The application provides timestamps in Tx mbuf as clocks,
the hardware performs scheduling on Clock Queue completion index
match. This patch introduces the timestamp-to-completion-index
inline routine.
Signed-off-by: Viacheslav Ovsiienko <viachesl...@mellanox.com>
Acked-by: Matan Azrad <ma...@mellanox.com>
---
drivers/net/mlx5/mlx5.h | 2 ++
drivers/net/mlx5/mlx5_rxtx.h | 55 ++++++++++++++++++++++++++++++++++++++++++++
drivers/net/mlx5/mlx5_txpp.c | 5 ++++
3 files changed, 62 insertions(+)
diff --git a/drivers/net/mlx5/mlx5.h b/drivers/net/mlx5/mlx5.h
index e599bbb..a61394c 100644
--- a/drivers/net/mlx5/mlx5.h
+++ b/drivers/net/mlx5/mlx5.h
@@ -585,6 +585,8 @@ struct mlx5_dev_txpp {
rte_atomic32_t err_miss_int; /* Missed service interrupt. */
rte_atomic32_t err_rearm_queue; /* Rearm Queue errors. */
rte_atomic32_t err_clock_queue; /* Clock Queue errors. */
+ rte_atomic32_t err_ts_past; /* Timestamp in the past. */
+ rte_atomic32_t err_ts_future; /* Timestamp in the distant future. */
};
/*
diff --git a/drivers/net/mlx5/mlx5_rxtx.h b/drivers/net/mlx5/mlx5_rxtx.h
index 974a847..d082cd7 100644
--- a/drivers/net/mlx5/mlx5_rxtx.h
+++ b/drivers/net/mlx5/mlx5_rxtx.h
@@ -719,4 +719,59 @@ int mlx5_dma_unmap(struct rte_pci_device *pdev, void
*addr, uint64_t iova,
return (ts & UINT32_MAX) + (ts >> 32) * NS_PER_S;
}
+/**
+ * Convert timestamp from mbuf format to linear counter
+ * of Clock Queue completions (24 bits)
+ *
+ * @param sh
+ * Pointer to the device shared context to fetch Tx
+ * packet pacing timestamp and parameters.
+ * @param ts
+ * Timestamp from mbuf to convert.
+ * @return
+ * positive or zero value - completion ID to wait
+ * negative value - conversion error
+ */
+static __rte_always_inline int32_t
+mlx5_txpp_convert_tx_ts(struct mlx5_dev_ctx_shared *sh, uint64_t mts)
+{
+ uint64_t ts, ci;
+ uint32_t tick;
+
+ do {
+ /*
+ * Read atomically two uint64_t fields and compare lsb bits.
+ * It there is no match - the timestamp was updated in
+ * the service thread, data should be re-read.
+ */
+ rte_compiler_barrier();
+ ci = rte_atomic64_read(&sh->txpp.ts.ci_ts);
+ ts = rte_atomic64_read(&sh->txpp.ts.ts);
+ rte_compiler_barrier();
+ if (!((ts ^ ci) << (64 - MLX5_CQ_INDEX_WIDTH)))
+ break;
+ } while (true);
+ /* Perform the skew correction, positive value to send earlier. */
+ mts -= sh->txpp.skew;
+ mts -= ts;
+ if (unlikely(mts >= UINT64_MAX / 2)) {
+ /* We have negative integer, mts is in the past. */
+ rte_atomic32_inc(&sh->txpp.err_ts_past);
+ return -1;
+ }
+ tick = sh->txpp.tick;
+ MLX5_ASSERT(tick);
+ /* Convert delta to completions, round up. */
+ mts = (mts + tick - 1) / tick;
+ if (unlikely(mts >= (1 << MLX5_CQ_INDEX_WIDTH) / 2 - 1)) {
+ /* We have mts is too distant future. */
+ rte_atomic32_inc(&sh->txpp.err_ts_future);
+ return -1;
+ }
+ mts <<= 64 - MLX5_CQ_INDEX_WIDTH;
+ ci += mts;
+ ci >>= 64 - MLX5_CQ_INDEX_WIDTH;
+ return ci;
+}
+
#endif /* RTE_PMD_MLX5_RXTX_H_ */
diff --git a/drivers/net/mlx5/mlx5_txpp.c b/drivers/net/mlx5/mlx5_txpp.c
index 17d64ff..799b20a 100644
--- a/drivers/net/mlx5/mlx5_txpp.c
+++ b/drivers/net/mlx5/mlx5_txpp.c
@@ -858,6 +858,11 @@
int flags;
int ret;
+ rte_atomic32_set(&sh->txpp.err_miss_int, 0);
+ rte_atomic32_set(&sh->txpp.err_rearm_queue, 0);
+ rte_atomic32_set(&sh->txpp.err_clock_queue, 0);
+ rte_atomic32_set(&sh->txpp.err_ts_past, 0);
+ rte_atomic32_set(&sh->txpp.err_ts_future, 0);
/* Attach interrupt handler to process Rearm Queue completions. */
flags = fcntl(sh->txpp.echan->fd, F_GETFL);
ret = fcntl(sh->txpp.echan->fd, F_SETFL, flags | O_NONBLOCK);
--
1.8.3.1
