[bpf-next V2 PATCH 00/14] xdp: new XDP rx-queue info concept

[bpf-next V2 PATCH 00/14] xdp: new XDP rx-queue info concept

[Jesper Dangaard Brouer]

V2:
* Changed API exposed to drivers
  - Removed invocation of "init" in drivers, and only call "reg"
    (Suggested by Saeed)
  - Allow "reg" to fail and handle this in drivers
    (Suggested by David Ahern)
* Removed the SINKQ qtype, instead allow to register as "unused"
* Also fixed some drivers during testing on actual HW (noted in patches)

There is a need for XDP to know more about the RX-queue a given XDP
frames have arrived on.  For both the XDP bpf-prog and kernel side.

Instead of extending struct xdp_buff each time new info is needed,
this patchset takes a different approach.  Struct xdp_buff is only
extended with a pointer to a struct xdp_rxq_info (allowing for easier
extending this later).  This xdp_rxq_info contains information related
to how the driver have setup the individual RX-queue's.  This is
read-mostly information, and all xdp_buff frames (in drivers
napi_poll) point to the same xdp_rxq_info (per RX-queue).

We stress this data/cache-line is for read-mostly info.  This is NOT
for dynamic per packet info, use the data_meta for such use-cases.

This patchset start out small, and only expose ingress_ifindex and the
RX-queue index to the XDP/BPF program. Access to tangible info like
the ingress ifindex and RX queue index, is fairly easy to comprehent.
The other future use-cases could allow XDP frames to be recycled back
to the originating device driver, by providing info on RX device and
queue number.

As XDP doesn't have driver feature flags, and eBPF code due to
bpf-tail-calls cannot determine that XDP driver invoke it, this
patchset have to update every driver that support XDP.

For driver developers (review individual driver patches!):

The xdp_rxq_info is tied to the drivers RX-ring(s). Whenever a RX-ring
modification require (temporary) stopping RX frames, then the
xdp_rxq_info should (likely) also be unregistred and re-registered,
especially if reallocating the pages in the ring. Make sure ethtool
set_channels does the right thing. When replacing XDP prog, if and
only if RX-ring need to be changed, then also re-register the
xdp_rxq_info.

I'm Cc'ing the individual driver patches to the registered maintainers.

Testing:

I've only tested the NIC drivers I have hardware for.  The general
test procedure is to (DUT = Device Under Test):
 (1) run pktgen script pktgen_sample04_many_flows.sh       (against DUT)
 (2) run samples/bpf program xdp_rxq_info --dev $DEV       (on DUT)
 (3) runtime modify number of NIC queues via ethtool -L    (on DUT)
 (4) runtime modify number of NIC ring-size via ethtool -G (on DUT)

Patch based on git tree bpf-next (at commit c475ffad58a8a2):
 https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git/

---

Jesper Dangaard Brouer (14):
      xdp: base API for new XDP rx-queue info concept
      xdp/mlx5: setup xdp_rxq_info
      i40e: setup xdp_rxq_info
      ixgbe: setup xdp_rxq_info
      xdp/qede: setup xdp_rxq_info and intro xdp_rxq_info_is_reg
      mlx4: setup xdp_rxq_info
      bnxt_en: setup xdp_rxq_info
      nfp: setup xdp_rxq_info
      thunderx: setup xdp_rxq_info
      tun: setup xdp_rxq_info
      virtio_net: setup xdp_rxq_info
      xdp: generic XDP handling of xdp_rxq_info
      bpf: finally expose xdp_rxq_info to XDP bpf-programs
      samples/bpf: program demonstrating access to xdp_rxq_info


 drivers/net/ethernet/broadcom/bnxt/bnxt.c          |   10 
 drivers/net/ethernet/broadcom/bnxt/bnxt.h          |    2 
 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c      |    1 
 drivers/net/ethernet/cavium/thunder/nicvf_main.c   |   11 
 drivers/net/ethernet/cavium/thunder/nicvf_queues.c |    4 
 drivers/net/ethernet/cavium/thunder/nicvf_queues.h |    2 
 drivers/net/ethernet/intel/i40e/i40e_ethtool.c     |    2 
 drivers/net/ethernet/intel/i40e/i40e_txrx.c        |   18 +
 drivers/net/ethernet/intel/i40e/i40e_txrx.h        |    3 
 drivers/net/ethernet/intel/ixgbe/ixgbe.h           |    2 
 drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c   |    4 
 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c      |   10 
 drivers/net/ethernet/mellanox/mlx4/en_netdev.c     |    3 
 drivers/net/ethernet/mellanox/mlx4/en_rx.c         |   13 
 drivers/net/ethernet/mellanox/mlx4/mlx4_en.h       |    4 
 drivers/net/ethernet/mellanox/mlx5/core/en.h       |    4 
 drivers/net/ethernet/mellanox/mlx5/core/en_main.c  |    9 
 drivers/net/ethernet/mellanox/mlx5/core/en_rx.c    |    1 
 drivers/net/ethernet/netronome/nfp/nfp_net.h       |    5 
 .../net/ethernet/netronome/nfp/nfp_net_common.c    |   10 
 drivers/net/ethernet/qlogic/qede/qede.h            |    2 
 drivers/net/ethernet/qlogic/qede/qede_fp.c         |    1 
 drivers/net/ethernet/qlogic/qede/qede_main.c       |   10 
 drivers/net/tun.c                                  |   24 +
 drivers/net/virtio_net.c                           |   12 
 include/linux/filter.h                             |    2 
 include/linux/netdevice.h                          |    2 
 include/net/xdp.h                                  |   48 ++
 include/uapi/linux/bpf.h                           |    3 
 net/core/Makefile                                  |    2 
 net/core/dev.c                                     |   69 ++-
 net/core/filter.c                                  |   19 +
 net/core/xdp.c                                     |   74 +++
 samples/bpf/Makefile                               |    4 
 samples/bpf/xdp_rxq_info_kern.c                    |   96 ++++
 samples/bpf/xdp_rxq_info_user.c                    |  532 ++++++++++++++++++++
 36 files changed, 990 insertions(+), 28 deletions(-)
 create mode 100644 include/net/xdp.h
 create mode 100644 net/core/xdp.c
 create mode 100644 samples/bpf/xdp_rxq_info_kern.c
 create mode 100644 samples/bpf/xdp_rxq_info_user.c

[bpf-next V2 PATCH 01/14] xdp: base API for new XDP rx-queue info concept

[Jesper Dangaard Brouer]

This patch only introduce the core data structures and API functions.
All XDP enabled drivers must use the API before this info can used.

There is a need for XDP to know more about the RX-queue a given XDP
frames have arrived on.  For both the XDP bpf-prog and kernel side.

Instead of extending xdp_buff each time new info is needed, the patch
creates a separate read-mostly struct xdp_rxq_info, that contains this
info.  We stress this data/cache-line is for read-only info.  This is
NOT for dynamic per packet info, use the data_meta for such use-cases.

The performance advantage is this info can be setup at RX-ring init
time, instead of updating N-members in xdp_buff.  A possible (driver
level) micro optimization is that xdp_buff->rxq assignment could be
done once per XDP/NAPI loop.  The extra pointer deref only happens for
program needing access to this info (thus, no slowdown to existing
use-cases).

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 include/linux/filter.h |    2 +
 include/net/xdp.h      |   47 +++++++++++++++++++++++++++++++++
 net/core/Makefile      |    2 +
 net/core/xdp.c         |   68 ++++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 118 insertions(+), 1 deletion(-)
 create mode 100644 include/net/xdp.h
 create mode 100644 net/core/xdp.c

diff --git a/include/linux/filter.h b/include/linux/filter.h
index 2b0df2703671..425056c7f96c 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -20,6 +20,7 @@
 #include <linux/set_memory.h>
 #include <linux/kallsyms.h>
 
+#include <net/xdp.h>
 #include <net/sch_generic.h>
 
 #include <uapi/linux/filter.h>
@@ -503,6 +504,7 @@ struct xdp_buff {
 	void *data_end;
 	void *data_meta;
 	void *data_hard_start;
+	struct xdp_rxq_info *rxq;
 };
 
 /* Compute the linear packet data range [data, data_end) which
diff --git a/include/net/xdp.h b/include/net/xdp.h
new file mode 100644
index 000000000000..8c6e83293bba
--- /dev/null
+++ b/include/net/xdp.h
@@ -0,0 +1,47 @@
+/* include/net/xdp.h
+ *
+ * Copyright (c) 2017 Jesper Dangaard Brouer, Red Hat Inc.
+ * Released under terms in GPL version 2.  See COPYING.
+ */
+#ifndef __LINUX_NET_XDP_H__
+#define __LINUX_NET_XDP_H__
+
+/**
+ * DOC: XDP RX-queue information
+ *
+ * The XDP RX-queue info (xdp_rxq_info) is associated with the driver
+ * level RX-ring queues.  It is information that is specific to how
+ * the driver have configured a given RX-ring queue.
+ *
+ * Each xdp_buff frame received in the driver carry a (pointer)
+ * reference to this xdp_rxq_info structure.  This provides the XDP
+ * data-path read-access to RX-info for both kernel and bpf-side
+ * (limited subset).
+ *
+ * For now, direct access is only safe while running in NAPI/softirq
+ * context.
+ *
+ * The driver usage API is an init, register and unregister API.
+ *
+ * The struct is not directly tied to the XDP prog.  A new XDP prog
+ * can be attached as long as it doesn't change the underlying
+ * RX-ring.  If the RX-ring does change significantly, the NIC driver
+ * naturally need to stop the RX-ring before purging and reallocating
+ * memory.  In that process the driver MUST call unregistor (which
+ * also apply for driver shutdown and unload).  The init and register
+ * API is also mandatory during RX-ring setup.
+ */
+
+struct xdp_rxq_info {
+	struct net_device *dev;
+	u32 queue_index;
+	u32 reg_state;
+} ____cacheline_aligned; /* perf critical, avoid false-sharing */
+
+void xdp_rxq_info_init(struct xdp_rxq_info *xdp_rxq);
+int xdp_rxq_info_reg(struct xdp_rxq_info *xdp_rxq,
+		     struct net_device *dev, u32 queue_index);
+void xdp_rxq_info_unreg(struct xdp_rxq_info *xdp_rxq);
+void xdp_rxq_info_unused(struct xdp_rxq_info *xdp_rxq);
+
+#endif /* __LINUX_NET_XDP_H__ */
diff --git a/net/core/Makefile b/net/core/Makefile
index 1fd0a9c88b1b..6dbbba8c57ae 100644
--- a/net/core/Makefile
+++ b/net/core/Makefile
@@ -11,7 +11,7 @@ obj-$(CONFIG_SYSCTL) += sysctl_net_core.o
 obj-y		     += dev.o ethtool.o dev_addr_lists.o dst.o netevent.o \
 			neighbour.o rtnetlink.o utils.o link_watch.o filter.o \
 			sock_diag.o dev_ioctl.o tso.o sock_reuseport.o \
-			fib_notifier.o
+			fib_notifier.o xdp.o
 
 obj-y += net-sysfs.o
 obj-$(CONFIG_PROC_FS) += net-procfs.o
diff --git a/net/core/xdp.c b/net/core/xdp.c
new file mode 100644
index 000000000000..dde541b71aaa
--- /dev/null
+++ b/net/core/xdp.c
@@ -0,0 +1,68 @@
+/* net/core/xdp.c
+ *
+ * Copyright (c) 2017 Jesper Dangaard Brouer, Red Hat Inc.
+ * Released under terms in GPL version 2.  See COPYING.
+ */
+#include <linux/types.h>
+#include <linux/mm.h>
+
+#include <net/xdp.h>
+
+#define REG_STATE_NEW		0x0
+#define REG_STATE_REGISTERED	0x1
+#define REG_STATE_UNREGISTERED	0x2
+#define REG_STATE_UNUSED	0x3
+
+void xdp_rxq_info_unreg(struct xdp_rxq_info *xdp_rxq)
+{
+	/* Simplify driver cleanup code paths, allow unreg "unused" */
+	if (xdp_rxq->reg_state == REG_STATE_UNUSED)
+		return;
+
+	WARN(!(xdp_rxq->reg_state == REG_STATE_REGISTERED), "Driver BUG");
+
+	xdp_rxq->reg_state = REG_STATE_UNREGISTERED;
+	xdp_rxq->dev = NULL;
+}
+EXPORT_SYMBOL_GPL(xdp_rxq_info_unreg);
+
+void xdp_rxq_info_init(struct xdp_rxq_info *xdp_rxq)
+{
+	memset(xdp_rxq, 0, sizeof(*xdp_rxq));
+}
+EXPORT_SYMBOL_GPL(xdp_rxq_info_init);
+
+/* Returns 0 on success, negative on failure */
+int xdp_rxq_info_reg(struct xdp_rxq_info *xdp_rxq,
+		     struct net_device *dev, u32 queue_index)
+{
+	if (xdp_rxq->reg_state == REG_STATE_UNUSED) {
+		WARN(1, "Driver promised not to register this");
+		return -EINVAL;
+	}
+
+	if (xdp_rxq->reg_state == REG_STATE_REGISTERED) {
+		WARN(1, "Missing unregister, handled but fix driver");
+		xdp_rxq_info_unreg(xdp_rxq);
+	}
+
+	if (!dev) {
+		WARN(1, "Missing net_device from driver");
+		return -ENODEV;
+	}
+
+	/* State either UNREGISTERED or NEW */
+	xdp_rxq_info_init(xdp_rxq);
+	xdp_rxq->dev = dev;
+	xdp_rxq->queue_index = queue_index;
+
+	xdp_rxq->reg_state = REG_STATE_REGISTERED;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(xdp_rxq_info_reg);
+
+void xdp_rxq_info_unused(struct xdp_rxq_info *xdp_rxq)
+{
+	xdp_rxq->reg_state = REG_STATE_UNUSED;
+}
+EXPORT_SYMBOL_GPL(xdp_rxq_info_unused);

[bpf-next V2 PATCH 02/14] xdp/mlx5: setup xdp_rxq_info

[Jesper Dangaard Brouer]

The mlx5 driver have a special drop-RQ queue (one per interface) that
simply drops all incoming traffic. It helps driver keep other HW
objects (flow steering) alive upon down/up operations.  It is
temporarily pointed by flow steering objects during the interface
setup, and when interface is down. It lacks many fields that are set
in a regular RQ (for example its state is never switched to
MLX5_RQC_STATE_RDY). (Thanks to Tariq Toukan for explanation).

The XDP RX-queue info for this drop-RQ marked as unused, which
allow us to use the same takedown/free code path as other RX-queues.

