* [PATCH v3 1/1 net] net: fec: fix kernel oops when plug/unplug cable many times
@ 2013-05-02 0:55 Frank Li
2013-05-02 20:48 ` David Miller
2013-05-06 9:19 ` Lucas Stach
0 siblings, 2 replies; 6+ messages in thread
From: Frank Li @ 2013-05-02 0:55 UTC (permalink / raw)
To: romieu, r.schwebel, davem, l.stach, netdev, festevam, shawn.guo,
lznuaa
Cc: Frank Li
reproduce steps
1. flood ping from other machine
ping -f -s 41000 IP
2. run below script
while [ 1 ]; do ethtool -s eth0 autoneg off;
sleep 3;ethtool -s eth0 autoneg on; sleep 4; done;
You can see oops in one hour.
The reason is fec_restart clear BD but NAPI may use it.
The solution is disable NAPI and stop xmit when reset BD.
disable NAPI may sleep, so fec_restart can't be call in
atomic context.
Signed-off-by: Frank Li <Frank.Li@freescale.com>
---
Change from v1 to v2
* Add netif_tx_lock(ndev) to avoid xmit runing when reset hardware
Change from v2 to v3
* Move put real statements after function variable declarations according to David's comments
* Remove lock in adjust_link according to Lucas Stach's comments
drivers/net/ethernet/freescale/fec.c | 42 +++++++++++++++++++++++++---------
drivers/net/ethernet/freescale/fec.h | 3 +-
2 files changed, 33 insertions(+), 12 deletions(-)
diff --git a/drivers/net/ethernet/freescale/fec.c b/drivers/net/ethernet/freescale/fec.c
index 73195f6..5a9345c 100644
--- a/drivers/net/ethernet/freescale/fec.c
+++ b/drivers/net/ethernet/freescale/fec.c
@@ -407,6 +407,12 @@ fec_restart(struct net_device *ndev, int duplex)
u32 rcntl = OPT_FRAME_SIZE | 0x04;
u32 ecntl = 0x2; /* ETHEREN */
+ if (netif_running(ndev)) {
+ napi_disable(&fep->napi);
+ netif_stop_queue(ndev);
+ netif_tx_lock(ndev);
+ }
+
/* Whack a reset. We should wait for this. */
writel(1, fep->hwp + FEC_ECNTRL);
udelay(10);
@@ -559,6 +565,12 @@ fec_restart(struct net_device *ndev, int duplex)
/* Enable interrupts we wish to service */
writel(FEC_DEFAULT_IMASK, fep->hwp + FEC_IMASK);
+
+ if (netif_running(ndev)) {
+ napi_enable(&fep->napi);
+ netif_wake_queue(ndev);
+ netif_tx_unlock(ndev);
+ }
}
static void
@@ -598,8 +610,20 @@ fec_timeout(struct net_device *ndev)
ndev->stats.tx_errors++;
- fec_restart(ndev, fep->full_duplex);
- netif_wake_queue(ndev);
+ fep->timeout = 1;
+ schedule_delayed_work(&fep->delay_work, msecs_to_jiffies(1));
+}
+
+static void fec_enet_work(struct work_struct *work)
+{
+ struct fec_enet_private *fep =
+ container_of(work, struct fec_enet_private, delay_work.work);
+
+ if (fep->timeout) {
+ fep->timeout = 0;
+ fec_restart(fep->netdev, fep->full_duplex);
+ netif_wake_queue(fep->netdev);
+ }
}
static void
@@ -970,16 +994,12 @@ static void fec_enet_adjust_link(struct net_device *ndev)
{
struct fec_enet_private *fep = netdev_priv(ndev);
struct phy_device *phy_dev = fep->phy_dev;
- unsigned long flags;
-
int status_change = 0;
- spin_lock_irqsave(&fep->hw_lock, flags);
-
/* Prevent a state halted on mii error */
if (fep->mii_timeout && phy_dev->state == PHY_HALTED) {
phy_dev->state = PHY_RESUMING;
- goto spin_unlock;
+ goto exit;
}
if (phy_dev->link) {
@@ -995,7 +1015,6 @@ static void fec_enet_adjust_link(struct net_device *ndev)
fep->speed = phy_dev->speed;
status_change = 1;
}
-
/* if any of the above changed restart the FEC */
if (status_change)
fec_restart(ndev, phy_dev->duplex);
@@ -1007,11 +1026,10 @@ static void fec_enet_adjust_link(struct net_device *ndev)
}
}
-spin_unlock:
- spin_unlock_irqrestore(&fep->hw_lock, flags);
-
+exit:
if (status_change)
phy_print_status(phy_dev);
+
}
static int fec_enet_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
@@ -1882,6 +1900,7 @@ fec_probe(struct platform_device *pdev)
if (ret)
goto failed_register;
+ INIT_DELAYED_WORK(&fep->delay_work, fec_enet_work);
return 0;
failed_register:
@@ -1918,6 +1937,7 @@ fec_drv_remove(struct platform_device *pdev)
struct resource *r;
int i;
+ cancel_delayed_work_sync(&fep->delay_work);
unregister_netdev(ndev);
fec_enet_mii_remove(fep);
del_timer_sync(&fep->time_keep);
diff --git a/drivers/net/ethernet/freescale/fec.h b/drivers/net/ethernet/freescale/fec.h
index eb43729..a367b21 100644
--- a/drivers/net/ethernet/freescale/fec.h
+++ b/drivers/net/ethernet/freescale/fec.h
@@ -260,7 +260,8 @@ struct fec_enet_private {
int hwts_rx_en;
int hwts_tx_en;
struct timer_list time_keep;
-
+ struct delayed_work delay_work;
+ int timeout;
};
void fec_ptp_init(struct net_device *ndev, struct platform_device *pdev);
--
1.7.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH v3 1/1 net] net: fec: fix kernel oops when plug/unplug cable many times 2013-05-02 0:55 [PATCH v3 1/1 net] net: fec: fix kernel oops when plug/unplug cable many times Frank Li @ 2013-05-02 20:48 ` David Miller 2013-05-06 7:47 ` Frank Li 2013-05-06 9:19 ` Lucas Stach 1 sibling, 1 reply; 6+ messages in thread From: David Miller @ 2013-05-02 20:48 UTC (permalink / raw) To: Frank.Li; +Cc: romieu, r.schwebel, l.stach, netdev, festevam, shawn.guo, lznuaa From: Frank Li <Frank.Li@freescale.com> Date: Thu, 2 May 2013 08:55:38 +0800 > reproduce steps > 1. flood ping from other machine > ping -f -s 41000 IP > 2. run below script > while [ 1 ]; do ethtool -s eth0 autoneg off; > sleep 3;ethtool -s eth0 autoneg on; sleep 4; done; > > You can see oops in one hour. > > The reason is fec_restart clear BD but NAPI may use it. > The solution is disable NAPI and stop xmit when reset BD. > disable NAPI may sleep, so fec_restart can't be call in > atomic context. > > Signed-off-by: Frank Li <Frank.Li@freescale.com> Please respin this against the current 'net' tree. Thanks! ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v3 1/1 net] net: fec: fix kernel oops when plug/unplug cable many times 2013-05-02 20:48 ` David Miller @ 2013-05-06 7:47 ` Frank Li 0 siblings, 0 replies; 6+ messages in thread From: Frank Li @ 2013-05-06 7:47 UTC (permalink / raw) To: David Miller Cc: Frank.Li@freescale.com, Francois Romieu, Robert Schwebel, Lucas Stach, netdev@vger.kernel.org, Fabio Estevam, Shawn Guo 2013/5/3 David Miller <davem@davemloft.net>: > From: Frank Li <Frank.Li@freescale.com> > Date: Thu, 2 May 2013 08:55:38 +0800 > >> reproduce steps >> 1. flood ping from other machine >> ping -f -s 41000 IP >> 2. run below script >> while [ 1 ]; do ethtool -s eth0 autoneg off; >> sleep 3;ethtool -s eth0 autoneg on; sleep 4; done; >> >> You can see oops in one hour. >> >> The reason is fec_restart clear BD but NAPI may use it. >> The solution is disable NAPI and stop xmit when reset BD. >> disable NAPI may sleep, so fec_restart can't be call in >> atomic context. >> >> Signed-off-by: Frank Li <Frank.Li@freescale.com> > > Please respin this against the current 'net' tree. MX6 can't bootup at net and net-next tree. I am identifying the reason. > > Thanks! ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v3 1/1 net] net: fec: fix kernel oops when plug/unplug cable many times 2013-05-02 0:55 [PATCH v3 1/1 net] net: fec: fix kernel oops when plug/unplug cable many times Frank Li 2013-05-02 20:48 ` David Miller @ 2013-05-06 9:19 ` Lucas Stach 2013-05-06 9:56 ` Frank Li 1 sibling, 1 reply; 6+ messages in thread From: Lucas Stach @ 2013-05-06 9:19 UTC (permalink / raw) To: Frank Li; +Cc: romieu, r.schwebel, davem, netdev, festevam, shawn.guo, lznuaa Hi Frank, Am Donnerstag, den 02.05.2013, 08:55 +0800 schrieb Frank Li: > reproduce steps > 1. flood ping from other machine > ping -f -s 41000 IP > 2. run below script > while [ 1 ]; do ethtool -s eth0 autoneg off; > sleep 3;ethtool -s eth0 autoneg on; sleep 4; done; > > You can see oops in one hour. > > The reason is fec_restart clear