[PATCH 2/4] io_uring: convert to using atomic-ref

[Jens Axboe]

Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
 fs/io_uring.c | 18 +++++-------------
 1 file changed, 5 insertions(+), 13 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 59fd8b785262..2ce076fd85dc 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -81,6 +81,7 @@
 #include <linux/tracehook.h>
 #include <linux/audit.h>
 #include <linux/security.h>
+#include <linux/atomic-ref.h>
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/io_uring.h>
@@ -1170,17 +1171,10 @@ static inline void io_tw_lock(struct io_ring_ctx *ctx, bool *locked)
 #define io_for_each_link(pos, head) \
 	for (pos = (head); pos; pos = pos->link)
 
-/*
- * Shamelessly stolen from the mm implementation of page reference checking,
- * see commit f958d7b528b1 for details.
- */
-#define req_ref_zero_or_close_to_overflow(req)	\
-	((unsigned int) atomic_read(&(req->refs)) + 127u <= 127u)
-
 static inline bool req_ref_inc_not_zero(struct io_kiocb *req)
 {
 	WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT));
-	return atomic_inc_not_zero(&req->refs);
+	return atomic_ref_inc_not_zero(&req->refs);
 }
 
 static inline bool req_ref_put_and_test(struct io_kiocb *req)
@@ -1188,21 +1182,19 @@ static inline bool req_ref_put_and_test(struct io_kiocb *req)
 	if (likely(!(req->flags & REQ_F_REFCOUNT)))
 		return true;
 
-	WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
-	return atomic_dec_and_test(&req->refs);
+	return atomic_ref_put_and_test(&req->refs);
 }
 
 static inline void req_ref_put(struct io_kiocb *req)
 {
 	WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT));
-	WARN_ON_ONCE(req_ref_put_and_test(req));
+	atomic_ref_put(&req->refs);
 }
 
 static inline void req_ref_get(struct io_kiocb *req)
 {
 	WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT));
-	WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
-	atomic_inc(&req->refs);
+	atomic_ref_get(&req->refs);
 }
 
 static inline void io_submit_flush_completions(struct io_ring_ctx *ctx)
-- 
2.34.1


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