Driver hook points for xdp_rxq_info:
 * reg   : mlx5e_alloc_rq()
 * unused: mlx5e_alloc_drop_rq()
 * unreg : mlx5e_free_rq()

Tested on actual hardware with samples/bpf program

Cc: Saeed Mahameed <saeedm@mellanox.com>
Cc: Matan Barak <matanb@mellanox.com>
Cc: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 drivers/net/ethernet/mellanox/mlx5/core/en.h      |    4 ++++
 drivers/net/ethernet/mellanox/mlx5/core/en_main.c |    9 +++++++++
 drivers/net/ethernet/mellanox/mlx5/core/en_rx.c   |    1 +
 3 files changed, 14 insertions(+)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h
index c0872b3284cb..405b09db2a84 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h
@@ -46,6 +46,7 @@
 #include <linux/mlx5/transobj.h>
 #include <linux/rhashtable.h>
 #include <net/switchdev.h>
+#include <net/xdp.h>
 #include "wq.h"
 #include "mlx5_core.h"
 #include "en_stats.h"
@@ -568,6 +569,9 @@ struct mlx5e_rq {
 	u32                    rqn;
 	struct mlx5_core_dev  *mdev;
 	struct mlx5_core_mkey  umr_mkey;
+
+	/* XDP read-mostly */
+	struct xdp_rxq_info    xdp_rxq;
 } ____cacheline_aligned_in_smp;
 
 struct mlx5e_channel {
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index 0f5c012de52e..128cb9a32549 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -589,6 +589,9 @@ static int mlx5e_alloc_rq(struct mlx5e_channel *c,
 		goto err_rq_wq_destroy;
 	}
 
+	if (xdp_rxq_info_reg(&rq->xdp_rxq, rq->netdev, rq->ix) < 0)
+		goto err_rq_wq_destroy;
+
 	rq->buff.map_dir = rq->xdp_prog ? DMA_BIDIRECTIONAL : DMA_FROM_DEVICE;
 	rq->buff.headroom = params->rq_headroom;
 
@@ -695,6 +698,7 @@ static int mlx5e_alloc_rq(struct mlx5e_channel *c,
 err_rq_wq_destroy:
 	if (rq->xdp_prog)
 		bpf_prog_put(rq->xdp_prog);
+	xdp_rxq_info_unreg(&rq->xdp_rxq);
 	mlx5_wq_destroy(&rq->wq_ctrl);
 
 	return err;
@@ -707,6 +711,8 @@ static void mlx5e_free_rq(struct mlx5e_rq *rq)
 	if (rq->xdp_prog)
 		bpf_prog_put(rq->xdp_prog);
 
+	xdp_rxq_info_unreg(&rq->xdp_rxq);
+
 	switch (rq->wq_type) {
 	case MLX5_WQ_TYPE_LINKED_LIST_STRIDING_RQ:
 		mlx5e_rq_free_mpwqe_info(rq);
@@ -2768,6 +2774,9 @@ static int mlx5e_alloc_drop_rq(struct mlx5_core_dev *mdev,
 	if (err)
 		return err;
 
+	/* Mark as unused given "Drop-RQ" packets never reach XDP */
+	xdp_rxq_info_unused(&rq->xdp_rxq);
+
 	rq->mdev = mdev;
 
 	return 0;
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
index 5b499c7a698f..7b38480811d4 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
@@ -812,6 +812,7 @@ static inline int mlx5e_xdp_handle(struct mlx5e_rq *rq,
 	xdp_set_data_meta_invalid(&xdp);
 	xdp.data_end = xdp.data + *len;
 	xdp.data_hard_start = va;
+	xdp.rxq = &rq->xdp_rxq;
 
 	act = bpf_prog_run_xdp(prog, &xdp);
 	switch (act) {

[bpf-next V2 PATCH 03/14] i40e: setup xdp_rxq_info

[Jesper Dangaard Brouer]

The i40e driver have a special "FDIR" RX-ring (I40E_VSI_FDIR) which is
a sideband channel for configuring/updating the flow director tables.
This (i40e_vsi_)type does not invoke XDP-ebpf code. Thus, mark this
type as a XDP RX-queue type RXQ_TYPE_SINK.

Driver hook points for xdp_rxq_info:
 * reg  : i40e_setup_rx_descriptors (via i40e_vsi_setup_rx_resources)
 * unreg: i40e_free_rx_resources    (via i40e_vsi_free_rx_resources)

Tested on actual hardware with samples/bpf program.

V2: Fixed bug in i40e_set_ringparam

Cc: intel-wired-lan@lists.osuosl.org
Cc: Björn Töpel <bjorn.topel@intel.com>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 drivers/net/ethernet/intel/i40e/i40e_ethtool.c |    2 ++
 drivers/net/ethernet/intel/i40e/i40e_txrx.c    |   18 ++++++++++++++++--
 drivers/net/ethernet/intel/i40e/i40e_txrx.h    |    3 +++
 3 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
index 5f6cf7212d4f..cfd788b4fd7a 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
@@ -1585,6 +1585,8 @@ static int i40e_set_ringparam(struct net_device *netdev,
 			 */
 			rx_rings[i].desc = NULL;
 			rx_rings[i].rx_bi = NULL;
+			/* Clear cloned XDP RX-queue info before setup call */
+			memset(&rx_rings[i].xdp_rxq, 0, sizeof(rx_rings[i].xdp_rxq));
 			/* this is to allow wr32 to have something to write to
 			 * during early allocation of Rx buffers
 			 */
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index 4566d66ffc7c..2a8a85e3ae8f 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -27,6 +27,7 @@
 #include <linux/prefetch.h>
 #include <net/busy_poll.h>
 #include <linux/bpf_trace.h>
+#include <net/xdp.h>
 #include "i40e.h"
 #include "i40e_trace.h"
 #include "i40e_prototype.h"
@@ -1236,6 +1237,8 @@ void i40e_clean_rx_ring(struct i40e_ring *rx_ring)
 void i40e_free_rx_resources(struct i40e_ring *rx_ring)
 {
 	i40e_clean_rx_ring(rx_ring);
+	if (rx_ring->vsi->type == I40E_VSI_MAIN)
+		xdp_rxq_info_unreg(&rx_ring->xdp_rxq);
 	rx_ring->xdp_prog = NULL;
 	kfree(rx_ring->rx_bi);
 	rx_ring->rx_bi = NULL;
@@ -1256,6 +1259,7 @@ void i40e_free_rx_resources(struct i40e_ring *rx_ring)
 int i40e_setup_rx_descriptors(struct i40e_ring *rx_ring)
 {
 	struct device *dev = rx_ring->dev;
+	int err = -ENOMEM;
 	int bi_size;
 
 	/* warn if we are about to overwrite the pointer */
@@ -1283,13 +1287,21 @@ int i40e_setup_rx_descriptors(struct i40e_ring *rx_ring)
 	rx_ring->next_to_clean = 0;
 	rx_ring->next_to_use = 0;
 
+	/* XDP RX-queue info only needed for RX rings exposed to XDP */
+	if (rx_ring->vsi->type == I40E_VSI_MAIN) {
+		err = xdp_rxq_info_reg(&rx_ring->xdp_rxq, rx_ring->netdev,
+				       rx_ring->queue_index);
+		if (err < 0)
+			goto err;
+	}
+
 	rx_ring->xdp_prog = rx_ring->vsi->xdp_prog;
 
 	return 0;
 err:
 	kfree(rx_ring->rx_bi);
 	rx_ring->rx_bi = NULL;
-	return -ENOMEM;
+	return err;
 }
 
 /**
@@ -2068,11 +2080,13 @@ static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget)
 	struct sk_buff *skb = rx_ring->skb;
 	u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
 	bool failure = false, xdp_xmit = false;
+	struct xdp_buff xdp;
+
+	xdp.rxq = &rx_ring->xdp_rxq;
 
 	while (likely(total_rx_packets < (unsigned int)budget)) {
 		struct i40e_rx_buffer *rx_buffer;
 		union i40e_rx_desc *rx_desc;
-		struct xdp_buff xdp;
 		unsigned int size;
 		u16 vlan_tag;
 		u8 rx_ptype;
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.h b/drivers/net/ethernet/intel/i40e/i40e_txrx.h
index fbae1182e2ea..2d08760fc4ce 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.h
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.h
@@ -27,6 +27,8 @@
 #ifndef _I40E_TXRX_H_
 #define _I40E_TXRX_H_
 
+#include <net/xdp.h>
+
 /* Interrupt Throttling and Rate Limiting Goodies */
 
 #define I40E_MAX_ITR               0x0FF0  /* reg uses 2 usec resolution */
@@ -428,6 +430,7 @@ struct i40e_ring {
 					 */
 
 	struct i40e_channel *ch;
+	struct xdp_rxq_info xdp_rxq;
 } ____cacheline_internodealigned_in_smp;
 
 static inline bool ring_uses_build_skb(struct i40e_ring *ring)

[Intel-wired-lan] [bpf-next V2 PATCH 03/14] i40e: setup xdp_rxq_info

[Jesper Dangaard Brouer]

The i40e driver have a special "FDIR" RX-ring (I40E_VSI_FDIR) which is
a sideband channel for configuring/updating the flow director tables.
This (i40e_vsi_)type does not invoke XDP-ebpf code. Thus, mark this
type as a XDP RX-queue type RXQ_TYPE_SINK.

Driver hook points for xdp_rxq_info:
 * reg  : i40e_setup_rx_descriptors (via i40e_vsi_setup_rx_resources)
 * unreg: i40e_free_rx_resources    (via i40e_vsi_free_rx_resources)

Tested on actual hardware with samples/bpf program.

V2: Fixed bug in i40e_set_ringparam

Cc: intel-wired-lan at lists.osuosl.org
Cc: Bj?rn T?pel <bjorn.topel@intel.com>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 drivers/net/ethernet/intel/i40e/i40e_ethtool.c |    2 ++
 drivers/net/ethernet/intel/i40e/i40e_txrx.c    |   18 ++++++++++++++++--
 drivers/net/ethernet/intel/i40e/i40e_txrx.h    |    3 +++
 3 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
index 5f6cf7212d4f..cfd788b4fd7a 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
@@ -1585,6 +1585,8 @@ static int i40e_set_ringparam(struct net_device *netdev,
 			 */
 			rx_rings[i].desc = NULL;
 			rx_rings[i].rx_bi = NULL;
+			/* Clear cloned XDP RX-queue info before setup call */
+			memset(&rx_rings[i].xdp_rxq, 0, sizeof(rx_rings[i].xdp_rxq));
 			/* this is to allow wr32 to have something to write to
 			 * during early allocation of Rx buffers
 			 */
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index 4566d66ffc7c..2a8a85e3ae8f 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -27,6 +27,7 @@
 #include <linux/prefetch.h>
 #include <net/busy_poll.h>
 #include <linux/bpf_trace.h>
+#include <net/xdp.h>
 #include "i40e.h"
 #include "i40e_trace.h"
 #include "i40e_prototype.h"
@@ -1236,6 +1237,8 @@ void i40e_clean_rx_ring(struct i40e_ring *rx_ring)
 void i40e_free_rx_resources(struct i40e_ring *rx_ring)
 {
 	i40e_clean_rx_ring(rx_ring);
+	if (rx_ring->vsi->type == I40E_VSI_MAIN)
+		xdp_rxq_info_unreg(&rx_ring->xdp_rxq);
 	rx_ring->xdp_prog = NULL;
 	kfree(rx_ring->rx_bi);
 	rx_ring->rx_bi = NULL;
@@ -1256,6 +1259,7 @@ void i40e_free_rx_resources(struct i40e_ring *rx_ring)
 int i40e_setup_rx_descriptors(struct i40e_ring *rx_ring)
 {
 	struct device *dev = rx_ring->dev;
+	int err = -ENOMEM;
 	int bi_size;
 
 	/* warn if we are about to overwrite the pointer */
@@ -1283,13 +1287,21 @@ int i40e_setup_rx_descriptors(struct i40e_ring *rx_ring)
 	rx_ring->next_to_clean = 0;
 	rx_ring->next_to_use = 0;
 
+	/* XDP RX-queue info only needed for RX rings exposed to XDP */
+	if (rx_ring->vsi->type == I40E_VSI_MAIN) {
+		err = xdp_rxq_info_reg(&rx_ring->xdp_rxq, rx_ring->netdev,
+				       rx_ring->queue_index);
+		if (err < 0)
+			goto err;
+	}
+
 	rx_ring->xdp_prog = rx_ring->vsi->xdp_prog;
 
 	return 0;
 err:
 	kfree(rx_ring->rx_bi);
 	rx_ring->rx_bi = NULL;
-	return -ENOMEM;
+	return err;
 }
 
 /**
@@ -2068,11 +2080,13 @@ static int i40e_clean_rx_irq(struct i40e_ring *rx_ring, int budget)
 	struct sk_buff *skb = rx_ring->skb;
 	u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
 	bool failure = false, xdp_xmit = false;
+	struct xdp_buff xdp;
+
+	xdp.rxq = &rx_ring->xdp_rxq;
 
 	while (likely(total_rx_packets < (unsigned int)budget)) {
 		struct i40e_rx_buffer *rx_buffer;
 		union i40e_rx_desc *rx_desc;
-		struct xdp_buff xdp;
 		unsigned int size;
 		u16 vlan_tag;
 		u8 rx_ptype;
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.h b/drivers/net/ethernet/intel/i40e/i40e_txrx.h
index fbae1182e2ea..2d08760fc4ce 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.h
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.h
@@ -27,6 +27,8 @@
 #ifndef _I40E_TXRX_H_
 #define _I40E_TXRX_H_
 
+#include <net/xdp.h>
+
 /* Interrupt Throttling and Rate Limiting Goodies */
 
 #define I40E_MAX_ITR               0x0FF0  /* reg uses 2 usec resolution */
@@ -428,6 +430,7 @@ struct i40e_ring {
 					 */
 
 	struct i40e_channel *ch;
+	struct xdp_rxq_info xdp_rxq;
 } ____cacheline_internodealigned_in_smp;
 
 static inline bool ring_uses_build_skb(struct i40e_ring *ring)

[bpf-next V2 PATCH 04/14] ixgbe: setup xdp_rxq_info

[Jesper Dangaard Brouer]

Driver hook points for xdp_rxq_info:
 * reg  : ixgbe_setup_rx_resources()
 * unreg: ixgbe_free_rx_resources()

Tested on actual hardware.

V2: Fix ixgbe_set_ringparam, clear xdp_rxq_info in temp_ring

Cc: intel-wired-lan@lists.osuosl.org
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Cc: Alexander Duyck <alexander.duyck@gmail.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 drivers/net/ethernet/intel/ixgbe/ixgbe.h         |    2 ++
 drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c |    4 ++++
 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c    |   10 +++++++++-
 3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe.h b/drivers/net/ethernet/intel/ixgbe/ixgbe.h
index 468c3555a629..8611763d6129 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe.h
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe.h
@@ -53,6 +53,7 @@
 #include <linux/dca.h>
 #endif
 
+#include <net/xdp.h>
 #include <net/busy_poll.h>
 
 /* common prefix used by pr_<> macros */
@@ -371,6 +372,7 @@ struct ixgbe_ring {
 		struct ixgbe_tx_queue_stats tx_stats;
 		struct ixgbe_rx_queue_stats rx_stats;
 	};
+	struct xdp_rxq_info xdp_rxq;
 } ____cacheline_internodealigned_in_smp;
 
 enum ixgbe_ring_f_enum {
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
index 0aad1c2a3667..0aaf70b3cfcd 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
@@ -1156,6 +1156,10 @@ static int ixgbe_set_ringparam(struct net_device *netdev,
 			memcpy(&temp_ring[i], adapter->rx_ring[i],
 			       sizeof(struct ixgbe_ring));
 
+			/* Clear copied XDP RX-queue info */
+			memset(&temp_ring[i].xdp_rxq, 0,
+			       sizeof(temp_ring[i].xdp_rxq));
+
 			temp_ring[i].count = new_rx_count;
 			err = ixgbe_setup_rx_resources(adapter, &temp_ring[i]);
 			if (err) {
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 7737a05c717c..95aba975b391 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -2318,12 +2318,14 @@ static int ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector,
 #endif /* IXGBE_FCOE */
 	u16 cleaned_count = ixgbe_desc_unused(rx_ring);
 	bool xdp_xmit = false;
+	struct xdp_buff xdp;
+
+	xdp.rxq = &rx_ring->xdp_rxq;
 
 	while (likely(total_rx_packets < budget)) {
 		union ixgbe_adv_rx_desc *rx_desc;
 		struct ixgbe_rx_buffer *rx_buffer;
 		struct sk_buff *skb;
-		struct xdp_buff xdp;
 		unsigned int size;
 
 		/* return some buffers to hardware, one at a time is too slow */
@@ -6444,6 +6446,11 @@ int ixgbe_setup_rx_resources(struct ixgbe_adapter *adapter,
 	rx_ring->next_to_clean = 0;
 	rx_ring->next_to_use = 0;
 
+	/* XDP RX-queue info */
+	if (xdp_rxq_info_reg(&rx_ring->xdp_rxq, adapter->netdev,
+			     rx_ring->queue_index) < 0)
+		goto err;
+
 	rx_ring->xdp_prog = adapter->xdp_prog;
 
 	return 0;
@@ -6541,6 +6548,7 @@ void ixgbe_free_rx_resources(struct ixgbe_ring *rx_ring)
 	ixgbe_clean_rx_ring(rx_ring);
 
 	rx_ring->xdp_prog = NULL;
+	xdp_rxq_info_unreg(&rx_ring->xdp_rxq);
 	vfree(rx_ring->rx_buffer_info);
 	rx_ring->rx_buffer_info = NULL;
 

[Intel-wired-lan] [bpf-next V2 PATCH 04/14] ixgbe: setup xdp_rxq_info

[Jesper Dangaard Brouer]

Driver hook points for xdp_rxq_info:
 * reg  : ixgbe_setup_rx_resources()
 * unreg: ixgbe_free_rx_resources()

Tested on actual hardware.

