[PATCH net v2 1/4] r8152: avoid start_xmit to call napi_schedule during autosuspend

From: Hayes Wang
Date: Wed Jan 25 2017 - 03:14:32 EST


Adjust the setting of the flag of SELECTIVE_SUSPEND to prevent start_xmit()
from calling napi_schedule() directly during runtime suspend.

After calling napi_disable() or clearing the flag of WORK_ENABLE,
scheduling the napi is useless.

Signed-off-by: Hayes Wang <hayeswang@xxxxxxxxxxx>
---
drivers/net/usb/r8152.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c
index e1466b4..23bef8e 100644
--- a/drivers/net/usb/r8152.c
+++ b/drivers/net/usb/r8152.c
@@ -3585,10 +3585,15 @@ static int rtl8152_rumtime_suspend(struct r8152 *tp)
struct net_device *netdev = tp->netdev;
int ret = 0;

+ set_bit(SELECTIVE_SUSPEND, &tp->flags);
+ smp_mb__after_atomic();
+
if (netif_running(netdev) && test_bit(WORK_ENABLE, &tp->flags)) {
u32 rcr = 0;

if (delay_autosuspend(tp)) {
+ clear_bit(SELECTIVE_SUSPEND, &tp->flags);
+ smp_mb__after_atomic();
ret = -EBUSY;
goto out1;
}
@@ -3605,6 +3610,8 @@ static int rtl8152_rumtime_suspend(struct r8152 *tp)
if (!(ocp_data & RXFIFO_EMPTY)) {
rxdy_gated_en(tp, false);
ocp_write_dword(tp, MCU_TYPE_PLA, PLA_RCR, rcr);
+ clear_bit(SELECTIVE_SUSPEND, &tp->flags);
+ smp_mb__after_atomic();
ret = -EBUSY;
goto out1;
}
@@ -3624,8 +3631,6 @@ static int rtl8152_rumtime_suspend(struct r8152 *tp)
}
}

- set_bit(SELECTIVE_SUSPEND, &tp->flags);
-
out1:
return ret;
}
@@ -3681,12 +3686,13 @@ static int rtl8152_resume(struct usb_interface *intf)
if (netif_running(tp->netdev) && tp->netdev->flags & IFF_UP) {
if (test_bit(SELECTIVE_SUSPEND, &tp->flags)) {
tp->rtl_ops.autosuspend_en(tp, false);
- clear_bit(SELECTIVE_SUSPEND, &tp->flags);
napi_disable(&tp->napi);
set_bit(WORK_ENABLE, &tp->flags);
if (netif_carrier_ok(tp->netdev))
rtl_start_rx(tp);
napi_enable(&tp->napi);
+ clear_bit(SELECTIVE_SUSPEND, &tp->flags);
+ smp_mb__after_atomic();
} else {
tp->rtl_ops.up(tp);
netif_carrier_off(tp->netdev);
--
2.7.4