[PATCH v4 net-next 0/3] add multi-buff support for xdp running in generic mode

[PATCH v4 net-next 0/3] add multi-buff support for xdp running in generic mode

[Lorenzo Bianconi]

Introduce multi-buffer support for xdp running in generic mode not always
linearizing the skb in netif_receive_generic_xdp routine.
Introduce page_pool in softnet_data structure

Changes since v3:
- introduce page_pool in softnet_data structure
- rely on page_pools for xdp_generic code
Changes since v2:
- rely on napi_alloc_frag() and napi_build_skb() to build the new skb
Changes since v1:
- explicitly keep the skb segmented in netif_skb_check_for_generic_xdp() and
  do not rely on pskb_expand_head()

Lorenzo Bianconi (3):
  net: introduce page_pool pointer in softnet_data percpu struct
  xdp: rely on skb pointer reference in do_xdp_generic and
    netif_receive_generic_xdp
  xdp: add multi-buff support for xdp running in generic mode

 drivers/net/tun.c               |   4 +-
 include/linux/netdevice.h       |   3 +-
 include/net/page_pool/helpers.h |   5 +
 include/net/page_pool/types.h   |   2 +-
 net/core/dev.c                  | 165 ++++++++++++++++++++++++++++----
 net/core/skbuff.c               |   5 +-
 6 files changed, 160 insertions(+), 24 deletions(-)

-- 
2.43.0

[PATCH v4 net-next 1/3] net: introduce page_pool pointer in softnet_data percpu struct

[Lorenzo Bianconi]

Allocate percpu page_pools in softnet_data.
Moreover add cpuid filed in page_pool struct in order to recycle the
page in the page_pool "hot" cache if napi_pp_put_page() is running on
the same cpu.
This is a preliminary patch to add xdp multi-buff support for xdp running
in generic mode.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
---
 include/linux/netdevice.h       |  1 +
 include/net/page_pool/helpers.h |  5 +++++
 include/net/page_pool/types.h   |  2 +-
 net/core/dev.c                  | 28 +++++++++++++++++++++++++++-
 net/core/skbuff.c               |  5 +++--
 5 files changed, 37 insertions(+), 4 deletions(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 1b935ee341b4..30b6a3f601fe 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -3319,6 +3319,7 @@ struct softnet_data {
 	int			defer_count;
 	int			defer_ipi_scheduled;
 	struct sk_buff		*defer_list;
+	struct page_pool	*page_pool;
 	call_single_data_t	defer_csd;
 };
 
diff --git a/include/net/page_pool/helpers.h b/include/net/page_pool/helpers.h
index 7dc65774cde5..b0da1fdb62dc 100644
--- a/include/net/page_pool/helpers.h
+++ b/include/net/page_pool/helpers.h
@@ -393,4 +393,9 @@ static inline void page_pool_nid_changed(struct page_pool *pool, int new_nid)
 		page_pool_update_nid(pool, new_nid);
 }
 
+static inline void page_pool_set_cpuid(struct page_pool *pool, int cpuid)
+{
+	pool->cpuid = cpuid;
+}
+
 #endif /* _NET_PAGE_POOL_HELPERS_H */
diff --git a/include/net/page_pool/types.h b/include/net/page_pool/types.h
index ac286ea8ce2d..75396f107b20 100644
--- a/include/net/page_pool/types.h
+++ b/include/net/page_pool/types.h
@@ -127,7 +127,7 @@ struct page_pool_stats {
 
 struct page_pool {
 	struct page_pool_params_fast p;
-
+	int cpuid;
 	bool has_init_callback;
 
 	long frag_users;
diff --git a/net/core/dev.c b/net/core/dev.c
index 0432b04cf9b0..4c3d82fcf5b5 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -153,6 +153,8 @@
 #include <linux/prandom.h>
 #include <linux/once_lite.h>
 #include <net/netdev_rx_queue.h>
+#include <net/page_pool/types.h>
+#include <net/page_pool/helpers.h>
 
 #include "dev.h"
 #include "net-sysfs.h"
@@ -11670,12 +11672,14 @@ static void __init net_dev_struct_check(void)
  *
  */
 
+#define SD_PAGE_POOL_RING_SIZE	256
 /*
  *       This is called single threaded during boot, so no need
  *       to take the rtnl semaphore.
  */
 static int __init net_dev_init(void)
 {
+	struct softnet_data *sd;
 	int i, rc = -ENOMEM;
 
