[PATCH net-next 0/9] mlx5 devlink mutex removal part 1

[PATCH net-next 0/9] mlx5 devlink mutex removal part 1

[Saeed Mahameed]

From: Saeed Mahameed <saeedm@nvidia.com>

Moshe Shemesh Says:
===================
1) Fix devlink lock in mlx5 devlink eswitch callbacks

Following the commit 14e426bf1a4d "devlink: hold the instance lock
during eswitch_mode callbacks" which takes devlink instance lock for all
devlink eswitch callbacks and adds a temporary workaround, this patchset
removes the workaround, replaces devlink API functions by devl_ API
where called from mlx5 driver eswitch callbacks flows and adds devlink
instance lock in other driver's path that leads to these functions.
While moving to devl_ API the patchset removes part of the devlink API
functions which mlx5 was the last one to use and so not used by any
driver now.

The patchset also remove DEVLINK_NL_FLAG_NO_LOCK flag from the callbacks
of port_new/port which are called only from mlx5 driver and the already
locked by the patchset as parallel paths to the eswitch callbacks using
devl_ API functions.

This patchset will be followed by another patchset that will remove
DEVLINK_NL_FLAG_NO_LOCK flag from devlink reload and devlink health
callbacks. Thus we will have all devlink callbacks locked and it will
pave the way to remove devlink mutex.
=================== 

Moshe Shemesh (9):
  net/mlx5: Remove devl_unlock from mlx5_eswtich_mode_callback_enter
  net/mlx5: Use devl_ API for rate nodes destroy
  devlink: Remove unused function devlink_rate_nodes_destroy
  net/mlx5: Use devl_ API in mlx5_esw_offloads_devlink_port_register
  net/mlx5: Use devl_ API in mlx5_esw_devlink_sf_port_register
  devlink: Remove unused functions devlink_rate_leaf_create/destroy
  net/mlx5: Use devl_ API in mlx5e_devlink_port_register
  net/mlx5: Remove devl_unlock from mlx5_devlink_eswitch_mode_set
  devlink: Hold the instance lock in port_new / port_del callbacks

 drivers/net/ethernet/mellanox/mlx5/core/dev.c | 29 +++++++-
 .../ethernet/mellanox/mlx5/core/en/devlink.c  | 16 ++++-
 .../mellanox/mlx5/core/esw/devlink_port.c     | 20 +++---
 .../net/ethernet/mellanox/mlx5/core/eswitch.c | 18 ++++-
 .../mellanox/mlx5/core/eswitch_offloads.c     | 57 +++++-----------
 include/linux/mlx5/driver.h                   |  4 ++
 include/net/devlink.h                         |  3 -
 net/core/devlink.c                            | 66 +++----------------
 8 files changed, 94 insertions(+), 119 deletions(-)

-- 
2.36.1

[PATCH net-next 1/9] net/mlx5: Remove devl_unlock from mlx5_eswtich_mode_callback_enter

[Saeed Mahameed]

From: Moshe Shemesh <moshe@nvidia.com>

The function mlx5_eswtich_mode_callback_enter() was added as a temporary
workaround once devlink instance lock was added to devlink eswitch
callbacks. However, code review and testing show that all the callbacks
part to eswitch_mode_set don't take devlink instance lock in any flow
and so unlocking devlink instance lock while entering these functions is
not needed.

Remove devl_lock from mlx5_eswtich_mode_callback_enter() and devl_unlock
from mlx5_eswtich_mode_callback_exit(). Also remove the functions
mlx5_eswtich_mode_callback_enter()/exit() as they are not needed any
more. The callback eswitch_mode_set will be treated separately in the
following patches.

Signed-off-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
---
 .../mellanox/mlx5/core/eswitch_offloads.c     | 43 +++++--------------
 1 file changed, 11 insertions(+), 32 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
index e224ec7005a6..3bd843e6d66a 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
@@ -3342,27 +3342,6 @@ static int esw_inline_mode_to_devlink(u8 mlx5_mode, u8 *mode)
 	return 0;
 }
 
-/* FIXME: devl_unlock() followed by devl_lock() inside driver callback
- * is never correct and prone to races. It's a transitional workaround,
- * never repeat this pattern.
- *
- * This code MUST be fixed before removing devlink_mutex as it is safe
- * to do only because of that mutex.
- */
-static void mlx5_eswtich_mode_callback_enter(struct devlink *devlink,
-					     struct mlx5_eswitch *esw)
-{
-	devl_unlock(devlink);
-	down_write(&esw->mode_lock);
-}
-
-static void mlx5_eswtich_mode_callback_exit(struct devlink *devlink,
-					    struct mlx5_eswitch *esw)
-{
-	up_write(&esw->mode_lock);
-	devl_lock(devlink);
-}
-
 int mlx5_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode,
 				  struct netlink_ext_ack *extack)
 {
@@ -3431,9 +3410,9 @@ int mlx5_devlink_eswitch_mode_get(struct devlink *devlink, u16 *mode)
 	if (IS_ERR(esw))
 		return PTR_ERR(esw);
 
-	mlx5_eswtich_mode_callback_enter(devlink, esw);
+	down_write(&esw->mode_lock);
 	err = esw_mode_to_devlink(esw->mode, mode);
-	mlx5_eswtich_mode_callback_exit(devlink, esw);
+	up_write(&esw->mode_lock);
 	return err;
 }
 
@@ -3480,7 +3459,7 @@ int mlx5_devlink_eswitch_inline_mode_set(struct devlink *devlink, u8 mode,
 	if (IS_ERR(esw))
 		return PTR_ERR(esw);
 
-	mlx5_eswtich_mode_callback_enter(devlink, esw);
+	down_write(&esw->mode_lock);
 
 	switch (MLX5_CAP_ETH(dev, wqe_inline_mode)) {
 	case MLX5_CAP_INLINE_MODE_NOT_REQUIRED:
@@ -3514,11 +3493,11 @@ int mlx5_devlink_eswitch_inline_mode_set(struct devlink *devlink, u8 mode,
 		goto out;
 
 	esw->offloads.inline_mode = mlx5_mode;
-	mlx5_eswtich_mode_callback_exit(devlink, esw);
+	up_write(&esw->mode_lock);
 	return 0;
 
 out:
-	mlx5_eswtich_mode_callback_exit(devlink, esw);
+	up_write(&esw->mode_lock);
 	return err;
 }
 
