On Wed, 24 Apr 2019 16:45:45 +0000
<Alex_Gagniuc@xxxxxxxxxxxx> wrote:
On 4/23/2019 5:42 PM, Alex Williamson wrote:
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 7e12d0163863..233cd4b5b6e8 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -2403,6 +2403,19 @@ void pcie_report_downtraining(struct pci_dev *dev)
I don't think you want to change pcie_report_downtraining(). You're
advertising to "report" something, by nomenclature, but then go around
and also call a notification callback. This is also used during probe,
and you've now just killed your chance to notice you've booted with a
degraded link.
If what you want to do is silence the bandwidth notification, you want
to modify the threaded interrupt that calls this.
During probe, ie. discovery, a device wouldn't have a driver attached,
so we'd fall through to simply printing the link status. Nothing
lost afaict. The "report" verb doesn't have a subject here, report to
whom? Therefore I thought it reasonable that a driver ask that it be
reported to them via a callback. I don't see that as such a stretch of
the interface.
[snip bad code]if (PCI_FUNC(dev->devfn) != 0 || dev->is_virtfn)
return;
+ /*
+ * If driver handles link_change event, defer to driver. PCIe drivers
+ * can call pcie_print_link_status() to print current link info.
+ */
+ device_lock(&dev->dev);
+ if (dev->driver && dev->driver->err_handler &&
+ dev->driver->err_handler->link_change) {
+ dev->driver->err_handler->link_change(dev);
+ device_unlock(&dev->dev);
+ return;
+ }
+ device_unlock(&dev->dev);
Can we write this such that there is a single lock()/unlock() pair?
Not without introducing a tracking variable, ex.
That's not markedly better imo, but if it's preferred I can send a v2.
AlexAlex