 	BUG_ON(!dev_boot_phase);
@@ -11701,10 +11705,14 @@ static int __init net_dev_init(void)
 
 	for_each_possible_cpu(i) {
 		struct work_struct *flush = per_cpu_ptr(&flush_works, i);
-		struct softnet_data *sd = &per_cpu(softnet_data, i);
+		struct page_pool_params page_pool_params = {
+			.pool_size = SD_PAGE_POOL_RING_SIZE,
+			.nid = NUMA_NO_NODE,
+		};
 
 		INIT_WORK(flush, flush_backlog);
 
+		sd = &per_cpu(softnet_data, i);
 		skb_queue_head_init(&sd->input_pkt_queue);
 		skb_queue_head_init(&sd->process_queue);
 #ifdef CONFIG_XFRM_OFFLOAD
@@ -11722,6 +11730,13 @@ static int __init net_dev_init(void)
 		init_gro_hash(&sd->backlog);
 		sd->backlog.poll = process_backlog;
 		sd->backlog.weight = weight_p;
+
+		sd->page_pool = page_pool_create(&page_pool_params);
+		if (IS_ERR(sd->page_pool)) {
+			sd->page_pool = NULL;
+			goto out;
+		}
+		page_pool_set_cpuid(sd->page_pool, i);
 	}
 
 	dev_boot_phase = 0;
@@ -11749,6 +11764,17 @@ static int __init net_dev_init(void)
 	WARN_ON(rc < 0);
 	rc = 0;
 out:
+	if (rc < 0) {
+		for_each_possible_cpu(i) {
+			sd = &per_cpu(softnet_data, i);
+			if (!sd->page_pool)
+				continue;
+
+			page_pool_destroy(sd->page_pool);
+			sd->page_pool = NULL;
+		}
+	}
+
 	return rc;
 }
 
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index b157efea5dea..4bc0a7f98241 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -918,9 +918,10 @@ bool napi_pp_put_page(struct page *page, bool napi_safe)
 	 */
 	if (napi_safe || in_softirq()) {
 		const struct napi_struct *napi = READ_ONCE(pp->p.napi);
+		unsigned int cpuid = smp_processor_id();
 
-		allow_direct = napi &&
-			READ_ONCE(napi->list_owner) == smp_processor_id();
+		allow_direct = napi && READ_ONCE(napi->list_owner) == cpuid;
+		allow_direct |= (pp->cpuid == cpuid);
 	}
 
 	/* Driver set this to memory recycling info. Reset it on recycle.
-- 
2.43.0

[PATCH v4 net-next 2/3] xdp: rely on skb pointer reference in do_xdp_generic and netif_receive_generic_xdp

[Lorenzo Bianconi]

Rely on skb pointer reference instead of the skb pointer in do_xdp_generic and
netif_receive_generic_xdp routine signatures. This is a preliminary patch to add
multi-buff support for xdp running in generic mode.

Acked-by: Jesper Dangaard Brouer <hawk@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
---
 drivers/net/tun.c         |  4 ++--
 include/linux/netdevice.h |  2 +-
 net/core/dev.c            | 16 +++++++++-------
 3 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index afa5497f7c35..206adddff699 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -1921,7 +1921,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
 		rcu_read_lock();
 		xdp_prog = rcu_dereference(tun->xdp_prog);
 		if (xdp_prog) {
-			ret = do_xdp_generic(xdp_prog, skb);
+			ret = do_xdp_generic(xdp_prog, &skb);
 			if (ret != XDP_PASS) {
 				rcu_read_unlock();
 				local_bh_enable();
@@ -2511,7 +2511,7 @@ static int tun_xdp_one(struct tun_struct *tun,
 	skb_record_rx_queue(skb, tfile->queue_index);
 
 	if (skb_xdp) {
-		ret = do_xdp_generic(xdp_prog, skb);
+		ret = do_xdp_generic(xdp_prog, &skb);
 		if (ret != XDP_PASS) {
 			ret = 0;
 			goto out;
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 30b6a3f601fe..d850ead7f9cd 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -3953,7 +3953,7 @@ static inline void dev_consume_skb_any(struct sk_buff *skb)
 u32 bpf_prog_run_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp,
 			     struct bpf_prog *xdp_prog);
 void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog);
-int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff *skb);
+int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff **pskb);
 int netif_rx(struct sk_buff *skb);
 int __netif_rx(struct sk_buff *skb);
 
diff --git a/net/core/dev.c b/net/core/dev.c
index 4c3d82fcf5b5..14554698b1fa 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4916,10 +4916,11 @@ u32 bpf_prog_run_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp,
 	return act;
 }
 