@@ -3531,9 +3510,9 @@ int mlx5_devlink_eswitch_inline_mode_get(struct devlink *devlink, u8 *mode)
 	if (IS_ERR(esw))
 		return PTR_ERR(esw);
 
-	mlx5_eswtich_mode_callback_enter(devlink, esw);
+	down_write(&esw->mode_lock);
 	err = esw_inline_mode_to_devlink(esw->offloads.inline_mode, mode);
-	mlx5_eswtich_mode_callback_exit(devlink, esw);
+	up_write(&esw->mode_lock);
 	return err;
 }
 
@@ -3549,7 +3528,7 @@ int mlx5_devlink_eswitch_encap_mode_set(struct devlink *devlink,
 	if (IS_ERR(esw))
 		return PTR_ERR(esw);
 
-	mlx5_eswtich_mode_callback_enter(devlink, esw);
+	down_write(&esw->mode_lock);
 
 	if (encap != DEVLINK_ESWITCH_ENCAP_MODE_NONE &&
 	    (!MLX5_CAP_ESW_FLOWTABLE_FDB(dev, reformat) ||
@@ -3592,7 +3571,7 @@ int mlx5_devlink_eswitch_encap_mode_set(struct devlink *devlink,
 	}
 
 unlock:
-	mlx5_eswtich_mode_callback_exit(devlink, esw);
+	up_write(&esw->mode_lock);
 	return err;
 }
 
@@ -3605,9 +3584,9 @@ int mlx5_devlink_eswitch_encap_mode_get(struct devlink *devlink,
 	if (IS_ERR(esw))
 		return PTR_ERR(esw);
 
-	mlx5_eswtich_mode_callback_enter(devlink, esw);
+	down_write(&esw->mode_lock);
 	*encap = esw->offloads.encap;
-	mlx5_eswtich_mode_callback_exit(devlink, esw);
+	up_write(&esw->mode_lock);
 	return 0;
 }
 
-- 
2.36.1

[PATCH net-next 2/9] net/mlx5: Use devl_ API for rate nodes destroy

[Saeed Mahameed]

From: Moshe Shemesh <moshe@nvidia.com>

Use devl_rate_nodes_destroy() instead of devlink_rate_nodes_destroy().
Add devlink instance lock in the driver paths to this function to have
it locked while calling devl_ API function.

This will be used by the downstream patch to invoke
mlx5_devlink_eswitch_mode_set() with devlink lock held.

Signed-off-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
---
 drivers/net/ethernet/mellanox/mlx5/core/eswitch.c  | 14 ++++++++++++--
 .../ethernet/mellanox/mlx5/core/eswitch_offloads.c |  2 ++
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
index b938632f89ff..571114e4878f 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
@@ -1330,9 +1330,13 @@ int mlx5_eswitch_enable(struct mlx5_eswitch *esw, int num_vfs)
 /* When disabling sriov, free driver level resources. */
 void mlx5_eswitch_disable_sriov(struct mlx5_eswitch *esw, bool clear_vf)
 {
+	struct devlink *devlink;
+
 	if (!mlx5_esw_allowed(esw))
 		return;
 
+	devlink = priv_to_devlink(esw->dev);
+	devl_lock(devlink);
 	down_write(&esw->mode_lock);
 	/* If driver is unloaded, this function is called twice by remove_one()
 	 * and mlx5_unload(). Prevent the second call.
@@ -1354,13 +1358,14 @@ void mlx5_eswitch_disable_sriov(struct mlx5_eswitch *esw, bool clear_vf)
 		struct devlink *devlink = priv_to_devlink(esw->dev);
 
 		esw_offloads_del_send_to_vport_meta_rules(esw);
-		devlink_rate_nodes_destroy(devlink);
+		devl_rate_nodes_destroy(devlink);
 	}
 
 	esw->esw_funcs.num_vfs = 0;
 
 unlock:
 	up_write(&esw->mode_lock);
+	devl_unlock(devlink);
 }
 
 /* Free resources for corresponding eswitch mode. It is called by devlink
@@ -1389,18 +1394,23 @@ void mlx5_eswitch_disable_locked(struct mlx5_eswitch *esw)
 	mlx5_esw_acls_ns_cleanup(esw);
 
 	if (esw->mode == MLX5_ESWITCH_OFFLOADS)
-		devlink_rate_nodes_destroy(devlink);
+		devl_rate_nodes_destroy(devlink);
 }
 
 void mlx5_eswitch_disable(struct mlx5_eswitch *esw)
 {
+	struct devlink *devlink;
+
 	if (!mlx5_esw_allowed(esw))
 		return;
 
 	mlx5_lag_disable_change(esw->dev);
+	devlink = priv_to_devlink(esw->dev);
+	devl_lock(devlink);
 	down_write(&esw->mode_lock);
 	mlx5_eswitch_disable_locked(esw);
 	up_write(&esw->mode_lock);
+	devl_unlock(devlink);
 	mlx5_lag_enable_change(esw->dev);
 }
 
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
index 3bd843e6d66a..f1640e4cb719 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
@@ -3377,7 +3377,9 @@ int mlx5_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode,
 	if (cur_mlx5_mode == mlx5_mode)
 		goto unlock;
 
+	devl_lock(devlink);
 	mlx5_eswitch_disable_locked(esw);
+	devl_unlock(devlink);
 	if (mode == DEVLINK_ESWITCH_MODE_SWITCHDEV) {
 		if (mlx5_devlink_trap_get_num_active(esw->dev)) {
 			NL_SET_ERR_MSG_MOD(extack,
-- 
2.36.1

[PATCH net-next 3/9] devlink: Remove unused function devlink_rate_nodes_destroy

[Saeed Mahameed]

From: Moshe Shemesh <moshe@nvidia.com>

The previous patch removed the last usage of the function
devlink_rate_nodes_destroy(). Thus, remove this function from devlink
API.

