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From:   Daniel Vacek <neelx@redhat.com>
To:     Jesse Brandeburg <jesse.brandeburg@intel.com>,
        Tony Nguyen <anthony.l.nguyen@intel.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Richard Cochran <richardcochran@gmail.com>
Cc:     Daniel Vacek <neelx@redhat.com>, intel-wired-lan@lists.osuosl.org,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH v3] ice/ptp: fix the PTP worker retrying indefinitely if the link went down
Date:   Thu, 19 Jan 2023 21:23:16 +0100
Message-Id: <20230119202317.2741092-1-neelx@redhat.com>
In-Reply-To: <20230117181533.2350335-1-neelx@redhat.com>
References: <20230117181533.2350335-1-neelx@redhat.com>
MIME-Version: 1.0
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When the link goes down the ice_ptp_tx_tstamp() may loop re-trying to
process the packets till the 2 seconds timeout finally drops them.
In such a case it makes sense to just drop them right away.

Signed-off-by: Daniel Vacek <neelx@redhat.com>
---
 drivers/net/ethernet/intel/ice/ice_ptp.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_ptp.c b/drivers/net/ethernet/intel/ice/ice_ptp.c
index d63161d73eb16..3c39ae3ed2426 100644
--- a/drivers/net/ethernet/intel/ice/ice_ptp.c
+++ b/drivers/net/ethernet/intel/ice/ice_ptp.c
@@ -680,6 +680,7 @@ static bool ice_ptp_tx_tstamp(struct ice_ptp_tx *tx)
 	struct ice_pf *pf;
 	struct ice_hw *hw;
 	u64 tstamp_ready;
+	bool link_up;
 	int err;
 	u8 idx;
 
@@ -695,11 +696,14 @@ static bool ice_ptp_tx_tstamp(struct ice_ptp_tx *tx)
 	if (err)
 		return false;
 
+	/* Drop packets if the link went down */
+	link_up = ptp_port->link_up;
+
 	for_each_set_bit(idx, tx->in_use, tx->len) {
 		struct skb_shared_hwtstamps shhwtstamps = {};
 		u8 phy_idx = idx + tx->offset;
 		u64 raw_tstamp = 0, tstamp;
-		bool drop_ts = false;
+		bool drop_ts = !link_up;
 		struct sk_buff *skb;
 
 		/* Drop packets which have waited for more than 2 seconds */
@@ -728,7 +732,7 @@ static bool ice_ptp_tx_tstamp(struct ice_ptp_tx *tx)
 		ice_trace(tx_tstamp_fw_req, tx->tstamps[idx].skb, idx);
 
 		err = ice_read_phy_tstamp(hw, tx->block, phy_idx, &raw_tstamp);
-		if (err)
+		if (err && !drop_ts)
 			continue;
 
 		ice_trace(tx_tstamp_fw_done, tx->tstamps[idx].skb, idx);
-- 
2.39.0