+++ /dev/null
-From 900bbaae67e980945dec74d36f8afe0de7556d5a Mon Sep 17 00:00:00 2001
-From: Xuewen Yan <xuewen.yan@unisoc.com>
-Date: Fri, 26 Apr 2024 16:05:48 +0800
-Subject: epoll: Add synchronous wakeup support for ep_poll_callback
-
-From: Xuewen Yan <xuewen.yan@unisoc.com>
-
-commit 900bbaae67e980945dec74d36f8afe0de7556d5a upstream.
-
-Now, the epoll only use wake_up() interface to wake up task.
-However, sometimes, there are epoll users which want to use
-the synchronous wakeup flag to hint the scheduler, such as
-Android binder driver.
-So add a wake_up_sync() define, and use the wake_up_sync()
-when the sync is true in ep_poll_callback().
-
-Co-developed-by: Jing Xia <jing.xia@unisoc.com>
-Signed-off-by: Jing Xia <jing.xia@unisoc.com>
-Signed-off-by: Xuewen Yan <xuewen.yan@unisoc.com>
-Link: https://lore.kernel.org/r/20240426080548.8203-1-xuewen.yan@unisoc.com
-Tested-by: Brian Geffon <bgeffon@google.com>
-Reviewed-by: Brian Geffon <bgeffon@google.com>
-Reported-by: Benoit Lize <lizeb@google.com>
-Signed-off-by: Christian Brauner <brauner@kernel.org>
-Cc: Brian Geffon <bgeffon@google.com>
-Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
----
- fs/eventpoll.c | 5 ++++-
- include/linux/wait.h | 1 +
- 2 files changed, 5 insertions(+), 1 deletion(-)
-
---- a/fs/eventpoll.c
-+++ b/fs/eventpoll.c
-@@ -1273,7 +1273,10 @@ static int ep_poll_callback(wait_queue_e
- break;
- }
- }
-- wake_up(&ep->wq);
-+ if (sync)
-+ wake_up_sync(&ep->wq);
-+ else
-+ wake_up(&ep->wq);
- }
- if (waitqueue_active(&ep->poll_wait))
- pwake++;
---- a/include/linux/wait.h
-+++ b/include/linux/wait.h
-@@ -213,6 +213,7 @@ void __wake_up_pollfree(struct wait_queu
- #define wake_up_all(x) __wake_up(x, TASK_NORMAL, 0, NULL)
- #define wake_up_locked(x) __wake_up_locked((x), TASK_NORMAL, 1)
- #define wake_up_all_locked(x) __wake_up_locked((x), TASK_NORMAL, 0)
-+#define wake_up_sync(x) __wake_up_sync(x, TASK_NORMAL)
-
- #define wake_up_interruptible(x) __wake_up(x, TASK_INTERRUPTIBLE, 1, NULL)
- #define wake_up_interruptible_nr(x, nr) __wake_up(x, TASK_INTERRUPTIBLE, nr, NULL)