[PATCH 5.10 68/80] net: Use u64_stats_fetch_begin_irq() for stats fetch.

Greg Kroah-Hartman
2022-09-06T13:41:47Z

From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

commit 278d3ba61563ceed3cb248383ced19e14ec7bc1f upstream.

On 32bit-UP u64_stats_fetch_begin() disables only preemption. If the
reader is in preemptible context and the writer side
(u64_stats_update_begin*()) runs in an interrupt context (IRQ or
softirq) then the writer can update the stats during the read operation.
This update remains undetected.

Use u64_stats_fetch_begin_irq() to ensure the stats fetch on 32bit-UP
are not interrupted by a writer. 32bit-SMP remains unaffected by this
change.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Catherine Sullivan <csully@google.com>
Cc: David Awogbemila <awogbemila@google.com>
Cc: Dimitris Michailidis <dmichail@fungible.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Hans Ulli Kroll <ulli.kroll@googlemail.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Jeroen de Borst <jeroendb@google.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Simon Horman <simon.horman@corigine.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-wireless@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: oss-drivers@corigine.com
Cc: stable@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/ethernet/cortina/gemini.c | 24 +++++++++----------
drivers/net/ethernet/google/gve/gve_ethtool.c | 16 ++++++------
drivers/net/ethernet/google/gve/gve_main.c | 12 ++++-----
drivers/net/ethernet/huawei/hinic/hinic_rx.c | 4 +--
drivers/net/ethernet/huawei/hinic/hinic_tx.c | 4 +--
drivers/net/ethernet/netronome/nfp/nfp_net_common.c | 8 +++---
drivers/net/ethernet/netronome/nfp/nfp_net_ethtool.c | 8 +++---
drivers/net/netdevsim/netdev.c | 4 +--
net/mac80211/sta_info.c | 8 +++---
net/mpls/af_mpls.c | 4 +--
10 files changed, 46 insertions(+), 46 deletions(-)

--- a/drivers/net/ethernet/cortina/gemini.c
+++ b/drivers/net/ethernet/cortina/gemini.c
@@ -1920,7 +1920,7 @@ static void gmac_get_stats64(struct net_

/* Racing with RX NAPI */
do {
- start = u64_stats_fetch_begin(&port->rx_stats_syncp);
+ start = u64_stats_fetch_begin_irq(&port->rx_stats_syncp);

stats->rx_packets = port->stats.rx_packets;
stats->rx_bytes = port->stats.rx_bytes;
@@ -1932,11 +1932,11 @@ static void gmac_get_stats64(struct net_
stats->rx_crc_errors = port->stats.rx_crc_errors;
stats->rx_frame_errors = port->stats.rx_frame_errors;

- } while (u64_stats_fetch_retry(&port->rx_stats_syncp, start));
+ } while (u64_stats_fetch_retry_irq(&port->rx_stats_syncp, start));

/* Racing with MIB and TX completion interrupts */
do {
- start = u64_stats_fetch_begin(&port->ir_stats_syncp);
+ start = u64_stats_fetch_begin_irq(&port->ir_stats_syncp);

stats->tx_errors = port->stats.tx_errors;
stats->tx_packets = port->stats.tx_packets;
@@ -1946,15 +1946,15 @@ static void gmac_get_stats64(struct net_
stats->rx_missed_errors = port->stats.rx_missed_errors;
stats->rx_fifo_errors = port->stats.rx_fifo_errors;

- } while (u64_stats_fetch_retry(&port->ir_stats_syncp, start));
+ } while (u64_stats_fetch_retry_irq(&port->ir_stats_syncp, start));

/* Racing with hard_start_xmit */
do {
- start = u64_stats_fetch_begin(&port->tx_stats_syncp);
+ start = u64_stats_fetch_begin_irq(&port->tx_stats_syncp);

stats->tx_dropped = port->stats.tx_dropped;

- } while (u64_stats_fetch_retry(&port->tx_stats_syncp, start));
+ } while (u64_stats_fetch_retry_irq(&port->tx_stats_syncp, start));

stats->rx_dropped += stats->rx_missed_errors;
}
@@ -2032,18 +2032,18 @@ static void gmac_get_ethtool_stats(struc
/* Racing with MIB interrupt */
do {
p = values;
- start = u64_stats_fetch_begin(&port->ir_stats_syncp);
+ start = u64_stats_fetch_begin_irq(&port->ir_stats_syncp);

for (i = 0; i < RX_STATS_NUM; i++)
*p++ = port->hw_stats[i];

- } while (u64_stats_fetch_retry(&port->ir_stats_syncp, start));
+ } while (u64_stats_fetch_retry_irq(&port->ir_stats_syncp, start));
values = p;

