diff options
| author | Eric Dumazet <edumazet@google.com> | 2024-02-13 09:32:39 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2024-02-14 14:20:13 +0300 |
| commit | 004d138364fd10dd5ff8ceb54cfdc2d792a7b338 (patch) | |
| tree | 19491864f7a5306175afb03f896047725ffe281f /net/core | |
| parent | c7d52737e7ebd31cc5fef46380d94b58becf9479 (diff) | |
| download | linux-004d138364fd10dd5ff8ceb54cfdc2d792a7b338.tar.xz | |
net-sysfs: convert dev->operstate reads to lockless ones
operstate_show() can omit dev_base_lock acquisition only
to read dev->operstate.
Annotate accesses to dev->operstate.
Writers still acquire dev_base_lock for mutual exclusion.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core')
| -rw-r--r-- | net/core/link_watch.c | 4 | ||||
| -rw-r--r-- | net/core/net-sysfs.c | 4 | ||||
| -rw-r--r-- | net/core/rtnetlink.c | 4 |
3 files changed, 5 insertions, 7 deletions
diff --git a/net/core/link_watch.c b/net/core/link_watch.c index 429571c258da..1b93e054c9a3 100644 --- a/net/core/link_watch.c +++ b/net/core/link_watch.c @@ -67,7 +67,7 @@ static void rfc2863_policy(struct net_device *dev) { unsigned char operstate = default_operstate(dev); - if (operstate == dev->operstate) + if (operstate == READ_ONCE(dev->operstate)) return; write_lock(&dev_base_lock); @@ -87,7 +87,7 @@ static void rfc2863_policy(struct net_device *dev) break; } - dev->operstate = operstate; + WRITE_ONCE(dev->operstate, operstate); write_unlock(&dev_base_lock); } diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c index 23ef2df549c3..c5d164b8c6bf 100644 --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -325,11 +325,9 @@ static ssize_t operstate_show(struct device *dev, const struct net_device *netdev = to_net_dev(dev); unsigned char operstate; - read_lock(&dev_base_lock); - operstate = netdev->operstate; + operstate = READ_ONCE(netdev->operstate); if (!netif_running(netdev)) operstate = IF_OPER_DOWN; - read_unlock(&dev_base_lock); if (operstate >= ARRAY_SIZE(operstates)) return -EINVAL; /* should not happen */ diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index fd47a4422a51..43d92de8601c 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -866,9 +866,9 @@ static void set_operstate(struct net_device *dev, unsigned char transition) break; } - if (dev->operstate != operstate) { + if (READ_ONCE(dev->operstate) != operstate) { write_lock(&dev_base_lock); - dev->operstate = operstate; + WRITE_ONCE(dev->operstate, operstate); write_unlock(&dev_base_lock); netdev_state_change(dev); } |