[PATCH v2 3/4] eventfd: simplify eventfd_signal_mask()

Christian Brauner
2023-11-22T12:49:52Z

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