V2: Fix ixgbe_set_ringparam, clear xdp_rxq_info in temp_ring

Cc: intel-wired-lan at lists.osuosl.org
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Cc: Alexander Duyck <alexander.duyck@gmail.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 drivers/net/ethernet/intel/ixgbe/ixgbe.h         |    2 ++
 drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c |    4 ++++
 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c    |   10 +++++++++-
 3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe.h b/drivers/net/ethernet/intel/ixgbe/ixgbe.h
index 468c3555a629..8611763d6129 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe.h
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe.h
@@ -53,6 +53,7 @@
 #include <linux/dca.h>
 #endif
 
+#include <net/xdp.h>
 #include <net/busy_poll.h>
 
 /* common prefix used by pr_<> macros */
@@ -371,6 +372,7 @@ struct ixgbe_ring {
 		struct ixgbe_tx_queue_stats tx_stats;
 		struct ixgbe_rx_queue_stats rx_stats;
 	};
+	struct xdp_rxq_info xdp_rxq;
 } ____cacheline_internodealigned_in_smp;
 
 enum ixgbe_ring_f_enum {
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
index 0aad1c2a3667..0aaf70b3cfcd 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
@@ -1156,6 +1156,10 @@ static int ixgbe_set_ringparam(struct net_device *netdev,
 			memcpy(&temp_ring[i], adapter->rx_ring[i],
 			       sizeof(struct ixgbe_ring));
 
+			/* Clear copied XDP RX-queue info */
+			memset(&temp_ring[i].xdp_rxq, 0,
+			       sizeof(temp_ring[i].xdp_rxq));
+
 			temp_ring[i].count = new_rx_count;
 			err = ixgbe_setup_rx_resources(adapter, &temp_ring[i]);
 			if (err) {
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 7737a05c717c..95aba975b391 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -2318,12 +2318,14 @@ static int ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector,
 #endif /* IXGBE_FCOE */
 	u16 cleaned_count = ixgbe_desc_unused(rx_ring);
 	bool xdp_xmit = false;
+	struct xdp_buff xdp;
+
+	xdp.rxq = &rx_ring->xdp_rxq;
 
 	while (likely(total_rx_packets < budget)) {
 		union ixgbe_adv_rx_desc *rx_desc;
 		struct ixgbe_rx_buffer *rx_buffer;
 		struct sk_buff *skb;
-		struct xdp_buff xdp;
 		unsigned int size;
 
 		/* return some buffers to hardware, one@a time is too slow */
@@ -6444,6 +6446,11 @@ int ixgbe_setup_rx_resources(struct ixgbe_adapter *adapter,
 	rx_ring->next_to_clean = 0;
 	rx_ring->next_to_use = 0;
 
+	/* XDP RX-queue info */
+	if (xdp_rxq_info_reg(&rx_ring->xdp_rxq, adapter->netdev,
+			     rx_ring->queue_index) < 0)
+		goto err;
+
 	rx_ring->xdp_prog = adapter->xdp_prog;
 
 	return 0;
@@ -6541,6 +6548,7 @@ void ixgbe_free_rx_resources(struct ixgbe_ring *rx_ring)
 	ixgbe_clean_rx_ring(rx_ring);
 
 	rx_ring->xdp_prog = NULL;
+	xdp_rxq_info_unreg(&rx_ring->xdp_rxq);
 	vfree(rx_ring->rx_buffer_info);
 	rx_ring->rx_buffer_info = NULL;
 

[bpf-next V2 PATCH 05/14] xdp/qede: setup xdp_rxq_info and intro xdp_rxq_info_is_reg

[Jesper Dangaard Brouer]

The driver code qede_free_fp_array() depend on kfree() can be called
with a NULL pointer. This stems from the qede_alloc_fp_array()
function which either (kz)alloc memory for fp->txq or fp->rxq.
This also simplifies error handling code in case of memory allocation
failures, but xdp_rxq_info_unreg need to know the difference.

Introduce xdp_rxq_info_is_reg() to handle if a memory allocation fails
and detect this is the failure path by seeing that xdp_rxq_info was
not registred yet, which first happens after successful alloaction in
qede_init_fp().

Driver hook points for xdp_rxq_info:
 * reg  : qede_init_fp
 * unreg: qede_free_fp_array

Tested on actual hardware with samples/bpf program.

V2: Driver have no proper error path for failed XDP RX-queue info reg, as
qede_init_fp() is a void function.

Cc: everest-linux-l2@cavium.com
Cc: Ariel Elior <Ariel.Elior@cavium.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 drivers/net/ethernet/qlogic/qede/qede.h      |    2 ++
 drivers/net/ethernet/qlogic/qede/qede_fp.c   |    1 +
 drivers/net/ethernet/qlogic/qede/qede_main.c |   10 ++++++++++
 include/net/xdp.h                            |    1 +
 net/core/xdp.c                               |    6 ++++++
 5 files changed, 20 insertions(+)

diff --git a/drivers/net/ethernet/qlogic/qede/qede.h b/drivers/net/ethernet/qlogic/qede/qede.h
index a3a70ade411f..62f47736511b 100644
--- a/drivers/net/ethernet/qlogic/qede/qede.h
+++ b/drivers/net/ethernet/qlogic/qede/qede.h
@@ -40,6 +40,7 @@
 #include <linux/kernel.h>
 #include <linux/mutex.h>
 #include <linux/bpf.h>
+#include <net/xdp.h>
 #include <linux/qed/qede_rdma.h>
 #include <linux/io.h>
 #ifdef CONFIG_RFS_ACCEL
@@ -345,6 +346,7 @@ struct qede_rx_queue {
 	u64 xdp_no_pass;
 
 	void *handle;
+	struct xdp_rxq_info xdp_rxq;
 };
 
 union db_prod {
diff --git a/drivers/net/ethernet/qlogic/qede/qede_fp.c b/drivers/net/ethernet/qlogic/qede/qede_fp.c
index 48ec4c56cddf..dafc079ab6b9 100644
--- a/drivers/net/ethernet/qlogic/qede/qede_fp.c
+++ b/drivers/net/ethernet/qlogic/qede/qede_fp.c
@@ -1006,6 +1006,7 @@ static bool qede_rx_xdp(struct qede_dev *edev,
 	xdp.data = xdp.data_hard_start + *data_offset;
 	xdp_set_data_meta_invalid(&xdp);
 	xdp.data_end = xdp.data + *len;
+	xdp.rxq = &rxq->xdp_rxq;
 
 	/* Queues always have a full reset currently, so for the time
 	 * being until there's atomic program replace just mark read
diff --git a/drivers/net/ethernet/qlogic/qede/qede_main.c b/drivers/net/ethernet/qlogic/qede/qede_main.c
index 57332b3e5e64..24160f1fd0e5 100644
--- a/drivers/net/ethernet/qlogic/qede/qede_main.c
+++ b/drivers/net/ethernet/qlogic/qede/qede_main.c
@@ -762,6 +762,12 @@ static void qede_free_fp_array(struct qede_dev *edev)
 			fp = &edev->fp_array[i];
 
 			kfree(fp->sb_info);
+			/* Handle mem alloc failure case where qede_init_fp
+			 * didn't register xdp_rxq_info yet.
+			 * Implicit only (fp->type & QEDE_FASTPATH_RX)
+			 */
+			if (fp->rxq && xdp_rxq_info_is_reg(&fp->rxq->xdp_rxq))
+				xdp_rxq_info_unreg(&fp->rxq->xdp_rxq);
 			kfree(fp->rxq);
 			kfree(fp->xdp_tx);
 			kfree(fp->txq);
@@ -1498,6 +1504,10 @@ static void qede_init_fp(struct qede_dev *edev)
 			else
 				fp->rxq->data_direction = DMA_FROM_DEVICE;
 			fp->rxq->dev = &edev->pdev->dev;
+
+			/* Driver have no error path from here */
+			WARN_ON(xdp_rxq_info_reg(&fp->rxq->xdp_rxq, edev->ndev,
+						 fp->rxq->rxq_id) < 0);
 		}
 
 		if (fp->type & QEDE_FASTPATH_TX) {
diff --git a/include/net/xdp.h b/include/net/xdp.h
index 8c6e83293bba..9b29e06e4687 100644
--- a/include/net/xdp.h
+++ b/include/net/xdp.h
@@ -43,5 +43,6 @@ int xdp_rxq_info_reg(struct xdp_rxq_info *xdp_rxq,
 		     struct net_device *dev, u32 queue_index);
 void xdp_rxq_info_unreg(struct xdp_rxq_info *xdp_rxq);
 void xdp_rxq_info_unused(struct xdp_rxq_info *xdp_rxq);
+bool xdp_rxq_info_is_reg(struct xdp_rxq_info *xdp_rxq);
 
 #endif /* __LINUX_NET_XDP_H__ */
diff --git a/net/core/xdp.c b/net/core/xdp.c
index dde541b71aaa..5af17c44b92d 100644
--- a/net/core/xdp.c
+++ b/net/core/xdp.c
@@ -66,3 +66,9 @@ void xdp_rxq_info_unused(struct xdp_rxq_info *xdp_rxq)
 	xdp_rxq->reg_state = REG_STATE_UNUSED;
 }
 EXPORT_SYMBOL_GPL(xdp_rxq_info_unused);
+
+bool xdp_rxq_info_is_reg(struct xdp_rxq_info *xdp_rxq)
+{
+	return (xdp_rxq->reg_state == REG_STATE_REGISTERED);
+}
+EXPORT_SYMBOL_GPL(xdp_rxq_info_is_reg);

[bpf-next V2 PATCH 06/14] mlx4: setup xdp_rxq_info

[Jesper Dangaard Brouer]

Driver hook points for xdp_rxq_info:
 * reg  : mlx4_en_create_rx_ring
 * unreg: mlx4_en_destroy_rx_ring

Tested on actual hardware.

Cc: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 drivers/net/ethernet/mellanox/mlx4/en_netdev.c |    3 ++-
 drivers/net/ethernet/mellanox/mlx4/en_rx.c     |   13 ++++++++++---
 drivers/net/ethernet/mellanox/mlx4/mlx4_en.h   |    4 +++-
 3 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
index 99051a294fa6..0cfcf3089ae4 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -2172,8 +2172,9 @@ static int mlx4_en_alloc_resources(struct mlx4_en_priv *priv)
 
 		if (mlx4_en_create_rx_ring(priv, &priv->rx_ring[i],
 					   prof->rx_ring_size, priv->stride,
-					   node))
+					   node, i))
 			goto err;
+
 	}
 
 #ifdef CONFIG_RFS_ACCEL
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
index 85e28efcda33..48bbfc1ad391 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
@@ -262,7 +262,7 @@ void mlx4_en_set_num_rx_rings(struct mlx4_en_dev *mdev)
 
 int mlx4_en_create_rx_ring(struct mlx4_en_priv *priv,
 			   struct mlx4_en_rx_ring **pring,
-			   u32 size, u16 stride, int node)
+			   u32 size, u16 stride, int node, int queue_index)
 {
 	struct mlx4_en_dev *mdev = priv->mdev;
 	struct mlx4_en_rx_ring *ring;
@@ -286,6 +286,9 @@ int mlx4_en_create_rx_ring(struct mlx4_en_priv *priv,
 	ring->log_stride = ffs(ring->stride) - 1;
 	ring->buf_size = ring->size * ring->stride + TXBB_SIZE;
 
+	if (xdp_rxq_info_reg(&ring->xdp_rxq, priv->dev, queue_index) < 0)
+		goto err_ring;
+
 	tmp = size * roundup_pow_of_two(MLX4_EN_MAX_RX_FRAGS *
 					sizeof(struct mlx4_en_rx_alloc));
 	ring->rx_info = vzalloc_node(tmp, node);
@@ -293,7 +296,7 @@ int mlx4_en_create_rx_ring(struct mlx4_en_priv *priv,
 		ring->rx_info = vzalloc(tmp);
 		if (!ring->rx_info) {
 			err = -ENOMEM;
-			goto err_ring;
+			goto err_xdp_info;
 		}
 	}
 
@@ -317,6 +320,8 @@ int mlx4_en_create_rx_ring(struct mlx4_en_priv *priv,
 err_info:
 	vfree(ring->rx_info);
 	ring->rx_info = NULL;
+err_xdp_info:
+	xdp_rxq_info_unreg(&ring->xdp_rxq);
 err_ring:
 	kfree(ring);
 	*pring = NULL;
@@ -440,6 +445,7 @@ void mlx4_en_destroy_rx_ring(struct mlx4_en_priv *priv,
 					lockdep_is_held(&mdev->state_lock));
 	if (old_prog)
 		bpf_prog_put(old_prog);
+	xdp_rxq_info_unreg(&ring->xdp_rxq);
 	mlx4_free_hwq_res(mdev->dev, &ring->wqres, size * stride + TXBB_SIZE);
 	vfree(ring->rx_info);
 	ring->rx_info = NULL;
@@ -650,6 +656,7 @@ int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int bud
 	int cq_ring = cq->ring;
 	bool doorbell_pending;
 	struct mlx4_cqe *cqe;
+	struct xdp_buff xdp;
 	int polled = 0;
 	int index;
 
@@ -664,6 +671,7 @@ int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int bud
 	/* Protect accesses to: ring->xdp_prog, priv->mac_hash list */
 	rcu_read_lock();
 	xdp_prog = rcu_dereference(ring->xdp_prog);
+	xdp.rxq = &ring->xdp_rxq;
 	doorbell_pending = 0;
 
 	/* We assume a 1:1 mapping between CQEs and Rx descriptors, so Rx
@@ -748,7 +756,6 @@ int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int bud
 		 * read bytes but not past the end of the frag.
 		 */
 		if (xdp_prog) {
-			struct xdp_buff xdp;
 			dma_addr_t dma;
 			void *orig_data;
 			u32 act;
diff --git a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
index 2b72677eccd4..39f3f1b1ab0a 100644
--- a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
+++ b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
@@ -46,6 +46,7 @@
 #endif
 #include <linux/cpu_rmap.h>
 #include <linux/ptp_clock_kernel.h>
+#include <net/xdp.h>
 
 #include <linux/mlx4/device.h>
 #include <linux/mlx4/qp.h>
@@ -356,6 +357,7 @@ struct mlx4_en_rx_ring {
 	unsigned long dropped;
 	int hwtstamp_rx_filter;
 	cpumask_var_t affinity_mask;
+	struct xdp_rxq_info xdp_rxq;
 };
 
 struct mlx4_en_cq {
@@ -719,7 +721,7 @@ void mlx4_en_set_num_rx_rings(struct mlx4_en_dev *mdev);
 void mlx4_en_recover_from_oom(struct mlx4_en_priv *priv);
 int mlx4_en_create_rx_ring(struct mlx4_en_priv *priv,
 			   struct mlx4_en_rx_ring **pring,
-			   u32 size, u16 stride, int node);
+			   u32 size, u16 stride, int node, int queue_index);
 void mlx4_en_destroy_rx_ring(struct mlx4_en_priv *priv,
 			     struct mlx4_en_rx_ring **pring,
 			     u32 size, u16 stride);

[bpf-next V2 PATCH 07/14] bnxt_en: setup xdp_rxq_info

[Jesper Dangaard Brouer]

Driver hook points for xdp_rxq_info:
 * reg  : bnxt_alloc_rx_rings
 * unreg: bnxt_free_rx_rings

This driver should be updated to re-register when changing
allocation mode of RX rings.

Tested on actual hardware.