Signed-off-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
---
 include/net/devlink.h |  1 -
 net/core/devlink.c    | 18 ------------------
 2 files changed, 19 deletions(-)

diff --git a/include/net/devlink.h b/include/net/devlink.h
index 2a2a2a0c93f7..0e163cc87d45 100644
--- a/include/net/devlink.h
+++ b/include/net/devlink.h
@@ -1571,7 +1571,6 @@ void devlink_port_attrs_pci_sf_set(struct devlink_port *devlink_port,
 				   bool external);
 int devlink_rate_leaf_create(struct devlink_port *port, void *priv);
 void devlink_rate_leaf_destroy(struct devlink_port *devlink_port);
-void devlink_rate_nodes_destroy(struct devlink *devlink);
 void devlink_port_linecard_set(struct devlink_port *devlink_port,
 			       struct devlink_linecard *linecard);
 struct devlink_linecard *
diff --git a/net/core/devlink.c b/net/core/devlink.c
index db61f3a341cb..1588e2246234 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -10095,24 +10095,6 @@ void devl_rate_nodes_destroy(struct devlink *devlink)
 }
 EXPORT_SYMBOL_GPL(devl_rate_nodes_destroy);
 
-/**
- * devlink_rate_nodes_destroy - destroy all devlink rate nodes on device
- *
- * @devlink: devlink instance
- *
- * Unset parent for all rate objects and destroy all rate nodes
- * on specified device.
- *
- * Context: Takes and release devlink->lock <mutex>.
- */
-void devlink_rate_nodes_destroy(struct devlink *devlink)
-{
-	mutex_lock(&devlink->lock);
-	devl_rate_nodes_destroy(devlink);
-	mutex_unlock(&devlink->lock);
-}
-EXPORT_SYMBOL_GPL(devlink_rate_nodes_destroy);
-
 /**
  *	devlink_port_linecard_set - Link port with a linecard
  *
-- 
2.36.1

[PATCH net-next 4/9] net/mlx5: Use devl_ API in mlx5_esw_offloads_devlink_port_register

[Saeed Mahameed]

From: Moshe Shemesh <moshe@nvidia.com>

The function mlx5_esw_offloads_devlink_port_register() calls
devlink_port_register() and devlink_rate_leaf_create(). Use devl_ API to
call devl_port_register() and devl_rate_leaf_create() accordingly and
add devlink instance lock in driver paths to this function.

Similarly, use devl_ API to call devl_port_unregister() and
devl_rate_leaf_destroy() in mlx5_esw_offloads_devlink_port_unregister()
and ensure locking devlink instance lock on the paths to this function
too.

This will be used by the downstream patch to invoke
mlx5_devlink_eswitch_mode_set() with devlink lock held.

Signed-off-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
---
 .../net/ethernet/mellanox/mlx5/core/esw/devlink_port.c | 10 +++++-----
 drivers/net/ethernet/mellanox/mlx5/core/eswitch.c      |  4 ++++
 .../net/ethernet/mellanox/mlx5/core/eswitch_offloads.c | 10 ++++++++++
 3 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/esw/devlink_port.c b/drivers/net/ethernet/mellanox/mlx5/core/esw/devlink_port.c
index 7f9b96d9537e..a8f7618831f5 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/esw/devlink_port.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/esw/devlink_port.c
@@ -87,11 +87,11 @@ int mlx5_esw_offloads_devlink_port_register(struct mlx5_eswitch *esw, u16 vport_
 
 	devlink = priv_to_devlink(dev);
 	dl_port_index = mlx5_esw_vport_to_devlink_port_index(dev, vport_num);
-	err = devlink_port_register(devlink, dl_port, dl_port_index);
+	err = devl_port_register(devlink, dl_port, dl_port_index);
 	if (err)
 		goto reg_err;
 
-	err = devlink_rate_leaf_create(dl_port, vport);
+	err = devl_rate_leaf_create(dl_port, vport);
 	if (err)
 		goto rate_err;
 
@@ -99,7 +99,7 @@ int mlx5_esw_offloads_devlink_port_register(struct mlx5_eswitch *esw, u16 vport_
 	return 0;
 
 rate_err:
-	devlink_port_unregister(dl_port);
+	devl_port_unregister(dl_port);
 reg_err:
 	mlx5_esw_dl_port_free(dl_port);
 	return err;
@@ -118,10 +118,10 @@ void mlx5_esw_offloads_devlink_port_unregister(struct mlx5_eswitch *esw, u16 vpo
 
 	if (vport->dl_port->devlink_rate) {
 		mlx5_esw_qos_vport_update_group(esw, vport, NULL, NULL);
-		devlink_rate_leaf_destroy(vport->dl_port);
+		devl_rate_leaf_destroy(vport->dl_port);
 	}
 
-	devlink_port_unregister(vport->dl_port);
+	devl_port_unregister(vport->dl_port);
 	mlx5_esw_dl_port_free(vport->dl_port);
 	vport->dl_port = NULL;
 }
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
index 571114e4878f..b95f75431882 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
@@ -1296,6 +1296,7 @@ int mlx5_eswitch_enable_locked(struct mlx5_eswitch *esw, int num_vfs)
  */
 int mlx5_eswitch_enable(struct mlx5_eswitch *esw, int num_vfs)
 {
+	struct devlink *devlink;
 	bool toggle_lag;
 	int ret;
 
@@ -1307,6 +1308,8 @@ int mlx5_eswitch_enable(struct mlx5_eswitch *esw, int num_vfs)
 	if (toggle_lag)
 		mlx5_lag_disable_change(esw->dev);
 
+	devlink = priv_to_devlink(esw->dev);
+	devl_lock(devlink);
 	down_write(&esw->mode_lock);
 	if (!mlx5_esw_is_fdb_created(esw)) {
 		ret = mlx5_eswitch_enable_locked(esw, num_vfs);
@@ -1320,6 +1323,7 @@ int mlx5_eswitch_enable(struct mlx5_eswitch *esw, int num_vfs)
 			esw->esw_funcs.num_vfs = num_vfs;
 	}
 	up_write(&esw->mode_lock);
+	devl_unlock(devlink);
 
 	if (toggle_lag)
 		mlx5_lag_enable_change(esw->dev);
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
index f1640e4cb719..1bfbc88f513f 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
@@ -2177,8 +2177,10 @@ static int esw_create_restore_table(struct mlx5_eswitch *esw)
 static int esw_offloads_start(struct mlx5_eswitch *esw,
 			      struct netlink_ext_ack *extack)
 {
+	struct devlink *devlink = priv_to_devlink(esw->dev);
 	int err, err1;
 
