[PATCH net-next 0/2] Indirect dev ingress qdisc creation order

[PATCH net-next 0/2] Indirect dev ingress qdisc creation order

[Eli Cohen]

The first patch is just a cleanup of the code.
The second patch is fixing the dependency in ingress qdisc creation
relative to offloading driver registration to filter configurations.

Eli Cohen (2):
  net/core: Remove unused field from struct flow_indr_dev
  net: Fix offloading indirect devices dependency on qdisc order
    creation

 include/net/flow_offload.h            |  1 +
 net/core/flow_offload.c               | 92 ++++++++++++++++++++++++++-
 net/netfilter/nf_flow_table_offload.c |  1 +
 net/netfilter/nf_tables_offload.c     |  1 +
 net/sched/cls_api.c                   |  1 +
 5 files changed, 94 insertions(+), 2 deletions(-)

-- 
2.32.0

[PATCH net-next 1/2] net/core: Remove unused field from struct flow_indr_dev

[Eli Cohen]

rcu field is not used. Remove it.

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Eli Cohen <elic@nvidia.com>
---
 net/core/flow_offload.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/net/core/flow_offload.c b/net/core/flow_offload.c
index 715b67f6c62f..1da83997e86a 100644
--- a/net/core/flow_offload.c
+++ b/net/core/flow_offload.c
@@ -327,7 +327,6 @@ struct flow_indr_dev {
 	flow_indr_block_bind_cb_t	*cb;
 	void				*cb_priv;
 	refcount_t			refcnt;
-	struct rcu_head			rcu;
 };
 
 static struct flow_indr_dev *flow_indr_dev_alloc(flow_indr_block_bind_cb_t *cb,
-- 
2.32.0

[PATCH net-next 2/2] net: Fix offloading indirect devices dependency on qdisc order creation

[Eli Cohen]

Currently, when creating an ingress qdisc on an indirect device before
the driver registered for callbacks, the driver will not have a chance
to register its filter configuration callbacks.

To fix that, modify the code such that it keeps track of all the ingress
qdiscs that call flow_indr_dev_setup_offload(). When a driver calls
flow_indr_dev_register(),  go through the list of tracked ingress qdiscs
and call the driver callback entry point so as to give it a chance to
register its callback.

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Eli Cohen <elic@nvidia.com>
---
 include/net/flow_offload.h            |  1 +
 net/core/flow_offload.c               | 91 ++++++++++++++++++++++++++-
 net/netfilter/nf_flow_table_offload.c |  1 +
 net/netfilter/nf_tables_offload.c     |  1 +
 net/sched/cls_api.c                   |  1 +
 5 files changed, 94 insertions(+), 1 deletion(-)

diff --git a/include/net/flow_offload.h b/include/net/flow_offload.h
index f3c2841566a0..5aa27acdb0b3 100644
--- a/include/net/flow_offload.h
+++ b/include/net/flow_offload.h
@@ -453,6 +453,7 @@ struct flow_block_offload {
 	struct list_head *driver_block_list;
 	struct netlink_ext_ack *extack;
 	struct Qdisc *sch;
+	struct list_head *cb_list_head;
 };
 
 enum tc_setup_type;
diff --git a/net/core/flow_offload.c b/net/core/flow_offload.c
index 1da83997e86a..81a504d88e63 100644
--- a/net/core/flow_offload.c
+++ b/net/core/flow_offload.c
@@ -321,6 +321,7 @@ EXPORT_SYMBOL(flow_block_cb_setup_simple);
 static DEFINE_MUTEX(flow_indr_block_lock);
 static LIST_HEAD(flow_block_indr_list);
 static LIST_HEAD(flow_block_indr_dev_list);
+static LIST_HEAD(flow_indir_dev_list);
 
 struct flow_indr_dev {
 	struct list_head		list;
@@ -345,6 +346,35 @@ static struct flow_indr_dev *flow_indr_dev_alloc(flow_indr_block_bind_cb_t *cb,
 	return indr_dev;
 }
 