/* Racing with RX NAPI */
do {
p = values;
- start = u64_stats_fetch_begin(&port->rx_stats_syncp);
+ start = u64_stats_fetch_begin_irq(&port->rx_stats_syncp);

for (i = 0; i < RX_STATUS_NUM; i++)
*p++ = port->rx_stats[i];
@@ -2051,13 +2051,13 @@ static void gmac_get_ethtool_stats(struc
*p++ = port->rx_csum_stats[i];
*p++ = port->rx_napi_exits;

- } while (u64_stats_fetch_retry(&port->rx_stats_syncp, start));
+ } while (u64_stats_fetch_retry_irq(&port->rx_stats_syncp, start));
values = p;

/* Racing with TX start_xmit */
do {
p = values;
- start = u64_stats_fetch_begin(&port->tx_stats_syncp);
+ start = u64_stats_fetch_begin_irq(&port->tx_stats_syncp);

for (i = 0; i < TX_MAX_FRAGS; i++) {
*values++ = port->tx_frag_stats[i];
@@ -2066,7 +2066,7 @@ static void gmac_get_ethtool_stats(struc
*values++ = port->tx_frags_linearized;
*values++ = port->tx_hw_csummed;

- } while (u64_stats_fetch_retry(&port->tx_stats_syncp, start));
+ } while (u64_stats_fetch_retry_irq(&port->tx_stats_syncp, start));
}

static int gmac_get_ksettings(struct net_device *netdev,
--- a/drivers/net/ethernet/google/gve/gve_ethtool.c
+++ b/drivers/net/ethernet/google/gve/gve_ethtool.c
@@ -172,14 +172,14 @@ gve_get_ethtool_stats(struct net_device
struct gve_rx_ring *rx = &priv->rx[ring];

start =
- u64_stats_fetch_begin(&priv->rx[ring].statss);
+ u64_stats_fetch_begin_irq(&priv->rx[ring].statss);
tmp_rx_pkts = rx->rpackets;
tmp_rx_bytes = rx->rbytes;
tmp_rx_skb_alloc_fail = rx->rx_skb_alloc_fail;
tmp_rx_buf_alloc_fail = rx->rx_buf_alloc_fail;
tmp_rx_desc_err_dropped_pkt =
rx->rx_desc_err_dropped_pkt;
- } while (u64_stats_fetch_retry(&priv->rx[ring].statss,
+ } while (u64_stats_fetch_retry_irq(&priv->rx[ring].statss,
start));
rx_pkts += tmp_rx_pkts;
rx_bytes += tmp_rx_bytes;
@@ -193,10 +193,10 @@ gve_get_ethtool_stats(struct net_device
if (priv->tx) {
do {
start =
- u64_stats_fetch_begin(&priv->tx[ring].statss);
+ u64_stats_fetch_begin_irq(&priv->tx[ring].statss);
tmp_tx_pkts = priv->tx[ring].pkt_done;
tmp_tx_bytes = priv->tx[ring].bytes_done;
- } while (u64_stats_fetch_retry(&priv->tx[ring].statss,
+ } while (u64_stats_fetch_retry_irq(&priv->tx[ring].statss,
start));
tx_pkts += tmp_tx_pkts;
tx_bytes += tmp_tx_bytes;
@@ -254,13 +254,13 @@ gve_get_ethtool_stats(struct net_device
data[i++] = rx->cnt;
do {
start =
- u64_stats_fetch_begin(&priv->rx[ring].statss);
+ u64_stats_fetch_begin_irq(&priv->rx[ring].statss);
tmp_rx_bytes = rx->rbytes;
tmp_rx_skb_alloc_fail = rx->rx_skb_alloc_fail;
tmp_rx_buf_alloc_fail = rx->rx_buf_alloc_fail;
tmp_rx_desc_err_dropped_pkt =
rx->rx_desc_err_dropped_pkt;
- } while (u64_stats_fetch_retry(&priv->rx[ring].statss,
+ } while (u64_stats_fetch_retry_irq(&priv->rx[ring].statss,
start));
data[i++] = tmp_rx_bytes;
/* rx dropped packets */
@@ -313,9 +313,9 @@ gve_get_ethtool_stats(struct net_device
data[i++] = tx->done;
do {
start =
- u64_stats_fetch_begin(&priv->tx[ring].statss);
+ u64_stats_fetch_begin_irq(&priv->tx[ring].statss);
tmp_tx_bytes = tx->bytes_done;
- } while (u64_stats_fetch_retry(&priv->tx[ring].statss,
+ } while (u64_stats_fetch_retry_irq(&priv->tx[ring].statss,
start));
data[i++] = tmp_tx_bytes;
data[i++] = tx->wake_queue;
--- a/drivers/net/ethernet/google/gve/gve_main.c
+++ b/drivers/net/ethernet/google/gve/gve_main.c
@@ -40,10 +40,10 @@ static void gve_get_stats(struct net_dev
for (ring = 0; ring < priv->rx_cfg.num_queues; ring++) {
do {
start =
- u64_stats_fetch_begin(&priv->rx[ring].statss);
+ u64_stats_fetch_begin_irq(&priv->rx[ring].statss);
packets = priv->rx[ring].rpackets;
bytes = priv->rx[ring].rbytes;
- } while (u64_stats_fetch_retry(&priv->rx[ring].statss,
+ } while (u64_stats_fetch_retry_irq(&priv->rx[ring].statss,
start));
s->rx_packets += packets;
s->rx_bytes += bytes;
@@ -53,10 +53,10 @@ static void gve_get_stats(struct net_dev
for (ring = 0; ring < priv->tx_cfg.num_queues; ring++) {
do {
start =
- u64_stats_fetch_begin(&priv->tx[ring].statss);
+ u64_stats_fetch_begin_irq(&priv->tx[ring].statss);
packets = priv->tx[ring].pkt_done;
bytes = priv->tx[ring].bytes_done;
- } while (u64_stats_fetch_retry(&priv->tx[ring].statss,
+ } while (u64_stats_fetch_retry_irq(&priv->tx[ring].statss,
start));
s->tx_packets += packets;
s->tx_bytes += bytes;
@@ -1041,9 +1041,9 @@ void gve_handle_report_stats(struct gve_
if (priv->tx) {
for (idx = 0; idx < priv->tx_cfg.num_queues; idx++) {
do {
- start = u64_stats_fetch_begin(&priv->tx[idx].statss);
+ start = u64_stats_fetch_begin_irq(&priv->tx[idx].statss);
tx_bytes = priv->tx[idx].bytes_done;
- } while (u64_stats_fetch_retry(&priv->tx[idx].statss, start));
+ } while (u64_stats_fetch_retry_irq(&priv->tx[idx].statss, start));
stats[stats_idx++] = (struct stats) {
.stat_name = cpu_to_be32(TX_WAKE_CNT),
.value = cpu_to_be64(priv->tx[idx].wake_queue),
--- a/drivers/net/ethernet/huawei/hinic/hinic_rx.c
+++ b/drivers/net/ethernet/huawei/hinic/hinic_rx.c
@@ -74,14 +74,14 @@ void hinic_rxq_get_stats(struct hinic_rx
unsigned int start;

