Implement the deferred tx key deletion api. In the case of mlx5,
mlx5e_psp_tx_grace_begin() records the number of wqes retired on each
tx queue, and then mlx5e_psp_tx_grace_end() returns 0 only if
all tx queues have advanced a full ring cycle past the point where
they were snapshotted.

Signed-off-by: Daniel Zahka <[email protected]>
---
 .../net/ethernet/mellanox/mlx5/core/en_accel/psp.c | 101 +++++++++++++++++++--
 .../net/ethernet/mellanox/mlx5/core/en_accel/psp.h |   7 ++
 drivers/net/ethernet/mellanox/mlx5/core/en_stats.h |   1 +
 drivers/net/ethernet/mellanox/mlx5/core/en_tx.c    |   1 +
 4 files changed, 104 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.c 
b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.c
index 9a74438ce10a..30f1dbc3fa9d 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.c
@@ -1059,13 +1059,102 @@ mlx5e_psp_get_stats(struct psp_dev *psd, struct 
psp_dev_stats *stats)
        stats->tx_error = atomic_read(&priv->psp->tx_drop);
 }
 
+static int mlx5e_psp_tx_grace_begin(struct psp_dev *psd)
+{
+       struct mlx5e_priv *priv = netdev_priv(psd->main_netdev);
+       struct mlx5e_psp_tx_snapshot *snap;
+       int num_channels, num_tc, num_sqs;
+       int idx = 0, rc = 0;
+       int i, tc;
+
+       mutex_lock(&priv->state_lock);
+
+       num_channels = priv->channels.num;
+       num_tc = mlx5e_get_dcb_num_tc(&priv->channels.params);
+       num_sqs = num_channels * num_tc;
+
+       snap = kzalloc(struct_size(snap, wqes, num_sqs), GFP_KERNEL);
+       if (!snap) {
+               rc = -ENOMEM;
+               goto out_unlock;
+       }
+
+       snap->num_channels = num_channels;
+       snap->num_tc = num_tc;
+
+       for (i = 0; i < priv->channels.num; i++) {
+               struct mlx5e_channel *c = priv->channels.c[i];
+
+               for (tc = 0; tc < c->num_tc; tc++)
+                       snap->wqes[idx++] = READ_ONCE(c->sq[tc].stats->wqes);
+       }
+
+       priv->psp->tx_snapshot = snap;
+
+out_unlock:
+       mutex_unlock(&priv->state_lock);
+       return rc;
+}
+
+static int mlx5e_psp_tx_grace_end(struct psp_dev *psd)
+{
+       struct mlx5e_priv *priv = netdev_priv(psd->main_netdev);
+       struct mlx5e_psp_tx_snapshot *snap;
+       int num_channels, num_tc;
+       int idx = 0, rc = 0;
+       int i, tc;
+
+       mutex_lock(&priv->state_lock);
+
+       snap = priv->psp->tx_snapshot;
+       num_channels = priv->channels.num;
+       num_tc = mlx5e_get_dcb_num_tc(&priv->channels.params);
+
+       /* If channels were reconfigured, tell core to restart grace period */
+       if (snap->num_channels != num_channels || snap->num_tc != num_tc) {
+               kfree(snap);
+               priv->psp->tx_snapshot = NULL;
+               rc = -ESTALE;
+               goto out_unlock;
+       }
+
+       for (i = 0; i < priv->channels.num; i++) {
+               struct mlx5e_channel *c = priv->channels.c[i];
+
+               for (tc = 0; tc < c->num_tc; tc++) {
+                       struct mlx5e_txqsq *sq = &c->sq[tc];
+                       u32 ring_size = mlx5_wq_cyc_get_size(&sq->wq);
+                       u64 current_wqes = READ_ONCE(sq->stats->wqes);
+                       u64 snapshot_wqes = snap->wqes[idx++];
+
+                       /* If the ring has cycled, any key_id handles in tx
+                        * descriptors must have been consumed by hw and
+                        * cleaned by sw.
+                        */
+                       if ((s64)(current_wqes - snapshot_wqes) < ring_size) {
+                               rc = -EAGAIN;
+                               goto out_unlock;
+                       }
+               }
+       }
+
+       kfree(snap);
+       priv->psp->tx_snapshot = NULL;
+
+out_unlock:
+       mutex_unlock(&priv->state_lock);
+       return rc;
+}
+
 static struct psp_dev_ops mlx5_psp_ops = {
-       .set_config   = mlx5e_psp_set_config,
-       .rx_spi_alloc = mlx5e_psp_rx_spi_alloc,
-       .tx_key_add   = mlx5e_psp_assoc_add,
-       .tx_key_del   = mlx5e_psp_assoc_del,
-       .key_rotate   = mlx5e_psp_key_rotate,
-       .get_stats    = mlx5e_psp_get_stats,
+       .set_config     = mlx5e_psp_set_config,
+       .rx_spi_alloc   = mlx5e_psp_rx_spi_alloc,
+       .tx_key_add     = mlx5e_psp_assoc_add,
+       .tx_key_del     = mlx5e_psp_assoc_del,
+       .key_rotate     = mlx5e_psp_key_rotate,
+       .tx_grace_begin = mlx5e_psp_tx_grace_begin,
+       .tx_grace_end   = mlx5e_psp_tx_grace_end,
+       .get_stats      = mlx5e_psp_get_stats,
 };
 
 void mlx5e_psp_unregister(struct mlx5e_priv *priv)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.h 
b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.h
index 6b62fef0d9a7..29800050a331 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/psp.h
@@ -22,10 +22,17 @@ struct mlx5e_psp_stats {
        u64 psp_tx_bytes_drop;
 };
 
+struct mlx5e_psp_tx_snapshot {
+       int num_channels;
+       int num_tc;
+       u64 wqes[];
+};
+
 struct mlx5e_psp {
        struct psp_dev *psp;
        struct psp_dev_caps caps;
        struct mlx5e_psp_fs *fs;
+       struct mlx5e_psp_tx_snapshot *tx_snapshot;
        atomic_t tx_key_cnt;
        atomic_t tx_drop;
 };
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_stats.h 
b/drivers/net/ethernet/mellanox/mlx5/core/en_stats.h
index 09f155acb461..5173a0d3f01a 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_stats.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_stats.h
@@ -445,6 +445,7 @@ struct mlx5e_sq_stats {
        u64 cqes ____cacheline_aligned_in_smp;
        u64 wake;
        u64 cqe_err;
+       u64 wqes;
 };
 
 struct mlx5e_xdpsq_stats {
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c 
b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
index a01ee656a1e7..412ebc160056 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
@@ -883,6 +883,7 @@ bool mlx5e_poll_tx_cq(struct mlx5e_cq *cq, int napi_budget)
        wmb();
 
        sq->dma_fifo_cc = dma_fifo_cc;
+       stats->wqes += (u16)(sqcc - sq->cc);
        sq->cc = sqcc;
 
        netdev_tx_completed_queue(sq->txq, npkts, nbytes);

-- 
2.47.3


Reply via email to