Cc: Andy Gospodarek <andy@greyhouse.net>
Cc: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c     |   10 ++++++++++
 drivers/net/ethernet/broadcom/bnxt/bnxt.h     |    2 ++
 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c |    1 +
 3 files changed, 13 insertions(+)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 1d865ae201db..e380f1a039ca 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -2247,6 +2247,9 @@ static void bnxt_free_rx_rings(struct bnxt *bp)
 		if (rxr->xdp_prog)
 			bpf_prog_put(rxr->xdp_prog);
 
+		if (xdp_rxq_info_is_reg(&rxr->xdp_rxq))
+			xdp_rxq_info_unreg(&rxr->xdp_rxq);
+
 		kfree(rxr->rx_tpa);
 		rxr->rx_tpa = NULL;
 
@@ -2280,6 +2283,10 @@ static int bnxt_alloc_rx_rings(struct bnxt *bp)
 
 		ring = &rxr->rx_ring_struct;
 
+		rc = xdp_rxq_info_reg(&rxr->xdp_rxq, bp->dev, i);
+		if (rc < 0)
+			return rc;
+
 		rc = bnxt_alloc_ring(bp, ring);
 		if (rc)
 			return rc;
@@ -2834,6 +2841,9 @@ void bnxt_set_ring_params(struct bnxt *bp)
 	bp->cp_ring_mask = bp->cp_bit - 1;
 }
 
+/* Changing allocation mode of RX rings.
+ * TODO: Update when extending xdp_rxq_info to support allocation modes.
+ */
 int bnxt_set_rx_skb_mode(struct bnxt *bp, bool page_mode)
 {
 	if (page_mode) {
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index 5359a1f0045f..2d268fc26f5e 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -23,6 +23,7 @@
 #include <net/devlink.h>
 #include <net/dst_metadata.h>
 #include <net/switchdev.h>
+#include <net/xdp.h>
 
 struct tx_bd {
 	__le32 tx_bd_len_flags_type;
@@ -664,6 +665,7 @@ struct bnxt_rx_ring_info {
 
 	struct bnxt_ring_struct	rx_ring_struct;
 	struct bnxt_ring_struct	rx_agg_ring_struct;
+	struct xdp_rxq_info	xdp_rxq;
 };
 
 struct bnxt_cp_ring_info {
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
index 261e5847557a..1389ab5e05df 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
@@ -96,6 +96,7 @@ bool bnxt_rx_xdp(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, u16 cons,
 	xdp.data = *data_ptr;
 	xdp_set_data_meta_invalid(&xdp);
 	xdp.data_end = *data_ptr + *len;
+	xdp.rxq = &rxr->xdp_rxq;
 	orig_data = xdp.data;
 	mapping = rx_buf->mapping - bp->rx_dma_offset;
 

[bpf-next V2 PATCH 08/14] nfp: setup xdp_rxq_info

[Jesper Dangaard Brouer]

Driver hook points for xdp_rxq_info:
 * reg  : nfp_net_rx_ring_alloc
 * unreg: nfp_net_rx_ring_free

In struct nfp_net_rx_ring moved member @size into a hole on 64-bit.
Thus, the size remaines the same after adding member @xdp_rxq.

Cc: oss-drivers@netronome.com
Cc: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: Simon Horman <simon.horman@netronome.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 drivers/net/ethernet/netronome/nfp/nfp_net.h       |    5 ++++-
 .../net/ethernet/netronome/nfp/nfp_net_common.c    |   10 ++++++++--
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net.h b/drivers/net/ethernet/netronome/nfp/nfp_net.h
index 3801c52098d5..0e564cfabe7e 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net.h
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net.h
@@ -47,6 +47,7 @@
 #include <linux/netdevice.h>
 #include <linux/pci.h>
 #include <linux/io-64-nonatomic-hi-lo.h>
+#include <net/xdp.h>
 
 #include "nfp_net_ctrl.h"
 
@@ -350,6 +351,7 @@ struct nfp_net_rx_buf {
  * @rxds:       Virtual address of FL/RX ring in host memory
  * @dma:        DMA address of the FL/RX ring
  * @size:       Size, in bytes, of the FL/RX ring (needed to free)
+ * @xdp_rxq:    RX-ring info avail for XDP
  */
 struct nfp_net_rx_ring {
 	struct nfp_net_r_vector *r_vec;
@@ -361,13 +363,14 @@ struct nfp_net_rx_ring {
 	u32 idx;
 
 	int fl_qcidx;
+	unsigned int size;
 	u8 __iomem *qcp_fl;
 
 	struct nfp_net_rx_buf *rxbufs;
 	struct nfp_net_rx_desc *rxds;
 
 	dma_addr_t dma;
-	unsigned int size;
+	struct xdp_rxq_info xdp_rxq;
 } ____cacheline_aligned;
 
 /**
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index 0add4870ce2e..45b8cae937be 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -1608,11 +1608,13 @@ static int nfp_net_rx(struct nfp_net_rx_ring *rx_ring, int budget)
 	unsigned int true_bufsz;
 	struct sk_buff *skb;
 	int pkts_polled = 0;
+	struct xdp_buff xdp;
 	int idx;
 
 	rcu_read_lock();
 	xdp_prog = READ_ONCE(dp->xdp_prog);
 	true_bufsz = xdp_prog ? PAGE_SIZE : dp->fl_bufsz;
+	xdp.rxq = &rx_ring->xdp_rxq;
 	tx_ring = r_vec->xdp_ring;
 
 	while (pkts_polled < budget) {
@@ -1703,7 +1705,6 @@ static int nfp_net_rx(struct nfp_net_rx_ring *rx_ring, int budget)
 				  dp->bpf_offload_xdp) && !meta.portid) {
 			void *orig_data = rxbuf->frag + pkt_off;
 			unsigned int dma_off;
-			struct xdp_buff xdp;
 			int act;
 
 			xdp.data_hard_start = rxbuf->frag + NFP_NET_RX_BUF_HEADROOM;
@@ -2252,6 +2253,7 @@ static void nfp_net_rx_ring_free(struct nfp_net_rx_ring *rx_ring)
 	struct nfp_net_r_vector *r_vec = rx_ring->r_vec;
 	struct nfp_net_dp *dp = &r_vec->nfp_net->dp;
 
+	xdp_rxq_info_unreg(&rx_ring->xdp_rxq);
 	kfree(rx_ring->rxbufs);
 
 	if (rx_ring->rxds)
@@ -2275,7 +2277,11 @@ static void nfp_net_rx_ring_free(struct nfp_net_rx_ring *rx_ring)
 static int
 nfp_net_rx_ring_alloc(struct nfp_net_dp *dp, struct nfp_net_rx_ring *rx_ring)
 {
-	int sz;
+	int sz, err;
+
+	err = xdp_rxq_info_reg(&rx_ring->xdp_rxq, dp->netdev, rx_ring->idx);
+	if (err < 0)
+		return err;
 
 	rx_ring->cnt = dp->rxd_cnt;
 	rx_ring->size = sizeof(*rx_ring->rxds) * rx_ring->cnt;

[bpf-next V2 PATCH 09/14] thunderx: setup xdp_rxq_info

[Jesper Dangaard Brouer]

This driver uses a bool scheme for "enable"/"disable" when setting up
different resources.  Thus, the hook points for xdp_rxq_info is done
in the same function call nicvf_rcv_queue_config().  This is activated
through enable/disable via nicvf_config_data_transfer(), which is tied
into nicvf_stop()/nicvf_open().

Extending driver packet handler call-path nicvf_rcv_pkt_handler() with
a pointer to the given struct rcv_queue, in-order to access the
xdp_rxq_info data area (in nicvf_xdp_rx()).

V2: Driver have no proper error path for failed XDP RX-queue info reg,
as nicvf_rcv_queue_config is a void function.

Cc: linux-arm-kernel@lists.infradead.org
Cc: Sunil Goutham <sgoutham@cavium.com>
Cc: Robert Richter <rric@kernel.org>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 drivers/net/ethernet/cavium/thunder/nicvf_main.c   |   11 +++++++----
 drivers/net/ethernet/cavium/thunder/nicvf_queues.c |    4 ++++
 drivers/net/ethernet/cavium/thunder/nicvf_queues.h |    2 ++
 3 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_main.c b/drivers/net/ethernet/cavium/thunder/nicvf_main.c
index 52b3a6044f85..21618d0d694f 100644
--- a/drivers/net/ethernet/cavium/thunder/nicvf_main.c
+++ b/drivers/net/ethernet/cavium/thunder/nicvf_main.c
@@ -521,7 +521,7 @@ static void nicvf_unmap_page(struct nicvf *nic, struct page *page, u64 dma_addr)
 
 static inline bool nicvf_xdp_rx(struct nicvf *nic, struct bpf_prog *prog,
 				struct cqe_rx_t *cqe_rx, struct snd_queue *sq,
-				struct sk_buff **skb)
+				struct rcv_queue *rq, struct sk_buff **skb)
 {
 	struct xdp_buff xdp;
 	struct page *page;
@@ -545,6 +545,7 @@ static inline bool nicvf_xdp_rx(struct nicvf *nic, struct bpf_prog *prog,
 	xdp.data = (void *)cpu_addr;
 	xdp_set_data_meta_invalid(&xdp);
 	xdp.data_end = xdp.data + len;
+	xdp.rxq = &rq->xdp_rxq;
 	orig_data = xdp.data;
 
 	rcu_read_lock();
@@ -698,7 +699,8 @@ static inline void nicvf_set_rxhash(struct net_device *netdev,
 
 static void nicvf_rcv_pkt_handler(struct net_device *netdev,
 				  struct napi_struct *napi,
-				  struct cqe_rx_t *cqe_rx, struct snd_queue *sq)
+				  struct cqe_rx_t *cqe_rx,
+				  struct snd_queue *sq, struct rcv_queue *rq)
 {
 	struct sk_buff *skb = NULL;
 	struct nicvf *nic = netdev_priv(netdev);
@@ -724,7 +726,7 @@ static void nicvf_rcv_pkt_handler(struct net_device *netdev,
 	/* For XDP, ignore pkts spanning multiple pages */
 	if (nic->xdp_prog && (cqe_rx->rb_cnt == 1)) {
 		/* Packet consumed by XDP */
-		if (nicvf_xdp_rx(snic, nic->xdp_prog, cqe_rx, sq, &skb))
+		if (nicvf_xdp_rx(snic, nic->xdp_prog, cqe_rx, sq, rq, &skb))
 			return;
 	} else {
 		skb = nicvf_get_rcv_skb(snic, cqe_rx,
@@ -781,6 +783,7 @@ static int nicvf_cq_intr_handler(struct net_device *netdev, u8 cq_idx,
 	struct cqe_rx_t *cq_desc;
 	struct netdev_queue *txq;
 	struct snd_queue *sq = &qs->sq[cq_idx];
+	struct rcv_queue *rq = &qs->rq[cq_idx];
 	unsigned int tx_pkts = 0, tx_bytes = 0, txq_idx;
 
 	spin_lock_bh(&cq->lock);
@@ -811,7 +814,7 @@ static int nicvf_cq_intr_handler(struct net_device *netdev, u8 cq_idx,
 
 		switch (cq_desc->cqe_type) {
 		case CQE_TYPE_RX:
-			nicvf_rcv_pkt_handler(netdev, napi, cq_desc, sq);
+			nicvf_rcv_pkt_handler(netdev, napi, cq_desc, sq, rq);
 			work_done++;
 		break;
 		case CQE_TYPE_SEND:
diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_queues.c b/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
index f38ea349aa00..14e62c6ac342 100644
--- a/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
+++ b/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
@@ -760,6 +760,7 @@ static void nicvf_rcv_queue_config(struct nicvf *nic, struct queue_set *qs,
 
 	if (!rq->enable) {
 		nicvf_reclaim_rcv_queue(nic, qs, qidx);
+		xdp_rxq_info_unreg(&rq->xdp_rxq);
 		return;
 	}
 
@@ -772,6 +773,9 @@ static void nicvf_rcv_queue_config(struct nicvf *nic, struct queue_set *qs,
 	/* all writes of RBDR data to be loaded into L2 Cache as well*/
 	rq->caching = 1;
 
+	/* Driver have no proper error path for failed XDP RX-queue info reg */
+	WARN_ON(xdp_rxq_info_reg(&rq->xdp_rxq, nic->netdev, qidx) < 0);
+
 	/* Send a mailbox msg to PF to config RQ */
 	mbx.rq.msg = NIC_MBOX_MSG_RQ_CFG;
 	mbx.rq.qs_num = qs->vnic_id;
diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_queues.h b/drivers/net/ethernet/cavium/thunder/nicvf_queues.h
index 178ab6e8e3c5..7d1e4e2aaad0 100644
--- a/drivers/net/ethernet/cavium/thunder/nicvf_queues.h
+++ b/drivers/net/ethernet/cavium/thunder/nicvf_queues.h
@@ -12,6 +12,7 @@
 #include <linux/netdevice.h>
 #include <linux/iommu.h>
 #include <linux/bpf.h>
+#include <net/xdp.h>
 #include "q_struct.h"
 
 #define MAX_QUEUE_SET			128
@@ -255,6 +256,7 @@ struct rcv_queue {
 	u8		start_qs_rbdr_idx; /* RBDR idx in the above QS */
 	u8		caching;
 	struct		rx_tx_queue_stats stats;
+	struct xdp_rxq_info xdp_rxq;
 } ____cacheline_aligned_in_smp;
 
 struct cmp_queue {

[bpf-next V2 PATCH 09/14] thunderx: setup xdp_rxq_info

[Jesper Dangaard Brouer]

This driver uses a bool scheme for "enable"/"disable" when setting up
different resources.  Thus, the hook points for xdp_rxq_info is done
in the same function call nicvf_rcv_queue_config().  This is activated
through enable/disable via nicvf_config_data_transfer(), which is tied
into nicvf_stop()/nicvf_open().

Extending driver packet handler call-path nicvf_rcv_pkt_handler() with
a pointer to the given struct rcv_queue, in-order to access the
xdp_rxq_info data area (in nicvf_xdp_rx()).

V2: Driver have no proper error path for failed XDP RX-queue info reg,
as nicvf_rcv_queue_config is a void function.

Cc: linux-arm-kernel at lists.infradead.org
Cc: Sunil Goutham <sgoutham@cavium.com>
Cc: Robert Richter <rric@kernel.org>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 drivers/net/ethernet/cavium/thunder/nicvf_main.c   |   11 +++++++----
 drivers/net/ethernet/cavium/thunder/nicvf_queues.c |    4 ++++
 drivers/net/ethernet/cavium/thunder/nicvf_queues.h |    2 ++
 3 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_main.c b/drivers/net/ethernet/cavium/thunder/nicvf_main.c
index 52b3a6044f85..21618d0d694f 100644
--- a/drivers/net/ethernet/cavium/thunder/nicvf_main.c
+++ b/drivers/net/ethernet/cavium/thunder/nicvf_main.c
@@ -521,7 +521,7 @@ static void nicvf_unmap_page(struct nicvf *nic, struct page *page, u64 dma_addr)
 
 static inline bool nicvf_xdp_rx(struct nicvf *nic, struct bpf_prog *prog,
 				struct cqe_rx_t *cqe_rx, struct snd_queue *sq,
-				struct sk_buff **skb)
+				struct rcv_queue *rq, struct sk_buff **skb)
 {
 	struct xdp_buff xdp;
 	struct page *page;
@@ -545,6 +545,7 @@ static inline bool nicvf_xdp_rx(struct nicvf *nic, struct bpf_prog *prog,
 	xdp.data = (void *)cpu_addr;
 	xdp_set_data_meta_invalid(&xdp);
 	xdp.data_end = xdp.data + len;
+	xdp.rxq = &rq->xdp_rxq;
 	orig_data = xdp.data;
 
 	rcu_read_lock();
@@ -698,7 +699,8 @@ static inline void nicvf_set_rxhash(struct net_device *netdev,
 
 static void nicvf_rcv_pkt_handler(struct net_device *netdev,
 				  struct napi_struct *napi,
-				  struct cqe_rx_t *cqe_rx, struct snd_queue *sq)
+				  struct cqe_rx_t *cqe_rx,
+				  struct snd_queue *sq, struct rcv_queue *rq)
 {
 	struct sk_buff *skb = NULL;
 	struct nicvf *nic = netdev_priv(netdev);
@@ -724,7 +726,7 @@ static void nicvf_rcv_pkt_handler(struct net_device *netdev,
 	/* For XDP, ignore pkts spanning multiple pages */
 	if (nic->xdp_prog && (cqe_rx->rb_cnt == 1)) {
 		/* Packet consumed by XDP */
-		if (nicvf_xdp_rx(snic, nic->xdp_prog, cqe_rx, sq, &skb))
+		if (nicvf_xdp_rx(snic, nic->xdp_prog, cqe_rx, sq, rq, &skb))
 			return;
 	} else {
 		skb = nicvf_get_rcv_skb(snic, cqe_rx,
@@ -781,6 +783,7 @@ static int nicvf_cq_intr_handler(struct net_device *netdev, u8 cq_idx,
 	struct cqe_rx_t *cq_desc;
 	struct netdev_queue *txq;
 	struct snd_queue *sq = &qs->sq[cq_idx];
+	struct rcv_queue *rq = &qs->rq[cq_idx];
 	unsigned int tx_pkts = 0, tx_bytes = 0, txq_idx;
 
 	spin_lock_bh(&cq->lock);
@@ -811,7 +814,7 @@ static int nicvf_cq_intr_handler(struct net_device *netdev, u8 cq_idx,
 
 		switch (cq_desc->cqe_type) {
 		case CQE_TYPE_RX:
-			nicvf_rcv_pkt_handler(netdev, napi, cq_desc, sq);
+			nicvf_rcv_pkt_handler(netdev, napi, cq_desc, sq, rq);
 			work_done++;
 		break;
 		case CQE_TYPE_SEND:
diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_queues.c b/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
index f38ea349aa00..14e62c6ac342 100644
--- a/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
+++ b/drivers/net/ethernet/cavium/thunder/nicvf_queues.c
@@ -760,6 +760,7 @@ static void nicvf_rcv_queue_config(struct nicvf *nic, struct queue_set *qs,
 
 	if (!rq->enable) {
 		nicvf_reclaim_rcv_queue(nic, qs, qidx);
+		xdp_rxq_info_unreg(&rq->xdp_rxq);
 		return;
 	}
 