+	devl_lock(devlink);
 	esw->mode = MLX5_ESWITCH_OFFLOADS;
 	err = mlx5_eswitch_enable_locked(esw, esw->dev->priv.sriov.num_vfs);
 	if (err) {
@@ -2200,6 +2202,7 @@ static int esw_offloads_start(struct mlx5_eswitch *esw,
 					   "Inline mode is different between vports");
 		}
 	}
+	devl_unlock(devlink);
 	return err;
 }
 
@@ -3064,6 +3067,7 @@ static void esw_offloads_steering_cleanup(struct mlx5_eswitch *esw)
 static void
 esw_vfs_changed_event_handler(struct mlx5_eswitch *esw, const u32 *out)
 {
+	struct devlink *devlink;
 	bool host_pf_disabled;
 	u16 new_num_vfs;
 
@@ -3075,6 +3079,8 @@ esw_vfs_changed_event_handler(struct mlx5_eswitch *esw, const u32 *out)
 	if (new_num_vfs == esw->esw_funcs.num_vfs || host_pf_disabled)
 		return;
 
+	devlink = priv_to_devlink(esw->dev);
+	devl_lock(devlink);
 	/* Number of VFs can only change from "0 to x" or "x to 0". */
 	if (esw->esw_funcs.num_vfs > 0) {
 		mlx5_eswitch_unload_vf_vports(esw, esw->esw_funcs.num_vfs);
@@ -3087,6 +3093,7 @@ esw_vfs_changed_event_handler(struct mlx5_eswitch *esw, const u32 *out)
 			return;
 	}
 	esw->esw_funcs.num_vfs = new_num_vfs;
+	devl_unlock(devlink);
 }
 
 static void esw_functions_changed_event_handler(struct work_struct *work)
@@ -3236,8 +3243,10 @@ int esw_offloads_enable(struct mlx5_eswitch *esw)
 static int esw_offloads_stop(struct mlx5_eswitch *esw,
 			     struct netlink_ext_ack *extack)
 {
+	struct devlink *devlink = priv_to_devlink(esw->dev);
 	int err, err1;
 
+	devl_lock(devlink);
 	esw->mode = MLX5_ESWITCH_LEGACY;
 	err = mlx5_eswitch_enable_locked(esw, MLX5_ESWITCH_IGNORE_NUM_VFS);
 	if (err) {
@@ -3249,6 +3258,7 @@ static int esw_offloads_stop(struct mlx5_eswitch *esw,
 					   "Failed setting eswitch back to offloads");
 		}
 	}
+	devl_unlock(devlink);
 
 	return err;
 }
-- 
2.36.1

[PATCH net-next 5/9] net/mlx5: Use devl_ API in mlx5_esw_devlink_sf_port_register

[Saeed Mahameed]

From: Moshe Shemesh <moshe@nvidia.com>

The function mlx5_esw_devlink_sf_port_register() calls
devlink_port_register() and devlink_rate_leaf_create(). Use devl_ API to
call devl_port_register() and devl_rate_leaf_create() accordingly and
add devlink instance lock in driver paths to this function.

Similarly, use devl_ API to call devl_port_unregister() and
devl_rate_leaf_destroy() in mlx5_esw_devlink_sf_port_unregister() and
ensure locking devlink instance lock on all the paths to this function
too.

This will be used by the downstream patch to invoke
mlx5_devlink_eswitch_mode_set() with devlink lock held.

Note this patch is taking devlink lock on mlx5_devlink_sf_port_new/del()
which are devlink callbacks for port_new/del(). We will take these locks
off once these callbacks will be locked by devlink too.

Signed-off-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
---
 .../net/ethernet/mellanox/mlx5/core/esw/devlink_port.c | 10 +++++-----
 drivers/net/ethernet/mellanox/mlx5/core/sf/devlink.c   |  4 ++++
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/esw/devlink_port.c b/drivers/net/ethernet/mellanox/mlx5/core/esw/devlink_port.c
index a8f7618831f5..9bc7be95db54 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/esw/devlink_port.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/esw/devlink_port.c
@@ -156,11 +156,11 @@ int mlx5_esw_devlink_sf_port_register(struct mlx5_eswitch *esw, struct devlink_p
 	devlink_port_attrs_pci_sf_set(dl_port, controller, pfnum, sfnum, !!controller);
 	devlink = priv_to_devlink(dev);
 	dl_port_index = mlx5_esw_vport_to_devlink_port_index(dev, vport_num);
-	err = devlink_port_register(devlink, dl_port, dl_port_index);
+	err = devl_port_register(devlink, dl_port, dl_port_index);
 	if (err)
 		return err;
 
-	err = devlink_rate_leaf_create(dl_port, vport);
+	err = devl_rate_leaf_create(dl_port, vport);
 	if (err)
 		goto rate_err;
 
@@ -168,7 +168,7 @@ int mlx5_esw_devlink_sf_port_register(struct mlx5_eswitch *esw, struct devlink_p
 	return 0;
 
 rate_err:
-	devlink_port_unregister(dl_port);
+	devl_port_unregister(dl_port);
 	return err;
 }
 
@@ -182,9 +182,9 @@ void mlx5_esw_devlink_sf_port_unregister(struct mlx5_eswitch *esw, u16 vport_num
 
 	if (vport->dl_port->devlink_rate) {
 		mlx5_esw_qos_vport_update_group(esw, vport, NULL, NULL);
-		devlink_rate_leaf_destroy(vport->dl_port);
+		devl_rate_leaf_destroy(vport->dl_port);
 	}
 
-	devlink_port_unregister(vport->dl_port);
+	devl_port_unregister(vport->dl_port);
 	vport->dl_port = NULL;
 }
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/sf/devlink.c b/drivers/net/ethernet/mellanox/mlx5/core/sf/devlink.c
index 7d955a4d9f14..2068c22ff367 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/sf/devlink.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/sf/devlink.c
@@ -355,7 +355,9 @@ int mlx5_devlink_sf_port_new(struct devlink *devlink,
 				   "Port add is only supported in eswitch switchdev mode or SF ports are disabled.");
 		return -EOPNOTSUPP;
 	}
+	devl_lock(devlink);
 	err = mlx5_sf_add(dev, table, new_attr, extack, new_port_index);
+	devl_unlock(devlink);
 	mlx5_sf_table_put(table);
 	return err;
 }
@@ -400,7 +402,9 @@ int mlx5_devlink_sf_port_del(struct devlink *devlink, unsigned int port_index,
 		goto sf_err;
 	}
 
+	devl_lock(devlink);
 	mlx5_esw_offloads_sf_vport_disable(esw, sf->hw_fn_id);
+	devl_unlock(devlink);
 	mlx5_sf_id_erase(table, sf);
 
 	mutex_lock(&table->sf_state_lock);
-- 
2.36.1

[PATCH net-next 6/9] devlink: Remove unused functions devlink_rate_leaf_create/destroy

[Saeed Mahameed]

From: Moshe Shemesh <moshe@nvidia.com>

The previous patch removed the last usage of the functions
devlink_rate_leaf_create() and devlink_rate_nodes_destroy(). Thus,
remove these function from devlink API.

