summaryrefslogtreecommitdiffstats
path: root/net/dsa/dsa.c
diff options
context:
space:
mode:
authorVladimir Oltean <vladimir.oltean@nxp.com>2020-05-05 22:20:52 +0300
committerDavid S. Miller <davem@davemloft.net>2020-05-07 17:31:57 -0700
commite1eea8112017cbdc596d90caf6ede191502a9691 (patch)
tree7c6b7b13a40c2e4587fc629b4204a7c8a8efaa96 /net/dsa/dsa.c
parentbb206a0869b7f1e7c853d7b94e91510c321402c7 (diff)
downloadlinux-e1eea8112017cbdc596d90caf6ede191502a9691.tar.bz2
net: dsa: introduce a dsa_port_from_netdev public helper
As its implementation shows, this is synonimous with calling dsa_slave_dev_check followed by dsa_slave_to_port, so it is quite simple already and provides functionality which is already there. However there is now a need for these functions outside dsa_priv.h, for example in drivers that perform mirroring and redirection through tc-flower offloads (they are given raw access to the flow_cls_offload structure), where they need to call this function on act->dev. But simply exporting dsa_slave_to_port would make it non-inline and would result in an extra function call in the hotpath, as can be seen for example in sja1105: Before: 000006dc <sja1105_xmit>: { 6dc: e92d4ff0 push {r4, r5, r6, r7, r8, r9, sl, fp, lr} 6e0: e1a04000 mov r4, r0 6e4: e591958c ldr r9, [r1, #1420] ; 0x58c <- Inline dsa_slave_to_port 6e8: e1a05001 mov r5, r1 6ec: e24dd004 sub sp, sp, #4 u16 tx_vid = dsa_8021q_tx_vid(dp->ds, dp->index); 6f0: e1c901d8 ldrd r0, [r9, #24] 6f4: ebfffffe bl 0 <dsa_8021q_tx_vid> 6f4: R_ARM_CALL dsa_8021q_tx_vid u8 pcp = netdev_txq_to_tc(netdev, queue_mapping); 6f8: e1d416b0 ldrh r1, [r4, #96] ; 0x60 u16 tx_vid = dsa_8021q_tx_vid(dp->ds, dp->index); 6fc: e1a08000 mov r8, r0 After: 000006e4 <sja1105_xmit>: { 6e4: e92d4ff0 push {r4, r5, r6, r7, r8, r9, sl, fp, lr} 6e8: e1a04000 mov r4, r0 6ec: e24dd004 sub sp, sp, #4 struct dsa_port *dp = dsa_slave_to_port(netdev); 6f0: e1a00001 mov r0, r1 { 6f4: e1a05001 mov r5, r1 struct dsa_port *dp = dsa_slave_to_port(netdev); 6f8: ebfffffe bl 0 <dsa_slave_to_port> 6f8: R_ARM_CALL dsa_slave_to_port 6fc: e1a09000 mov r9, r0 u16 tx_vid = dsa_8021q_tx_vid(dp->ds, dp->index); 700: e1c001d8 ldrd r0, [r0, #24] 704: ebfffffe bl 0 <dsa_8021q_tx_vid> 704: R_ARM_CALL dsa_8021q_tx_vid Because we want to avoid possible performance regressions, introduce this new function which is designed to be public. Suggested-by: Vivien Didelot <vivien.didelot@gmail.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/dsa/dsa.c')
-rw-r--r--net/dsa/dsa.c9
1 files changed, 9 insertions, 0 deletions
diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index 0384a911779e..1ce9ba8cf545 100644
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c
@@ -412,6 +412,15 @@ void dsa_devlink_resource_occ_get_unregister(struct dsa_switch *ds,
}
EXPORT_SYMBOL_GPL(dsa_devlink_resource_occ_get_unregister);
+struct dsa_port *dsa_port_from_netdev(struct net_device *netdev)
+{
+ if (!netdev || !dsa_slave_dev_check(netdev))
+ return ERR_PTR(-ENODEV);
+
+ return dsa_slave_to_port(netdev);
+}
+EXPORT_SYMBOL_GPL(dsa_port_from_netdev);
+
static int __init dsa_init_module(void)
{
int rc;