+struct flow_indir_dev_info {
+	void *data;
+	struct net_device *dev;
+	struct Qdisc *sch;
+	enum tc_setup_type type;
+	void (*cleanup)(struct flow_block_cb *block_cb);
+	struct list_head list;
+	enum flow_block_command command;
+	enum flow_block_binder_type binder_type;
+	struct list_head *cb_list;
+};
+
+static void existing_qdiscs_register(flow_indr_block_bind_cb_t *cb, void *cb_priv)
+{
+	struct flow_block_offload bo;
+	struct flow_indir_dev_info *cur;
+	struct tcf_block *block;
+
+	list_for_each_entry(cur, &flow_indir_dev_list, list) {
+		memset(&bo, 0, sizeof(bo));
+		bo.command = cur->command;
+		bo.binder_type = cur->binder_type;
+		block = cur->data;
+		INIT_LIST_HEAD(&bo.cb_list);
+		cb(cur->dev, cur->sch, cb_priv, cur->type, &bo, cur->data, cur->cleanup);
+		list_splice(&bo.cb_list, cur->cb_list);
+	}
+}
+
 int flow_indr_dev_register(flow_indr_block_bind_cb_t *cb, void *cb_priv)
 {
 	struct flow_indr_dev *indr_dev;
@@ -366,6 +396,7 @@ int flow_indr_dev_register(flow_indr_block_bind_cb_t *cb, void *cb_priv)
 	}
 
 	list_add(&indr_dev->list, &flow_block_indr_dev_list);
+	existing_qdiscs_register(cb, cb_priv);
 	mutex_unlock(&flow_indr_block_lock);
 
 	return 0;
@@ -462,7 +493,59 @@ struct flow_block_cb *flow_indr_block_cb_alloc(flow_setup_cb_t *cb,
 }
 EXPORT_SYMBOL(flow_indr_block_cb_alloc);
 
-int flow_indr_dev_setup_offload(struct net_device *dev, struct Qdisc *sch,
+static struct flow_indir_dev_info *find_indir_dev(void *data)
+{
+	struct flow_indir_dev_info *cur;
+
+	list_for_each_entry(cur, &flow_indir_dev_list, list) {
+		if (cur->data == data)
+			return cur;
+	}
+	return NULL;
+}
+
+static int indir_dev_add(void *data, struct net_device *dev, struct Qdisc *sch,
+			 enum tc_setup_type type, void (*cleanup)(struct flow_block_cb *block_cb),
+			 struct flow_block_offload *bo)
+{
+	struct flow_indir_dev_info *info;
+
+	info = find_indir_dev(data);
+	if (info)
+		return -EEXIST;
+
+	info = kzalloc(sizeof(*info), GFP_KERNEL);
+	if (!info)
+		return -ENOMEM;
+
+	info->data = data;
+	info->dev = dev;
+	info->sch = sch;
+	info->type = type;
+	info->cleanup = cleanup;
+	info->command = bo->command;
+	info->binder_type = bo->binder_type;
+	info->cb_list = bo->cb_list_head;
+
+	list_add(&info->list, &flow_indir_dev_list);
+	return 0;
+}
+
+static int indir_dev_remove(void *data)
+{
+	struct flow_indir_dev_info *info;
+
+	info = find_indir_dev(data);
+	if (!info)
+		return -ENOENT;
+
+	list_del(&info->list);
+
+	kfree(info);
+	return 0;
+}
+
+int flow_indr_dev_setup_offload(struct net_device *dev,	struct Qdisc *sch,
 				enum tc_setup_type type, void *data,
 				struct flow_block_offload *bo,
 				void (*cleanup)(struct flow_block_cb *block_cb))
@@ -470,6 +553,12 @@ int flow_indr_dev_setup_offload(struct net_device *dev, struct Qdisc *sch,
 	struct flow_indr_dev *this;
 