-static u32 netif_receive_generic_xdp(struct sk_buff *skb,
+static u32 netif_receive_generic_xdp(struct sk_buff **pskb,
 				     struct xdp_buff *xdp,
 				     struct bpf_prog *xdp_prog)
 {
+	struct sk_buff *skb = *pskb;
 	u32 act = XDP_DROP;
 
 	/* Reinjected packets coming from act_mirred or similar should
@@ -5000,24 +5001,24 @@ void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog)
 
 static DEFINE_STATIC_KEY_FALSE(generic_xdp_needed_key);
 
-int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff *skb)
+int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff **pskb)
 {
 	if (xdp_prog) {
 		struct xdp_buff xdp;
 		u32 act;
 		int err;
 
-		act = netif_receive_generic_xdp(skb, &xdp, xdp_prog);
+		act = netif_receive_generic_xdp(pskb, &xdp, xdp_prog);
 		if (act != XDP_PASS) {
 			switch (act) {
 			case XDP_REDIRECT:
-				err = xdp_do_generic_redirect(skb->dev, skb,
+				err = xdp_do_generic_redirect((*pskb)->dev, *pskb,
 							      &xdp, xdp_prog);
 				if (err)
 					goto out_redir;
 				break;
 			case XDP_TX:
-				generic_xdp_tx(skb, xdp_prog);
+				generic_xdp_tx(*pskb, xdp_prog);
 				break;
 			}
 			return XDP_DROP;
@@ -5025,7 +5026,7 @@ int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff *skb)
 	}
 	return XDP_PASS;
 out_redir:
-	kfree_skb_reason(skb, SKB_DROP_REASON_XDP);
+	kfree_skb_reason(*pskb, SKB_DROP_REASON_XDP);
 	return XDP_DROP;
 }
 EXPORT_SYMBOL_GPL(do_xdp_generic);
@@ -5348,7 +5349,8 @@ static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc,
 		int ret2;
 
 		migrate_disable();
-		ret2 = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog), skb);
+		ret2 = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog),
+				      &skb);
 		migrate_enable();
 
 		if (ret2 != XDP_PASS) {
-- 
2.43.0

[PATCH v4 net-next 3/3] xdp: add multi-buff support for xdp running in generic mode

[Lorenzo Bianconi]

Similar to native xdp, do not always linearize the skb in
netif_receive_generic_xdp routine but create a non-linear xdp_buff to be
processed by the eBPF program. This allow to add  multi-buffer support
for xdp running in generic mode.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
---
 net/core/dev.c | 121 +++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 111 insertions(+), 10 deletions(-)

diff --git a/net/core/dev.c b/net/core/dev.c
index 14554698b1fa..3826e0ea08e3 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4854,6 +4854,12 @@ u32 bpf_prog_run_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp,
 	xdp_init_buff(xdp, frame_sz, &rxqueue->xdp_rxq);
 	xdp_prepare_buff(xdp, hard_start, skb_headroom(skb) - mac_len,
 			 skb_headlen(skb) + mac_len, true);
+	if (skb_is_nonlinear(skb)) {
+		skb_shinfo(skb)->xdp_frags_size = skb->data_len;
+		xdp_buff_set_frags_flag(xdp);
+	} else {
+		xdp_buff_clear_frags_flag(xdp);
+	}
 
 	orig_data_end = xdp->data_end;
 	orig_data = xdp->data;
@@ -4883,6 +4889,14 @@ u32 bpf_prog_run_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp,
 		skb->len += off; /* positive on grow, negative on shrink */
 	}
 
+	/* XDP frag metadata (e.g. nr_frags) are updated in eBPF helpers
+	 * (e.g. bpf_xdp_adjust_tail), we need to update data_len here.
+	 */
+	if (xdp_buff_has_frags(xdp))
+		skb->data_len = skb_shinfo(skb)->xdp_frags_size;
+	else
+		skb->data_len = 0;
+
 	/* check if XDP changed eth hdr such SKB needs update */
 	eth = (struct ethhdr *)xdp->data;
 	if ((orig_eth_type != eth->h_proto) ||
@@ -4916,12 +4930,84 @@ u32 bpf_prog_run_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp,
 	return act;
 }
 
