@@ -733,10 +733,17 @@ static pci_ers_result_t common_process(struct pcistub_device *psdev,
wmb();
notify_remote_via_irq(pdev->evtchn_irq);
+ /* Enable IRQ to signal "request done". */
+ xen_pcibk_lateeoi(pdev, 0);
+
ret = wait_event_timeout(xen_pcibk_aer_wait_queue,
!(test_bit(_XEN_PCIB_active, (unsigned long *)
&sh_info->flags)), 300*HZ);
+ /* Enable IRQ for pcifront request if not already active. */
+ if (!test_bit(_PDEVF_op_active, &pdev->flags))
+ xen_pcibk_lateeoi(pdev, 0);
+
if (!ret) {
if (test_bit(_XEN_PCIB_active,
(unsigned long *)&sh_info->flags)) {
@@ -750,13 +757,6 @@ static pci_ers_result_t common_process(struct pcistub_device *psdev,
}
clear_bit(_PCIB_op_pending, (unsigned long *)&pdev->flags);
- if (test_bit(_XEN_PCIF_active,
- (unsigned long *)&sh_info->flags)) {
- dev_dbg(&psdev->dev->dev,
- "schedule pci_conf service in " DRV_NAME "\n");
- xen_pcibk_test_and_schedule_op(psdev->pdev);
- }
-
res = (pci_ers_result_t)aer_op->err;
return res;
}
@@ -14,6 +14,7 @@
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include <linux/atomic.h>
+#include <xen/events.h>
#include <xen/interface/io/pciif.h>
#define DRV_NAME "xen-pciback"
@@ -27,6 +28,8 @@ struct pci_dev_entry {
#define PDEVF_op_active (1<<(_PDEVF_op_active))
#define _PCIB_op_pending (1)
#define PCIB_op_pending (1<<(_PCIB_op_pending))
+#define _EOI_pending (2)
+#define EOI_pending (1<<(_EOI_pending))
struct xen_pcibk_device {
void *pci_dev_data;
@@ -182,12 +185,17 @@ static inline void xen_pcibk_release_devices(struct xen_pcibk_device *pdev)
irqreturn_t xen_pcibk_handle_event(int irq, void *dev_id);
void xen_pcibk_do_op(struct work_struct *data);
+static inline void xen_pcibk_lateeoi(struct xen_pcibk_device *pdev,
+ unsigned int eoi_flag)
+{
+ if (test_and_clear_bit(_EOI_pending, &pdev->flags))
+ xen_irq_lateeoi(pdev->evtchn_irq, eoi_flag);
+}
+
int xen_pcibk_xenbus_register(void);
void xen_pcibk_xenbus_unregister(void);
extern int verbose_request;
-
-void xen_pcibk_test_and_schedule_op(struct xen_pcibk_device *pdev);
#endif
/* Handles shared IRQs that can to device domain and control domain. */
@@ -297,26 +297,41 @@ int xen_pcibk_disable_msix(struct xen_pcibk_device *pdev,
return 0;
}
#endif
+
+static inline bool xen_pcibk_test_op_pending(struct xen_pcibk_device *pdev)
+{
+ return test_bit(_XEN_PCIF_active,
+ (unsigned long *)&pdev->sh_info->flags) &&
+ !test_and_set_bit(_PDEVF_op_active, &pdev->flags);
+}
+
/*
* Now the same evtchn is used for both pcifront conf_read_write request
* as well as pcie aer front end ack. We use a new work_queue to schedule
* xen_pcibk conf_read_write service for avoiding confict with aer_core
* do_recovery job which also use the system default work_queue
*/
-void xen_pcibk_test_and_schedule_op(struct xen_pcibk_device *pdev)
+static void xen_pcibk_test_and_schedule_op(struct xen_pcibk_device *pdev)
{
+ bool eoi = true;
+
/* Check that frontend is requesting an operation and that we are not
* already processing a request */
- if (test_bit(_XEN_PCIF_active, (unsigned long *)&pdev->sh_info->flags)
- && !test_and_set_bit(_PDEVF_op_active, &pdev->flags)) {
+ if (xen_pcibk_test_op_pending(pdev)) {
schedule_work(&pdev->op_work);
+ eoi = false;
}
/*_XEN_PCIB_active should have been cleared by pcifront. And also make
sure xen_pcibk is waiting for ack by checking _PCIB_op_pending*/
if (!test_bit(_XEN_PCIB_active, (unsigned long *)&pdev->sh_info->flags)
&& test_bit(_PCIB_op_pending, &pdev->flags)) {
wake_up(&xen_pcibk_aer_wait_queue);
+ eoi = false;
}
+
+ /* EOI if there was nothing to do. */
+ if (eoi)
+ xen_pcibk_lateeoi(pdev, XEN_EOI_FLAG_SPURIOUS);
}
/* Performing the configuration space reads/writes must not be done in atomic
@@ -324,10 +339,8 @@ void xen_pcibk_test_and_schedule_op(struct xen_pcibk_device *pdev)
* use of semaphores). This function is intended to be called from a work
* queue in process context taking a struct xen_pcibk_device as a parameter */
-void xen_pcibk_do_op(struct work_struct *data)
+static void xen_pcibk_do_one_op(struct xen_pcibk_device *pdev)
{
- struct xen_pcibk_device *pdev =
- container_of(data, struct xen_pcibk_device, op_work);
struct pci_dev *dev;
struct xen_pcibk_dev_data *dev_data = NULL;
struct xen_pci_op *op = &pdev->op;
@@ -400,16 +413,31 @@ void xen_pcibk_do_op(struct work_struct *data)
smp_mb__before_atomic(); /* /after/ clearing PCIF_active */
clear_bit(_PDEVF_op_active, &pdev->flags);
smp_mb__after_atomic(); /* /before/ final check for work */
+}
- /* Check to see if the driver domain tried to start another request in
- * between clearing _XEN_PCIF_active and clearing _PDEVF_op_active.
- */
- xen_pcibk_test_and_schedule_op(pdev);
+void xen_pcibk_do_op(struct work_struct *data)
+{
+ struct xen_pcibk_device *pdev =
+ container_of(data, struct xen_pcibk_device, op_work);
+
+ do {
+ xen_pcibk_do_one_op(pdev);
+ } while (xen_pcibk_test_op_pending(pdev));
+
+ xen_pcibk_lateeoi(pdev, 0);
}
irqreturn_t xen_pcibk_handle_event(int irq, void *dev_id)
{
struct xen_pcibk_device *pdev = dev_id;
+ bool eoi;
+
+ /* IRQs might come in before pdev->evtchn_irq is written. */
+ if (unlikely(pdev->evtchn_irq != irq))
+ pdev->evtchn_irq = irq;
+
+ eoi = test_and_set_bit(_EOI_pending, &pdev->flags);
+ WARN(eoi, "IRQ while EOI pending\n");
xen_pcibk_test_and_schedule_op(pdev);
@@ -123,7 +123,7 @@ static int xen_pcibk_do_attach(struct xen_pcibk_device *pdev, int gnt_ref,
pdev->sh_info = vaddr;
- err = bind_interdomain_evtchn_to_irqhandler(
+ err = bind_interdomain_evtchn_to_irqhandler_lateeoi(
pdev->xdev->otherend_id, remote_evtchn, xen_pcibk_handle_event,
0, DRV_NAME, pdev);
if (err < 0) {