 	mutex_lock(&flow_indr_block_lock);
+
+	if (bo->command == FLOW_BLOCK_BIND)
+		indir_dev_add(data, dev, sch, type, cleanup, bo);
+	else if (bo->command == FLOW_BLOCK_UNBIND)
+		indir_dev_remove(data);
+
 	list_for_each_entry(this, &flow_block_indr_dev_list, list)
 		this->cb(dev, sch, this->cb_priv, type, bo, data, cleanup);
 
diff --git a/net/netfilter/nf_flow_table_offload.c b/net/netfilter/nf_flow_table_offload.c
index f92006cec94c..cbd9f59098b7 100644
--- a/net/netfilter/nf_flow_table_offload.c
+++ b/net/netfilter/nf_flow_table_offload.c
@@ -1097,6 +1097,7 @@ static void nf_flow_table_block_offload_init(struct flow_block_offload *bo,
 	bo->command	= cmd;
 	bo->binder_type	= FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS;
 	bo->extack	= extack;
+	bo->cb_list_head = &flowtable->flow_block.cb_list;
 	INIT_LIST_HEAD(&bo->cb_list);
 }
 
diff --git a/net/netfilter/nf_tables_offload.c b/net/netfilter/nf_tables_offload.c
index b58d73a96523..9656c1646222 100644
--- a/net/netfilter/nf_tables_offload.c
+++ b/net/netfilter/nf_tables_offload.c
@@ -353,6 +353,7 @@ static void nft_flow_block_offload_init(struct flow_block_offload *bo,
 	bo->command	= cmd;
 	bo->binder_type	= FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS;
 	bo->extack	= extack;
+	bo->cb_list_head = &basechain->flow_block.cb_list;
 	INIT_LIST_HEAD(&bo->cb_list);
 }
 
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index e3e79e9bd706..9b276d14be4c 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -634,6 +634,7 @@ static void tcf_block_offload_init(struct flow_block_offload *bo,
 	bo->block_shared = shared;
 	bo->extack = extack;
 	bo->sch = sch;
+	bo->cb_list_head = &flow_block->cb_list;
 	INIT_LIST_HEAD(&bo->cb_list);
 }
 
-- 
2.32.0

Re: [PATCH net-next 2/2] net: Fix offloading indirect devices dependency on qdisc order creation

[Jakub Kicinski]

On Tue, 17 Aug 2021 16:22:17 +0300 Eli Cohen wrote:
> Currently, when creating an ingress qdisc on an indirect device before
> the driver registered for callbacks, the driver will not have a chance
> to register its filter configuration callbacks.
> 
> To fix that, modify the code such that it keeps track of all the ingress
> qdiscs that call flow_indr_dev_setup_offload(). When a driver calls
> flow_indr_dev_register(),  go through the list of tracked ingress qdiscs
> and call the driver callback entry point so as to give it a chance to
> register its callback.
> 
> Reviewed-by: Jiri Pirko <jiri@nvidia.com>
> Signed-off-by: Eli Cohen <elic@nvidia.com>

net/core/flow_offload.c: In function ‘existing_qdiscs_register’:
net/core/flow_offload.c:365:20: warning: variable ‘block’ set but not used [-Wunused-but-set-variable]
  365 |  struct tcf_block *block;
      |                    ^~~~~

Re: [PATCH net-next 2/2] net: Fix offloading indirect devices dependency on qdisc order creation

[Eli Cohen]

On Tue, Aug 17, 2021 at 07:00:41AM -0700, Jakub Kicinski wrote:
> On Tue, 17 Aug 2021 16:22:17 +0300 Eli Cohen wrote:
> > Currently, when creating an ingress qdisc on an indirect device before
> > the driver registered for callbacks, the driver will not have a chance
> > to register its filter configuration callbacks.
> > 
> > To fix that, modify the code such that it keeps track of all the ingress
> > qdiscs that call flow_indr_dev_setup_offload(). When a driver calls
> > flow_indr_dev_register(),  go through the list of tracked ingress qdiscs
> > and call the driver callback entry point so as to give it a chance to
> > register its callback.
> > 
> > Reviewed-by: Jiri Pirko <jiri@nvidia.com>
> > Signed-off-by: Eli Cohen <elic@nvidia.com>
> 
> net/core/flow_offload.c: In function ‘existing_qdiscs_register’:
> net/core/flow_offload.c:365:20: warning: variable ‘block’ set but not used [-Wunused-but-set-variable]
>   365 |  struct tcf_block *block;
>       |                    ^~~~~

