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From:   Christian Brauner <brauner@kernel.org>
Date:   Wed, 22 Nov 2023 13:48:24 +0100
Subject: [PATCH v2 3/4] eventfd: simplify eventfd_signal_mask()
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Precedence: bulk

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.

Signed-off-by: Christian Brauner <brauner@kernel.org>
---
 fs/eventfd.c            | 7 ++++---
 include/linux/eventfd.h | 5 ++---
 io_uring/io_uring.c     | 4 ++--
 3 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/fs/eventfd.c b/fs/eventfd.c
index dc9e01053235..a9a6de920fb4 100644
--- a/fs/eventfd.c
+++ b/fs/eventfd.c
@@ -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);
 
diff --git a/include/linux/eventfd.h b/include/linux/eventfd.h
index 562089431551..4f8aac7eb62a 100644
--- a/include/linux/eventfd.h
+++ b/include/linux/eventfd.h
@@ -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, unsigned mask)
 {
 	return -ENOSYS;
 }
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index ed254076c723..70170a41eac4 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -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))

-- 
2.42.0