Commit 623b9988 authored by Edward Cree's avatar Edward Cree Committed by David S. Miller
Browse files

net: sfc: Replace in_interrupt() usage 



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: f00bf230 ("sfc: don't update stats on VF when called in atomic context")
Reported-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: default avatarEdward Cree <ecree@solarflare.com>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Reviewed-by: default avatarMartin Habets <mhabets@solarflare.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 606dbf8d

drivers/net/ethernet/sfc/ef10.c

+13 −9
Original line number Diff line number Diff line
@@ -1871,15 +1871,6 @@ 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);
@@ -1938,6 +1929,18 @@ 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;
@@ -3998,6 +4001,7 @@ 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,

drivers/net/ethernet/sfc/efx_common.c

+1 −1
Original line number Diff line number Diff line
@@ -602,7 +602,7 @@ 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);

}

drivers/net/ethernet/sfc/net_driver.h

+5 −0
Original line number Diff line number Diff line
@@ -1172,6 +1172,9 @@ 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
@@ -1316,6 +1319,8 @@ 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);

drivers/net/ethernet/sfc/nic_common.h

+7 −0
Original line number Diff line number Diff line
@@ -244,6 +244,13 @@ 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