The __ice_update_sample and __ice_get_ethtool_stats functions directly
accesses the pkts and bytes counters from the ring stats. A following
change is going to update the fields to be u64_stats_t type, and will need
to be accessed appropriately. This will ensure that the accesses do not
cause load/store tearing.
Add helper functions similar to the ones used for updating the stats
values, and use them. This ensures use of the syncp pointer on 32-bit
architectures. Once the fields are updated to u64_stats_t, it will then
properly avoid tears on all architectures.
Reviewed-by: Aleksandr Loktionov
Signed-off-by: Jacob Keller
---
drivers/net/ethernet/intel/ice/ice_lib.h | 6 +
drivers/net/ethernet/intel/ice/ice_ethtool.c | 26 +---
drivers/net/ethernet/intel/ice/ice_lib.c | 36
drivers/net/ethernet/intel/ice/ice_txrx.c| 29 +++---
4 files changed, 75 insertions(+), 22 deletions(-)
diff --git a/drivers/net/ethernet/intel/ice/ice_lib.h
b/drivers/net/ethernet/intel/ice/ice_lib.h
index 2cb1eb98b9da..49454d98dcfe 100644
--- a/drivers/net/ethernet/intel/ice/ice_lib.h
+++ b/drivers/net/ethernet/intel/ice/ice_lib.h
@@ -92,6 +92,12 @@ void ice_update_tx_ring_stats(struct ice_tx_ring *ring, u64
pkts, u64 bytes);
void ice_update_rx_ring_stats(struct ice_rx_ring *ring, u64 pkts, u64 bytes);
+void ice_fetch_tx_ring_stats(const struct ice_tx_ring *ring,
+u64 *pkts, u64 *bytes);
+
+void ice_fetch_rx_ring_stats(const struct ice_rx_ring *ring,
+u64 *pkts, u64 *bytes);
+
void ice_write_intrl(struct ice_q_vector *q_vector, u8 intrl);
void ice_write_itr(struct ice_ring_container *rc, u16 itr);
void ice_set_q_vector_intrl(struct ice_q_vector *q_vector);
diff --git a/drivers/net/ethernet/intel/ice/ice_ethtool.c
b/drivers/net/ethernet/intel/ice/ice_ethtool.c
index 0bc6f31a2b06..6c93e0e91ef5 100644
--- a/drivers/net/ethernet/intel/ice/ice_ethtool.c
+++ b/drivers/net/ethernet/intel/ice/ice_ethtool.c
@@ -1942,25 +1942,35 @@ __ice_get_ethtool_stats(struct net_device *netdev,
rcu_read_lock();
ice_for_each_alloc_txq(vsi, j) {
+ u64 pkts, bytes;
+
tx_ring = READ_ONCE(vsi->tx_rings[j]);
- if (tx_ring && tx_ring->ring_stats) {
- data[i++] = tx_ring->ring_stats->stats.pkts;
- data[i++] = tx_ring->ring_stats->stats.bytes;
- } else {
+ if (!tx_ring || !tx_ring->ring_stats) {
data[i++] = 0;
data[i++] = 0;
+ continue;
}
+
+ ice_fetch_tx_ring_stats(tx_ring, &pkts, &bytes);
+
+ data[i++] = pkts;
+ data[i++] = bytes;
}
ice_for_each_alloc_rxq(vsi, j) {
+ u64 pkts, bytes;
+
rx_ring = READ_ONCE(vsi->rx_rings[j]);
- if (rx_ring && rx_ring->ring_stats) {
- data[i++] = rx_ring->ring_stats->stats.pkts;
- data[i++] = rx_ring->ring_stats->stats.bytes;
- } else {
+ if (!rx_ring || !rx_ring->ring_stats) {
data[i++] = 0;
data[i++] = 0;
+ continue;
}
+
+ ice_fetch_rx_ring_stats(rx_ring, &pkts, &bytes);
+
+ data[i++] = pkts;
+ data[i++] = bytes;
}
rcu_read_unlock();
diff --git a/drivers/net/ethernet/intel/ice/ice_lib.c
b/drivers/net/ethernet/intel/ice/ice_lib.c
index 85bc18600c17..1e3946a1dd36 100644
--- a/drivers/net/ethernet/intel/ice/ice_lib.c
+++ b/drivers/net/ethernet/intel/ice/ice_lib.c
@@ -3474,6 +3474,42 @@ void ice_update_rx_ring_stats(struct ice_rx_ring
*rx_ring, u64 pkts, u64 bytes)
u64_stats_update_end(&rx_ring->ring_stats->syncp);
}
+/**
+ * ice_fetch_tx_ring_stats - Fetch Tx ring packet and byte counters
+ * @ring: ring to update
+ * @pkts: number of processed packets
+ * @bytes: number of processed bytes
+ */
+void ice_fetch_tx_ring_stats(const struct ice_tx_ring *ring,
+u64 *pkts, u64 *bytes)
+{
+ unsigned int start;
+
+ do {
+ start = u64_stats_fetch_begin(&ring->ring_stats->syncp);
+ *pkts = ring->ring_stats->pkts;
+ *bytes = ring->ring_stats->bytes;
+ } while (u64_stats_fetch_retry(&ring->ring_stats->syncp, start));
+}
+
+/**
+ * ice_fetch_rx_ring_stats - Fetch Rx ring packet and byte counters
+ * @ring: ring to read
+ * @pkts: number of processed packets
+ * @bytes: number of processed bytes
+ */
+void ice_fetch_rx_ring_stats(const struct ice_rx_ring *ring,
+u64 *pkts, u64 *bytes)
+{
+ unsigned int start;
+
+ do {
+ start = u64_stats_fetch_begin(&ring->ring_stats->syncp);
+ *pkts = ring->ring_stat
