aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorJakub Kicinski <jakub.kicinski@netronome.com>2018-10-02 10:10:14 -0700
committerDavid S. Miller <davem@davemloft.net>2018-10-02 11:47:58 -0700
commitff58e2df62ce29d0552278c290ae494b30fe0c6f (patch)
tree49c6b849d1cab1bd98f5e03b95707b9b210f53ff
parentfe3a83af6a50199bf250fa331e94216912f79395 (diff)
downloadsifive-ff58e2df62ce29d0552278c290ae494b30fe0c6f.tar.gz
nfp: avoid soft lockups under control message storm
When FW floods the driver with control messages try to exit the cmsg processing loop every now and then to avoid soft lockups. Cmsg processing is generally very lightweight so 512 seems like a reasonable budget, which should not be exceeded under normal conditions. Fixes: 77ece8d5f196 ("nfp: add control vNIC datapath") Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Tested-by: Pieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--drivers/net/ethernet/netronome/nfp/nfp_net_common.c17
1 files changed, 12 insertions, 5 deletions
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index 8ed38fd5a8520e..c6d29fdbb880f1 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -2077,14 +2077,17 @@ nfp_ctrl_rx_one(struct nfp_net *nn, struct nfp_net_dp *dp,
return true;
}
-static void nfp_ctrl_rx(struct nfp_net_r_vector *r_vec)
+static bool nfp_ctrl_rx(struct nfp_net_r_vector *r_vec)
{
struct nfp_net_rx_ring *rx_ring = r_vec->rx_ring;
struct nfp_net *nn = r_vec->nfp_net;
struct nfp_net_dp *dp = &nn->dp;
+ unsigned int budget = 512;
- while (nfp_ctrl_rx_one(nn, dp, r_vec, rx_ring))
+ while (nfp_ctrl_rx_one(nn, dp, r_vec, rx_ring) && budget--)
continue;
+
+ return budget;
}
static void nfp_ctrl_poll(unsigned long arg)
@@ -2096,9 +2099,13 @@ static void nfp_ctrl_poll(unsigned long arg)
__nfp_ctrl_tx_queued(r_vec);
spin_unlock_bh(&r_vec->lock);
- nfp_ctrl_rx(r_vec);
-
- nfp_net_irq_unmask(r_vec->nfp_net, r_vec->irq_entry);
+ if (nfp_ctrl_rx(r_vec)) {
+ nfp_net_irq_unmask(r_vec->nfp_net, r_vec->irq_entry);
+ } else {
+ tasklet_schedule(&r_vec->tasklet);
+ nn_dp_warn(&r_vec->nfp_net->dp,
+ "control message budget exceeded!\n");
+ }
}
/* Setup and Configuration