[PATCH 4.9 068/108] r8152: avoid start_xmit to call napi_schedule during autosuspend

Greg Kroah-Hartman
2017-06-15T18:12:02Z

From: hayeswang <hayeswang@realtek.com>

[ Upstream commit 26afec39306926654e9cd320f19bbf3685bb0997 ]

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@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/usb/r8152.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)

--- a/drivers/net/usb/r8152.c
+++ b/drivers/net/usb/r8152.c
@@ -3583,10 +3583,15 @@ static int rtl8152_rumtime_suspend(struc
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;
}
@@ -3603,6 +3608,8 @@ static int rtl8152_rumtime_suspend(struc
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;
}
@@ -3622,8 +3629,6 @@ static int rtl8152_rumtime_suspend(struc
}
}

- set_bit(SELECTIVE_SUSPEND, &tp->flags);
-
out1:
return ret;
}
@@ -3679,12 +3684,13 @@ static int rtl8152_resume(struct usb_int
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);