[PATCH 5.4 08/34] nfp: flower: fix used time of merge flow statistics

Greg Kroah-Hartman
2020-06-09T17:53:43Z

From: Heinrich Kuhn <heinrich.kuhn@netronome.com>

[ Upstream commit 5b186cd60f033110960a3db424ffbd6de4cee528 ]

Prior to this change the correct value for the used counter is calculated
but not stored nor, therefore, propagated to user-space. In use-cases such
as OVS use-case at least this results in active flows being removed from
the hardware datapath. Which results in both unnecessary flow tear-down
and setup, and packet processing on the host.

This patch addresses the problem by saving the calculated used value
which allows the value to propagate to user-space.

Found by inspection.

Fixes: aa6ce2ea0c93 ("nfp: flower: support stats update for merge flows")
Signed-off-by: Heinrich Kuhn <heinrich.kuhn@netronome.com>
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/ethernet/netronome/nfp/flower/offload.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/netronome/nfp/flower/offload.c
+++ b/drivers/net/ethernet/netronome/nfp/flower/offload.c
@@ -1368,7 +1368,8 @@ __nfp_flower_update_merge_stats(struct n
ctx_id = be32_to_cpu(sub_flow->meta.host_ctx_id);
priv->stats[ctx_id].pkts += pkts;
priv->stats[ctx_id].bytes += bytes;
- max_t(u64, priv->stats[ctx_id].used, used);
+ priv->stats[ctx_id].used = max_t(u64, used,
+ priv->stats[ctx_id].used);
}
}