* [Qemu-devel] [PATCH] pci: Fix INTx routing notifier recursion
@ 2013-03-07 18:29 Alex Williamson
2013-03-07 18:47 ` Michael S. Tsirkin
0 siblings, 1 reply; 2+ messages in thread
From: Alex Williamson @ 2013-03-07 18:29 UTC (permalink / raw)
To: mst; +Cc: qemu-devel
For some reason we recurse to fire the INTx routing notifier for each
child of a bus, for each possible device of a bus. That means that if
we add a root port, the notifier gets called for that bridge 256
times. If we add an upstream switch behind that root port, 256^2. But
of course we need a downstream switch, 256^3. This starts to be
noticeable. Stop the insanity.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
---
hw/pci/pci.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index 8772707..f24c389 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -1215,9 +1215,10 @@ void pci_bus_fire_intx_routing_notifier(PCIBus *bus)
if (dev && dev->intx_routing_notifier) {
dev->intx_routing_notifier(dev);
}
- QLIST_FOREACH(sec, &bus->child, sibling) {
- pci_bus_fire_intx_routing_notifier(sec);
- }
+ }
+
+ QLIST_FOREACH(sec, &bus->child, sibling) {
+ pci_bus_fire_intx_routing_notifier(sec);
}
}
^ permalink raw reply related [flat|nested] 2+ messages in thread* Re: [Qemu-devel] [PATCH] pci: Fix INTx routing notifier recursion
2013-03-07 18:29 [Qemu-devel] [PATCH] pci: Fix INTx routing notifier recursion Alex Williamson
@ 2013-03-07 18:47 ` Michael S. Tsirkin
0 siblings, 0 replies; 2+ messages in thread
From: Michael S. Tsirkin @ 2013-03-07 18:47 UTC (permalink / raw)
To: Alex Williamson; +Cc: qemu-devel
On Thu, Mar 07, 2013 at 11:29:19AM -0700, Alex Williamson wrote:
> For some reason we recurse to fire the INTx routing notifier for each
> child of a bus, for each possible device of a bus. That means that if
> we add a root port, the notifier gets called for that bridge 256
> times. If we add an upstream switch behind that root port, 256^2. But
> of course we need a downstream switch, 256^3. This starts to be
> noticeable. Stop the insanity.
>
> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Applied, thanks.
> ---
> hw/pci/pci.c | 7 ++++---
> 1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> index 8772707..f24c389 100644
> --- a/hw/pci/pci.c
> +++ b/hw/pci/pci.c
> @@ -1215,9 +1215,10 @@ void pci_bus_fire_intx_routing_notifier(PCIBus *bus)
> if (dev && dev->intx_routing_notifier) {
> dev->intx_routing_notifier(dev);
> }
> - QLIST_FOREACH(sec, &bus->child, sibling) {
> - pci_bus_fire_intx_routing_notifier(sec);
> - }
> + }
> +
> + QLIST_FOREACH(sec, &bus->child, sibling) {
> + pci_bus_fire_intx_routing_notifier(sec);
> }
> }
>
^ permalink raw reply [flat|nested] 2+ messages in thread
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2013-03-07 18:29 [Qemu-devel] [PATCH] pci: Fix INTx routing notifier recursion Alex Williamson
2013-03-07 18:47 ` Michael S. Tsirkin
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