Commit 9f61eb2d authored by Mohsin Bashir's avatar Mohsin Bashir Committed by Paolo Abeni
Browse files

eth: fbnic: add locking support for hw stats 



This patch adds lock protection for the hardware statistics for fbnic.
The hardware statistics access via ndo_get_stats64 is not protected by
the rtnl_lock(). Since these stats can be accessed from different places
in the code such as service task, ethtool, Q-API, and net_device_ops, a
lock-less approach can lead to races.

Note that this patch is not a fix rather, just a prep for the subsequent
changes in this series.

Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
Signed-off-by: default avatarMohsin Bashir <mohsin.bashr@gmail.com>
Reviewed-by: default avatarSimon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250410070859.4160768-2-mohsin.bashr@gmail.com


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent 24e31e47

drivers/net/ethernet/meta/fbnic/fbnic.h

+3 −0
Original line number Diff line number Diff line
@@ -81,6 +81,9 @@ struct fbnic_dev { 


	/* Local copy of hardware statistics */

	struct fbnic_hw_stats hw_stats;



	/* Lock protecting access to hw_stats */

	spinlock_t hw_stats_lock;

};



/* Reserve entry 0 in the MSI-X "others" array until we have filled all

drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.c

+13 −3
Original line number Diff line number Diff line
@@ -203,18 +203,28 @@ static void fbnic_get_pcie_stats_asic64(struct fbnic_dev *fbd, 


void fbnic_reset_hw_stats(struct fbnic_dev *fbd)

{

	spin_lock(&fbd->hw_stats_lock);

	fbnic_reset_rpc_stats(fbd, &fbd->hw_stats.rpc);

	fbnic_reset_pcie_stats_asic(fbd, &fbd->hw_stats.pcie);

	spin_unlock(&fbd->hw_stats_lock);

}



void fbnic_get_hw_stats32(struct fbnic_dev *fbd)

static void __fbnic_get_hw_stats32(struct fbnic_dev *fbd)

{

	fbnic_get_rpc_stats32(fbd, &fbd->hw_stats.rpc);

}



void fbnic_get_hw_stats(struct fbnic_dev *fbd)

void fbnic_get_hw_stats32(struct fbnic_dev *fbd)

{

	fbnic_get_hw_stats32(fbd);

	spin_lock(&fbd->hw_stats_lock);

	__fbnic_get_hw_stats32(fbd);

	spin_unlock(&fbd->hw_stats_lock);

}



void fbnic_get_hw_stats(struct fbnic_dev *fbd)

{

	spin_lock(&fbd->hw_stats_lock);

	__fbnic_get_hw_stats32(fbd);

	fbnic_get_pcie_stats_asic64(fbd, &fbd->hw_stats.pcie);

	spin_unlock(&fbd->hw_stats_lock);

}

drivers/net/ethernet/meta/fbnic/fbnic_pci.c

+1 −0
Original line number Diff line number Diff line
@@ -292,6 +292,7 @@ static int fbnic_probe(struct pci_dev *pdev, const struct pci_device_id *ent) 


	fbnic_devlink_register(fbd);

	fbnic_dbg_fbd_init(fbd);

	spin_lock_init(&fbd->hw_stats_lock);



	/* Capture snapshot of hardware stats so netdev can calculate delta */

	fbnic_reset_hw_stats(fbd);