[PATCH AUTOSEL 4.19 114/158] xsk: Properly terminate assignment in xskq_produce_flush_desc

Sasha Levin
2019-07-15T14:27:05Z

From: Nathan Chancellor <natechancellor@gmail.com>

[ Upstream commit f7019b7b0ad14bde732b8953161994edfc384953 ]

Clang warns:

In file included from net/xdp/xsk_queue.c:10:
net/xdp/xsk_queue.h:292:2: warning: expression result unused
[-Wunused-value]
WRITE_ONCE(q->ring->producer, q->prod_tail);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:284:6: note: expanded from macro 'WRITE_ONCE'
__u.__val; \
~~~ ^~~~~
1 warning generated.

The q->prod_tail assignment has a comma at the end, not a semi-colon.
Fix that so clang no longer warns and everything works as expected.

Fixes: c497176cb2e4 ("xsk: add Rx receive functions and poll support")
Link: https://github.com/ClangBuiltLinux/linux/issues/544
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/xdp/xsk_queue.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/xdp/xsk_queue.h b/net/xdp/xsk_queue.h
index 8a64b150be54..fe96c0d039f2 100644
--- a/net/xdp/xsk_queue.h
+++ b/net/xdp/xsk_queue.h
@@ -239,7 +239,7 @@ static inline void xskq_produce_flush_desc(struct xsk_queue *q)
/* Order producer and data */
smp_wmb();

- q->prod_tail = q->prod_head,
+ q->prod_tail = q->prod_head;
WRITE_ONCE(q->ring->producer, q->prod_tail);
}

--
2.20.1