diff options
| author | Eric Dumazet <edumazet@google.com> | 2024-02-13 06:32:37 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2024-02-14 11:20:13 +0000 |
| commit | 12692e3df2dacf2993c56aa23b6d3de921a5bdff (patch) | |
| tree | 9aa77ece5c3f3b08de7b19b4103cdafd9bf9fe8b /net/core/net-sysfs.c | |
| parent | 4d42b37def70327b2bb19f823d42289aed2cd7c7 (diff) | |
net-sysfs: convert netdev_show() to RCU
Make clear dev_isalive() can be called with RCU protection.
Then convert netdev_show() to RCU, to remove dev_base_lock
dependency.
Also add RCU to broadcast_show().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core/net-sysfs.c')
| -rw-r--r-- | net/core/net-sysfs.c | 17 |
1 files changed, 10 insertions, 7 deletions
diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c index f4c2b8267495..678e4be69082 100644 --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -34,10 +34,10 @@ static const char fmt_dec[] = "%d\n"; static const char fmt_ulong[] = "%lu\n"; static const char fmt_u64[] = "%llu\n"; -/* Caller holds RTNL or dev_base_lock */ +/* Caller holds RTNL, RCU or dev_base_lock */ static inline int dev_isalive(const struct net_device *dev) { - return dev->reg_state <= NETREG_REGISTERED; + return READ_ONCE(dev->reg_state) <= NETREG_REGISTERED; } /* use same locking rules as GIF* ioctl's */ @@ -48,10 +48,10 @@ static ssize_t netdev_show(const struct device *dev, struct net_device *ndev = to_net_dev(dev); ssize_t ret = -EINVAL; - read_lock(&dev_base_lock); + rcu_read_lock(); if (dev_isalive(ndev)) ret = (*format)(ndev, buf); - read_unlock(&dev_base_lock); + rcu_read_unlock(); return ret; } @@ -60,7 +60,7 @@ static ssize_t netdev_show(const struct device *dev, #define NETDEVICE_SHOW(field, format_string) \ static ssize_t format_##field(const struct net_device *dev, char *buf) \ { \ - return sysfs_emit(buf, format_string, dev->field); \ + return sysfs_emit(buf, format_string, READ_ONCE(dev->field)); \ } \ static ssize_t field##_show(struct device *dev, \ struct device_attribute *attr, char *buf) \ @@ -161,10 +161,13 @@ static ssize_t broadcast_show(struct device *dev, struct device_attribute *attr, char *buf) { struct net_device *ndev = to_net_dev(dev); + int ret = -EINVAL; + rcu_read_lock(); if (dev_isalive(ndev)) - return sysfs_format_mac(buf, ndev->broadcast, ndev->addr_len); - return -EINVAL; + ret = sysfs_format_mac(buf, ndev->broadcast, ndev->addr_len); + rcu_read_unlock(); + return ret; } static DEVICE_ATTR_RO(broadcast); |