net: ifb: 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 <mmyangfl@gmail.com>
Link: https://patch.msgid.link/20260121082348.2388314-1-mmyangfl@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

diff --git a/drivers/net/ifb.c b/drivers/net/ifb.c
index d3dc0914450a87a491c2f634739b324a96d0a9a0..6da801748189584a169cda9f85157eb9ed3065af 100644 (file)
--- a/drivers/net/ifb.c
+++ b/drivers/net/ifb.c
@@ -39,8 +39,8 @@
 #define TX_Q_LIMIT    32
 
 struct ifb_q_stats {
-       u64 packets;
-       u64 bytes;
+       u64_stats_t packets;
+       u64_stats_t bytes;
        struct u64_stats_sync   sync;
 };
 
@@ -81,8 +81,8 @@ static int ifb_close(struct net_device *dev);
 static void ifb_update_q_stats(struct ifb_q_stats *stats, int len)
 {
        u64_stats_update_begin(&stats->sync);
-       stats->packets++;
-       stats->bytes += len;
+       u64_stats_inc(&stats->packets);
+       u64_stats_add(&stats->bytes, len);
        u64_stats_update_end(&stats->sync);
 }
 
@@ -163,16 +163,16 @@ static void ifb_stats64(struct net_device *dev,
        for (i = 0; i < dev->num_tx_queues; i++,txp++) {
                do {
                        start = u64_stats_fetch_begin(&txp->rx_stats.sync);
-                       packets = txp->rx_stats.packets;
-                       bytes = txp->rx_stats.bytes;
+                       packets = u64_stats_read(&txp->rx_stats.packets);
+                       bytes = u64_stats_read(&txp->rx_stats.bytes);
                } while (u64_stats_fetch_retry(&txp->rx_stats.sync, start));
                stats->rx_packets += packets;
                stats->rx_bytes += bytes;
 
                do {
                        start = u64_stats_fetch_begin(&txp->tx_stats.sync);
-                       packets = txp->tx_stats.packets;
-                       bytes = txp->tx_stats.bytes;
+                       packets = u64_stats_read(&txp->tx_stats.packets);
+                       bytes = u64_stats_read(&txp->tx_stats.bytes);
                } while (u64_stats_fetch_retry(&txp->tx_stats.sync, start));
                stats->tx_packets += packets;
                stats->tx_bytes += bytes;
@@ -248,7 +248,7 @@ static void ifb_fill_stats_data(u64 **data,
                start = u64_stats_fetch_begin(&q_stats->sync);
                for (j = 0; j < IFB_Q_STATS_LEN; j++) {
                        offset = ifb_q_stats_desc[j].offset;
-                       (*data)[j] = *(u64 *)(stats_base + offset);
+                       (*data)[j] = u64_stats_read((u64_stats_t *)(stats_base + offset));
                }
        } while (u64_stats_fetch_retry(&q_stats->sync, start));