From 69e408a2cfa1ed26cdc2bd10ffa44b3e2b327da9 Mon Sep 17 00:00:00 2001 From: Petr Machata Date: Thu, 17 Sep 2020 09:49:01 +0300 Subject: [PATCH 1/3] mlxsw: spectrum_buffers: Support two headroom modes There are two interfaces to configure ETS: qdiscs and DCB. Historically, DCB ETS configuration was projected to ingress as well, and configured port buffers. Qdisc was not. So as not to break clients that today use DCB ETS and PFC and rely on getting a reasonable ingress buffer priomap, keep the ETS mirroring in effect. Since qdiscs have not done this mirroring historically, it is reasonable not to introduce it, but rather permit manual ingress configuration through dcbnl_setbuffer only in the qdisc mode. This will require a toggle to indicate whether buffer sizes should be autocomputed or taken from dcbnl_setbuffer, and likewise for priomaps. Introduce such and initialize it, and guard port buffer size configuration as appropriate. The toggle is currently left in the DCB position. In a following patch, qdisc code will switch it. Signed-off-by: Petr Machata Reviewed-by: Jiri Pirko Signed-off-by: Ido Schimmel Signed-off-by: David S. Miller --- .../net/ethernet/mellanox/mlxsw/spectrum.h | 11 ++++++++++ .../mellanox/mlxsw/spectrum_buffers.c | 22 ++++++++++++++++--- 2 files changed, 30 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.h b/drivers/net/ethernet/mellanox/mlxsw/spectrum.h index 247a6aebd402..f0a4347acd25 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.h +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.h @@ -434,18 +434,29 @@ struct mlxsw_sp_hdroom_prio { u8 buf_idx; /* Value of buf_idx deduced from the DCB ETS configuration. */ u8 ets_buf_idx; + /* Value of buf_idx taken from the dcbnl_setbuffer configuration. */ + u8 set_buf_idx; bool lossy; }; struct mlxsw_sp_hdroom_buf { u32 thres_cells; u32 size_cells; + /* Size requirement form dcbnl_setbuffer. */ + u32 set_size_cells; bool lossy; }; +enum mlxsw_sp_hdroom_mode { + MLXSW_SP_HDROOM_MODE_DCB, + MLXSW_SP_HDROOM_MODE_TC, +}; + #define MLXSW_SP_PB_COUNT 10 struct mlxsw_sp_hdroom { + enum mlxsw_sp_hdroom_mode mode; + struct { struct mlxsw_sp_hdroom_prio prio[IEEE_8021Q_MAX_PRIORITIES]; } prios; diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c index 68286cd70c33..37ff29a1686e 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c @@ -304,8 +304,16 @@ void mlxsw_sp_hdroom_prios_reset_buf_idx(struct mlxsw_sp_hdroom *hdroom) { int prio; - for (prio = 0; prio < IEEE_8021QAZ_MAX_TCS; prio++) - hdroom->prios.prio[prio].buf_idx = hdroom->prios.prio[prio].ets_buf_idx; + for (prio = 0; prio < IEEE_8021QAZ_MAX_TCS; prio++) { + switch (hdroom->mode) { + case MLXSW_SP_HDROOM_MODE_DCB: + hdroom->prios.prio[prio].buf_idx = hdroom->prios.prio[prio].ets_buf_idx; + break; + case MLXSW_SP_HDROOM_MODE_TC: + hdroom->prios.prio[prio].buf_idx = hdroom->prios.prio[prio].set_buf_idx; + break; + } + } } void mlxsw_sp_hdroom_bufs_reset_lossiness(struct mlxsw_sp_hdroom *hdroom) @@ -411,7 +419,14 @@ void mlxsw_sp_hdroom_bufs_reset_sizes(struct mlxsw_sp_port *mlxsw_sp_port, delay_cells = mlxsw_sp_port_headroom_8x_adjust(mlxsw_sp_port, delay_cells); buf->thres_cells = thres_cells; - buf->size_cells = thres_cells + delay_cells; + if (hdroom->mode == MLXSW_SP_HDROOM_MODE_DCB) { + buf->size_cells = thres_cells + delay_cells; + } else { + /* Do not allow going below the minimum size, even if + * the user requested it. + */ + buf->size_cells = max(buf->set_size_cells, buf->thres_cells); + } } } @@ -575,6 +590,7 @@ static int mlxsw_sp_port_headroom_init(struct mlxsw_sp_port *mlxsw_sp_port) int prio; hdroom.mtu = mlxsw_sp_port->dev->mtu; + hdroom.mode = MLXSW_SP_HDROOM_MODE_DCB; for (prio = 0; prio < IEEE_8021QAZ_MAX_TCS; prio++) hdroom.prios.prio[prio].lossy = true; From 5ebc6031e6794ea8409cc1d4305f104ac9784398 Mon Sep 17 00:00:00 2001 From: Petr Machata Date: Thu, 17 Sep 2020 09:49:02 +0300 Subject: [PATCH 2/3] mlxsw: spectrum_dcb: Implement dcbnl_setbuffer / getbuffer Add dcbnl_setbuffer, which bounces requests if a headroom is in DCB mode. Implement dcbnl_getbuffer such that it can always be used to determine port-buffer configuration, regardless of headroom mode. Signed-off-by: Petr Machata Reviewed-by: Jiri Pirko Signed-off-by: Ido Schimmel Signed-off-by: David S. Miller --- .../ethernet/mellanox/mlxsw/spectrum_dcb.c | 59 +++++++++++++++++++ 1 file changed, 59 insertions(+) diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_dcb.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_dcb.c index d9a556dbe85e..5f92b1691360 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_dcb.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_dcb.c @@ -592,6 +592,62 @@ err_port_pfc_set: return err; } +static int mlxsw_sp_dcbnl_getbuffer(struct net_device *dev, struct dcbnl_buffer *buf) +{ + struct mlxsw_sp_port *mlxsw_sp_port = netdev_priv(dev); + struct mlxsw_sp_hdroom *hdroom = mlxsw_sp_port->hdroom; + struct mlxsw_sp *mlxsw_sp = mlxsw_sp_port->mlxsw_sp; + int prio; + int i; + + buf->total_size = 0; + + BUILD_BUG_ON(DCBX_MAX_BUFFERS > MLXSW_SP_PB_COUNT); + for (i = 0; i < MLXSW_SP_PB_COUNT; i++) { + u32 bytes = mlxsw_sp_cells_bytes(mlxsw_sp, hdroom->bufs.buf[i].size_cells); + + if (i < DCBX_MAX_BUFFERS) + buf->buffer_size[i] = bytes; + buf->total_size += bytes; + } + + buf->total_size += mlxsw_sp_cells_bytes(mlxsw_sp, hdroom->int_buf.size_cells); + + for (prio = 0; prio < IEEE_8021Q_MAX_PRIORITIES; prio++) + buf->prio2buffer[prio] = hdroom->prios.prio[prio].buf_idx; + + return 0; +} + +static int mlxsw_sp_dcbnl_setbuffer(struct net_device *dev, struct dcbnl_buffer *buf) +{ + struct mlxsw_sp_port *mlxsw_sp_port = netdev_priv(dev); + struct mlxsw_sp *mlxsw_sp = mlxsw_sp_port->mlxsw_sp; + struct mlxsw_sp_hdroom hdroom; + int prio; + int i; + + hdroom = *mlxsw_sp_port->hdroom; + + if (hdroom.mode != MLXSW_SP_HDROOM_MODE_TC) { + netdev_err(dev, "The use of dcbnl_setbuffer is only allowed if egress is configured using TC\n"); + return -EINVAL; + } + + for (prio = 0; prio < IEEE_8021Q_MAX_PRIORITIES; prio++) + hdroom.prios.prio[prio].set_buf_idx = buf->prio2buffer[prio]; + + BUILD_BUG_ON(DCBX_MAX_BUFFERS > MLXSW_SP_PB_COUNT); + for (i = 0; i < DCBX_MAX_BUFFERS; i++) + hdroom.bufs.buf[i].set_size_cells = mlxsw_sp_bytes_cells(mlxsw_sp, + buf->buffer_size[i]); + + mlxsw_sp_hdroom_prios_reset_buf_idx(&hdroom); + mlxsw_sp_hdroom_bufs_reset_lossiness(&hdroom); + mlxsw_sp_hdroom_bufs_reset_sizes(mlxsw_sp_port, &hdroom); + return mlxsw_sp_hdroom_configure(mlxsw_sp_port, &hdroom); +} + static const struct dcbnl_rtnl_ops mlxsw_sp_dcbnl_ops = { .ieee_getets = mlxsw_sp_dcbnl_ieee_getets, .ieee_setets = mlxsw_sp_dcbnl_ieee_setets, @@ -604,6 +660,9 @@ static const struct dcbnl_rtnl_ops mlxsw_sp_dcbnl_ops = { .getdcbx = mlxsw_sp_dcbnl_getdcbx, .setdcbx = mlxsw_sp_dcbnl_setdcbx, + + .dcbnl_getbuffer = mlxsw_sp_dcbnl_getbuffer, + .dcbnl_setbuffer = mlxsw_sp_dcbnl_setbuffer, }; static int mlxsw_sp_port_ets_init(struct mlxsw_sp_port *mlxsw_sp_port) From 509f04ca6298981860544f03bc0e8ae407678438 Mon Sep 17 00:00:00 2001 From: Petr Machata Date: Thu, 17 Sep 2020 09:49:03 +0300 Subject: [PATCH 3/3] mlxsw: spectrum_qdisc: Disable port buffer autoresize with qdiscs There are two interfaces to configure ETS: qdiscs and DCB. Historically, DCB ETS configuration was projected to ingress as well, and configured port buffers. Qdisc was not. Keep qdiscs behaving this way, and if an offloaded qdisc is configured on a port, move this port's headroom to a manual mode, thus allowing configuration of port buffers through dcbnl_setbuffer. Signed-off-by: Petr Machata Reviewed-by: Jiri Pirko Signed-off-by: Ido Schimmel Signed-off-by: David S. Miller --- .../ethernet/mellanox/mlxsw/spectrum_qdisc.c | 34 ++++++++++++++++++- 1 file changed, 33 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_qdisc.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_qdisc.c index 964fd444bb10..fd672c6c9133 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_qdisc.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_qdisc.c @@ -140,18 +140,31 @@ static int mlxsw_sp_qdisc_destroy(struct mlxsw_sp_port *mlxsw_sp_port, struct mlxsw_sp_qdisc *mlxsw_sp_qdisc) { + struct mlxsw_sp_qdisc *root_qdisc = &mlxsw_sp_port->qdisc->root_qdisc; + int err_hdroom = 0; int err = 0; if (!mlxsw_sp_qdisc) return 0; + if (root_qdisc == mlxsw_sp_qdisc) { + struct mlxsw_sp_hdroom hdroom = *mlxsw_sp_port->hdroom; + + hdroom.mode = MLXSW_SP_HDROOM_MODE_DCB; + mlxsw_sp_hdroom_prios_reset_buf_idx(&hdroom); + mlxsw_sp_hdroom_bufs_reset_lossiness(&hdroom); + mlxsw_sp_hdroom_bufs_reset_sizes(mlxsw_sp_port, &hdroom); + err_hdroom = mlxsw_sp_hdroom_configure(mlxsw_sp_port, &hdroom); + } + if (mlxsw_sp_qdisc->ops && mlxsw_sp_qdisc->ops->destroy) err = mlxsw_sp_qdisc->ops->destroy(mlxsw_sp_port, mlxsw_sp_qdisc); mlxsw_sp_qdisc->handle = TC_H_UNSPEC; mlxsw_sp_qdisc->ops = NULL; - return err; + + return err_hdroom ?: err; } static int @@ -159,6 +172,8 @@ mlxsw_sp_qdisc_replace(struct mlxsw_sp_port *mlxsw_sp_port, u32 handle, struct mlxsw_sp_qdisc *mlxsw_sp_qdisc, struct mlxsw_sp_qdisc_ops *ops, void *params) { + struct mlxsw_sp_qdisc *root_qdisc = &mlxsw_sp_port->qdisc->root_qdisc; + struct mlxsw_sp_hdroom orig_hdroom; int err; if (mlxsw_sp_qdisc->ops && mlxsw_sp_qdisc->ops->type != ops->type) @@ -168,6 +183,21 @@ mlxsw_sp_qdisc_replace(struct mlxsw_sp_port *mlxsw_sp_port, u32 handle, * new one. */ mlxsw_sp_qdisc_destroy(mlxsw_sp_port, mlxsw_sp_qdisc); + + orig_hdroom = *mlxsw_sp_port->hdroom; + if (root_qdisc == mlxsw_sp_qdisc) { + struct mlxsw_sp_hdroom hdroom = orig_hdroom; + + hdroom.mode = MLXSW_SP_HDROOM_MODE_TC; + mlxsw_sp_hdroom_prios_reset_buf_idx(&hdroom); + mlxsw_sp_hdroom_bufs_reset_lossiness(&hdroom); + mlxsw_sp_hdroom_bufs_reset_sizes(mlxsw_sp_port, &hdroom); + + err = mlxsw_sp_hdroom_configure(mlxsw_sp_port, &hdroom); + if (err) + goto err_hdroom_configure; + } + err = ops->check_params(mlxsw_sp_port, mlxsw_sp_qdisc, params); if (err) goto err_bad_param; @@ -191,6 +221,8 @@ mlxsw_sp_qdisc_replace(struct mlxsw_sp_port *mlxsw_sp_port, u32 handle, err_bad_param: err_config: + mlxsw_sp_hdroom_configure(mlxsw_sp_port, &orig_hdroom); +err_hdroom_configure: if (mlxsw_sp_qdisc->handle == handle && ops->unoffload) ops->unoffload(mlxsw_sp_port, mlxsw_sp_qdisc, params);