+static int netif_skb_segment_for_xdp(struct sk_buff **pskb)
+{
+	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
+	u32 size, truesize, len, max_head_size, off;
+	struct sk_buff *skb = *pskb, *nskb;
+	int err, i, head_off;
+	void *data;
+
+	max_head_size = SKB_WITH_OVERHEAD(PAGE_SIZE - XDP_PACKET_HEADROOM);
+	if (skb->len > max_head_size + MAX_SKB_FRAGS * PAGE_SIZE)
+		return -ENOMEM;
+
+	size = min_t(u32, skb->len, max_head_size);
+	truesize = SKB_HEAD_ALIGN(size) + XDP_PACKET_HEADROOM;
+	data = page_pool_dev_alloc_va(sd->page_pool, &truesize);
+	if (!data)
+		return -ENOMEM;
+
+	nskb = napi_build_skb(data, truesize);
+	if (!nskb) {
+		page_pool_free_va(sd->page_pool, data, true);
+		return -ENOMEM;
+	}
+
+	skb_reserve(nskb, XDP_PACKET_HEADROOM);
+	skb_copy_header(nskb, skb);
+	skb_mark_for_recycle(nskb);
+
+	err = skb_copy_bits(skb, 0, nskb->data, size);
+	if (err) {
+		consume_skb(nskb);
+		return err;
+	}
+	skb_put(nskb, size);
+
+	head_off = skb_headroom(nskb) - skb_headroom(skb);
+	skb_headers_offset_update(nskb, head_off);
+
+	off = size;
+	len = skb->len - off;
+	for (i = 0; i < MAX_SKB_FRAGS && off < skb->len; i++) {
+		struct page *page;
+		u32 page_off;
+
+		size = min_t(u32, len, PAGE_SIZE);
+		truesize = size;
+
+		page = page_pool_dev_alloc(sd->page_pool, &page_off,
+					   &truesize);
+		if (!data) {
+			consume_skb(nskb);
+			return -ENOMEM;
+		}
+
+		skb_add_rx_frag(nskb, i, page, page_off, size, truesize);
+		err = skb_copy_bits(skb, off, page_address(page) + page_off,
+				    size);
+		if (err) {
+			consume_skb(nskb);
+			return err;
+		}
+
+		len -= size;
+		off += size;
+	}
+
+	consume_skb(skb);
+	*pskb = nskb;
+
+	return 0;
+}
+
 static u32 netif_receive_generic_xdp(struct sk_buff **pskb,
 				     struct xdp_buff *xdp,
 				     struct bpf_prog *xdp_prog)
 {
 	struct sk_buff *skb = *pskb;
-	u32 act = XDP_DROP;
+	u32 mac_len, act = XDP_DROP;
 
 	/* Reinjected packets coming from act_mirred or similar should
 	 * not get XDP generic processing.
@@ -4929,12 +5015,10 @@ static u32 netif_receive_generic_xdp(struct sk_buff **pskb,
 	if (skb_is_redirected(skb))
 		return XDP_PASS;
 
-	/* XDP packets must be linear and must have sufficient headroom
-	 * of XDP_PACKET_HEADROOM bytes. This is the guarantee that also
-	 * native XDP provides, thus we need to do it here as well.
+	/* XDP does not support fraglist so we need to linearize
+	 * the skb.
 	 */
-	if (skb_cloned(skb) || skb_is_nonlinear(skb) ||
-	    skb_headroom(skb) < XDP_PACKET_HEADROOM) {
+	if (skb_has_frag_list(skb) || !xdp_prog->aux->xdp_has_frags) {
 		int hroom = XDP_PACKET_HEADROOM - skb_headroom(skb);
 		int troom = skb->tail + skb->data_len - skb->end;
 
@@ -4947,23 +5031,40 @@ static u32 netif_receive_generic_xdp(struct sk_buff **pskb,
 			goto do_drop;
 		if (skb_linearize(skb))
 			goto do_drop;
+
+		goto do_xdp;
 	}
 
