lkml.org 
[lkml]   [2018]   [Mar]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH net v3] net: phy: Tell caller result of phy_change()
Date
In 664fcf123a30e (net: phy: Threaded interrupts allow some simplification)
the phy_interrupt system was changed to use a traditional threaded
interrupt scheme instead of a workqueue approach.

With this change, the phy status check moved into phy_change, which
did not report back to the caller whether or not the interrupt was
handled. This means that, in the case of a shared phy interrupt,
only the first phydev's interrupt registers are checked (since
phy_interrupt() would always return IRQ_HANDLED). This leads to
interrupt storms when it is a secondary device that's actually the
interrupt source.

Signed-off-by: Brad Mouring <brad.mouring@ni.com>
---
drivers/net/phy/phy.c | 145 +++++++++++++++++++++++++-------------------------
include/linux/phy.h | 1 -
2 files changed, 72 insertions(+), 74 deletions(-)

diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index e3e29c2b028b..dfff2cff7da9 100644
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -617,6 +617,77 @@ static void phy_error(struct phy_device *phydev)
phy_trigger_machine(phydev, false);
}

+/**
+ * phy_disable_interrupts - Disable the PHY interrupts from the PHY side
+ * @phydev: target phy_device struct
+ */
+static int phy_disable_interrupts(struct phy_device *phydev)
+{
+ int err;
+
+ /* Disable PHY interrupts */
+ err = phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
+ if (err)
+ goto phy_err;
+
+ /* Clear the interrupt */
+ err = phy_clear_interrupt(phydev);
+ if (err)
+ goto phy_err;
+
+ return 0;
+
+phy_err:
+ phy_error(phydev);
+
+ return err;
+}
+
+/**
+ * phy_change - Called by the phy_interrupt to handle PHY changes
+ * @phydev: phy_device struct that interrupted
+ */
+static irqreturn_t phy_change(struct phy_device *phydev)
+{
+ if (phy_interrupt_is_valid(phydev)) {
+ if (phydev->drv->did_interrupt &&
+ !phydev->drv->did_interrupt(phydev))
+ return IRQ_NONE;
+
+ if (phydev->state == PHY_HALTED)
+ if (phy_disable_interrupts(phydev))
+ goto phy_err;
+ }
+
+ mutex_lock(&phydev->lock);
+ if ((PHY_RUNNING == phydev->state) || (PHY_NOLINK == phydev->state))
+ phydev->state = PHY_CHANGELINK;
+ mutex_unlock(&phydev->lock);
+
+ /* reschedule state queue work to run as soon as possible */
+ phy_trigger_machine(phydev, true);
+
+ if (phy_interrupt_is_valid(phydev) && phy_clear_interrupt(phydev))
+ goto phy_err;
+ return IRQ_HANDLED;
+
+phy_err:
+ phy_error(phydev);
+ return IRQ_NONE;
+}
+
+/**
+ * phy_change_work - Scheduled by the phy_mac_interrupt to handle PHY changes
+ * @work: work_struct that describes the work to be done
+ */
+void phy_change_work(struct work_struct *work)
+{
+ struct phy_device *phydev =
+ container_of(work, struct phy_device, phy_queue);
+
+ phy_change(phydev);
+}
+
/**
* phy_interrupt - PHY interrupt handler
* @irq: interrupt line
@@ -632,9 +703,7 @@ static irqreturn_t phy_interrupt(int irq, void *phy_dat)
if (PHY_HALTED == phydev->state)
return IRQ_NONE; /* It can't be ours. */

- phy_change(phydev);
-
- return IRQ_HANDLED;
+ return phy_change(phydev);
}

/**
@@ -651,32 +720,6 @@ static int phy_enable_interrupts(struct phy_device *phydev)
return phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
}

-/**
- * phy_disable_interrupts - Disable the PHY interrupts from the PHY side
- * @phydev: target phy_device struct
- */
-static int phy_disable_interrupts(struct phy_device *phydev)
-{
- int err;
-
- /* Disable PHY interrupts */
- err = phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
- if (err)
- goto phy_err;
-
- /* Clear the interrupt */
- err = phy_clear_interrupt(phydev);
- if (err)
- goto phy_err;
-
- return 0;
-
-phy_err:
- phy_error(phydev);
-
- return err;
-}
-
/**
* phy_start_interrupts - request and enable interrupts for a PHY device
* @phydev: target phy_device struct
@@ -719,50 +762,6 @@ int phy_stop_interrupts(struct phy_device *phydev)
}
EXPORT_SYMBOL(phy_stop_interrupts);

-/**
- * phy_change - Called by the phy_interrupt to handle PHY changes
- * @phydev: phy_device struct that interrupted
- */
-void phy_change(struct phy_device *phydev)
-{
- if (phy_interrupt_is_valid(phydev)) {
- if (phydev->drv->did_interrupt &&
- !phydev->drv->did_interrupt(phydev))
- return;
-
- if (phydev->state == PHY_HALTED)
- if (phy_disable_interrupts(phydev))
- goto phy_err;
- }
-
- mutex_lock(&phydev->lock);
- if ((PHY_RUNNING == phydev->state) || (PHY_NOLINK == phydev->state))
- phydev->state = PHY_CHANGELINK;
- mutex_unlock(&phydev->lock);
-
- /* reschedule state queue work to run as soon as possible */
- phy_trigger_machine(phydev, true);
-
- if (phy_interrupt_is_valid(phydev) && phy_clear_interrupt(phydev))
- goto phy_err;
- return;
-
-phy_err:
- phy_error(phydev);
-}
-
-/**
- * phy_change_work - Scheduled by the phy_mac_interrupt to handle PHY changes
- * @work: work_struct that describes the work to be done
- */
-void phy_change_work(struct work_struct *work)
-{
- struct phy_device *phydev =
- container_of(work, struct phy_device, phy_queue);
-
- phy_change(phydev);
-}
-
/**
* phy_stop - Bring down the PHY link, and stop checking the status
* @phydev: target phy_device struct
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 5a0c3e53e7c2..2e55838655b9 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -1011,7 +1011,6 @@ int phy_driver_register(struct phy_driver *new_driver, struct module *owner);
int phy_drivers_register(struct phy_driver *new_driver, int n,
struct module *owner);
void phy_state_machine(struct work_struct *work);
-void phy_change(struct phy_device *phydev);
void phy_change_work(struct work_struct *work);
void phy_mac_interrupt(struct phy_device *phydev);
void phy_start_machine(struct phy_device *phydev);
--
2.16.2
\
 
 \ /
  Last update: 2018-03-08 23:24    [W:0.067 / U:18.748 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site