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| author |   Zhu Yi <yi.zhu5@cn.bosch.com> | 2018-06-13 16:37:17 +0200 |
|---|---|---|
| committer |   Marc Kleine-Budde <mkl@pengutronix.de> | 2018-07-27 10:40:16 +0200 |
| commit | 038709071328ff68a936c6b8c33a24a805eea3c5 (patch) | |
| tree | 2ce62a90ee995c7355f6a6e045d90507fac089d5 /include/linux/can | |
| parent | can: dev: use skb_put_zero to simplfy code (diff) | |
| download | linux-dev-038709071328ff68a936c6b8c33a24a805eea3c5.tar.xz linux-dev-038709071328ff68a936c6b8c33a24a805eea3c5.zip | |
can: dev: enable multi-queue for SocketCAN devices
The existing SocketCAN implementation provides alloc_candev() to
allocate a CAN device using a single Tx and Rx queue. This can lead to
priority inversion in case the single Tx queue is already full with low
priority messages and a high priority message needs to be sent while the
bus is fully loaded with medium priority messages.
This problem can be solved by using the existing multi-queue support of
the network subsytem. The commit makes it possible to use multi-queue in
the CAN subsystem in the same way it is used in the Ethernet subsystem
by adding an alloc_candev_mqs() call and accompanying macros. With this
support a CAN device can use multi-queue qdisc (e.g. mqprio) to avoid
the aforementioned priority inversion.
The exisiting functionality of alloc_candev() is the same as before.
CAN devices need to have prioritized multiple hardware queues or are
able to abort waiting for arbitration to make sensible use of
multi-queues.
Signed-off-by: Zhu Yi <yi.zhu5@cn.bosch.com>
Signed-off-by: Mark Jonas <mark.jonas@de.bosch.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Diffstat (limited to 'include/linux/can')
| -rw-r--r-- | include/linux/can/dev.h | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h index 055aaf5ed9af..a83e1f632eb7 100644 --- a/include/linux/can/dev.h +++ b/include/linux/can/dev.h @@ -143,7 +143,12 @@ u8 can_dlc2len(u8 can_dlc); /* map the sanitized data length to an appropriate data length code */ u8 can_len2dlc(u8 len); -struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max); +struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max, + unsigned int txqs, unsigned int rxqs); +#define alloc_candev(sizeof_priv, echo_skb_max) \ + alloc_candev_mqs(sizeof_priv, echo_skb_max, 1, 1) +#define alloc_candev_mq(sizeof_priv, echo_skb_max, count) \ + alloc_candev_mqs(sizeof_priv, echo_skb_max, count, count) void free_candev(struct net_device *dev); /* a candev safe wrapper around netdev_priv */ |