From 5c05b3dbccb17ddd6515a6c749feee9b657a5640 Mon Sep 17 00:00:00 2001 From: David Yang Date: Sat, 24 Jan 2026 05:10:55 +0800 Subject: [PATCH] netdevsim: use u64_stats_t with u64_stats_sync properly On 64bit arches, struct u64_stats_sync is empty and provides no help against load/store tearing. Convert to u64_stats_t to ensure atomic operations. Signed-off-by: David Yang Link: https://patch.msgid.link/20260123211101.2929547-1-mmyangfl@gmail.com Signed-off-by: Jakub Kicinski --- drivers/net/netdevsim/netdevsim.h | 8 ++++---- drivers/net/netdevsim/psp.c | 18 ++++++++++-------- 2 files changed, 14 insertions(+), 12 deletions(-) diff --git a/drivers/net/netdevsim/netdevsim.h b/drivers/net/netdevsim/netdevsim.h index 46c67983c5171..f767fc8a75053 100644 --- a/drivers/net/netdevsim/netdevsim.h +++ b/drivers/net/netdevsim/netdevsim.h @@ -109,10 +109,10 @@ struct netdevsim { int rq_reset_mode; struct { - u64 rx_packets; - u64 rx_bytes; - u64 tx_packets; - u64 tx_bytes; + u64_stats_t rx_packets; + u64_stats_t rx_bytes; + u64_stats_t tx_packets; + u64_stats_t tx_bytes; struct u64_stats_sync syncp; struct psp_dev *dev; u32 spi; diff --git a/drivers/net/netdevsim/psp.c b/drivers/net/netdevsim/psp.c index 727da06101caa..0b4d717253b08 100644 --- a/drivers/net/netdevsim/psp.c +++ b/drivers/net/netdevsim/psp.c @@ -72,10 +72,12 @@ nsim_do_psp(struct sk_buff *skb, struct netdevsim *ns, skb->decrypted = 1; u64_stats_update_begin(&ns->psp.syncp); - ns->psp.tx_packets++; - ns->psp.rx_packets++; - ns->psp.tx_bytes += skb->len - skb_inner_transport_offset(skb); - ns->psp.rx_bytes += skb->len - skb_inner_transport_offset(skb); + u64_stats_inc(&ns->psp.tx_packets); + u64_stats_inc(&ns->psp.rx_packets); + u64_stats_add(&ns->psp.tx_bytes, + skb->len - skb_inner_transport_offset(skb)); + u64_stats_add(&ns->psp.rx_bytes, + skb->len - skb_inner_transport_offset(skb)); u64_stats_update_end(&ns->psp.syncp); } else { struct ipv6hdr *ip6h __maybe_unused; @@ -183,10 +185,10 @@ static void nsim_get_stats(struct psp_dev *psd, struct psp_dev_stats *stats) do { start = u64_stats_fetch_begin(&ns->psp.syncp); - stats->rx_bytes = ns->psp.rx_bytes; - stats->rx_packets = ns->psp.rx_packets; - stats->tx_bytes = ns->psp.tx_bytes; - stats->tx_packets = ns->psp.tx_packets; + stats->rx_bytes = u64_stats_read(&ns->psp.rx_bytes); + stats->rx_packets = u64_stats_read(&ns->psp.rx_packets); + stats->tx_bytes = u64_stats_read(&ns->psp.tx_bytes); + stats->tx_packets = u64_stats_read(&ns->psp.tx_packets); } while (u64_stats_fetch_retry(&ns->psp.syncp, start)); } -- 2.47.3