do {
- start = u64_stats_fetch_begin(&rxq_stats->syncp);
+ start = u64_stats_fetch_begin_irq(&rxq_stats->syncp);
stats->pkts = rxq_stats->pkts;
stats->bytes = rxq_stats->bytes;
stats->errors = rxq_stats->csum_errors +
rxq_stats->other_errors;
stats->csum_errors = rxq_stats->csum_errors;
stats->other_errors = rxq_stats->other_errors;
- } while (u64_stats_fetch_retry(&rxq_stats->syncp, start));
+ } while (u64_stats_fetch_retry_irq(&rxq_stats->syncp, start));
}

/**
--- a/drivers/net/ethernet/huawei/hinic/hinic_tx.c
+++ b/drivers/net/ethernet/huawei/hinic/hinic_tx.c
@@ -98,14 +98,14 @@ void hinic_txq_get_stats(struct hinic_tx
unsigned int start;

do {
- start = u64_stats_fetch_begin(&txq_stats->syncp);
+ start = u64_stats_fetch_begin_irq(&txq_stats->syncp);
stats->pkts = txq_stats->pkts;
stats->bytes = txq_stats->bytes;
stats->tx_busy = txq_stats->tx_busy;
stats->tx_wake = txq_stats->tx_wake;
stats->tx_dropped = txq_stats->tx_dropped;
stats->big_frags_pkts = txq_stats->big_frags_pkts;
- } while (u64_stats_fetch_retry(&txq_stats->syncp, start));
+ } while (u64_stats_fetch_retry_irq(&txq_stats->syncp, start));
}

/**
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -3373,21 +3373,21 @@ static void nfp_net_stat64(struct net_de
unsigned int start;

do {
- start = u64_stats_fetch_begin(&r_vec->rx_sync);
+ start = u64_stats_fetch_begin_irq(&r_vec->rx_sync);
data[0] = r_vec->rx_pkts;
data[1] = r_vec->rx_bytes;
data[2] = r_vec->rx_drops;
- } while (u64_stats_fetch_retry(&r_vec->rx_sync, start));
+ } while (u64_stats_fetch_retry_irq(&r_vec->rx_sync, start));
stats->rx_packets += data[0];
stats->rx_bytes += data[1];
stats->rx_dropped += data[2];