-	act = bpf_prog_run_generic_xdp(skb, xdp, xdp_prog);
+	/* XDP packets must have sufficient headroom of XDP_PACKET_HEADROOM
+	 * bytes. This is the guarantee that also native XDP provides,
+	 * thus we need to do it here as well.
+	 */
+	mac_len = skb->data - skb_mac_header(skb);
+	__skb_push(skb, mac_len);
+
+	if (skb_cloned(skb) || skb_shinfo(skb)->nr_frags ||
+	    skb_headroom(skb) < XDP_PACKET_HEADROOM) {
+		if (netif_skb_segment_for_xdp(pskb))
+			goto do_drop;
+	}
+
+	__skb_pull(*pskb, mac_len);
+do_xdp:
+	act = bpf_prog_run_generic_xdp(*pskb, xdp, xdp_prog);
 	switch (act) {
 	case XDP_REDIRECT:
 	case XDP_TX:
 	case XDP_PASS:
 		break;
 	default:
-		bpf_warn_invalid_xdp_action(skb->dev, xdp_prog, act);
+		bpf_warn_invalid_xdp_action((*pskb)->dev, xdp_prog, act);
 		fallthrough;
 	case XDP_ABORTED:
-		trace_xdp_exception(skb->dev, xdp_prog, act);
+		trace_xdp_exception((*pskb)->dev, xdp_prog, act);
 		fallthrough;
 	case XDP_DROP:
 	do_drop:
-		kfree_skb(skb);
+		kfree_skb(*pskb);
 		break;
 	}
 
-- 
2.43.0

Re: [PATCH v4 net-next 1/3] net: introduce page_pool pointer in softnet_data percpu struct

[kernel test robot]

Hi Lorenzo,

kernel test robot noticed the following build errors:

[auto build test ERROR on net-next/main]

url:    https://github.com/intel-lab-lkp/linux/commits/Lorenzo-Bianconi/net-introduce-page_pool-pointer-in-softnet_data-percpu-struct/20231212-181103
base:   net-next/main
patch link:    https://lore.kernel.org/r/2a267c8f331996de0e26568472c45fe78eb67e1d.1702375338.git.lorenzo%40kernel.org
patch subject: [PATCH v4 net-next 1/3] net: introduce page_pool pointer in softnet_data percpu struct
config: um-allnoconfig (https://download.01.org/0day-ci/archive/20231213/202312130546.Kst7VY7F-lkp@intel.com/config)
compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project.git 4a5ac14ee968ff0ad5d2cc1ffa0299048db4c88a)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231213/202312130546.Kst7VY7F-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202312130546.Kst7VY7F-lkp@intel.com/

All errors (new ones prefixed by >>):

   /usr/bin/ld: init/main.o: warning: relocation in read-only section `.ref.text'
   /usr/bin/ld: warning: .tmp_vmlinux.kallsyms1 has a LOAD segment with RWX permissions
   /usr/bin/ld: net/core/dev.o: in function `net_dev_init':
>> net/core/dev.c:11734: undefined reference to `page_pool_create'
   /usr/bin/ld: warning: creating DT_TEXTREL in a PIE
   clang: error: linker command failed with exit code 1 (use -v to see invocation)