BD but NAPI may use it. > The solution is disable NAPI and stop xmit when reset BD. > disable NAPI may sleep, so fec_restart can't be call in > atomic context. > > Signed-off-by: Frank Li <Frank.Li@freescale.com> > --- > Change from v1 to v2 > * Add netif_tx_lock(ndev) to avoid xmit runing when reset hardware > Change from v2 to v3 > * Move put real statements after function variable declarations according to David's comments > * Remove lock in adjust_link according to Lucas Stach's comments > > drivers/net/ethernet/freescale/fec.c | 42 +++++++++++++++++++++++++--------- > drivers/net/ethernet/freescale/fec.h | 3 +- > 2 files changed, 33 insertions(+), 12 deletions(-) > > diff --git a/drivers/net/ethernet/freescale/fec.c b/drivers/net/ethernet/freescale/fec.c > index 73195f6..5a9345c 100644 > --- a/drivers/net/ethernet/freescale/fec.c > +++ b/drivers/net/ethernet/freescale/fec.c > @@ -407,6 +407,12 @@ fec_restart(struct net_device *ndev, int duplex) > u32 rcntl = OPT_FRAME_SIZE | 0x04; > u32 ecntl = 0x2; /* ETHEREN */ > > + if (netif_running(ndev)) { > + napi_disable(&fep->napi); > + netif_stop_queue(ndev); > + netif_tx_lock(ndev); > + } > + You did not address the comment from Ben Hutchings here. To make sure we are not triggering the netdev watchdog immediately when calling netif_stop_queue() we must call netif_device_detach() when entering the fec_restart and netif_device_attach() when leaving. fec_restart gets called when duplex or phy speed changes, not only in response to a link up/down change. > /* Whack a reset. We should wait for this. */ > writel(1, fep->hwp + FEC_ECNTRL); > udelay(10); > @@ -559,6 +565,12 @@ fec_restart(struct net_device *ndev, int duplex) > > /* Enable interrupts we wish to service */ > writel(FEC_DEFAULT_IMASK, fep->hwp + FEC_IMASK); > + > + if (netif_running(ndev)) { > + napi_enable(&fep->napi); > + netif_wake_queue(ndev); > + netif_tx_unlock(ndev); > + } > } > > static void > @@ -598,8 +610,20 @@ fec_timeout(struct net_device *ndev) > > ndev->stats.tx_errors++; > > - fec_restart(ndev, fep->full_duplex); > - netif_wake_queue(ndev); > + fep->timeout = 1; > + schedule_delayed_work(&fep->delay_work, msecs_to_jiffies(1)); > +} Okay, I understand you want to reuse this workqueue to do other things which might require delayed work so a delay workqueue is fine, but really use a delay of 0 here. schedule_delayed_work() internally calls down to queue_delayed_work_on() where the documentation states: "If delay is zero and dwork is idle, it will be scheduled for immediate execution.", so this is the right thing to do here. > + > +static void fec_enet_work(struct work_struct *work) > +{ > + struct fec_enet_private *fep = > + container_of(work, struct fec_enet_private, delay_work.work); > + > + if (fep->timeout) { > + fep->timeout = 0; > + fec_restart(fep->netdev, fep->full_duplex); > + netif_wake_queue(fep->netdev); > + } > } > > static void > @@ -970,16 +994,12 @@ static void fec_enet_adjust_link(struct net_device *ndev) > { > struct fec_enet_private *fep = netdev_priv(ndev); > struct phy_device *phy_dev = fep->phy_dev; > - unsigned long flags; > - > int status_change = 0; > > - spin_lock_irqsave(&fep->hw_lock, flags); > - > /* Prevent a state halted on mii error */ > if (fep->mii_timeout && phy_dev->state == PHY_HALTED) { > phy_dev->state = PHY_RESUMING; > - goto spin_unlock; > + goto exit; If we bail out here there is zero chance that we detect a link change, so drop the label and just return here. > } > > if (phy_dev->link) { > @@ -995,7 +1015,6 @@ static void fec_enet_adjust_link(struct net_device *ndev) > fep->speed = phy_dev->speed; > status_change = 1; > } > - Unnecessary whitespace change. > /* if any of the above changed restart the FEC */ > if (status_change) > fec_restart(ndev, phy_dev->duplex); > @@ -1007,11 +1026,10 @@ static void fec_enet_adjust_link(struct net_device *ndev) > } > } > > -spin_unlock: > - spin_unlock_irqrestore(&fep->hw_lock, flags); > - You are eliminating all users of the hw_lock, so please remove it altogether. Eliminate it from the fec_enet_private struct and the init in fec_enet_init(). > +exit: > if (status_change) > phy_print_status(phy_dev); > + > } > > static int fec_enet_mdio_read(struct mii_bus *bus, int mii_id, int regnum) > @@ -1882,6 +1900,7 @@ fec_probe(struct platform_device *pdev) > if (ret) > goto failed_register; > > + INIT_DELAYED_WORK(&fep->delay_work, fec_enet_work); > return 0; > > failed_register: > @@ -1918,6 +1937,7 @@ fec_drv_remove(struct platform_device *pdev) > struct resource *r; > int i; > > + cancel_delayed_work_sync(&fep->delay_work); > unregister_netdev(ndev); > fec_enet_mii_remove(fep); > del_timer_sync(&fep->time_keep); > diff --git a/drivers/net/ethernet/freescale/fec.h b/drivers/net/ethernet/freescale/fec.h > index eb43729..a367b21 100644 > --- a/drivers/net/ethernet/freescale/fec.h > +++ b/drivers/net/ethernet/freescale/fec.h > @@ -260,7 +260,8 @@ struct fec_enet_private { > int hwts_rx_en; > int hwts_tx_en; > struct timer_list time_keep; > - > + struct delayed_work delay_work; > + int timeout; I suspect you are going to add more variables like this in the future if you are using the workqueue more extensively. This is a massive pollution of the fec_enet_private struct. Please make this a bitfield with a proper define for the timeout, so we can reuse one variable for different tasks, or even split this out into it's own struct for the delayed tasks. > }; > > void fec_ptp_init(struct net_device *ndev, struct platform_device *pdev); -- Pengutronix e.K. | Lucas Stach | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-5076 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v3 1/1 net] net: fec: fix kernel oops when plug/unplug cable many times 2013-05-06 9:19 ` Lucas Stach @ 2013-05-06 9:56 ` Frank Li 2013-05-06 10:16 ` Lucas Stach 0 siblings, 1 reply; 6+ messages in thread From: Frank Li @ 2013-05-06 9:56 UTC (permalink / raw) To: Lucas Stach Cc: Frank Li, Francois Romieu, Robert Schwebel, David Miller, netdev@vger.kernel.org, Fabio Estevam, Shawn Guo 2013/5/6 Lucas Stach <l.stach@pengutronix.de>: > Hi Frank, > > Am Donnerstag, den 02.05.2013, 08:55 +0800 schrieb Frank Li: >> reproduce steps >> 1. flood ping from other machine >> ping -f -s 41000 IP >> 2. run below script >> while [ 1 ]; do ethtool -s eth0 autoneg off; >> sleep 3;ethtool -s eth0 autoneg on; sleep 4; done; >> >> You can see oops in one hour. >> >> The reason is fec_restart clear BD but NAPI may use it. >> The solution is disable NAPI and stop xmit when reset BD. >> disable NAPI may sleep, so fec_restart can't be call in >> atomic context. >> >> Signed-off-by: Frank Li <Frank.Li@freescale.com> >> --- >> Change from v1 to v2 >> * Add netif_tx_lock(ndev) to avoid xmit runing when reset hardware >> Change from v2 to v3 >> * Move put real statements after function variable declarations according to David's comments >> * Remove lock in adjust_link according to Lucas Stach's comments >> >> drivers/net/ethernet/freescale/fec.c | 42 +++++++++++++++++++++++++--------- >> drivers/net/ethernet/freescale/fec.h | 3 +- >> 2 files changed, 33 insertions(+), 12 deletions(-) >> >> diff --git a/drivers/net/ethernet/freescale/fec.c b/drivers/net/ethernet/freescale/fec.c >> index 73195f6..5a9345c 100644 >> --- a/drivers/net/ethernet/freescale/fec.c >> +++ b/drivers/net/ethernet/freescale/fec.c >> @@ -407,6 +407,12 @@ fec_restart(struct net_device *ndev, int duplex) >> u32 rcntl = OPT_FRAME_SIZE | 0x04; >> u32 ecntl = 0x2; /* ETHEREN */ >> >> + if (netif_running(ndev)) { >> + napi_disable(&fep->napi); >> + netif_stop_queue(ndev); >> + netif_tx_lock(ndev); >> + } >> + > You did not address the comment from Ben Hutchings here. To make sure we > are not triggering the netdev watchdog immediately when calling > netif_stop_queue() we must call netif_device_detach() when entering the > fec_restart and netif_device_attach() when leaving. Accepted. > > fec_restart gets called when duplex or phy speed changes, not only in > response to a link up/down change. Yes. > >> /* Whack a reset. We should wait for this. */ >> writel(1, fep->hwp + FEC_ECNTRL); >> udelay(10); >> @@ -559,6 +565,12 @@ fec_restart(struct net_device *ndev, int duplex) >> >> /* Enable interrupts we wish to service */ >> writel(FEC_DEFAULT_IMASK, fep->hwp + FEC_IMASK); >> + >> + if (netif_running(ndev)) { >> + napi_enable(&fep->napi); >> + netif_wake_queue(ndev); >> + netif_tx_unlock(ndev); >> + } >> } >> >> static void >> @@ -598,8 +610,20 @@ fec_timeout(struct net_device *ndev) >> >> ndev->stats.tx_errors++; >> >> - fec_restart(ndev, fep->full_duplex); >> - netif_wake_queue(ndev); >> + fep->timeout = 1; >> + schedule_delayed_work(&fep->delay_work, msecs_to_jiffies(1)); >> +} > Okay, I understand you want to reuse this workqueue to do other things > which might require delayed work so a delay workqueue is fine, but > really use a delay of 0 here. > > schedule_delayed_work() internally calls down to queue_delayed_work_on() > where the documentation states: "If delay is zero and dwork is idle, it > will be scheduled for immediate execution.", so this is the right thing > to do here. Accepted. > >> + >> +static void fec_enet_work(struct work_struct *work) >> +{ >> + struct fec_enet_private *fep = >> + container_of(work, struct fec_enet_private, delay_work.work); >> + >> + if (fep->timeout) { >> + fep->timeout = 0; >> + fec_restart(fep->netdev, fep->full_duplex); >> + netif_wake_queue(fep->netdev); >> + } >> } >> >> static void >> @@ -970,16 +994,12 @@ static void fec_enet_adjust_link(struct net_device *ndev) >> { >> struct fec_enet_private *fep = netdev_priv(ndev); >> struct phy_device *phy_dev = fep->phy_dev; >> - unsigned long flags; >> - >> int status_change = 0; >> >> - spin_lock_irqsave(&fep->hw_lock, flags); >> - >> /* Prevent a state halted on mii error */ >> if (fep->mii_timeout && phy_dev->state == PHY_HALTED) { >> phy_dev->state = PHY_RESUMING; >> - goto spin_unlock; >> + goto exit; > If we bail out here there is zero chance that we detect a link change, > so drop the label and just return here. > Accepted >> } >> >> if (phy_dev->link) { >> @@ -995,7 +1015,6 @@ static void fec_enet_adjust_link(struct net_device *ndev) >> fep->speed = phy_dev->speed; >> status_change = 1; >> } >> - > Unnecessary whitespace change. Accepted > >> /* if any of the above changed restart the FEC */ >> if (status_change) >> fec_restart(ndev, phy_dev->duplex); >> @@ -1007,11 +1026,10 @@ static void fec_enet_adjust_link(struct net_device *ndev) >> } >> } >> >> -spin_unlock: >> - spin_unlock_irqrestore(&fep->hw_lock, flags); >> - > You are eliminating all users of the hw_lock, so please remove it > altogether. Eliminate it from the fec_enet_private struct and the init > in fec_enet_init(). Accepted > >> +exit: >> if (status_change) >> phy_print_status(phy_dev); >> + >> } >> >> static int fec_enet_mdio_read(struct mii_bus *bus, int mii_id, int regnum) >> @@ -1882,6 +1900,7 @@ fec_probe(struct platform_device *pdev) >> if (ret) >> goto failed_register; >> >> + INIT_DELAYED_WORK(&fep->delay_work, fec_enet_work); >> return 0; >> >> failed_register: >> @@ -1918,6 +1937,7 @@ fec_drv_remove(struct platform_device *pdev) >> struct resource *r; >> int i; >> >> + cancel_delayed_work_sync(&fep->delay_work); >> unregister_netdev(ndev); >> fec_enet_mii_remove(fep); >> del_timer_sync(&fep->time_keep); >> diff --git a/drivers/net/ethernet/freescale/fec.h b/drivers/net/ethernet/freescale/fec.h >> index eb43729..a367b21 100644 >> --- a/drivers/net/ethernet/freescale/fec.h >> +++ b/drivers/net/ethernet/freescale/fec.h >> @@ -260,7 +260,8 @@ struct fec_enet_private { >> int hwts_rx_en; >> int hwts_tx_en; >> struct timer_list time_keep; >> - >> + struct delayed_work delay_work; >> + int timeout; > I suspect you are going to add more variables like this in the future if > you are using the workqueue more extensively. This is a massive > pollution of the fec_enet_private struct. Please make this a bitfield > with a proper define for the timeout, so we can reuse one variable for > different tasks, or even split this out into it's own struct for the > delayed tasks. Bit | & is not atomic. So I prefer use two variable. the real work in delay work is very simple for future workaround. > >> }; >> >> void fec_ptp_init(struct net_device *ndev, struct platform_device *pdev); > > -- > Pengutronix e.K. | Lucas Stach | > Industrial Linux Solutions | http://www.pengutronix.de/ | > Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-5076 | > Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | > ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v3 1/1 net] net: fec: fix kernel oops when plug/unplug cable many times 2013-05-06 9:56 ` Frank Li @ 2013-05-06 10:16 ` Lucas Stach 0 siblings, 0 replies; 6+ messages in thread From: Lucas Stach @ 2013-05-06 10:16 UTC (permalink / raw) To: Frank Li Cc: Frank Li, Francois Romieu, Robert Schwebel, David Miller, netdev@vger.kernel.org, Fabio Estevam, Shawn Guo Am Montag, den 06.05.2013, 17:56 +0800 schrieb Frank Li: > 2013/5/6 Lucas Stach <l.stach@pengutronix.de>: > > Hi Frank, > > > > Am Donnerstag, den 02.05.2013, 08:55 +0800 schrieb Frank Li: [...] > >> diff --git a/drivers/net/ethernet/freescale/fec.h b/drivers/net/ethernet/freescale/fec.h > >> index eb43729..a367b21 100644 > >> --- a/drivers/net/ethernet/freescale/fec.h > >> +++ b/drivers/net/ethernet/freescale/fec.h > >> @@ -260,7 +260,8 @@ struct fec_enet_private { > >> int hwts_rx_en; > >> int hwts_tx_en; > >> struct timer_list time_keep; > >> - > >> + struct delayed_work delay_work; > >> + int timeout; > > I suspect you are going to add more variables like this in the future if > > you are using the workqueue more extensively. This is a massive > > pollution of the fec_enet_private struct. Please make this a bitfield > > with a proper define for the timeout, so we can reuse one variable for > > different tasks, or even split this out into it's own struct for the > > delayed tasks. > > Bit | & is not atomic. > So I prefer use two variable. the real work in delay work is very > simple for future workaround. Ah yes, that's right. Could you then please change the type of the variable to bool to make it clear that nothing other than true/false should go into this? I would still prefer to group the delayed work related things together in one struct to make the driver more readable overall. Like this: struct fec_delayed_work { struct delayed_work delay_work; bool timeout; bool future_workaround; bool more_delayed_things; }; And just include this struct in fec_enet_private. -- Pengutronix e.K. | Lucas Stach | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-5076 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2013-05-06 10:17 UTC | newest] Thread overview: 6+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2013-05-02 0:55 [PATCH v3 1/1 net] net: fec: fix kernel oops when plug/unplug cable many times Frank Li 2013-05-02 20:48 ` David Miller 2013-05-06 7:47 ` Frank Li 2013-05-06 9:19 ` Lucas Stach 2013-05-06 9:56 ` Frank Li 2013-05-06 10:16 ` Lucas Stach
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for NNTP newsgroup(s).