@@ -772,6 +773,9 @@ static void nicvf_rcv_queue_config(struct nicvf *nic, struct queue_set *qs,
 	/* all writes of RBDR data to be loaded into L2 Cache as well*/
 	rq->caching = 1;
 
+	/* Driver have no proper error path for failed XDP RX-queue info reg */
+	WARN_ON(xdp_rxq_info_reg(&rq->xdp_rxq, nic->netdev, qidx) < 0);
+
 	/* Send a mailbox msg to PF to config RQ */
 	mbx.rq.msg = NIC_MBOX_MSG_RQ_CFG;
 	mbx.rq.qs_num = qs->vnic_id;
diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_queues.h b/drivers/net/ethernet/cavium/thunder/nicvf_queues.h
index 178ab6e8e3c5..7d1e4e2aaad0 100644
--- a/drivers/net/ethernet/cavium/thunder/nicvf_queues.h
+++ b/drivers/net/ethernet/cavium/thunder/nicvf_queues.h
@@ -12,6 +12,7 @@
 #include <linux/netdevice.h>
 #include <linux/iommu.h>
 #include <linux/bpf.h>
+#include <net/xdp.h>
 #include "q_struct.h"
 
 #define MAX_QUEUE_SET			128
@@ -255,6 +256,7 @@ struct rcv_queue {
 	u8		start_qs_rbdr_idx; /* RBDR idx in the above QS */
 	u8		caching;
 	struct		rx_tx_queue_stats stats;
+	struct xdp_rxq_info xdp_rxq;
 } ____cacheline_aligned_in_smp;
 
 struct cmp_queue {

[bpf-next V2 PATCH 10/14] tun: setup xdp_rxq_info

[Jesper Dangaard Brouer]

Driver hook points for xdp_rxq_info:
 * reg  : tun_attach
 * unreg: __tun_detach

I've done some manual testing of this tun driver, but I would
appriciate good review and someone else running their use-case tests,
as I'm not 100% sure I understand the tfile->detached semantics.

V2: Removed the skb_array_cleanup() call from V1 by request from Jason Wang.

Cc: Jason Wang <jasowang@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 drivers/net/tun.c |   24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index e367d6310353..e7c5f4b2a9a6 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -180,6 +180,7 @@ struct tun_file {
 	struct list_head next;
 	struct tun_struct *detached;
 	struct skb_array tx_array;
+	struct xdp_rxq_info xdp_rxq;
 };
 
 struct tun_flow_entry {
@@ -687,8 +688,10 @@ static void __tun_detach(struct tun_file *tfile, bool clean)
 			    tun->dev->reg_state == NETREG_REGISTERED)
 				unregister_netdevice(tun->dev);
 		}
-		if (tun)
+		if (tun) {
 			skb_array_cleanup(&tfile->tx_array);
+			xdp_rxq_info_unreg(&tfile->xdp_rxq);
+		}
 		sock_put(&tfile->sk);
 	}
 }
@@ -728,11 +731,13 @@ static void tun_detach_all(struct net_device *dev)
 		tun_napi_del(tun, tfile);
 		/* Drop read queue */
 		tun_queue_purge(tfile);
+		xdp_rxq_info_unreg(&tfile->xdp_rxq);
 		sock_put(&tfile->sk);
 	}
 	list_for_each_entry_safe(tfile, tmp, &tun->disabled, next) {
 		tun_enable_queue(tfile);
 		tun_queue_purge(tfile);
+		xdp_rxq_info_unreg(&tfile->xdp_rxq);
 		sock_put(&tfile->sk);
 	}
 	BUG_ON(tun->numdisabled != 0);
@@ -784,6 +789,22 @@ static int tun_attach(struct tun_struct *tun, struct file *file,
 
 	tfile->queue_index = tun->numqueues;
 	tfile->socket.sk->sk_shutdown &= ~RCV_SHUTDOWN;
+
+	if (tfile->detached) {
+		/* Re-attach detached tfile, updating XDP queue_index */
+		WARN_ON(!xdp_rxq_info_is_reg(&tfile->xdp_rxq));
+
+		if (tfile->xdp_rxq.queue_index    != tfile->queue_index)
+			tfile->xdp_rxq.queue_index = tfile->queue_index;
+	} else {
+		/* Setup XDP RX-queue info, for new tfile getting attached */
+		err = xdp_rxq_info_reg(&tfile->xdp_rxq,
+				       tun->dev, tfile->queue_index);
+		if (err < 0)
+			goto out;
+		err = 0;
+	}
+
 	rcu_assign_pointer(tfile->tun, tun);
 	rcu_assign_pointer(tun->tfiles[tun->numqueues], tfile);
 	tun->numqueues++;
@@ -1508,6 +1529,7 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun,
 		xdp.data = buf + pad;
 		xdp_set_data_meta_invalid(&xdp);
 		xdp.data_end = xdp.data + len;
+		xdp.rxq = &tfile->xdp_rxq;
 		orig_data = xdp.data;
 		act = bpf_prog_run_xdp(xdp_prog, &xdp);
 

[bpf-next V2 PATCH 11/14] virtio_net: setup xdp_rxq_info

[Jesper Dangaard Brouer]

The virtio_net driver doesn't dynamically change the RX-ring queue
layout and backing pages, but instead reject XDP setup if all the
conditions for XDP is not meet.  Thus, the xdp_rxq_info also remains
fairly static.  This allow us to simply add the reg/unreg to
net_device open/close functions.

Driver hook points for xdp_rxq_info:
 * reg  : virtnet_open
 * unreg: virtnet_close

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 drivers/net/virtio_net.c |   12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 6fb7b658a6cc..6d45d687ec6a 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -31,6 +31,7 @@
 #include <linux/average.h>
 #include <linux/filter.h>
 #include <net/route.h>
+#include <net/xdp.h>
 
 static int napi_weight = NAPI_POLL_WEIGHT;
 module_param(napi_weight, int, 0444);
@@ -115,6 +116,8 @@ struct receive_queue {
 
 	/* Name of this receive queue: input.$index */
 	char name[40];
+
+	struct xdp_rxq_info xdp_rxq;
 };
 
 struct virtnet_info {
@@ -559,6 +562,7 @@ static struct sk_buff *receive_small(struct net_device *dev,
 		xdp.data = xdp.data_hard_start + xdp_headroom;
 		xdp_set_data_meta_invalid(&xdp);
 		xdp.data_end = xdp.data + len;
+		xdp.rxq = &rq->xdp_rxq;
 		orig_data = xdp.data;
 		act = bpf_prog_run_xdp(xdp_prog, &xdp);
 
@@ -1225,13 +1229,18 @@ static int virtnet_poll(struct napi_struct *napi, int budget)
 static int virtnet_open(struct net_device *dev)
 {
 	struct virtnet_info *vi = netdev_priv(dev);
-	int i;
+	int i, err;
 
 	for (i = 0; i < vi->max_queue_pairs; i++) {
 		if (i < vi->curr_queue_pairs)
 			/* Make sure we have some buffers: if oom use wq. */
 			if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
 				schedule_delayed_work(&vi->refill, 0);
+
+		err = xdp_rxq_info_reg(&vi->rq[i].xdp_rxq, dev, i);
+		if (err < 0)
+			return err;
+
 		virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
 		virtnet_napi_tx_enable(vi, vi->sq[i].vq, &vi->sq[i].napi);
 	}
@@ -1560,6 +1569,7 @@ static int virtnet_close(struct net_device *dev)
 	cancel_delayed_work_sync(&vi->refill);
 
 	for (i = 0; i < vi->max_queue_pairs; i++) {
+		xdp_rxq_info_unreg(&vi->rq[i].xdp_rxq);
 		napi_disable(&vi->rq[i].napi);
 		virtnet_napi_tx_disable(&vi->sq[i].napi);
 	}

[bpf-next V2 PATCH 11/14] virtio_net: setup xdp_rxq_info

[Jesper Dangaard Brouer]

The virtio_net driver doesn't dynamically change the RX-ring queue
layout and backing pages, but instead reject XDP setup if all the
conditions for XDP is not meet.  Thus, the xdp_rxq_info also remains
fairly static.  This allow us to simply add the reg/unreg to
net_device open/close functions.

Driver hook points for xdp_rxq_info:
 * reg  : virtnet_open
 * unreg: virtnet_close

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 drivers/net/virtio_net.c |   12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 6fb7b658a6cc..6d45d687ec6a 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -31,6 +31,7 @@
 #include <linux/average.h>
 #include <linux/filter.h>
 #include <net/route.h>
+#include <net/xdp.h>
 
 static int napi_weight = NAPI_POLL_WEIGHT;
 module_param(napi_weight, int, 0444);
@@ -115,6 +116,8 @@ struct receive_queue {
 
 	/* Name of this receive queue: input.$index */
 	char name[40];
+
+	struct xdp_rxq_info xdp_rxq;
 };
 
 struct virtnet_info {
@@ -559,6 +562,7 @@ static struct sk_buff *receive_small(struct net_device *dev,
 		xdp.data = xdp.data_hard_start + xdp_headroom;
 		xdp_set_data_meta_invalid(&xdp);
 		xdp.data_end = xdp.data + len;
+		xdp.rxq = &rq->xdp_rxq;
 		orig_data = xdp.data;
 		act = bpf_prog_run_xdp(xdp_prog, &xdp);
 
@@ -1225,13 +1229,18 @@ static int virtnet_poll(struct napi_struct *napi, int budget)
 static int virtnet_open(struct net_device *dev)
 {
 	struct virtnet_info *vi = netdev_priv(dev);
-	int i;
+	int i, err;
 
 	for (i = 0; i < vi->max_queue_pairs; i++) {
 		if (i < vi->curr_queue_pairs)
 			/* Make sure we have some buffers: if oom use wq. */
 			if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
 				schedule_delayed_work(&vi->refill, 0);
+
+		err = xdp_rxq_info_reg(&vi->rq[i].xdp_rxq, dev, i);
+		if (err < 0)
+			return err;
+
 		virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
 		virtnet_napi_tx_enable(vi, vi->sq[i].vq, &vi->sq[i].napi);
 	}
@@ -1560,6 +1569,7 @@ static int virtnet_close(struct net_device *dev)
 	cancel_delayed_work_sync(&vi->refill);
 
 	for (i = 0; i < vi->max_queue_pairs; i++) {
+		xdp_rxq_info_unreg(&vi->rq[i].xdp_rxq);
 		napi_disable(&vi->rq[i].napi);
 		virtnet_napi_tx_disable(&vi->sq[i].napi);
 	}

[bpf-next V2 PATCH 12/14] xdp: generic XDP handling of xdp_rxq_info

[Jesper Dangaard Brouer]

Hook points for xdp_rxq_info:
 * reg  : netif_alloc_rx_queues
 * unreg: netif_free_rx_queues

The net_device have some members (num_rx_queues + real_num_rx_queues)
and data-area (dev->_rx with struct netdev_rx_queue's) that were
primarily used for exporting information about RPS (CONFIG_RPS) queues
to sysfs (CONFIG_SYSFS).

For generic XDP extend struct netdev_rx_queue with the xdp_rxq_info,
and remove some of the CONFIG_SYSFS ifdefs.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 include/linux/netdevice.h |    2 +
 net/core/dev.c            |   69 ++++++++++++++++++++++++++++++++++++++-------
 2 files changed, 61 insertions(+), 10 deletions(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index cc4ce7456e38..43595b037872 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -44,6 +44,7 @@
 #include <net/dcbnl.h>
 #endif
 #include <net/netprio_cgroup.h>
+#include <net/xdp.h>
 
 #include <linux/netdev_features.h>
 #include <linux/neighbour.h>
@@ -686,6 +687,7 @@ struct netdev_rx_queue {
 #endif
 	struct kobject			kobj;
 	struct net_device		*dev;
+	struct xdp_rxq_info		xdp_rxq;
 } ____cacheline_aligned_in_smp;
 
 /*
diff --git a/net/core/dev.c b/net/core/dev.c
index b0eee49a2489..24d7bbdf3758 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3889,9 +3889,33 @@ static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
 	return NET_RX_DROP;
 }
 
+static struct netdev_rx_queue *netif_get_rxqueue(struct sk_buff *skb)
+{
+	struct net_device *dev = skb->dev;
+	struct netdev_rx_queue *rxqueue;
+
+	rxqueue = dev->_rx;
+
+	if (skb_rx_queue_recorded(skb)) {
+		u16 index = skb_get_rx_queue(skb);
+
+		if (unlikely(index >= dev->real_num_rx_queues)) {
+			WARN_ONCE(dev->real_num_rx_queues > 1,
+				  "%s received packet on queue %u, but number "
+				  "of RX queues is %u\n",
+				  dev->name, index, dev->real_num_rx_queues);
+
+			return rxqueue; /* Return first rxqueue */
+		}
+		rxqueue += index;
+	}
+	return rxqueue;
+}
+
 static u32 netif_receive_generic_xdp(struct sk_buff *skb,
 				     struct bpf_prog *xdp_prog)
 {
+	struct netdev_rx_queue *rxqueue;
 	u32 metalen, act = XDP_DROP;
 	struct xdp_buff xdp;
 	void *orig_data;
@@ -3935,6 +3959,9 @@ static u32 netif_receive_generic_xdp(struct sk_buff *skb,
 	xdp.data_hard_start = skb->data - skb_headroom(skb);
 	orig_data = xdp.data;
 
+	rxqueue = netif_get_rxqueue(skb);
+	xdp.rxq = &rxqueue->xdp_rxq;
+
 	act = bpf_prog_run_xdp(xdp_prog, &xdp);
 
 	off = xdp.data - orig_data;
@@ -7557,12 +7584,12 @@ void netif_stacked_transfer_operstate(const struct net_device *rootdev,
 }
 EXPORT_SYMBOL(netif_stacked_transfer_operstate);
 
-#ifdef CONFIG_SYSFS
 static int netif_alloc_rx_queues(struct net_device *dev)
 {
 	unsigned int i, count = dev->num_rx_queues;
 	struct netdev_rx_queue *rx;
 	size_t sz = count * sizeof(*rx);
+	int err = 0;
 
 	BUG_ON(count < 1);
 
@@ -7572,11 +7599,39 @@ static int netif_alloc_rx_queues(struct net_device *dev)
 
 	dev->_rx = rx;
 
-	for (i = 0; i < count; i++)
+	for (i = 0; i < count; i++) {
 		rx[i].dev = dev;
+
+		/* XDP RX-queue setup */
+		err = xdp_rxq_info_reg(&rx[i].xdp_rxq, dev, i);
+		if (err < 0)
+			goto err_rxq_info;
+	}
 	return 0;
+
+err_rxq_info:
+	/* Rollback successful reg's and free other resources */
+	while (i--)
+		xdp_rxq_info_unreg(&rx[i].xdp_rxq);
+	kfree(dev->_rx);
+	dev->_rx = NULL;
+	return err;
+}
+
+static void netif_free_rx_queues(struct net_device *dev)
+{
+	unsigned int i, count = dev->num_rx_queues;
+	struct netdev_rx_queue *rx;
+
+	/* netif_alloc_rx_queues alloc failed, resources have been unreg'ed */
+	if (!dev->_rx)
+		return;
+
+	rx = dev->_rx;
+
+	for (i = 0; i < count; i++)
+		xdp_rxq_info_unreg(&rx[i].xdp_rxq);
 }
-#endif
 
 static void netdev_init_one_queue(struct net_device *dev,
 				  struct netdev_queue *queue, void *_unused)
@@ -8137,12 +8192,10 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
 		return NULL;
 	}
 
-#ifdef CONFIG_SYSFS
 	if (rxqs < 1) {
 		pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
 		return NULL;
 	}
-#endif
 
 	alloc_size = sizeof(struct net_device);
 	if (sizeof_priv) {
@@ -8199,12 +8252,10 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
 	if (netif_alloc_netdev_queues(dev))
 		goto free_all;
 
-#ifdef CONFIG_SYSFS
 	dev->num_rx_queues = rxqs;
 	dev->real_num_rx_queues = rxqs;
 	if (netif_alloc_rx_queues(dev))
 		goto free_all;
-#endif
 
 	strcpy(dev->name, name);
 	dev->name_assign_type = name_assign_type;
@@ -8243,9 +8294,7 @@ void free_netdev(struct net_device *dev)
 
 	might_sleep();
 	netif_free_tx_queues(dev);
-#ifdef CONFIG_SYSFS
-	kvfree(dev->_rx);
-#endif
+	netif_free_rx_queues(dev);
 
 	kfree(rcu_dereference_protected(dev->ingress_queue, 1));
 

[bpf-next V2 PATCH 13/14] bpf: finally expose xdp_rxq_info to XDP bpf-programs

[Jesper Dangaard Brouer]

Now all XDP driver have been updated to setup xdp_rxq_info and assign
this to xdp_buff->rxq.  Thus, it is now safe to enable access to some
of the xdp_rxq_info struct members.