vim +11734 net/core/dev.c

 11667	
 11668	/*
 11669	 *	Initialize the DEV module. At boot time this walks the device list and
 11670	 *	unhooks any devices that fail to initialise (normally hardware not
 11671	 *	present) and leaves us with a valid list of present and active devices.
 11672	 *
 11673	 */
 11674	
 11675	#define SD_PAGE_POOL_RING_SIZE	256
 11676	/*
 11677	 *       This is called single threaded during boot, so no need
 11678	 *       to take the rtnl semaphore.
 11679	 */
 11680	static int __init net_dev_init(void)
 11681	{
 11682		struct softnet_data *sd;
 11683		int i, rc = -ENOMEM;
 11684	
 11685		BUG_ON(!dev_boot_phase);
 11686	
 11687		net_dev_struct_check();
 11688	
 11689		if (dev_proc_init())
 11690			goto out;
 11691	
 11692		if (netdev_kobject_init())
 11693			goto out;
 11694	
 11695		INIT_LIST_HEAD(&ptype_all);
 11696		for (i = 0; i < PTYPE_HASH_SIZE; i++)
 11697			INIT_LIST_HEAD(&ptype_base[i]);
 11698	
 11699		if (register_pernet_subsys(&netdev_net_ops))
 11700			goto out;
 11701	
 11702		/*
 11703		 *	Initialise the packet receive queues.
 11704		 */
 11705	
 11706		for_each_possible_cpu(i) {
 11707			struct work_struct *flush = per_cpu_ptr(&flush_works, i);
 11708			struct page_pool_params page_pool_params = {
 11709				.pool_size = SD_PAGE_POOL_RING_SIZE,
 11710				.nid = NUMA_NO_NODE,
 11711			};
 11712	
 11713			INIT_WORK(flush, flush_backlog);
 11714	
 11715			sd = &per_cpu(softnet_data, i);
 11716			skb_queue_head_init(&sd->input_pkt_queue);
 11717			skb_queue_head_init(&sd->process_queue);
 11718	#ifdef CONFIG_XFRM_OFFLOAD
 11719			skb_queue_head_init(&sd->xfrm_backlog);
 11720	#endif
 11721			INIT_LIST_HEAD(&sd->poll_list);
 11722			sd->output_queue_tailp = &sd->output_queue;
 11723	#ifdef CONFIG_RPS
 11724			INIT_CSD(&sd->csd, rps_trigger_softirq, sd);
 11725			sd->cpu = i;
 11726	#endif
 11727			INIT_CSD(&sd->defer_csd, trigger_rx_softirq, sd);
 11728			spin_lock_init(&sd->defer_lock);
 11729	
 11730			init_gro_hash(&sd->backlog);
 11731			sd->backlog.poll = process_backlog;
 11732			sd->backlog.weight = weight_p;
 11733	
 11734			sd->page_pool = page_pool_create(&page_pool_params);
 11735			if (IS_ERR(sd->page_pool)) {
 11736				sd->page_pool = NULL;
 11737				goto out;
 11738			}
 11739			page_pool_set_cpuid(sd->page_pool, i);
 11740		}
 11741	
 11742		dev_boot_phase = 0;
 11743	
 11744		/* The loopback device is special if any other network devices
 11745		 * is present in a network namespace the loopback device must
 11746		 * be present. Since we now dynamically allocate and free the
 11747		 * loopback device ensure this invariant is maintained by
 11748		 * keeping the loopback device as the first device on the
 11749		 * list of network devices.  Ensuring the loopback devices
 11750		 * is the first device that appears and the last network device
 11751		 * that disappears.
 11752		 */
 11753		if (register_pernet_device(&loopback_net_ops))
 11754			goto out;
 11755	
 11756		if (register_pernet_device(&default_device_ops))
 11757			goto out;
 11758	
 11759		open_softirq(NET_TX_SOFTIRQ, net_tx_action);
 11760		open_softirq(NET_RX_SOFTIRQ, net_rx_action);
 11761	
 11762		rc = cpuhp_setup_state_nocalls(CPUHP_NET_DEV_DEAD, "net/dev:dead",
 11763					       NULL, dev_cpu_dead);
 11764		WARN_ON(rc < 0);
 11765		rc = 0;
 11766	out:
 11767		if (rc < 0) {
 11768			for_each_possible_cpu(i) {
 11769				sd = &per_cpu(softnet_data, i);
 11770				if (!sd->page_pool)
 11771					continue;
 11772	
 11773				page_pool_destroy(sd->page_pool);
 11774				sd->page_pool = NULL;
 11775			}
 11776		}
 11777	
 11778		return rc;
 11779	}
 11780	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH v4 net-next 1/3] net: introduce page_pool pointer in softnet_data percpu struct

[kernel test robot]

Hi Lorenzo,

kernel test robot noticed the following build errors:

[auto build test ERROR on net-next/main]

url:    https://github.com/intel-lab-lkp/linux/commits/Lorenzo-Bianconi/net-introduce-page_pool-pointer-in-softnet_data-percpu-struct/20231212-181103
base:   net-next/main
patch link:    https://lore.kernel.org/r/2a267c8f331996de0e26568472c45fe78eb67e1d.1702375338.git.lorenzo%40kernel.org
patch subject: [PATCH v4 net-next 1/3] net: introduce page_pool pointer in softnet_data percpu struct
config: arc-defconfig (https://download.01.org/0day-ci/archive/20231213/202312130531.EIYsEYp0-lkp@intel.com/config)
compiler: arc-elf-gcc (GCC) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231213/202312130531.EIYsEYp0-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202312130531.EIYsEYp0-lkp@intel.com/

All errors (new ones prefixed by >>):

   arc-elf-ld: net/core/dev.o: in function `net_dev_init':
>> dev.c:(.init.text+0x180): undefined reference to `page_pool_create'
>> arc-elf-ld: dev.c:(.init.text+0x180): undefined reference to `page_pool_create'

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH v4 net-next 3/3] xdp: add multi-buff support for xdp running in generic mode