Signed-off-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
---
 include/net/devlink.h |  2 --
 net/core/devlink.c    | 42 +++++++-----------------------------------
 2 files changed, 7 insertions(+), 37 deletions(-)

diff --git a/include/net/devlink.h b/include/net/devlink.h
index 0e163cc87d45..5150deb67fab 100644
--- a/include/net/devlink.h
+++ b/include/net/devlink.h
@@ -1569,8 +1569,6 @@ void devlink_port_attrs_pci_vf_set(struct devlink_port *devlink_port, u32 contro
 void devlink_port_attrs_pci_sf_set(struct devlink_port *devlink_port,
 				   u32 controller, u16 pf, u32 sf,
 				   bool external);
-int devlink_rate_leaf_create(struct devlink_port *port, void *priv);
-void devlink_rate_leaf_destroy(struct devlink_port *devlink_port);
 void devlink_port_linecard_set(struct devlink_port *devlink_port,
 			       struct devlink_linecard *linecard);
 struct devlink_linecard *
diff --git a/net/core/devlink.c b/net/core/devlink.c
index 1588e2246234..970e5c2a52bd 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -10006,20 +10006,13 @@ int devl_rate_leaf_create(struct devlink_port *devlink_port, void *priv)
 }
 EXPORT_SYMBOL_GPL(devl_rate_leaf_create);
 
-int
-devlink_rate_leaf_create(struct devlink_port *devlink_port, void *priv)
-{
-	struct devlink *devlink = devlink_port->devlink;
-	int ret;
-
-	mutex_lock(&devlink->lock);
-	ret = devl_rate_leaf_create(devlink_port, priv);
-	mutex_unlock(&devlink->lock);
-
-	return ret;
-}
-EXPORT_SYMBOL_GPL(devlink_rate_leaf_create);
-
+/**
+ * devl_rate_leaf_destroy - destroy devlink rate leaf
+ *
+ * @devlink_port: devlink port linked to the rate object
+ *
+ * Destroy the devlink rate object of type leaf on provided @devlink_port.
+ */
 void devl_rate_leaf_destroy(struct devlink_port *devlink_port)
 {
 	struct devlink_rate *devlink_rate = devlink_port->devlink_rate;
@@ -10037,27 +10030,6 @@ void devl_rate_leaf_destroy(struct devlink_port *devlink_port)
 }
 EXPORT_SYMBOL_GPL(devl_rate_leaf_destroy);
 
-/**
- * devlink_rate_leaf_destroy - destroy devlink rate leaf
- *
- * @devlink_port: devlink port linked to the rate object
- *
- * Context: Takes and release devlink->lock <mutex>.
- */
-void devlink_rate_leaf_destroy(struct devlink_port *devlink_port)
-{
-	struct devlink_rate *devlink_rate = devlink_port->devlink_rate;
-	struct devlink *devlink = devlink_port->devlink;
-
-	if (!devlink_rate)
-		return;
-
-	mutex_lock(&devlink->lock);
-	devl_rate_leaf_destroy(devlink_port);
-	mutex_unlock(&devlink->lock);
-}
-EXPORT_SYMBOL_GPL(devlink_rate_leaf_destroy);
-
 /**
  * devl_rate_nodes_destroy - destroy all devlink rate nodes on device
  * @devlink: devlink instance
-- 
2.36.1

[PATCH net-next 7/9] net/mlx5: Use devl_ API in mlx5e_devlink_port_register

[Saeed Mahameed]

From: Moshe Shemesh <moshe@nvidia.com>

As part of the flows invoked by mlx5_devlink_eswitch_mode_set() get to
mlx5_rescan_drivers_locked() which can call mlx5e_probe()/mlx5e_remove
and register/unregister mlx5e driver ports accordingly. This can lead to
deadlock once mlx5_devlink_eswitch_mode_set() will use devlink lock.
Use devl_port_register/unregister() instead of
devlink_port_register/unregister() and add devlink instance locks in the
driver paths to this function to have it locked while calling devl_ API
function.

If remove or probe were called by module init or module cleanup flows,
need to lock devlink just before calling devl_port_register(), otherwise
it is called by attach/detach or register/unregister flow and we can
have the flow locked. Added flag to distinguish between these cases.

This will be used by the downstream patch to invoke
mlx5_devlink_eswitch_mode_set() with devlink locked.

Signed-off-by: Moshe Shemesh <moshe@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
---
 drivers/net/ethernet/mellanox/mlx5/core/dev.c | 29 +++++++++++++++++--
 .../ethernet/mellanox/mlx5/core/en/devlink.c  | 16 ++++++++--
 .../mellanox/mlx5/core/eswitch_offloads.c     |  2 ++
 include/linux/mlx5/driver.h                   |  4 +++
 4 files changed, 47 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/dev.c b/drivers/net/ethernet/mellanox/mlx5/core/dev.c
index 50422b56a64d..ccf2068d2e79 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/dev.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/dev.c
@@ -335,13 +335,16 @@ static void del_adev(struct auxiliary_device *adev)
 
 int mlx5_attach_device(struct mlx5_core_dev *dev)
 {
+	struct devlink *devlink = priv_to_devlink(dev);
 	struct mlx5_priv *priv = &dev->priv;
 	struct auxiliary_device *adev;
 	struct auxiliary_driver *adrv;
 	int ret = 0, i;
 