Thanks Jakub.
Would you mind telling me how you invoked the compiler to catch this?

Re: [PATCH net-next 2/2] net: Fix offloading indirect devices dependency on qdisc order creation

[Jakub Kicinski]

On Tue, 17 Aug 2021 17:30:09 +0300 Eli Cohen wrote:
> On Tue, Aug 17, 2021 at 07:00:41AM -0700, Jakub Kicinski wrote:
> > On Tue, 17 Aug 2021 16:22:17 +0300 Eli Cohen wrote:  
> > > Currently, when creating an ingress qdisc on an indirect device before
> > > the driver registered for callbacks, the driver will not have a chance
> > > to register its filter configuration callbacks.
> > > 
> > > To fix that, modify the code such that it keeps track of all the ingress
> > > qdiscs that call flow_indr_dev_setup_offload(). When a driver calls
> > > flow_indr_dev_register(),  go through the list of tracked ingress qdiscs
> > > and call the driver callback entry point so as to give it a chance to
> > > register its callback.
> > > 
> > > Reviewed-by: Jiri Pirko <jiri@nvidia.com>
> > > Signed-off-by: Eli Cohen <elic@nvidia.com>  
> > 
> > net/core/flow_offload.c: In function ‘existing_qdiscs_register’:
> > net/core/flow_offload.c:365:20: warning: variable ‘block’ set but not used [-Wunused-but-set-variable]
> >   365 |  struct tcf_block *block;
> >       |                    ^~~~~  
> 
> Thanks Jakub.
> Would you mind telling me how you invoked the compiler to catch this?

make W=1

Re: [PATCH net-next 2/2] net: Fix offloading indirect devices dependency on qdisc order creation

[kernel test robot]

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Hi Eli,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on net-next/master]

url:    https://github.com/0day-ci/linux/commits/Eli-Cohen/Indirect-dev-ingress-qdisc-creation-order/20210817-212524
base:   https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git 752be2976405b7499890c0b6bac6d30d34d08bd6
config: x86_64-randconfig-a011-20210816 (attached as .config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 2c6448cdc2f68f8c28fd0bd9404182b81306e6e6)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/8e304f96c15799e4618967e3a19cfd25fc9868de
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Eli-Cohen/Indirect-dev-ingress-qdisc-creation-order/20210817-212524
        git checkout 8e304f96c15799e4618967e3a19cfd25fc9868de
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> net/core/flow_offload.c:365:20: warning: variable 'block' set but not used [-Wunused-but-set-variable]
           struct tcf_block *block;
                             ^
   1 warning generated.


vim +/block +365 net/core/flow_offload.c

   360	
   361	static void existing_qdiscs_register(flow_indr_block_bind_cb_t *cb, void *cb_priv)
   362	{
   363		struct flow_block_offload bo;
   364		struct flow_indir_dev_info *cur;
 > 365		struct tcf_block *block;
   366	
   367		list_for_each_entry(cur, &flow_indir_dev_list, list) {
   368			memset(&bo, 0, sizeof(bo));
   369			bo.command = cur->command;
   370			bo.binder_type = cur->binder_type;
   371			block = cur->data;
   372			INIT_LIST_HEAD(&bo.cb_list);
   373			cb(cur->dev, cur->sch, cb_priv, cur->type, &bo, cur->data, cur->cleanup);
   374			list_splice(&bo.cb_list, cur->cb_list);
   375		}
   376	}
   377	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

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