It's common sense that when we should do change to driver ring
desc/buffer etc only after 'stop/shutdown' the device. When we
do change while devices/driver is running, kernel oops occur:
[
r...@fsl_8569mds:/root> ethtool -G eth0 tx 256
r...@fsl_8569mds:/root> Oops: Kernel access of bad area, sig: 11 [#1]
MPC8569 MDS
last sysfs file: /sys/kernel/uevent_seqnum
Modules linked in:
NIP: 00000000 LR: c0072fbc CTR: 00000000
REGS: effefef0 TRAP: 0400 Not tainted (2.6.36-rc3-00002-g6c3b118-dirty)
MSR: 00021000 <ME,CE> CR: 24442048 XER: 00000000
TASK = c0518350[0] 'swapper' THREAD: c0544000
GPR00: 00000000 effeffa0 c0518350 00000020 ef0be000 ef005000 80000000 00000200
GPR08: c03b5d00 00000000 f1010080 ef08d458 000dda96 00000000 3ffb2900 00000000
GPR16: 00000000 3ffa8948 3fff1314 3ffac3f8 00000000 00000000 00000000 00000000
GPR24: 00000000 00000000 00000000 c0530000 00000000 00000000 00000020 ef3709c0
NIP [00000000] (null)
LR [c0072fbc] handle_IRQ_event+0x4c/0x12c
Call Trace:
[effeffa0] [c0019414] qe_ic_mask_irq+0x1c/0x90 (unreliable)
[effeffc0] [c0075b74] handle_level_irq+0x88/0x128
[effeffd0] [c001ca44] qe_ic_cascade_muxed_mpic+0x50/0x88
[effefff0] [c000d5fc] call_handle_irq+0x18/0x28
[c0545ea0] [c0004f3c] do_IRQ+0xa8/0x140
[c0545ed0] [c000e2bc] ret_from_except+0x0/0x18
-- Exception: 501 at cpu_idle+0x9c/0xdc
LR = cpu_idle+0x9c/0xdc
[c0545f90] [c0008318] cpu_idle+0x54/0xdc (unreliable)
[c0545fb0] [c000231c] rest_init+0x68/0x7c
[c0545fc0] [c04e686c] start_kernel+0x230/0x2b0
[c0545ff0] [c000039c] skpinv+0x2b4/0x2f0
Instruction dump:
XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
Kernel panic - not syncing: Fatal exception in interrupt
Rebooting in 180 seconds..
]
Then the natural solution would be 'stop driver/device then adjust
ring buffer parameter then reactivate driver/device'.
v1: add roll back branch for 'auto reopen fail' statement
Signed-off-by: Liang Li <liang...@windriver.com>
---
drivers/net/ucc_geth.c | 4 ++--
drivers/net/ucc_geth.h | 2 ++
drivers/net/ucc_geth_ethtool.c | 29 +++++++++++++++++++++++------
3 files changed, 27 insertions(+), 8 deletions(-)
diff --git a/drivers/net/ucc_geth.c b/drivers/net/ucc_geth.c
index 7d2e33a..5eadfa3 100644
--- a/drivers/net/ucc_geth.c
+++ b/drivers/net/ucc_geth.c
@@ -3485,7 +3485,7 @@ err:
/* Called when something needs to use the ethernet device */
/* Returns 0 for success. */
-static int ucc_geth_open(struct net_device *dev)
+int ucc_geth_open(struct net_device *dev)
{
struct ucc_geth_private *ugeth = netdev_priv(dev);
int err;
@@ -3542,7 +3542,7 @@ err:
}
/* Stops the kernel queue, and halts the controller */
-static int ucc_geth_close(struct net_device *dev)
+int ucc_geth_close(struct net_device *dev)
{
struct ucc_geth_private *ugeth = netdev_priv(dev);
diff --git a/drivers/net/ucc_geth.h b/drivers/net/ucc_geth.h
index 05a9558..1cfb400 100644
--- a/drivers/net/ucc_geth.h
+++ b/drivers/net/ucc_geth.h
@@ -1235,5 +1235,7 @@ int init_flow_control_params(u32
automatic_flow_control_mode,
u32 __iomem *upsmr_register, u32 __iomem *uempr_register,
u32 __iomem *maccfg1_register);
+extern int ucc_geth_open(struct net_device *);
+extern int ucc_geth_close(struct net_device *);
#endif /* __UCC_GETH_H__ */
diff --git a/drivers/net/ucc_geth_ethtool.c b/drivers/net/ucc_geth_ethtool.c
index 6f92e48..644a6db 100644
--- a/drivers/net/ucc_geth_ethtool.c
+++ b/drivers/net/ucc_geth_ethtool.c
@@ -255,13 +255,30 @@ uec_set_ringparam(struct net_device *netdev,
return -EINVAL;
}
- ug_info->bdRingLenRx[queue] = ring->rx_pending;
- ug_info->bdRingLenTx[queue] = ring->tx_pending;
-
if (netif_running(netdev)) {
- /* FIXME: restart automatically */
- printk(KERN_INFO
- "Please re-open the interface.\n");
+ u16 rx_t;
+ u16 tx_t;
+ printk(KERN_INFO "Stopping interface %s.\n", netdev->name);
+ ucc_geth_close(netdev);
+
+ rx_t = ug_info->bdRingLenRx[queue];
+ tx_t = ug_info->bdRingLenTx[queue];
+
+ ug_info->bdRingLenRx[queue] = ring->rx_pending;
+ ug_info->bdRingLenTx[queue] = ring->tx_pending;
+
+ printk(KERN_INFO "Reactivating interface %s.\n", netdev->name);
+ ret = ucc_geth_open(netdev);
+ if (ret) {
+ printk(KERN_WARNING "uec_set_ringparam: set ring param
for running"
+ " interface %s failed. Please try to
make the interface "
+ " down, then try again.\n",
netdev->name);
+ ug_info->bdRingLenRx[queue] = rx_t;
+ ug_info->bdRingLenTx[queue] = tx_t;
+ }
+ } else {
+ ug_info->bdRingLenRx[queue] = ring->rx_pending;
+ ug_info->bdRingLenTx[queue] = ring->tx_pending;
}
return ret;
--
1.7.2
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