+	devl_lock(devlink);
 	mutex_lock(&mlx5_intf_mutex);
 	priv->flags &= ~MLX5_PRIV_FLAGS_DETACH;
+	priv->flags |= MLX5_PRIV_FLAGS_MLX5E_LOCKED_FLOW;
 	for (i = 0; i < ARRAY_SIZE(mlx5_adev_devices); i++) {
 		if (!priv->adev[i]) {
 			bool is_supported = false;
@@ -389,19 +392,24 @@ int mlx5_attach_device(struct mlx5_core_dev *dev)
 			break;
 		}
 	}
+	priv->flags &= ~MLX5_PRIV_FLAGS_MLX5E_LOCKED_FLOW;
 	mutex_unlock(&mlx5_intf_mutex);
+	devl_unlock(devlink);
 	return ret;
 }
 
 void mlx5_detach_device(struct mlx5_core_dev *dev)
 {
+	struct devlink *devlink = priv_to_devlink(dev);
 	struct mlx5_priv *priv = &dev->priv;
 	struct auxiliary_device *adev;
 	struct auxiliary_driver *adrv;
 	pm_message_t pm = {};
 	int i;
 
+	devl_lock(devlink);
 	mutex_lock(&mlx5_intf_mutex);
+	priv->flags |= MLX5_PRIV_FLAGS_MLX5E_LOCKED_FLOW;
 	for (i = ARRAY_SIZE(mlx5_adev_devices) - 1; i >= 0; i--) {
 		if (!priv->adev[i])
 			continue;
@@ -430,18 +438,24 @@ void mlx5_detach_device(struct mlx5_core_dev *dev)
 		del_adev(&priv->adev[i]->adev);
 		priv->adev[i] = NULL;
 	}
+	priv->flags &= ~MLX5_PRIV_FLAGS_MLX5E_LOCKED_FLOW;
 	priv->flags |= MLX5_PRIV_FLAGS_DETACH;
 	mutex_unlock(&mlx5_intf_mutex);
+	devl_unlock(devlink);
 }
 
 int mlx5_register_device(struct mlx5_core_dev *dev)
 {
+	struct devlink *devlink;
 	int ret;
 
+	devlink = priv_to_devlink(dev);
+	devl_lock(devlink);
 	mutex_lock(&mlx5_intf_mutex);
 	dev->priv.flags &= ~MLX5_PRIV_FLAGS_DISABLE_ALL_ADEV;
 	ret = mlx5_rescan_drivers_locked(dev);
 	mutex_unlock(&mlx5_intf_mutex);
+	devl_unlock(devlink);
 	if (ret)
 		mlx5_unregister_device(dev);
 
@@ -450,10 +464,15 @@ int mlx5_register_device(struct mlx5_core_dev *dev)
 
 void mlx5_unregister_device(struct mlx5_core_dev *dev)
 {
+	struct devlink *devlink;
+
+	devlink = priv_to_devlink(dev);
+	devl_lock(devlink);
 	mutex_lock(&mlx5_intf_mutex);
 	dev->priv.flags = MLX5_PRIV_FLAGS_DISABLE_ALL_ADEV;
 	mlx5_rescan_drivers_locked(dev);
 	mutex_unlock(&mlx5_intf_mutex);
+	devl_unlock(devlink);
 }
 
 static int add_drivers(struct mlx5_core_dev *dev)
@@ -526,16 +545,22 @@ static void delete_drivers(struct mlx5_core_dev *dev)
 int mlx5_rescan_drivers_locked(struct mlx5_core_dev *dev)
 {
 	struct mlx5_priv *priv = &dev->priv;
+	int err = 0;
 
 	lockdep_assert_held(&mlx5_intf_mutex);
 	if (priv->flags & MLX5_PRIV_FLAGS_DETACH)
 		return 0;
 
+	priv->flags |= MLX5_PRIV_FLAGS_MLX5E_LOCKED_FLOW;
 	delete_drivers(dev);
 	if (priv->flags & MLX5_PRIV_FLAGS_DISABLE_ALL_ADEV)
-		return 0;
+		goto out;
+
+	err = add_drivers(dev);
 
-	return add_drivers(dev);
+out:
+	priv->flags &= ~MLX5_PRIV_FLAGS_MLX5E_LOCKED_FLOW;
+	return err;
 }
 
 bool mlx5_same_hw_devs(struct mlx5_core_dev *dev, struct mlx5_core_dev *peer_dev)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/devlink.c b/drivers/net/ethernet/mellanox/mlx5/core/en/devlink.c
index ae52e7f38306..b69f9d10ccbd 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/devlink.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/devlink.c
@@ -21,6 +21,7 @@ int mlx5e_devlink_port_register(struct mlx5e_priv *priv)
 	struct netdev_phys_item_id ppid = {};
 	struct devlink_port *dl_port;
 	unsigned int dl_port_index;
+	int ret;
 
 	if (mlx5_core_is_pf(priv->mdev)) {
 		attrs.flavour = DEVLINK_PORT_FLAVOUR_PHYSICAL;
@@ -41,7 +42,13 @@ int mlx5e_devlink_port_register(struct mlx5e_priv *priv)
 	memset(dl_port, 0, sizeof(*dl_port));
 	devlink_port_attrs_set(dl_port, &attrs);
 
-	return devlink_port_register(devlink, dl_port, dl_port_index);
+	if (!(priv->mdev->priv.flags & MLX5_PRIV_FLAGS_MLX5E_LOCKED_FLOW))
+		devl_lock(devlink);
+	ret = devl_port_register(devlink, dl_port, dl_port_index);
+	if (!(priv->mdev->priv.flags & MLX5_PRIV_FLAGS_MLX5E_LOCKED_FLOW))
+		devl_unlock(devlink);
+
+	return ret;
 }
 
 void mlx5e_devlink_port_type_eth_set(struct mlx5e_priv *priv)
@@ -54,8 +61,13 @@ void mlx5e_devlink_port_type_eth_set(struct mlx5e_priv *priv)
 void mlx5e_devlink_port_unregister(struct mlx5e_priv *priv)
 {
 	struct devlink_port *dl_port = mlx5e_devlink_get_dl_port(priv);
+	struct devlink *devlink = priv_to_devlink(priv->mdev);
 