[kernel test robot]

Hi Lorenzo,

kernel test robot noticed the following build errors:

[auto build test ERROR on net-next/main]

url:    https://github.com/intel-lab-lkp/linux/commits/Lorenzo-Bianconi/net-introduce-page_pool-pointer-in-softnet_data-percpu-struct/20231212-181103
base:   net-next/main
patch link:    https://lore.kernel.org/r/2d0f9388c6509192d88e359a402517a73124b50e.1702375338.git.lorenzo%40kernel.org
patch subject: [PATCH v4 net-next 3/3] xdp: add multi-buff support for xdp running in generic mode
config: sh-edosk7760_defconfig (https://download.01.org/0day-ci/archive/20231213/202312130625.4PfR5846-lkp@intel.com/config)
compiler: sh4-linux-gcc (GCC) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231213/202312130625.4PfR5846-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202312130625.4PfR5846-lkp@intel.com/

All errors (new ones prefixed by >>):

   sh4-linux-ld: net/core/dev.o: in function `netif_skb_segment_for_xdp':
>> net/core/dev.c:5003:(.text+0x2860): undefined reference to `page_pool_alloc_frag'
>> sh4-linux-ld: net/core/dev.c:5003:(.text+0x28fc): undefined reference to `page_pool_alloc_pages'
   sh4-linux-ld: net/core/dev.o: in function `net_dev_init':
   net/core/dev.c:11882:(.init.text+0x198): undefined reference to `page_pool_create'


vim +5003 net/core/dev.c

  4932	
  4933	static int netif_skb_segment_for_xdp(struct sk_buff **pskb)
  4934	{
  4935		struct softnet_data *sd = this_cpu_ptr(&softnet_data);
  4936		u32 size, truesize, len, max_head_size, off;
  4937		struct sk_buff *skb = *pskb, *nskb;
  4938		int err, i, head_off;
  4939		void *data;
  4940	
  4941		max_head_size = SKB_WITH_OVERHEAD(PAGE_SIZE - XDP_PACKET_HEADROOM);
  4942		if (skb->len > max_head_size + MAX_SKB_FRAGS * PAGE_SIZE)
  4943			return -ENOMEM;
  4944	
  4945		size = min_t(u32, skb->len, max_head_size);
  4946		truesize = SKB_HEAD_ALIGN(size) + XDP_PACKET_HEADROOM;
  4947		data = page_pool_dev_alloc_va(sd->page_pool, &truesize);
  4948		if (!data)
  4949			return -ENOMEM;
  4950	
  4951		nskb = napi_build_skb(data, truesize);
  4952		if (!nskb) {
  4953			page_pool_free_va(sd->page_pool, data, true);
  4954			return -ENOMEM;
  4955		}
  4956	
  4957		skb_reserve(nskb, XDP_PACKET_HEADROOM);
  4958		skb_copy_header(nskb, skb);
  4959		skb_mark_for_recycle(nskb);
  4960	
  4961		err = skb_copy_bits(skb, 0, nskb->data, size);
  4962		if (err) {
  4963			consume_skb(nskb);
  4964			return err;
  4965		}
  4966		skb_put(nskb, size);
  4967	
  4968		head_off = skb_headroom(nskb) - skb_headroom(skb);
  4969		skb_headers_offset_update(nskb, head_off);
  4970	
  4971		off = size;
  4972		len = skb->len - off;
  4973		for (i = 0; i < MAX_SKB_FRAGS && off < skb->len; i++) {
  4974			struct page *page;
  4975			u32 page_off;
  4976	
  4977			size = min_t(u32, len, PAGE_SIZE);
  4978			truesize = size;
  4979	
  4980			page = page_pool_dev_alloc(sd->page_pool, &page_off,
  4981						   &truesize);
  4982			if (!data) {
  4983				consume_skb(nskb);
  4984				return -ENOMEM;
  4985			}
  4986	
  4987			skb_add_rx_frag(nskb, i, page, page_off, size, truesize);
  4988			err = skb_copy_bits(skb, off, page_address(page) + page_off,
  4989					    size);
  4990			if (err) {
  4991				consume_skb(nskb);
  4992				return err;
  4993			}
  4994	
  4995			len -= size;
  4996			off += size;
  4997		}
  4998	
  4999		consume_skb(skb);
  5000		*pskb = nskb;
  5001	
  5002		return 0;
> 5003	}
  5004	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki