[PATCH net 3/4] net: hns3: fix one incorrect value of page pool info when queried by debugfs
From: Guangbin Huang <hidden>
Date: 2021-11-26 12:10:08
Also in:
lkml
Subsystem:
hisilicon network subsystem 3 driver (hns3), hisilicon network subsystem driver, networking drivers, the rest · Maintainers:
Jian Shen, Jijie Shao, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Hao Chen <redacted>
Currently, when user queries page pool info by debugfs command
"cat page_pool_info", the cnt of allocated page for page pool may be
incorrect because of memory inconsistency problem caused by compiler
optimization.
So this patch uses READ_ONCE() to read value of pages_state_hold_cnt to
fix this problem.
Fixes: 850bfb912a6d ("net: hns3: debugfs add support dumping page pool info")
Signed-off-by: Hao Chen <redacted>
Signed-off-by: Guangbin Huang <redacted>
---
drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c b/drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c
index fbb8a5f08222..081295bff765 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c@@ -1081,7 +1081,8 @@ static void hns3_dump_page_pool_info(struct hns3_enet_ring *ring, u32 j = 0; sprintf(result[j++], "%u", index); - sprintf(result[j++], "%u", ring->page_pool->pages_state_hold_cnt); + sprintf(result[j++], "%u", + READ_ONCE(ring->page_pool->pages_state_hold_cnt)); sprintf(result[j++], "%u", atomic_read(&ring->page_pool->pages_state_release_cnt)); sprintf(result[j++], "%u", ring->page_pool->p.pool_size);
--
2.33.0