[dpdk-dev] [PATCH 1/5] net/bnx2x: fix packet drop

[Shahed Shaikh]

Patch "8bd31421c593 ("net/bnx2x: fix ramrod timeout")"
introduced a regression where sc->scan_fp flags is
set for unexpectedly long time. So the slow path completion
handler flow is run unnecessarily which walks over receive
descriptor ring of fast path and drops the data packets while looking
for slow path completion descriptor out of fast path ring.

This issue is seen under heavy traffic with link events happening
in background.

Fixes: 8bd31421c593 ("net/bnx2x: fix ramrod timeout")
Cc: stable at dpdk.org

Signed-off-by: Shahed Shaikh <shshaikh at marvell.com>
---
 drivers/net/bnx2x/bnx2x.c    | 2 ++
 drivers/net/bnx2x/ecore_sp.c | 4 ----
 2 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/net/bnx2x/bnx2x.c b/drivers/net/bnx2x/bnx2x.c
index 3e705c7a1..0698b1a8a 100644
--- a/drivers/net/bnx2x/bnx2x.c
+++ b/drivers/net/bnx2x/bnx2x.c
@@ -4572,6 +4572,8 @@ static void bnx2x_handle_fp_tq(struct bnx2x_fastpath *fp)
 		}
 	}
 
+	/* Assuming we have completed slow path completion, clear the flag */
+	rte_atomic32_set(&sc->scan_fp, 0);
 	bnx2x_ack_sb(sc, fp->igu_sb_id, USTORM_ID,
 		   le16toh(fp->fp_hc_idx), IGU_INT_ENABLE, 1);
 }
diff --git a/drivers/net/bnx2x/ecore_sp.c b/drivers/net/bnx2x/ecore_sp.c
index 43194095b..5ac22e725 100644
--- a/drivers/net/bnx2x/ecore_sp.c
+++ b/drivers/net/bnx2x/ecore_sp.c
@@ -291,10 +291,6 @@ static int ecore_state_wait(struct bnx2x_softc *sc, int state,
 		cnt *= 20;
 
 	ECORE_MSG(sc, "waiting for state to become %d", state);
-	/* being over protective to remind bnx2x_intr_legacy() to
-	 * process RAMROD
-	 */
-	rte_atomic32_set(&sc->scan_fp, 1);
 
 	ECORE_MIGHT_SLEEP();
 	while (cnt--) {
-- 
2.12.3