This patch extend xdp_md and expose UAPI to userspace for
ingress_ifindex and rx_queue_index.  Access happens via bpf
instruction rewrite, that load data directly from struct xdp_rxq_info.

* ingress_ifindex map to xdp_rxq_info->dev->ifindex
* rx_queue_index  map to xdp_rxq_info->queue_index

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 include/uapi/linux/bpf.h |    3 +++
 net/core/filter.c        |   19 +++++++++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 69eabfcb9bdb..a6000a95d40e 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -899,6 +899,9 @@ struct xdp_md {
 	__u32 data;
 	__u32 data_end;
 	__u32 data_meta;
+	/* Below access go though struct xdp_rxq_info */
+	__u32 ingress_ifindex; /* rxq->dev->ifindex */
+	__u32 rx_queue_index;  /* rxq->queue_index  */
 };
 
 enum sk_action {
diff --git a/net/core/filter.c b/net/core/filter.c
index 130b842c3a15..acdb94c0e97f 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -4304,6 +4304,25 @@ static u32 xdp_convert_ctx_access(enum bpf_access_type type,
 				      si->dst_reg, si->src_reg,
 				      offsetof(struct xdp_buff, data_end));
 		break;
+	case offsetof(struct xdp_md, ingress_ifindex):
+		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
+				      si->dst_reg, si->src_reg,
+				      offsetof(struct xdp_buff, rxq));
+		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_rxq_info, dev),
+				      si->dst_reg, si->dst_reg,
+				      offsetof(struct xdp_rxq_info, dev));
+		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
+				      bpf_target_off(struct net_device,
+						     ifindex, 4, target_size));
+		break;
+	case offsetof(struct xdp_md, rx_queue_index):
+		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
+				      si->dst_reg, si->src_reg,
+				      offsetof(struct xdp_buff, rxq));
+		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
+				      bpf_target_off(struct xdp_rxq_info,
+						queue_index, 4, target_size));
+		break;
 	}
 
 	return insn - insn_buf;

[bpf-next V2 PATCH 14/14] samples/bpf: program demonstrating access to xdp_rxq_info

[Jesper Dangaard Brouer]

This sample program can be used for monitoring and reporting how many
packets per sec (pps) are received per NIC RX queue index and which
CPU processed the packet. In itself it is a useful tool for quickly
identifying RSS imbalance issues, see below.

The default XDP action is XDP_PASS in-order to provide a monitor
mode. For benchmarking purposes it is possible to specify other XDP
actions on the cmdline --action.

Output below shows an imbalance RSS case where most RXQ's deliver to
CPU-0 while CPU-2 only get packets from a single RXQ.  Looking at
things from a CPU level the two CPUs are processing approx the same
amount, BUT looking at the rx_queue_index levels it is clear that
RXQ-2 receive much better service, than other RXQs which all share CPU-0.

Running XDP on dev:i40e1 (ifindex:3) action:XDP_PASS
XDP stats       CPU     pps         issue-pps
XDP-RX CPU      0       900,473     0
XDP-RX CPU      2       906,921     0
XDP-RX CPU      total   1,807,395

RXQ stats       RXQ:CPU pps         issue-pps
rx_queue_index    0:0   180,098     0
rx_queue_index    0:sum 180,098
rx_queue_index    1:0   180,098     0
rx_queue_index    1:sum 180,098
rx_queue_index    2:2   906,921     0
rx_queue_index    2:sum 906,921
rx_queue_index    3:0   180,098     0
rx_queue_index    3:sum 180,098
rx_queue_index    4:0   180,082     0
rx_queue_index    4:sum 180,082
rx_queue_index    5:0   180,093     0
rx_queue_index    5:sum 180,093

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 samples/bpf/Makefile            |    4 
 samples/bpf/xdp_rxq_info_kern.c |   96 +++++++
 samples/bpf/xdp_rxq_info_user.c |  532 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 632 insertions(+)
 create mode 100644 samples/bpf/xdp_rxq_info_kern.c
 create mode 100644 samples/bpf/xdp_rxq_info_user.c

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 4fb944a7ecf8..3ff7a05bea9a 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -41,6 +41,7 @@ hostprogs-y += xdp_redirect
 hostprogs-y += xdp_redirect_map
 hostprogs-y += xdp_redirect_cpu
 hostprogs-y += xdp_monitor
+hostprogs-y += xdp_rxq_info
 hostprogs-y += syscall_tp
 
 # Libbpf dependencies
@@ -90,6 +91,7 @@ xdp_redirect-objs := bpf_load.o $(LIBBPF) xdp_redirect_user.o
 xdp_redirect_map-objs := bpf_load.o $(LIBBPF) xdp_redirect_map_user.o
 xdp_redirect_cpu-objs := bpf_load.o $(LIBBPF) xdp_redirect_cpu_user.o
 xdp_monitor-objs := bpf_load.o $(LIBBPF) xdp_monitor_user.o
+xdp_rxq_info-objs := bpf_load.o $(LIBBPF) xdp_rxq_info_user.o
 syscall_tp-objs := bpf_load.o $(LIBBPF) syscall_tp_user.o
 
 # Tell kbuild to always build the programs
@@ -139,6 +141,7 @@ always += xdp_redirect_kern.o
 always += xdp_redirect_map_kern.o
 always += xdp_redirect_cpu_kern.o
 always += xdp_monitor_kern.o
+always += xdp_rxq_info_kern.o
 always += syscall_tp_kern.o
 
 HOSTCFLAGS += -I$(objtree)/usr/include
@@ -182,6 +185,7 @@ HOSTLOADLIBES_xdp_redirect += -lelf
 HOSTLOADLIBES_xdp_redirect_map += -lelf
 HOSTLOADLIBES_xdp_redirect_cpu += -lelf
 HOSTLOADLIBES_xdp_monitor += -lelf
+HOSTLOADLIBES_xdp_rxq_info += -lelf
 HOSTLOADLIBES_syscall_tp += -lelf
 
