[PATCH 4.19 022/105] net/mlx5: Fix FW tracer timestamp calculation

Greg Kroah-Hartman
2022-12-05T19:18:41Z

From: Moshe Shemesh <moshe@nvidia.com>

[ Upstream commit 61db3d7b99a367416e489ccf764cc5f9b00d62a1 ]

Fix a bug in calculation of FW tracer timestamp. Decreasing one in the
calculation should effect only bits 52_7 and not effect bits 6_0 of the
timestamp, otherwise bits 6_0 are always set in this calculation.

Fixes: 70dd6fdb8987 ("net/mlx5: FW tracer, parse traces and kernel tracing support")
Signed-off-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Feras Daoud <ferasda@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c b/drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c
index a22e932a00b0..ef9f932f0226 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c
@@ -600,7 +600,7 @@ static void mlx5_tracer_handle_timestamp_trace(struct mlx5_fw_tracer *tracer,
trace_timestamp = (timestamp_event.timestamp & MASK_52_7) |
(str_frmt->timestamp & MASK_6_0);
else
- trace_timestamp = ((timestamp_event.timestamp & MASK_52_7) - 1) |
+ trace_timestamp = ((timestamp_event.timestamp - 1) & MASK_52_7) |
(str_frmt->timestamp & MASK_6_0);

mlx5_tracer_print_trace(str_frmt, dev, trace_timestamp);
--
2.35.1