-	devlink_port_unregister(dl_port);
+	if (!(priv->mdev->priv.flags & MLX5_PRIV_FLAGS_MLX5E_LOCKED_FLOW))
+		devl_lock(devlink);
+	devl_port_unregister(dl_port);
+	if (!(priv->mdev->priv.flags & MLX5_PRIV_FLAGS_MLX5E_LOCKED_FLOW))
+		devl_unlock(devlink);
 }
 
 struct devlink_port *mlx5e_get_devlink_port(struct net_device *dev)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
index 1bfbc88f513f..ccda3a0a2594 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
@@ -3400,7 +3400,9 @@ int mlx5_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode,
 		err = esw_offloads_start(esw, extack);
 	} else if (mode == DEVLINK_ESWITCH_MODE_LEGACY) {
 		err = esw_offloads_stop(esw, extack);
+		devl_lock(devlink);
 		mlx5_rescan_drivers(esw->dev);
+		devl_unlock(devlink);
 	} else {
 		err = -EINVAL;
 	}
diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h
index 76d7661e3e63..bd882884b23c 100644
--- a/include/linux/mlx5/driver.h
+++ b/include/linux/mlx5/driver.h
@@ -551,6 +551,10 @@ enum {
 	 * creation/deletion on drivers rescan. Unset during device attach.
 	 */
 	MLX5_PRIV_FLAGS_DETACH = 1 << 2,
+	/* Distinguish between mlx5e_probe/remove called by module init/cleanup
+	 * and called by other flows which can already hold devlink lock
+	 */
+	MLX5_PRIV_FLAGS_MLX5E_LOCKED_FLOW = 1 << 3,
 };
 
 struct mlx5_adev {
-- 
2.36.1

[PATCH net-next 8/9] net/mlx5: Remove devl_unlock from mlx5_devlink_eswitch_mode_set

[Saeed Mahameed]

From: Moshe Shemesh <moshe@nvidia.com>

The callback mlx5_devlink_eswitch_mode_set() had unlocked devlink as a
temporary workaround once devlink instance lock was added to devlink
eswitch callbacks. Now that all flows triggered by this function
that took devlink lock are using devl_ API and all parallel paths are
locked we can remove this workaround.

Signed-off-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
---
 .../mellanox/mlx5/core/eswitch_offloads.c     | 20 -------------------
 1 file changed, 20 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
index ccda3a0a2594..d3da52e3fc67 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
@@ -2177,10 +2177,8 @@ static int esw_create_restore_table(struct mlx5_eswitch *esw)
 static int esw_offloads_start(struct mlx5_eswitch *esw,
 			      struct netlink_ext_ack *extack)
 {
-	struct devlink *devlink = priv_to_devlink(esw->dev);
 	int err, err1;
 
-	devl_lock(devlink);
 	esw->mode = MLX5_ESWITCH_OFFLOADS;
 	err = mlx5_eswitch_enable_locked(esw, esw->dev->priv.sriov.num_vfs);
 	if (err) {
@@ -2202,7 +2200,6 @@ static int esw_offloads_start(struct mlx5_eswitch *esw,
 					   "Inline mode is different between vports");
 		}
 	}
-	devl_unlock(devlink);
 	return err;
 }
 
@@ -3243,10 +3240,8 @@ int esw_offloads_enable(struct mlx5_eswitch *esw)
 static int esw_offloads_stop(struct mlx5_eswitch *esw,
 			     struct netlink_ext_ack *extack)
 {
-	struct devlink *devlink = priv_to_devlink(esw->dev);
 	int err, err1;
 
-	devl_lock(devlink);
 	esw->mode = MLX5_ESWITCH_LEGACY;
 	err = mlx5_eswitch_enable_locked(esw, MLX5_ESWITCH_IGNORE_NUM_VFS);
 	if (err) {
@@ -3258,7 +3253,6 @@ static int esw_offloads_stop(struct mlx5_eswitch *esw,
 					   "Failed setting eswitch back to offloads");
 		}
 	}
-	devl_unlock(devlink);
 
 	return err;
 }
@@ -3366,15 +3360,6 @@ int mlx5_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode,
 	if (esw_mode_from_devlink(mode, &mlx5_mode))
 		return -EINVAL;
 
-	/* FIXME: devl_unlock() followed by devl_lock() inside driver callback
-	 * is never correct and prone to races. It's a transitional workaround,
-	 * never repeat this pattern.
-	 *
-	 * This code MUST be fixed before removing devlink_mutex as it is safe
-	 * to do only because of that mutex.
-	 */
-	devl_unlock(devlink);
-
 	mlx5_lag_disable_change(esw->dev);
 	err = mlx5_esw_try_lock(esw);
 	if (err < 0) {
@@ -3387,9 +3372,7 @@ int mlx5_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode,
 	if (cur_mlx5_mode == mlx5_mode)
 		goto unlock;
 
-	devl_lock(devlink);
 	mlx5_eswitch_disable_locked(esw);
-	devl_unlock(devlink);
 	if (mode == DEVLINK_ESWITCH_MODE_SWITCHDEV) {
 		if (mlx5_devlink_trap_get_num_active(esw->dev)) {
 			NL_SET_ERR_MSG_MOD(extack,
@@ -3400,9 +3383,7 @@ int mlx5_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode,
 		err = esw_offloads_start(esw, extack);
 	} else if (mode == DEVLINK_ESWITCH_MODE_LEGACY) {
 		err = esw_offloads_stop(esw, extack);
-		devl_lock(devlink);
 		mlx5_rescan_drivers(esw->dev);
-		devl_unlock(devlink);
 	} else {
 		err = -EINVAL;
 	}
@@ -3411,7 +3392,6 @@ int mlx5_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode,
 	mlx5_esw_unlock(esw);
 enable_lag:
 	mlx5_lag_enable_change(esw->dev);
-	devl_lock(devlink);
 	return err;
 }
 
-- 
2.36.1

[PATCH net-next 9/9] devlink: Hold the instance lock in port_new / port_del callbacks

[Saeed Mahameed]

From: Moshe Shemesh <moshe@nvidia.com>

Let the core take the devlink instance lock around port_new and port_del
callbacks and remove the now redundant locking in the only driver that
currently use them.

