[PATCH net-next 2/2] net: phy: phy_link_topology: Lazy-initialize the link topology
Maxime Chevallier
maxime.chevallier at bootlin.com
Tue May 7 03:28:21 PDT 2024
Having the net_device's init path for the link_topology depend on
IS_REACHABLE(PHYLIB)-protected helpers triggers errors when modules are being
built with phylib as a module as-well, as they expect netdev->link_topo
to be initialized.
Move the link_topo initialization at the first PHY insertion, which will
both improve the memory usage, and make the behaviour more predicatble
and robust.
Signed-off-by: Maxime Chevallier <maxime.chevallier at bootlin.com>
Fixes: 6916e461e793 ("net: phy: Introduce ethernet link topology representation")
Closes: https://lore.kernel.org/netdev/2e11b89d-100f-49e7-9c9a-834cc0b82f97@gmail.com/
Closes: https://lore.kernel.org/netdev/20240409201553.GA4124869@dev-arch.thelio-3990X/
---
drivers/net/phy/phy_link_topology.c | 31 ++++++---------------
include/linux/netdevice.h | 2 ++
include/linux/phy_link_topology.h | 23 ++++++++--------
include/linux/phy_link_topology_core.h | 23 +++-------------
net/core/dev.c | 38 ++++++++++++++++++++++----
5 files changed, 58 insertions(+), 59 deletions(-)
diff --git a/drivers/net/phy/phy_link_topology.c b/drivers/net/phy/phy_link_topology.c
index 0e36bd7c15dc..b1aba9313e73 100644
--- a/drivers/net/phy/phy_link_topology.c
+++ b/drivers/net/phy/phy_link_topology.c
@@ -12,29 +12,6 @@
#include <linux/rtnetlink.h>
#include <linux/xarray.h>
-struct phy_link_topology *phy_link_topo_create(struct net_device *dev)
-{
- struct phy_link_topology *topo;
-
- topo = kzalloc(sizeof(*topo), GFP_KERNEL);
- if (!topo)
- return ERR_PTR(-ENOMEM);
-
- xa_init_flags(&topo->phys, XA_FLAGS_ALLOC1);
- topo->next_phy_index = 1;
-
- return topo;
-}
-
-void phy_link_topo_destroy(struct phy_link_topology *topo)
-{
- if (!topo)
- return;
-
- xa_destroy(&topo->phys);
- kfree(topo);
-}
-
int phy_link_topo_add_phy(struct net_device *dev,
struct phy_device *phy,
enum phy_upstream upt, void *upstream)
@@ -43,6 +20,14 @@ int phy_link_topo_add_phy(struct net_device *dev,
struct phy_device_node *pdn;
int ret;
+ if (!topo) {
+ ret = netdev_alloc_phy_link_topology(dev);
+ if (ret)
+ return ret;
+
+ topo = dev->link_topo;
+ }
+
pdn = kzalloc(sizeof(*pdn), GFP_KERNEL);
if (!pdn)
return -ENOMEM;
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index cf261fb89d73..25a0a77cfadc 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -4569,6 +4569,8 @@ void __hw_addr_unsync_dev(struct netdev_hw_addr_list *list,
const unsigned char *));
void __hw_addr_init(struct netdev_hw_addr_list *list);
+int netdev_alloc_phy_link_topology(struct net_device *dev);
+
/* Functions used for device addresses handling */
void dev_addr_mod(struct net_device *dev, unsigned int offset,
const void *addr, size_t len);
diff --git a/include/linux/phy_link_topology.h b/include/linux/phy_link_topology.h
index 166a01710aa2..3501f9a9e932 100644
--- a/include/linux/phy_link_topology.h
+++ b/include/linux/phy_link_topology.h
@@ -32,10 +32,12 @@ struct phy_device_node {
struct phy_device *phy;
};
-struct phy_link_topology {
- struct xarray phys;
- u32 next_phy_index;
-};
+#if IS_ENABLED(CONFIG_PHYLIB)
+int phy_link_topo_add_phy(struct net_device *dev,
+ struct phy_device *phy,
+ enum phy_upstream upt, void *upstream);
+
+void phy_link_topo_del_phy(struct net_device *dev, struct phy_device *phy);
static inline struct phy_device
*phy_link_topo_get_phy(struct net_device *dev, u32 phyindex)
@@ -53,13 +55,6 @@ static inline struct phy_device
return NULL;
}
-#if IS_REACHABLE(CONFIG_PHYLIB)
-int phy_link_topo_add_phy(struct net_device *dev,
- struct phy_device *phy,
- enum phy_upstream upt, void *upstream);
-
-void phy_link_topo_del_phy(struct net_device *dev, struct phy_device *phy);
-
#else
static inline int phy_link_topo_add_phy(struct net_device *dev,
struct phy_device *phy,
@@ -72,6 +67,12 @@ static inline void phy_link_topo_del_phy(struct net_device *dev,
struct phy_device *phy)
{
}
+
+static inline struct phy_device *
+phy_link_topo_get_phy(struct net_device *dev, u32 phyindex)
+{
+ return NULL;
+}
#endif
#endif /* __PHY_LINK_TOPOLOGY_H */
diff --git a/include/linux/phy_link_topology_core.h b/include/linux/phy_link_topology_core.h
index 0a6479055745..f9c0520806fb 100644
--- a/include/linux/phy_link_topology_core.h
+++ b/include/linux/phy_link_topology_core.h
@@ -2,24 +2,9 @@
#ifndef __PHY_LINK_TOPOLOGY_CORE_H
#define __PHY_LINK_TOPOLOGY_CORE_H
-struct phy_link_topology;
-
-#if IS_REACHABLE(CONFIG_PHYLIB)
-
-struct phy_link_topology *phy_link_topo_create(struct net_device *dev);
-void phy_link_topo_destroy(struct phy_link_topology *topo);
-
-#else
-
-static inline struct phy_link_topology *phy_link_topo_create(struct net_device *dev)
-{
- return NULL;
-}
-
-static inline void phy_link_topo_destroy(struct phy_link_topology *topo)
-{
-}
-
-#endif
+struct phy_link_topology {
+ struct xarray phys;
+ u32 next_phy_index;
+};
#endif /* __PHY_LINK_TOPOLOGY_CORE_H */
diff --git a/net/core/dev.c b/net/core/dev.c
index d2ce91a334c1..1b4ffc273a04 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -10256,6 +10256,35 @@ static void netdev_do_free_pcpu_stats(struct net_device *dev)
}
}
+int netdev_alloc_phy_link_topology(struct net_device *dev)
+{
+ struct phy_link_topology *topo;
+
+ topo = kzalloc(sizeof(*topo), GFP_KERNEL);
+ if (!topo)
+ return -ENOMEM;
+
+ xa_init_flags(&topo->phys, XA_FLAGS_ALLOC1);
+ topo->next_phy_index = 1;
+
+ dev->link_topo = topo;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(netdev_alloc_phy_link_topology);
+
+static void netdev_free_phy_link_topology(struct net_device *dev)
+{
+ struct phy_link_topology *topo = dev->link_topo;
+
+ if (!topo)
+ return;
+
+ xa_destroy(&topo->phys);
+ kfree(topo);
+ dev->link_topo = NULL;
+}
+
/**
* register_netdevice() - register a network device
* @dev: device to register
@@ -10998,11 +11027,6 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
#ifdef CONFIG_NET_SCHED
hash_init(dev->qdisc_hash);
#endif
- dev->link_topo = phy_link_topo_create(dev);
- if (IS_ERR(dev->link_topo)) {
- dev->link_topo = NULL;
- goto free_all;
- }
dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM;
setup(dev);
@@ -11092,7 +11116,9 @@ void free_netdev(struct net_device *dev)
free_percpu(dev->xdp_bulkq);
dev->xdp_bulkq = NULL;
- phy_link_topo_destroy(dev->link_topo);
+#if IS_ENABLED(CONFIG_PHYLIB)
+ netdev_free_phy_link_topology(dev);
+#endif
/* Compatibility with error handling in drivers */
if (dev->reg_state == NETREG_UNINITIALIZED ||
--
2.44.0
More information about the linux-arm-kernel
mailing list