summaryrefslogtreecommitdiffstats
path: root/Documentation/networking
diff options
context:
space:
mode:
authorFlorian Westphal <fw@strlen.de>2016-04-24 21:38:14 +0200
committerDavid S. Miller <davem@davemloft.net>2016-04-26 15:53:05 -0400
commitf0cdf76c103ffa34ca5ac87dcdef7edffc722cbf (patch)
tree893afe6a3b448bfeb0dd36cae35a6ce844230852 /Documentation/networking
parenta6086a893718db07ef9e7af5624ec27cb376ef0a (diff)
downloadop-kernel-dev-f0cdf76c103ffa34ca5ac87dcdef7edffc722cbf.zip
op-kernel-dev-f0cdf76c103ffa34ca5ac87dcdef7edffc722cbf.tar.gz
net: remove NETDEV_TX_LOCKED support
No more users in the tree, remove NETDEV_TX_LOCKED support. Adds another hole in softnet_stats struct, but better than keeping the unused collision counter around. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'Documentation/networking')
-rw-r--r--Documentation/networking/netdev-features.txt10
-rw-r--r--Documentation/networking/netdevices.txt9
2 files changed, 7 insertions, 12 deletions
diff --git a/Documentation/networking/netdev-features.txt b/Documentation/networking/netdev-features.txt
index f310ede..7413eb0 100644
--- a/Documentation/networking/netdev-features.txt
+++ b/Documentation/networking/netdev-features.txt
@@ -131,13 +131,11 @@ stack. Driver should not change behaviour based on them.
* LLTX driver (deprecated for hardware drivers)
-NETIF_F_LLTX should be set in drivers that implement their own locking in
-transmit path or don't need locking at all (e.g. software tunnels).
-In ndo_start_xmit, it is recommended to use a try_lock and return
-NETDEV_TX_LOCKED when the spin lock fails. The locking should also properly
-protect against other callbacks (the rules you need to find out).
+NETIF_F_LLTX is meant to be used by drivers that don't need locking at all,
+e.g. software tunnels.
-Don't use it for new drivers.
+This is also used in a few legacy drivers that implement their
+own locking, don't use it for new (hardware) drivers.
* netns-local device
diff --git a/Documentation/networking/netdevices.txt b/Documentation/networking/netdevices.txt
index 0b1cf6b..7fec206 100644
--- a/Documentation/networking/netdevices.txt
+++ b/Documentation/networking/netdevices.txt
@@ -69,10 +69,9 @@ ndo_start_xmit:
When the driver sets NETIF_F_LLTX in dev->features this will be
called without holding netif_tx_lock. In this case the driver
- has to lock by itself when needed. It is recommended to use a try lock
- for this and return NETDEV_TX_LOCKED when the spin lock fails.
- The locking there should also properly protect against
- set_rx_mode. Note that the use of NETIF_F_LLTX is deprecated.
+ has to lock by itself when needed.
+ The locking there should also properly protect against
+ set_rx_mode. WARNING: use of NETIF_F_LLTX is deprecated.
Don't use it for new drivers.
Context: Process with BHs disabled or BH (timer),
@@ -83,8 +82,6 @@ ndo_start_xmit:
o NETDEV_TX_BUSY Cannot transmit packet, try later
Usually a bug, means queue start/stop flow control is broken in
the driver. Note: the driver must NOT put the skb in its DMA ring.
- o NETDEV_TX_LOCKED Locking failed, please retry quickly.
- Only valid when NETIF_F_LLTX is set.
ndo_tx_timeout:
Synchronization: netif_tx_lock spinlock; all TX queues frozen.
OpenPOWER on IntegriCloud