Signed-off-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
---
 drivers/net/ethernet/mellanox/mlx5/core/sf/devlink.c | 4 ----
 net/core/devlink.c                                   | 6 +-----
 2 files changed, 1 insertion(+), 9 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/sf/devlink.c b/drivers/net/ethernet/mellanox/mlx5/core/sf/devlink.c
index 2068c22ff367..7d955a4d9f14 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/sf/devlink.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/sf/devlink.c
@@ -355,9 +355,7 @@ int mlx5_devlink_sf_port_new(struct devlink *devlink,
 				   "Port add is only supported in eswitch switchdev mode or SF ports are disabled.");
 		return -EOPNOTSUPP;
 	}
-	devl_lock(devlink);
 	err = mlx5_sf_add(dev, table, new_attr, extack, new_port_index);
-	devl_unlock(devlink);
 	mlx5_sf_table_put(table);
 	return err;
 }
@@ -402,9 +400,7 @@ int mlx5_devlink_sf_port_del(struct devlink *devlink, unsigned int port_index,
 		goto sf_err;
 	}
 
-	devl_lock(devlink);
 	mlx5_esw_offloads_sf_vport_disable(esw, sf->hw_fn_id);
-	devl_unlock(devlink);
 	mlx5_sf_id_erase(table, sf);
 
 	mutex_lock(&table->sf_state_lock);
diff --git a/net/core/devlink.c b/net/core/devlink.c
index 970e5c2a52bd..e206cc90bec5 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -1712,7 +1712,7 @@ static int devlink_port_new_notifiy(struct devlink *devlink,
 	if (!msg)
 		return -ENOMEM;
 
-	mutex_lock(&devlink->lock);
+	lockdep_assert_held(&devlink->lock);
 	devlink_port = devlink_port_get_by_index(devlink, port_index);
 	if (!devlink_port) {
 		err = -ENODEV;
@@ -1725,11 +1725,9 @@ static int devlink_port_new_notifiy(struct devlink *devlink,
 		goto out;
 
 	err = genlmsg_reply(msg, info);
-	mutex_unlock(&devlink->lock);
 	return err;
 
 out:
-	mutex_unlock(&devlink->lock);
 	nlmsg_free(msg);
 	return err;
 }
@@ -9067,13 +9065,11 @@ static const struct genl_small_ops devlink_nl_ops[] = {
 		.cmd = DEVLINK_CMD_PORT_NEW,
 		.doit = devlink_nl_cmd_port_new_doit,
 		.flags = GENL_ADMIN_PERM,
-		.internal_flags = DEVLINK_NL_FLAG_NO_LOCK,
 	},
 	{
 		.cmd = DEVLINK_CMD_PORT_DEL,
 		.doit = devlink_nl_cmd_port_del_doit,
 		.flags = GENL_ADMIN_PERM,
-		.internal_flags = DEVLINK_NL_FLAG_NO_LOCK,
 	},
 	{
 		.cmd = DEVLINK_CMD_LINECARD_GET,
-- 
2.36.1

Re: [PATCH net-next 0/9] mlx5 devlink mutex removal part 1

[Jakub Kicinski]

On Mon, 11 Jul 2022 01:13:59 -0700 Saeed Mahameed wrote:
> 1) Fix devlink lock in mlx5 devlink eswitch callbacks
> 
> Following the commit 14e426bf1a4d "devlink: hold the instance lock
> during eswitch_mode callbacks" which takes devlink instance lock for all
> devlink eswitch callbacks and adds a temporary workaround, this patchset
> removes the workaround, replaces devlink API functions by devl_ API
> where called from mlx5 driver eswitch callbacks flows and adds devlink
> instance lock in other driver's path that leads to these functions.
> While moving to devl_ API the patchset removes part of the devlink API
> functions which mlx5 was the last one to use and so not used by any
> driver now.
> 
> The patchset also remove DEVLINK_NL_FLAG_NO_LOCK flag from the callbacks
> of port_new/port which are called only from mlx5 driver and the already
> locked by the patchset as parallel paths to the eswitch callbacks using
> devl_ API functions.
> 
> This patchset will be followed by another patchset that will remove
> DEVLINK_NL_FLAG_NO_LOCK flag from devlink reload and devlink health
> callbacks. Thus we will have all devlink callbacks locked and it will
> pave the way to remove devlink mutex.

Acked-by: Jakub Kicinski <kuba@kernel.org>

Re: [PATCH net-next 0/9] mlx5 devlink mutex removal part 1

[patchwork-bot+netdevbpf]

Hello:

This series was applied to netdev/net-next.git (master)
by Paolo Abeni <pabeni@redhat.com>:

On Mon, 11 Jul 2022 01:13:59 -0700 you wrote:
> From: Saeed Mahameed <saeedm@nvidia.com>
> 
> Moshe Shemesh Says:
> ===================
> 1) Fix devlink lock in mlx5 devlink eswitch callbacks
> 
> Following the commit 14e426bf1a4d "devlink: hold the instance lock
> during eswitch_mode callbacks" which takes devlink instance lock for all
> devlink eswitch callbacks and adds a temporary workaround, this patchset
> removes the workaround, replaces devlink API functions by devl_ API
> where called from mlx5 driver eswitch callbacks flows and adds devlink
> instance lock in other driver's path that leads to these functions.
> While moving to devl_ API the patchset removes part of the devlink API
> functions which mlx5 was the last one to use and so not used by any
> driver now.
> 
> [...]

Here is the summary with links:
  - [net-next,1/9] net/mlx5: Remove devl_unlock from mlx5_eswtich_mode_callback_enter
    https://git.kernel.org/netdev/net-next/c/367dfa121205
  - [net-next,2/9] net/mlx5: Use devl_ API for rate nodes destroy
    https://git.kernel.org/netdev/net-next/c/03f9c47d0f79
  - [net-next,3/9] devlink: Remove unused function devlink_rate_nodes_destroy
    https://git.kernel.org/netdev/net-next/c/868232f5cd38
  - [net-next,4/9] net/mlx5: Use devl_ API in mlx5_esw_offloads_devlink_port_register
    https://git.kernel.org/netdev/net-next/c/f1bc646c9a06
  - [net-next,5/9] net/mlx5: Use devl_ API in mlx5_esw_devlink_sf_port_register
    https://git.kernel.org/netdev/net-next/c/da212bd29d7f
  - [net-next,6/9] devlink: Remove unused functions devlink_rate_leaf_create/destroy
    https://git.kernel.org/netdev/net-next/c/df539fc62b06
  - [net-next,7/9] net/mlx5: Use devl_ API in mlx5e_devlink_port_register
    https://git.kernel.org/netdev/net-next/c/7b19119f4c7d
  - [net-next,8/9] net/mlx5: Remove devl_unlock from mlx5_devlink_eswitch_mode_set
    https://git.kernel.org/netdev/net-next/c/973598d46ede
  - [net-next,9/9] devlink: Hold the instance lock in port_new / port_del callbacks
    https://git.kernel.org/netdev/net-next/c/f0680ef0f949

You are awesome, thank you!
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