 # Allows pointing LLC/CLANG to a LLVM backend with bpf support, redefine on cmdline:
diff --git a/samples/bpf/xdp_rxq_info_kern.c b/samples/bpf/xdp_rxq_info_kern.c
new file mode 100644
index 000000000000..19cbd662202c
--- /dev/null
+++ b/samples/bpf/xdp_rxq_info_kern.c
@@ -0,0 +1,96 @@
+/* Example howto extract XDP RX-queue info
+ *
+ * Copyright (c) 2017 Jesper Dangaard Brouer, Red Hat Inc.
+ * Released under terms in GPL version 2.  See COPYING.
+ */
+#include <uapi/linux/bpf.h>
+#include "bpf_helpers.h"
+
+/* Config setup from with userspace
+ *
+ * User-side setup ifindex in config_map, to verify that
+ * ctx->ingress_ifindex is correct (against configured ifindex)
+ */
+struct config {
+	__u32 action;
+	int ifindex;
+};
+struct bpf_map_def SEC("maps") config_map = {
+	.type		= BPF_MAP_TYPE_ARRAY,
+	.key_size	= sizeof(int),
+	.value_size	= sizeof(struct config),
+	.max_entries	= 1,
+};
+
+/* Common stats data record (shared with userspace) */
+struct datarec {
+	__u64 processed;
+	__u64 issue;
+};
+
+struct bpf_map_def SEC("maps") stats_global_map = {
+	.type		= BPF_MAP_TYPE_PERCPU_ARRAY,
+	.key_size	= sizeof(u32),
+	.value_size	= sizeof(struct datarec),
+	.max_entries	= 1,
+};
+
+#define MAX_RXQs 64
+
+/* Stats per rx_queue_index (per CPU) */
+struct bpf_map_def SEC("maps") rx_queue_index_map = {
+	.type		= BPF_MAP_TYPE_PERCPU_ARRAY,
+	.key_size	= sizeof(u32),
+	.value_size	= sizeof(struct datarec),
+	.max_entries	= MAX_RXQs + 1,
+};
+
+SEC("xdp_prog0")
+int  xdp_prognum0(struct xdp_md *ctx)
+{
+	void *data_end = (void *)(long)ctx->data_end;
+	void *data     = (void *)(long)ctx->data;
+	struct datarec *rec, *rxq_rec;
+	int ingress_ifindex;
+	struct config *config;
+	u32 key = 0;
+
+	/* Global stats record */
+	rec = bpf_map_lookup_elem(&stats_global_map, &key);
+	if (!rec)
+		return XDP_ABORTED;
+	rec->processed++;
+
+	/* Accessing ctx->ingress_ifindex, cause BPF to rewrite BPF
+	 * instructions inside kernel to access xdp_rxq->dev->ifindex
+	 */
+	ingress_ifindex = ctx->ingress_ifindex;
+
+	config = bpf_map_lookup_elem(&config_map, &key);
+	if (!config)
+		return XDP_ABORTED;
+
+	/* Simple test: check ctx provided ifindex is as expected */
+	if (ingress_ifindex != config->ifindex) {
+		/* count this error case */
+		rec->issue++;
+		return XDP_ABORTED;
+	}
+
+	/* Update stats per rx_queue_index. Handle if rx_queue_index
+	 * is larger than stats map can contain info for.
+	 */
+	key = ctx->rx_queue_index;
+	if (key >= MAX_RXQs)
+		key = MAX_RXQs;
+	rxq_rec = bpf_map_lookup_elem(&rx_queue_index_map, &key);
+	if (!rxq_rec)
+		return XDP_ABORTED;
+	rxq_rec->processed++;
+	if (key == MAX_RXQs)
+		rxq_rec->issue++;
+
+	return config->action;
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/samples/bpf/xdp_rxq_info_user.c b/samples/bpf/xdp_rxq_info_user.c
new file mode 100644
index 000000000000..d062b0e09924
--- /dev/null
+++ b/samples/bpf/xdp_rxq_info_user.c
@@ -0,0 +1,532 @@
+/*
+ * Copyright (c) 2017 Jesper Dangaard Brouer, Red Hat Inc.
+ * Released under terms in GPL version 2.  See COPYING.
+ */
+static const char *__doc__ = " XDP RX-queue info extract example\n\n"
+	"Monitor how many packets per sec (pps) are received\n"
+	"per NIC RX queue index and which CPU processed the packet\n"
+	;
+
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <string.h>
+#include <unistd.h>
+#include <locale.h>
+#include <sys/resource.h>
+#include <getopt.h>
+#include <net/if.h>
+#include <time.h>
+
+#include <arpa/inet.h>
+#include <linux/if_link.h>
+
+#include "libbpf.h"
+#include "bpf_load.h"
+#include "bpf_util.h"
+
+static int ifindex = -1;
+static char ifname_buf[IF_NAMESIZE];
+static char *ifname;
+
+static __u32 xdp_flags;
+
+/* Exit return codes */
+#define EXIT_OK		0
+#define EXIT_FAIL		1
+#define EXIT_FAIL_OPTION	2
+#define EXIT_FAIL_XDP		3
+#define EXIT_FAIL_BPF		4
+#define EXIT_FAIL_MEM		5
+
+static const struct option long_options[] = {
+	{"help",	no_argument,		NULL, 'h' },
+	{"dev",		required_argument,	NULL, 'd' },
+	{"skb-mode",	no_argument,		NULL, 'S' },
+	{"sec",		required_argument,	NULL, 's' },
+	{"no-separators", no_argument,		NULL, 'z' },
+	{"action",	required_argument,	NULL, 'a' },
+	{0, 0, NULL,  0 }
+};
+
+static void int_exit(int sig)
+{
+	fprintf(stderr,
+		"Interrupted: Removing XDP program on ifindex:%d device:%s\n",
+		ifindex, ifname);
+	if (ifindex > -1)
+		set_link_xdp_fd(ifindex, -1, xdp_flags);
+	exit(EXIT_OK);
+}
+
+struct config {
+	__u32 action;
+	int ifindex;
+};
+#define XDP_ACTION_MAX (XDP_TX + 1)
+#define XDP_ACTION_MAX_STRLEN 11
+static const char *xdp_action_names[XDP_ACTION_MAX] = {
+	[XDP_ABORTED]	= "XDP_ABORTED",
+	[XDP_DROP]	= "XDP_DROP",
+	[XDP_PASS]	= "XDP_PASS",
+	[XDP_TX]	= "XDP_TX",
+};
+
+static const char *action2str(int action)
+{
+	if (action < XDP_ACTION_MAX)
+		return xdp_action_names[action];
+	return NULL;
+}
+
+static int parse_xdp_action(char *action_str)
+{
+	size_t maxlen;
+	__u64 action = -1;
+	int i;
+
+	for (i = 0; i < XDP_ACTION_MAX; i++) {
+		maxlen = XDP_ACTION_MAX_STRLEN;
+		if (strncmp(xdp_action_names[i], action_str, maxlen) == 0) {
+			action = i;
+			break;
+		}
+	}
+	return action;
+}
+
+static void list_xdp_actions(void)
+{
+	int i;
+
+	printf("Available XDP --action <options>\n");
+	for (i = 0; i < XDP_ACTION_MAX; i++)
+		printf("\t%s\n", xdp_action_names[i]);
+	printf("\n");
+}
+
+static void usage(char *argv[])
+{
+	int i;
+
+	printf("\nDOCUMENTATION:\n%s\n", __doc__);
+	printf(" Usage: %s (options-see-below)\n", argv[0]);
+	printf(" Listing options:\n");
+	for (i = 0; long_options[i].name != 0; i++) {
+		printf(" --%-12s", long_options[i].name);
+		if (long_options[i].flag != NULL)
+			printf(" flag (internal value:%d)",
+				*long_options[i].flag);
+		else
+			printf(" short-option: -%c",
+				long_options[i].val);
+		printf("\n");
+	}
+	printf("\n");
+	list_xdp_actions();
+}
+
+#define NANOSEC_PER_SEC 1000000000 /* 10^9 */
+static __u64 gettime(void)
+{
+	struct timespec t;
+	int res;
+
+	res = clock_gettime(CLOCK_MONOTONIC, &t);
+	if (res < 0) {
+		fprintf(stderr, "Error with gettimeofday! (%i)\n", res);
+		exit(EXIT_FAIL);
+	}
+	return (__u64) t.tv_sec * NANOSEC_PER_SEC + t.tv_nsec;
+}
+
+/* Common stats data record shared with _kern.c */
+struct datarec {
+	__u64 processed;
+	__u64 issue;
+};
+struct record {
+	__u64 timestamp;
+	struct datarec total;
+	struct datarec *cpu;
+};
+struct stats_record {
+	struct record stats;
+	struct record *rxq;
+};
+
+static struct datarec *alloc_record_per_cpu(void)
+{
+	unsigned int nr_cpus = bpf_num_possible_cpus();
+	struct datarec *array;
+	size_t size;
+
+	size = sizeof(struct datarec) * nr_cpus;
+	array = malloc(size);
+	memset(array, 0, size);
+	if (!array) {
+		fprintf(stderr, "Mem alloc error (nr_cpus:%u)\n", nr_cpus);
+		exit(EXIT_FAIL_MEM);
+	}
+	return array;
+}
+
+static struct record *alloc_record_per_rxq(void)
+{
+	unsigned int nr_rxqs = map_data[2].def.max_entries;
+	struct record *array;
+	size_t size;
+
+	size = sizeof(struct record) * nr_rxqs;
+	array = malloc(size);
+	memset(array, 0, size);
+	if (!array) {
+		fprintf(stderr, "Mem alloc error (nr_rxqs:%u)\n", nr_rxqs);
+		exit(EXIT_FAIL_MEM);
+	}
+	return array;
+}
+
+static struct stats_record *alloc_stats_record(void)
+{
+	unsigned int nr_rxqs = map_data[2].def.max_entries;
+	struct stats_record *rec;
+	int i;
+
+	rec = malloc(sizeof(*rec));
+	memset(rec, 0, sizeof(*rec));
+	if (!rec) {
+		fprintf(stderr, "Mem alloc error\n");
+		exit(EXIT_FAIL_MEM);
+	}
+	rec->rxq = alloc_record_per_rxq();
+	for (i = 0; i < nr_rxqs; i++)
+		rec->rxq[i].cpu = alloc_record_per_cpu();
+
+	rec->stats.cpu = alloc_record_per_cpu();
+	return rec;
+}
+
+static void free_stats_record(struct stats_record *r)
+{
+	unsigned int nr_rxqs = map_data[2].def.max_entries;
+	int i;
+
+	for (i = 0; i < nr_rxqs; i++)
+		free(r->rxq[i].cpu);
+
+	free(r->rxq);
+	free(r->stats.cpu);
+	free(r);
+}
+
+static bool map_collect_percpu(int fd, __u32 key, struct record *rec)
+{
+	/* For percpu maps, userspace gets a value per possible CPU */
+	unsigned int nr_cpus = bpf_num_possible_cpus();
+	struct datarec values[nr_cpus];
+	__u64 sum_processed = 0;
+	__u64 sum_issue = 0;
+	int i;
+
+	if ((bpf_map_lookup_elem(fd, &key, values)) != 0) {
+		fprintf(stderr,
+			"ERR: bpf_map_lookup_elem failed key:0x%X\n", key);
+		return false;
+	}
+	/* Get time as close as possible to reading map contents */
+	rec->timestamp = gettime();
+
+	/* Record and sum values from each CPU */
+	for (i = 0; i < nr_cpus; i++) {
+		rec->cpu[i].processed = values[i].processed;
+		sum_processed        += values[i].processed;
+		rec->cpu[i].issue = values[i].issue;
+		sum_issue        += values[i].issue;
+	}
+	rec->total.processed = sum_processed;
+	rec->total.issue     = sum_issue;
+	return true;
+}
+
+static void stats_collect(struct stats_record *rec)
+{
+	int fd, i, max_rxqs;
+
+	fd = map_data[1].fd; /* map: stats_global_map */
+	map_collect_percpu(fd, 0, &rec->stats);
+
+	fd = map_data[2].fd; /* map: rx_queue_index_map */
+	max_rxqs = map_data[2].def.max_entries;
+	for (i = 0; i < max_rxqs; i++)
+		map_collect_percpu(fd, i, &rec->rxq[i]);
+}
+
+static double calc_period(struct record *r, struct record *p)
+{
+	double period_ = 0;
+	__u64 period = 0;
+
+	period = r->timestamp - p->timestamp;
+	if (period > 0)
+		period_ = ((double) period / NANOSEC_PER_SEC);
+
+	return period_;
+}
+
+static __u64 calc_pps(struct datarec *r, struct datarec *p, double period_)
+{
+	__u64 packets = 0;
+	__u64 pps = 0;
+
+	if (period_ > 0) {
+		packets = r->processed - p->processed;
+		pps = packets / period_;
+	}
+	return pps;
+}
+
+static __u64 calc_errs_pps(struct datarec *r,
+			    struct datarec *p, double period_)
+{
+	__u64 packets = 0;
+	__u64 pps = 0;
+
+	if (period_ > 0) {
+		packets = r->issue - p->issue;
+		pps = packets / period_;
+	}
+	return pps;
+}
+
+static void stats_print(struct stats_record *stats_rec,
+			struct stats_record *stats_prev,
+			int action)
+{
+	unsigned int nr_cpus = bpf_num_possible_cpus();
+	unsigned int nr_rxqs = map_data[2].def.max_entries;
+	double pps = 0, err = 0;
+	struct record *rec, *prev;
+	double t;
+	int rxq;
+	int i;
+
+	/* Header */
+	printf("\nRunning XDP on dev:%s (ifindex:%d) action:%s\n",
+	       ifname, ifindex, action2str(action));
+
+	/* stats_global_map */
+	{
+		char *fmt_rx = "%-15s %-7d %'-11.0f %'-10.0f %s\n";
+		char *fm2_rx = "%-15s %-7s %'-11.0f\n";
+		char *errstr = "";
+
+		printf("%-15s %-7s %-11s %-11s\n",
+		       "XDP stats", "CPU", "pps", "issue-pps");
+
+		rec  =  &stats_rec->stats;
+		prev = &stats_prev->stats;
+		t = calc_period(rec, prev);
+		for (i = 0; i < nr_cpus; i++) {
+			struct datarec *r = &rec->cpu[i];
+			struct datarec *p = &prev->cpu[i];
+
+			pps = calc_pps     (r, p, t);
+			err = calc_errs_pps(r, p, t);
+			if (err > 0)
+				errstr = "invalid-ifindex";
+			if (pps > 0)
+				printf(fmt_rx, "XDP-RX CPU",
+					i, pps, err, errstr);
+		}
+		pps  = calc_pps     (&rec->total, &prev->total, t);
+		err  = calc_errs_pps(&rec->total, &prev->total, t);
+		printf(fm2_rx, "XDP-RX CPU", "total", pps, err);
+	}
+
+	/* rx_queue_index_map */
+	printf("\n%-15s %-7s %-11s %-11s\n",
+	       "RXQ stats", "RXQ:CPU", "pps", "issue-pps");
+
+	for (rxq = 0; rxq < nr_rxqs; rxq++) {
+		char *fmt_rx = "%-15s %3d:%-3d %'-11.0f %'-10.0f %s\n";
+		char *fm2_rx = "%-15s %3d:%-3s %'-11.0f\n";
+		char *errstr = "";
+		int rxq_ = rxq;
+
+		/* Last RXQ in map catch overflows */
+		if (rxq_ == nr_rxqs - 1)
+			rxq_ = -1;
+
+		rec  =  &stats_rec->rxq[rxq];
+		prev = &stats_prev->rxq[rxq];
+		t = calc_period(rec, prev);
+		for (i = 0; i < nr_cpus; i++) {
+			struct datarec *r = &rec->cpu[i];
+			struct datarec *p = &prev->cpu[i];
+
+			pps = calc_pps     (r, p, t);
+			err = calc_errs_pps(r, p, t);
+			if (err > 0) {
+				if (rxq_ == -1)
+					errstr = "map-overflow-RXQ";
+				else
+					errstr = "err";
+			}
+			if (pps > 0)
+				printf(fmt_rx, "rx_queue_index",
+				       rxq_, i, pps, err, errstr);
+		}
+		pps  = calc_pps     (&rec->total, &prev->total, t);
+		err  = calc_errs_pps(&rec->total, &prev->total, t);
+		if (pps || err)
+			printf(fm2_rx, "rx_queue_index", rxq_, "sum", pps, err);
+	}
+}
+
+
+/* Pointer swap trick */
+static inline void swap(struct stats_record **a, struct stats_record **b)
+{
+	struct stats_record *tmp;
+
+	tmp = *a;
+	*a = *b;
+	*b = tmp;
+}
+
+static void stats_poll(int interval, int action)
+{
+	struct stats_record *record, *prev;
+
+	record = alloc_stats_record();
+	prev   = alloc_stats_record();
+	stats_collect(record);
+
+	while (1) {
+		swap(&prev, &record);
+		stats_collect(record);
+		stats_print(record, prev, action);
+		sleep(interval);
+	}
+
+	free_stats_record(record);
+	free_stats_record(prev);
+}
+
+
+int main(int argc, char **argv)
+{
+	struct rlimit r = {10 * 1024 * 1024, RLIM_INFINITY};
+	bool use_separators = true;
+	struct config cfg = { 0 };
+	char filename[256];
+	int longindex = 0;
+	int interval = 2;
+	__u32 key = 0;
+	int opt, err;
+
+	char action_str_buf[XDP_ACTION_MAX_STRLEN + 1 /* for \0 */] = { 0 };
+	int action = XDP_PASS; /* Default action */
+	char *action_str = NULL;
+
+	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+
+	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
+		perror("setrlimit(RLIMIT_MEMLOCK)");
+		return 1;
+	}
+
+	if (load_bpf_file(filename)) {
+		fprintf(stderr, "ERR in load_bpf_file(): %s", bpf_log_buf);
+		return EXIT_FAIL;
+	}
+
+	if (!prog_fd[0]) {
+		fprintf(stderr, "ERR: load_bpf_file: %s\n", strerror(errno));
+		return EXIT_FAIL;
+	}
+
+	/* Parse commands line args */
+	while ((opt = getopt_long(argc, argv, "hSd:",
+				  long_options, &longindex)) != -1) {
+		switch (opt) {
+		case 'd':
+			if (strlen(optarg) >= IF_NAMESIZE) {
+				fprintf(stderr, "ERR: --dev name too long\n");
+				goto error;
+			}
+			ifname = (char *)&ifname_buf;
+			strncpy(ifname, optarg, IF_NAMESIZE);
+			ifindex = if_nametoindex(ifname);
+			if (ifindex == 0) {
+				fprintf(stderr,
+					"ERR: --dev name unknown err(%d):%s\n",
+					errno, strerror(errno));
+				goto error;
+			}
+			break;
+		case 's':
+			interval = atoi(optarg);
+			break;
+		case 'S':
+			xdp_flags |= XDP_FLAGS_SKB_MODE;
+			break;
+		case 'z':
+			use_separators = false;
+			break;
+		case 'a':
+			action_str = (char *)&action_str_buf;
+			strncpy(action_str, optarg, XDP_ACTION_MAX_STRLEN);
+			break;
+		case 'h':
+		error:
+		default:
+			usage(argv);
+			return EXIT_FAIL_OPTION;
+		}
+	}
+	/* Required option */
+	if (ifindex == -1) {
+		fprintf(stderr, "ERR: required option --dev missing\n");
+		usage(argv);
+		return EXIT_FAIL_OPTION;
+	}
+	cfg.ifindex = ifindex;
+
+	/* Parse action string */
+	if (action_str) {
+		action = parse_xdp_action(action_str);
+		if (action < 0) {
+			fprintf(stderr, "ERR: Invalid XDP --action: %s\n",
+				action_str);
+			list_xdp_actions();
+			return EXIT_FAIL_OPTION;
+		}
+	}
+	cfg.action = action;
+
+	/* Trick to pretty printf with thousands separators use %' */
+	if (use_separators)
+		setlocale(LC_NUMERIC, "en_US");
+
+	/* User-side setup ifindex in config_map */
+	err = bpf_map_update_elem(map_fd[0], &key, &cfg, 0);
+	if (err) {
+		fprintf(stderr, "Store config failed (err:%d)\n", err);
+		exit(EXIT_FAIL_BPF);
+	}
+
+	/* Remove XDP program when program is interrupted */
+	signal(SIGINT, int_exit);
+
+	if (set_link_xdp_fd(ifindex, prog_fd[0], xdp_flags) < 0) {
+		fprintf(stderr, "link set xdp fd failed\n");
+		return EXIT_FAIL_XDP;
+	}
+
+	stats_poll(interval, action);
+	return EXIT_OK;
+}

Re: [bpf-next V2 PATCH 01/14] xdp: base API for new XDP rx-queue info concept

[Jakub Kicinski]

On Fri, 22 Dec 2017 18:11:39 +0100, Jesper Dangaard Brouer wrote:
> +struct xdp_rxq_info {
> +	struct net_device *dev;
> +	u32 queue_index;
> +	u32 reg_state;
> +} ____cacheline_aligned; /* perf critical, avoid false-sharing */

I'm assuming this is cacheline_aligned, because of some stuff you will
add here in the future for the completion path?  (The comment could
mention that this data is read-mostly.)  Drivers are likely to already
have a read-mostly (or unused-mostly) section of the rx ring structure.
Would it be possible to define this in a way that would allow people
who carefully lay out their data path structures to save cache space?

Re: [bpf-next V2 PATCH 13/14] bpf: finally expose xdp_rxq_info to XDP bpf-programs

[Alexei Starovoitov]

On Fri, Dec 22, 2017 at 06:12:41PM +0100, Jesper Dangaard Brouer wrote:
> Now all XDP driver have been updated to setup xdp_rxq_info and assign
> this to xdp_buff->rxq.  Thus, it is now safe to enable access to some
> of the xdp_rxq_info struct members.
> 
> This patch extend xdp_md and expose UAPI to userspace for
> ingress_ifindex and rx_queue_index.  Access happens via bpf
> instruction rewrite, that load data directly from struct xdp_rxq_info.
> 
> * ingress_ifindex map to xdp_rxq_info->dev->ifindex
> * rx_queue_index  map to xdp_rxq_info->queue_index
> 
> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
...
> diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
> index 69eabfcb9bdb..a6000a95d40e 100644
> --- a/include/uapi/linux/bpf.h
> +++ b/include/uapi/linux/bpf.h
> @@ -899,6 +899,9 @@ struct xdp_md {
>  	__u32 data;
>  	__u32 data_end;
>  	__u32 data_meta;
> +	/* Below access go though struct xdp_rxq_info */
> +	__u32 ingress_ifindex; /* rxq->dev->ifindex */
> +	__u32 rx_queue_index;  /* rxq->queue_index  */
>  };

Acked-by: Alexei Starovoitov <ast@kernel.org>

I think this is very useful extension and I hope driver maintainers
will do a timely review of corresponding patches.

my only nit:
please use SPDX license header for two new files added in patch 14.

Re: [bpf-next V2 PATCH 01/14] xdp: base API for new XDP rx-queue info concept

[Jesper Dangaard Brouer]

On Fri, 22 Dec 2017 16:14:43 -0800
Jakub Kicinski <jakub.kicinski@netronome.com> wrote:

> On Fri, 22 Dec 2017 18:11:39 +0100, Jesper Dangaard Brouer wrote:
> > +struct xdp_rxq_info {
> > +	struct net_device *dev;
> > +	u32 queue_index;
> > +	u32 reg_state;
> > +} ____cacheline_aligned; /* perf critical, avoid false-sharing */  
> 
> I'm assuming this is cacheline_aligned, because of some stuff you will
> add here in the future for the completion path?  (The comment could
> mention that this data is read-mostly.)  Drivers are likely to already
> have a read-mostly (or unused-mostly) section of the rx ring structure.
> Would it be possible to define this in a way that would allow people
> who carefully lay out their data path structures to save cache space?

Please lets keep such struct layout micro-optimization for later.
Having a fixed full cache-line for this struct makes it easier to avoid
any false-sharing day-1.  If we don't do this, then every time we
extend/change this struct, we (you?) have to go through every drivers
RX-ring alignment and make sure things didn't move around.  Also if
some driver developer change his own RX-ring struct layout then we/he
have to verify struct layouts.   The hole plan is this struct need to
be extended, lets help ourselves and keep it simple.  Once the size of
this struct have stabilized, then we can circle back and optimize such
stuff. Fair enough?

