From 9c40d587113688ee8857a011c04714518b01d346 Mon Sep 17 00:00:00 2001
From: Edward Cree <ecree@solarflare.com>
Date: Tue, 29 Sep 2020 22:25:24 +0200
Subject: [PATCH 2/7] net: sfc: Replace in_interrupt() usage
References: git-fixes
Patch-mainline: v5.10-rc1
Git-commit: 623b9988bfd146a438e55816dbfdf8f9a5290dd5
efx_ef10_try_update_nic_stats_vf() used in_interrupt() to figure out
whether it is safe to sleep (for MCDI) or not.
The only caller from which it was not is efx_net_stats(), which can be
invoked under dev_base_lock from net-sysfs::netstat_show().
So add a new update_stats_atomic() method to struct efx_nic_type, and call
it from efx_net_stats(), removing the need for
efx_ef10_try_update_nic_stats_vf() to behave differently for this case
(which it wasn't doing correctly anyway).
For all nic_types other than EF10 VF, this method is NULL so the the
regular update_stats() methods are invoked , which are happy with being
called from atomic contexts.
Fixes: f00bf2305cab ("sfc: don't update stats on VF when called in atomic context")
Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Martin Habets <mhabets@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Denis Kirjanov <denis.kirjanov@suse.com>
---
drivers/net/ethernet/sfc/ef10.c | 22 +++++++++++++---------
drivers/net/ethernet/sfc/efx_common.c | 2 +-
drivers/net/ethernet/sfc/net_driver.h | 5 +++++
drivers/net/ethernet/sfc/nic_common.h | 7 +++++++
4 files changed, 26 insertions(+), 10 deletions(-)
diff --git a/drivers/net/ethernet/sfc/ef10.c b/drivers/net/ethernet/sfc/ef10.c
index e385f5fe8986..82e55c93f89a 100644
--- a/drivers/net/ethernet/sfc/ef10.c
+++ b/drivers/net/ethernet/sfc/ef10.c
@@ -1851,15 +1851,6 @@ static int efx_ef10_try_update_nic_stats_vf(struct efx_nic *efx)
spin_unlock_bh(&efx->stats_lock);
- if (in_interrupt()) {
- /* If in atomic context, cannot update stats. Just update the
- * software stats and return so the caller can continue.
- */
- spin_lock_bh(&efx->stats_lock);
- efx_update_sw_stats(efx, stats);
- return 0;
- }
-
efx_ef10_get_stat_mask(efx, mask);
rc = efx_nic_alloc_buffer(efx, &stats_buf, dma_len, GFP_ATOMIC);
@@ -1918,6 +1909,18 @@ static size_t efx_ef10_update_stats_vf(struct efx_nic *efx, u64 *full_stats,
return efx_ef10_update_stats_common(efx, full_stats, core_stats);
}
+static size_t efx_ef10_update_stats_atomic_vf(struct efx_nic *efx, u64 *full_stats,
+ struct rtnl_link_stats64 *core_stats)
+{
+ struct efx_ef10_nic_data *nic_data = efx->nic_data;
+
+ /* In atomic context, cannot update HW stats. Just update the
+ * software stats and return so the caller can continue.
+ */
+ efx_update_sw_stats(efx, nic_data->stats);
+ return efx_ef10_update_stats_common(efx, full_stats, core_stats);
+}
+
static void efx_ef10_push_irq_moderation(struct efx_channel *channel)
{
struct efx_nic *efx = channel->efx;
@@ -3952,6 +3955,7 @@ const struct efx_nic_type efx_hunt_a0_vf_nic_type = {
.finish_flr = efx_port_dummy_op_void,
.describe_stats = efx_ef10_describe_stats,
.update_stats = efx_ef10_update_stats_vf,
+ .update_stats_atomic = efx_ef10_update_stats_atomic_vf,
.start_stats = efx_port_dummy_op_void,
.pull_stats = efx_port_dummy_op_void,
.stop_stats = efx_port_dummy_op_void,
diff --git a/drivers/net/ethernet/sfc/efx_common.c b/drivers/net/ethernet/sfc/efx_common.c
index 3fc8a294c91c..7b3bd3426116 100644
--- a/drivers/net/ethernet/sfc/efx_common.c
+++ b/drivers/net/ethernet/sfc/efx_common.c
@@ -600,7 +600,7 @@ void efx_net_stats(struct net_device *net_dev, struct rtnl_link_stats64 *stats)
struct efx_nic *efx = netdev_priv(net_dev);
spin_lock_bh(&efx->stats_lock);
- efx->type->update_stats(efx, NULL, stats);
+ efx_nic_update_stats_atomic(efx, NULL, stats);
spin_unlock_bh(&efx->stats_lock);
}
diff --git a/drivers/net/ethernet/sfc/net_driver.h b/drivers/net/ethernet/sfc/net_driver.h
index 062462a13847..275cd8f7bdbf 100644
--- a/drivers/net/ethernet/sfc/net_driver.h
+++ b/drivers/net/ethernet/sfc/net_driver.h
@@ -1214,6 +1214,9 @@ struct efx_udp_tunnel {
* @describe_stats: Describe statistics for ethtool
* @update_stats: Update statistics not provided by event handling.
* Either argument may be %NULL.
+ * @update_stats_atomic: Update statistics while in atomic context, if that
+ * is more limiting than @update_stats. Otherwise, leave %NULL and
+ * driver core will call @update_stats.
* @start_stats: Start the regular fetching of statistics
* @pull_stats: Pull stats from the NIC and wait until they arrive.
* @stop_stats: Stop the regular fetching of statistics
@@ -1359,6 +1362,8 @@ struct efx_nic_type {
size_t (*describe_stats)(struct efx_nic *efx, u8 *names);
size_t (*update_stats)(struct efx_nic *efx, u64 *full_stats,
struct rtnl_link_stats64 *core_stats);
+ size_t (*update_stats_atomic)(struct efx_nic *efx, u64 *full_stats,
+ struct rtnl_link_stats64 *core_stats);
void (*start_stats)(struct efx_nic *efx);
void (*pull_stats)(struct efx_nic *efx);
void (*stop_stats)(struct efx_nic *efx);
diff --git a/drivers/net/ethernet/sfc/nic_common.h b/drivers/net/ethernet/sfc/nic_common.h
index 974107354087..809803cea354 100644
--- a/drivers/net/ethernet/sfc/nic_common.h
+++ b/drivers/net/ethernet/sfc/nic_common.h
@@ -280,6 +280,13 @@ void efx_nic_update_stats(const struct efx_hw_stat_desc *desc, size_t count,
const unsigned long *mask, u64 *stats,
const void *dma_buf, bool accumulate);
void efx_nic_fix_nodesc_drop_stat(struct efx_nic *efx, u64 *stat);
+static inline size_t efx_nic_update_stats_atomic(struct efx_nic *efx, u64 *full_stats,
+ struct rtnl_link_stats64 *core_stats)
+{
+ if (efx->type->update_stats_atomic)
+ return efx->type->update_stats_atomic(efx, full_stats, core_stats);
+ return efx->type->update_stats(efx, full_stats, core_stats);
+}
#define EFX_MAX_FLUSH_TIME 5000
--
2.16.4