do {
- start = u64_stats_fetch_begin(&r_vec->tx_sync);
+ start = u64_stats_fetch_begin_irq(&r_vec->tx_sync);
data[0] = r_vec->tx_pkts;
data[1] = r_vec->tx_bytes;
data[2] = r_vec->tx_errors;
- } while (u64_stats_fetch_retry(&r_vec->tx_sync, start));
+ } while (u64_stats_fetch_retry_irq(&r_vec->tx_sync, start));
stats->tx_packets += data[0];
stats->tx_bytes += data[1];
stats->tx_errors += data[2];
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_ethtool.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_ethtool.c
@@ -494,7 +494,7 @@ static u64 *nfp_vnic_get_sw_stats(struct
unsigned int start;

do {
- start = u64_stats_fetch_begin(&nn->r_vecs[i].rx_sync);
+ start = u64_stats_fetch_begin_irq(&nn->r_vecs[i].rx_sync);
data[0] = nn->r_vecs[i].rx_pkts;
tmp[0] = nn->r_vecs[i].hw_csum_rx_ok;
tmp[1] = nn->r_vecs[i].hw_csum_rx_inner_ok;
@@ -502,10 +502,10 @@ static u64 *nfp_vnic_get_sw_stats(struct
tmp[3] = nn->r_vecs[i].hw_csum_rx_error;
tmp[4] = nn->r_vecs[i].rx_replace_buf_alloc_fail;
tmp[5] = nn->r_vecs[i].hw_tls_rx;
- } while (u64_stats_fetch_retry(&nn->r_vecs[i].rx_sync, start));
+ } while (u64_stats_fetch_retry_irq(&nn->r_vecs[i].rx_sync, start));

do {
- start = u64_stats_fetch_begin(&nn->r_vecs[i].tx_sync);
+ start = u64_stats_fetch_begin_irq(&nn->r_vecs[i].tx_sync);
data[1] = nn->r_vecs[i].tx_pkts;
data[2] = nn->r_vecs[i].tx_busy;
tmp[6] = nn->r_vecs[i].hw_csum_tx;
@@ -515,7 +515,7 @@ static u64 *nfp_vnic_get_sw_stats(struct
tmp[10] = nn->r_vecs[i].hw_tls_tx;
tmp[11] = nn->r_vecs[i].tls_tx_fallback;
tmp[12] = nn->r_vecs[i].tls_tx_no_fallback;
- } while (u64_stats_fetch_retry(&nn->r_vecs[i].tx_sync, start));
+ } while (u64_stats_fetch_retry_irq(&nn->r_vecs[i].tx_sync, start));

data += NN_RVEC_PER_Q_STATS;

--- a/drivers/net/netdevsim/netdev.c
+++ b/drivers/net/netdevsim/netdev.c
@@ -67,10 +67,10 @@ nsim_get_stats64(struct net_device *dev,
unsigned int start;

do {
- start = u64_stats_fetch_begin(&ns->syncp);
+ start = u64_stats_fetch_begin_irq(&ns->syncp);
stats->tx_bytes = ns->tx_bytes;
stats->tx_packets = ns->tx_packets;
- } while (u64_stats_fetch_retry(&ns->syncp, start));
+ } while (u64_stats_fetch_retry_irq(&ns->syncp, start));
}

static int
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -2175,9 +2175,9 @@ static inline u64 sta_get_tidstats_msdu(
u64 value;

do {
- start = u64_stats_fetch_begin(&rxstats->syncp);
+ start = u64_stats_fetch_begin_irq(&rxstats->syncp);
value = rxstats->msdu[tid];
- } while (u64_stats_fetch_retry(&rxstats->syncp, start));
+ } while (u64_stats_fetch_retry_irq(&rxstats->syncp, start));

return value;
}
@@ -2241,9 +2241,9 @@ static inline u64 sta_get_stats_bytes(st
u64 value;

do {
- start = u64_stats_fetch_begin(&rxstats->syncp);
+ start = u64_stats_fetch_begin_irq(&rxstats->syncp);
value = rxstats->bytes;
- } while (u64_stats_fetch_retry(&rxstats->syncp, start));
+ } while (u64_stats_fetch_retry_irq(&rxstats->syncp, start));

return value;
}
--- a/net/mpls/af_mpls.c
+++ b/net/mpls/af_mpls.c
@@ -1078,9 +1078,9 @@ static void mpls_get_stats(struct mpls_d

p = per_cpu_ptr(mdev->stats, i);
do {
- start = u64_stats_fetch_begin(&p->syncp);
+ start = u64_stats_fetch_begin_irq(&p->syncp);
local = p->stats;
- } while (u64_stats_fetch_retry(&p->syncp, start));
+ } while (u64_stats_fetch_retry_irq(&p->syncp, start));

stats->rx_packets += local.rx_packets;
stats->rx_bytes += local.rx_bytes;