-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  LinkedIn: http://www.linkedin.com/in/brouer

Re: [bpf-next V2 PATCH 06/14] mlx4: setup xdp_rxq_info

[Tariq Toukan]

On 22/12/2017 7:12 PM, Jesper Dangaard Brouer wrote:
> Driver hook points for xdp_rxq_info:
>   * reg  : mlx4_en_create_rx_ring
>   * unreg: mlx4_en_destroy_rx_ring
> 
> Tested on actual hardware.
> 
> Cc: Tariq Toukan <tariqt@mellanox.com>
> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>

Reviewed-by: Tariq Toukan <tariqt@mellanox.com>

Thanks.

Re: [bpf-next V2 PATCH 11/14] virtio_net: setup xdp_rxq_info

[Jesper Dangaard Brouer]

On Fri, 22 Dec 2017 18:12:31 +0100
Jesper Dangaard Brouer <brouer@redhat.com> wrote:

> The virtio_net driver doesn't dynamically change the RX-ring queue
> layout and backing pages, but instead reject XDP setup if all the
> conditions for XDP is not meet.  Thus, the xdp_rxq_info also remains
> fairly static.  This allow us to simply add the reg/unreg to
> net_device open/close functions.
> 
> Driver hook points for xdp_rxq_info:
>  * reg  : virtnet_open
>  * unreg: virtnet_close
> 
> Cc: "Michael S. Tsirkin" <mst@redhat.com>
> Cc: Jason Wang <jasowang@redhat.com>
> Cc: virtualization@lists.linux-foundation.org
> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
> ---
>  drivers/net/virtio_net.c |   12 +++++++++++-

Found a bug while testing this... I forgot to update receive_mergeable() too.

I'll send a V3

-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  LinkedIn: http://www.linkedin.com/in/brouer

Re: [bpf-next V2 PATCH 11/14] virtio_net: setup xdp_rxq_info

[Jesper Dangaard Brouer]

On Fri, 22 Dec 2017 18:12:31 +0100
Jesper Dangaard Brouer <brouer@redhat.com> wrote:

> The virtio_net driver doesn't dynamically change the RX-ring queue
> layout and backing pages, but instead reject XDP setup if all the
> conditions for XDP is not meet.  Thus, the xdp_rxq_info also remains
> fairly static.  This allow us to simply add the reg/unreg to
> net_device open/close functions.
> 
> Driver hook points for xdp_rxq_info:
>  * reg  : virtnet_open
>  * unreg: virtnet_close
> 
> Cc: "Michael S. Tsirkin" <mst@redhat.com>
> Cc: Jason Wang <jasowang@redhat.com>
> Cc: virtualization@lists.linux-foundation.org
> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
> ---
>  drivers/net/virtio_net.c |   12 +++++++++++-

Found a bug while testing this... I forgot to update receive_mergeable() too.

I'll send a V3

-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  LinkedIn: http://www.linkedin.com/in/brouer

RE: [bpf-next V2 PATCH 05/14] xdp/qede: setup xdp_rxq_info and intro xdp_rxq_info_is_reg

[Chopra, Manish]

> -----Original Message-----
> From: Jesper Dangaard Brouer [mailto:brouer@redhat.com]
> Sent: Friday, December 22, 2017 10:42 PM
> To: Daniel Borkmann <borkmann@iogearbox.net>; Alexei Starovoitov
> <alexei.starovoitov@gmail.com>
> Cc: bjorn.topel@intel.com; netdev@vger.kernel.org; Jesper Dangaard Brouer
> <brouer@redhat.com>; Elior, Ariel <Ariel.Elior@cavium.com>;
> dsahern@gmail.com; gospo@broadcom.com; Dept-Eng Everest Linux L2 <Dept-
> EngEverestLinuxL2@cavium.com>; michael.chan@broadcom.com
> Subject: [bpf-next V2 PATCH 05/14] xdp/qede: setup xdp_rxq_info and intro
> xdp_rxq_info_is_reg
> 
> The driver code qede_free_fp_array() depend on kfree() can be called with a
> NULL pointer. This stems from the qede_alloc_fp_array() function which either
> (kz)alloc memory for fp->txq or fp->rxq.
> This also simplifies error handling code in case of memory allocation failures,
> but xdp_rxq_info_unreg need to know the difference.
> 
> Introduce xdp_rxq_info_is_reg() to handle if a memory allocation fails and
> detect this is the failure path by seeing that xdp_rxq_info was not registred yet,
> which first happens after successful alloaction in qede_init_fp().
> 
> Driver hook points for xdp_rxq_info:
>  * reg  : qede_init_fp
>  * unreg: qede_free_fp_array
> 
> Tested on actual hardware with samples/bpf program.
> 
> V2: Driver have no proper error path for failed XDP RX-queue info reg, as
> qede_init_fp() is a void function.
> 
> Cc: everest-linux-l2@cavium.com
> Cc: Ariel Elior <Ariel.Elior@cavium.com>
> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
> ---
>  drivers/net/ethernet/qlogic/qede/qede.h      |    2 ++
>  drivers/net/ethernet/qlogic/qede/qede_fp.c   |    1 +
>  drivers/net/ethernet/qlogic/qede/qede_main.c |   10 ++++++++++
>  include/net/xdp.h                            |    1 +
>  net/core/xdp.c                               |    6 ++++++
>  5 files changed, 20 insertions(+)
> 
> diff --git a/drivers/net/ethernet/qlogic/qede/qede.h
> b/drivers/net/ethernet/qlogic/qede/qede.h
> index a3a70ade411f..62f47736511b 100644
> --- a/drivers/net/ethernet/qlogic/qede/qede.h
> +++ b/drivers/net/ethernet/qlogic/qede/qede.h
> @@ -40,6 +40,7 @@
>  #include <linux/kernel.h>
>  #include <linux/mutex.h>
>  #include <linux/bpf.h>
> +#include <net/xdp.h>
>  #include <linux/qed/qede_rdma.h>
>  #include <linux/io.h>
>  #ifdef CONFIG_RFS_ACCEL
> @@ -345,6 +346,7 @@ struct qede_rx_queue {
>  	u64 xdp_no_pass;
> 
>  	void *handle;
> +	struct xdp_rxq_info xdp_rxq;
>  };
> 
>  union db_prod {
> diff --git a/drivers/net/ethernet/qlogic/qede/qede_fp.c
> b/drivers/net/ethernet/qlogic/qede/qede_fp.c
> index 48ec4c56cddf..dafc079ab6b9 100644
> --- a/drivers/net/ethernet/qlogic/qede/qede_fp.c
> +++ b/drivers/net/ethernet/qlogic/qede/qede_fp.c
> @@ -1006,6 +1006,7 @@ static bool qede_rx_xdp(struct qede_dev *edev,
>  	xdp.data = xdp.data_hard_start + *data_offset;
>  	xdp_set_data_meta_invalid(&xdp);
>  	xdp.data_end = xdp.data + *len;
> +	xdp.rxq = &rxq->xdp_rxq;
> 
>  	/* Queues always have a full reset currently, so for the time
>  	 * being until there's atomic program replace just mark read diff --git
> a/drivers/net/ethernet/qlogic/qede/qede_main.c
> b/drivers/net/ethernet/qlogic/qede/qede_main.c
> index 57332b3e5e64..24160f1fd0e5 100644
> --- a/drivers/net/ethernet/qlogic/qede/qede_main.c
> +++ b/drivers/net/ethernet/qlogic/qede/qede_main.c
> @@ -762,6 +762,12 @@ static void qede_free_fp_array(struct qede_dev *edev)
>  			fp = &edev->fp_array[i];
> 
>  			kfree(fp->sb_info);
> +			/* Handle mem alloc failure case where qede_init_fp
> +			 * didn't register xdp_rxq_info yet.
> +			 * Implicit only (fp->type & QEDE_FASTPATH_RX)
> +			 */
> +			if (fp->rxq && xdp_rxq_info_is_reg(&fp->rxq->xdp_rxq))
> +				xdp_rxq_info_unreg(&fp->rxq->xdp_rxq);

Isn't this sufficient just ?
If (fp->rxq)
	xdp_rxq_info_unreg(&fp->rxq->xdp_rxq);

xdp_rxq_info_is_reg() API seems unnecessary to me, xdp_rxq_info_unreg() seems to be taking care of the case
if it's not registered then WARN already, I think instead of adding these checks in individual drivers, better handle it properly in xdp_rxq_info_unreg() ?

>  			kfree(fp->rxq);
>  			kfree(fp->xdp_tx);
>  			kfree(fp->txq);
> @@ -1498,6 +1504,10 @@ static void qede_init_fp(struct qede_dev *edev)
>  			else
>  				fp->rxq->data_direction =
> DMA_FROM_DEVICE;
>  			fp->rxq->dev = &edev->pdev->dev;
> +
> +			/* Driver have no error path from here */
> +			WARN_ON(xdp_rxq_info_reg(&fp->rxq->xdp_rxq, edev-
> >ndev,
> +						 fp->rxq->rxq_id) < 0);
>  		}

We will reach to this point only when fp->rxq and edev are valid
I don't think that xdp_rxq_info_reg() will fail ever in that case.

Re: [bpf-next V2 PATCH 05/14] xdp/qede: setup xdp_rxq_info and intro xdp_rxq_info_is_reg

[Jesper Dangaard Brouer]

On Wed, 27 Dec 2017 10:37:10 +0000
"Chopra, Manish" <Manish.Chopra@cavium.com> wrote:

> > -----Original Message-----
> > From: Jesper Dangaard Brouer [mailto:brouer@redhat.com]
> > Sent: Friday, December 22, 2017 10:42 PM
> > To: Daniel Borkmann <borkmann@iogearbox.net>; Alexei Starovoitov
> > <alexei.starovoitov@gmail.com>
> > Cc: bjorn.topel@intel.com; netdev@vger.kernel.org; Jesper Dangaard Brouer
> > <brouer@redhat.com>; Elior, Ariel <Ariel.Elior@cavium.com>;
> > dsahern@gmail.com; gospo@broadcom.com; Dept-Eng Everest Linux L2 <Dept-  
> > EngEverestLinuxL2@cavium.com>; michael.chan@broadcom.com  
> > Subject: [bpf-next V2 PATCH 05/14] xdp/qede: setup xdp_rxq_info and intro
> > xdp_rxq_info_is_reg
> > 
> > The driver code qede_free_fp_array() depend on kfree() can be called with a
> > NULL pointer. This stems from the qede_alloc_fp_array() function which either
> > (kz)alloc memory for fp->txq or fp->rxq.
> > This also simplifies error handling code in case of memory allocation failures,
> > but xdp_rxq_info_unreg need to know the difference.
> > 
> > Introduce xdp_rxq_info_is_reg() to handle if a memory allocation fails and
> > detect this is the failure path by seeing that xdp_rxq_info was not registred yet,
> > which first happens after successful alloaction in qede_init_fp().
> > 
> > Driver hook points for xdp_rxq_info:
> >  * reg  : qede_init_fp
> >  * unreg: qede_free_fp_array
> > 
> > Tested on actual hardware with samples/bpf program.
> > 
> > V2: Driver have no proper error path for failed XDP RX-queue info reg, as
> > qede_init_fp() is a void function.
> > 
> > Cc: everest-linux-l2@cavium.com
> > Cc: Ariel Elior <Ariel.Elior@cavium.com>
> > Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
> > ---
> >  drivers/net/ethernet/qlogic/qede/qede.h      |    2 ++
> >  drivers/net/ethernet/qlogic/qede/qede_fp.c   |    1 +
> >  drivers/net/ethernet/qlogic/qede/qede_main.c |   10 ++++++++++
> >  include/net/xdp.h                            |    1 +
> >  net/core/xdp.c                               |    6 ++++++
> >  5 files changed, 20 insertions(+)
> > 
> > diff --git a/drivers/net/ethernet/qlogic/qede/qede.h
> > b/drivers/net/ethernet/qlogic/qede/qede.h
> > index a3a70ade411f..62f47736511b 100644
> > --- a/drivers/net/ethernet/qlogic/qede/qede.h
> > +++ b/drivers/net/ethernet/qlogic/qede/qede.h
> > @@ -40,6 +40,7 @@
> >  #include <linux/kernel.h>
> >  #include <linux/mutex.h>
> >  #include <linux/bpf.h>
> > +#include <net/xdp.h>
> >  #include <linux/qed/qede_rdma.h>
> >  #include <linux/io.h>
> >  #ifdef CONFIG_RFS_ACCEL
> > @@ -345,6 +346,7 @@ struct qede_rx_queue {
> >  	u64 xdp_no_pass;
> > 
> >  	void *handle;
> > +	struct xdp_rxq_info xdp_rxq;
> >  };
> > 
> >  union db_prod {
> > diff --git a/drivers/net/ethernet/qlogic/qede/qede_fp.c
> > b/drivers/net/ethernet/qlogic/qede/qede_fp.c
> > index 48ec4c56cddf..dafc079ab6b9 100644
> > --- a/drivers/net/ethernet/qlogic/qede/qede_fp.c
> > +++ b/drivers/net/ethernet/qlogic/qede/qede_fp.c
> > @@ -1006,6 +1006,7 @@ static bool qede_rx_xdp(struct qede_dev *edev,
> >  	xdp.data = xdp.data_hard_start + *data_offset;
> >  	xdp_set_data_meta_invalid(&xdp);
> >  	xdp.data_end = xdp.data + *len;
> > +	xdp.rxq = &rxq->xdp_rxq;
> > 
> >  	/* Queues always have a full reset currently, so for the time
> >  	 * being until there's atomic program replace just mark read diff --git
> > a/drivers/net/ethernet/qlogic/qede/qede_main.c
> > b/drivers/net/ethernet/qlogic/qede/qede_main.c
> > index 57332b3e5e64..24160f1fd0e5 100644
> > --- a/drivers/net/ethernet/qlogic/qede/qede_main.c
> > +++ b/drivers/net/ethernet/qlogic/qede/qede_main.c
> > @@ -762,6 +762,12 @@ static void qede_free_fp_array(struct qede_dev *edev)
> >  			fp = &edev->fp_array[i];
> > 
> >  			kfree(fp->sb_info);
> > +			/* Handle mem alloc failure case where qede_init_fp
> > +			 * didn't register xdp_rxq_info yet.
> > +			 * Implicit only (fp->type & QEDE_FASTPATH_RX)
> > +			 */
> > +			if (fp->rxq && xdp_rxq_info_is_reg(&fp->rxq->xdp_rxq))
> > +				xdp_rxq_info_unreg(&fp->rxq->xdp_rxq);  
> 
> Isn't this sufficient just ?
> If (fp->rxq)
> 	xdp_rxq_info_unreg(&fp->rxq->xdp_rxq);

No, it is not sufficient.

Your driver have qede_alloc_fp_array() which for_each_queue (kz)alloc
memory.  If one of the memory allocations fail, then memory is
free'ed/"rolled-back" in qede_free_fp_array().  Thus, some of the
fp->rxq pointers will be allocated, but xdp_rxq_info_reg() have not
"registered" it yet.  Thus, this _is_ needed to correctly handle memory
failures.

> xdp_rxq_info_is_reg() API seems unnecessary to me,
> xdp_rxq_info_unreg() seems to be taking care of the case if it's not
> registered then WARN already, I think instead of adding these checks
> in individual drivers, better handle it properly in
> xdp_rxq_info_unreg() ?

The xdp_rxq_info_is_reg() API is needed in your driver, and I also found
a need for this in the Broadcom bnxt_en driver.


> >  			kfree(fp->rxq);
> >  			kfree(fp->xdp_tx);
> >  			kfree(fp->txq);
> > @@ -1498,6 +1504,10 @@ static void qede_init_fp(struct qede_dev *edev)
> >  			else
> >  				fp->rxq->data_direction =
> > DMA_FROM_DEVICE;
> >  			fp->rxq->dev = &edev->pdev->dev;
> > +
> > +			/* Driver have no error path from here */
> > +			WARN_ON(xdp_rxq_info_reg(&fp->rxq->xdp_rxq, edev-  
> > >ndev,  
> > +						 fp->rxq->rxq_id) < 0);
> >  		}  
> 
> We will reach to this point only when fp->rxq and edev are valid
> I don't think that xdp_rxq_info_reg() will fail ever in that case.

With the current implementation in xdp.c, I agree that this case will
never fail in your driver.  There is a clear expectation, that this API
will be extended (to support per RX-ring memory "return/free" API) and
that "will-never-fail" assumption will likely change...

-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  LinkedIn: http://www.linkedin.com/in/brouer