)

				break;

			if (signal_pending(current)) {

				__remove_wait_queue(&ctx->wqh, &wait);

				__set_current_state(TASK_RUNNING);



		if (wait_event_interruptible_locked_irq(ctx->wqh, ctx->count)) {

			spin_unlock_irq(&ctx->wqh.lock);

			return -ERESTARTSYS;

		}

			spin_unlock_irq(&ctx->wqh.lock);

			schedule();

			spin_lock_irq(&ctx->wqh.lock);

		}

		__remove_wait_queue(&ctx->wqh, &wait);

		__set_current_state(TASK_RUNNING);

	}

	eventfd_ctx_do_read(ctx, &ucnt);

	current->in_eventfd = 1;
@@ -275,7 +262,6 @@ static ssize_t eventfd_write(struct file *file, const char __user *buf, size_t c 
	struct eventfd_ctx *ctx = file->private_data;

	ssize_t res;

	__u64 ucnt;

	DECLARE_WAITQUEUE(wait, current);



	if (count < sizeof(ucnt))

		return -EINVAL;
@@ -288,23 +274,10 @@ static ssize_t eventfd_write(struct file *file, const char __user *buf, size_t c 
	if (ULLONG_MAX - ctx->count > ucnt)

		res = sizeof(ucnt);

	else if (!(file->f_flags & O_NONBLOCK)) {

		__add_wait_queue(&ctx->wqh, &wait);

		for (res = 0;;) {

			set_current_state(TASK_INTERRUPTIBLE);

			if (ULLONG_MAX - ctx->count > ucnt) {

		res = wait_event_interruptible_locked_irq(ctx->wqh,

				ULLONG_MAX - ctx->count > ucnt);

		if (!res)

			res = sizeof(ucnt);

				break;

			}

			if (signal_pending(current)) {

				res = -ERESTARTSYS;

				break;

			}

			spin_unlock_irq(&ctx->wqh.lock);

			schedule();

			spin_lock_irq(&ctx->wqh.lock);

		}

		__remove_wait_queue(&ctx->wqh, &wait);

		__set_current_state(TASK_RUNNING);

	}

	if (likely(res > 0)) {

		ctx->count += ucnt;