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[RFC/RFT,v2,3/3] PCI/ACPI: Add ACPI pci_bus_find_numa_node() implementation

Message ID 20170515132205.19622-4-lorenzo.pieralisi@arm.com (mailing list archive)
State New, archived
Delegated to: Bjorn Helgaas
Headers show

Commit Message

Lorenzo Pieralisi May 15, 2017, 1:22 p.m. UTC
The introduction of pci_bus_find_numa_node(pci_bus) allows at PCI
host bridge registration to detect the NUMA node for a given
struct pci_bus.dev. Implement an ACPI method that, through
the struct pci_bus.bridge ACPI companion, retrieve and return
the NUMA node corresponding to a given struct pci_bus.dev.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
---
 drivers/pci/pci-acpi.c | 20 ++++++++++++++++++++
 drivers/pci/pci.c      |  2 +-
 include/linux/pci.h    |  6 ++++++
 3 files changed, 27 insertions(+), 1 deletion(-)

Comments

Richter, Robert May 16, 2017, 3:15 p.m. UTC | #1
On 15.05.17 14:22:05, Lorenzo Pieralisi wrote:
> The introduction of pci_bus_find_numa_node(pci_bus) allows at PCI
> host bridge registration to detect the NUMA node for a given
> struct pci_bus.dev. Implement an ACPI method that, through
> the struct pci_bus.bridge ACPI companion, retrieve and return
> the NUMA node corresponding to a given struct pci_bus.dev.
> 
> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> Cc: Bjorn Helgaas <bhelgaas@google.com>
> ---
>  drivers/pci/pci-acpi.c | 20 ++++++++++++++++++++
>  drivers/pci/pci.c      |  2 +-
>  include/linux/pci.h    |  6 ++++++
>  3 files changed, 27 insertions(+), 1 deletion(-)
> 

> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index e9803c1..451342d 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -5406,7 +5406,7 @@ int pci_bus_find_domain_nr(struct pci_bus *bus, struct device *parent)
>  
>  int pci_bus_find_numa_node(struct pci_bus *bus)
>  {
> -	return NUMA_NO_NODE;
> +	return acpi_disabled ? NUMA_NO_NODE : acpi_pci_bus_find_numa_node(bus);

I looked into how this works with devicetree.

With ACPI it is set directly in pci_register_host_bridge() with
set_dev_node().

For the DT case the set_dev_node call sets it to NUMA_NO_NODE first.
Since in DT the bridge is a platform device which has the node id
assigned already (if there is one), the bus' node id is set later in
device_add() when deriving it from the parent device which is the
bridge. So this should work.

I have tested it both DT and ACPI.

Thanks,

-Robert

>  }
>  
>  /**
Lorenzo Pieralisi May 16, 2017, 6:02 p.m. UTC | #2
On Tue, May 16, 2017 at 05:15:29PM +0200, Robert Richter wrote:
> On 15.05.17 14:22:05, Lorenzo Pieralisi wrote:
> > The introduction of pci_bus_find_numa_node(pci_bus) allows at PCI
> > host bridge registration to detect the NUMA node for a given
> > struct pci_bus.dev. Implement an ACPI method that, through
> > the struct pci_bus.bridge ACPI companion, retrieve and return
> > the NUMA node corresponding to a given struct pci_bus.dev.
> > 
> > Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> > Cc: Bjorn Helgaas <bhelgaas@google.com>
> > ---
> >  drivers/pci/pci-acpi.c | 20 ++++++++++++++++++++
> >  drivers/pci/pci.c      |  2 +-
> >  include/linux/pci.h    |  6 ++++++
> >  3 files changed, 27 insertions(+), 1 deletion(-)
> > 
> 
> > diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> > index e9803c1..451342d 100644
> > --- a/drivers/pci/pci.c
> > +++ b/drivers/pci/pci.c
> > @@ -5406,7 +5406,7 @@ int pci_bus_find_domain_nr(struct pci_bus *bus, struct device *parent)
> >  
> >  int pci_bus_find_numa_node(struct pci_bus *bus)
> >  {
> > -	return NUMA_NO_NODE;
> > +	return acpi_disabled ? NUMA_NO_NODE : acpi_pci_bus_find_numa_node(bus);
> 
> I looked into how this works with devicetree.
> 
> With ACPI it is set directly in pci_register_host_bridge() with
> set_dev_node().
> 
> For the DT case the set_dev_node call sets it to NUMA_NO_NODE first.
> Since in DT the bridge is a platform device which has the node id
> assigned already (if there is one), the bus' node id is set later in
> device_add() when deriving it from the parent device which is the
> bridge. So this should work.

Which also means that the node propagation for bus->dev in patch 2 can
be probably removed :), the problem with ACPI is setting the node
for the host bridge which in DT is done by default at platform device
creation, the rest is done by the core already there is not any need
to propagate it again when child busses are created (they take their
node from the parent).

Thanks for the heads-up and testing,
Lorenzo

> I have tested it both DT and ACPI.
> 
> Thanks,
> 
> -Robert
> 
> >  }
> >  
> >  /**
diff mbox

Patch

diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index 0018603..915da79 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -10,6 +10,7 @@ 
 #include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/irqdomain.h>
+#include <linux/numa.h>
 #include <linux/pci.h>
 #include <linux/msi.h>
 #include <linux/pci_hotplug.h>
@@ -853,6 +854,25 @@  struct irq_domain *pci_host_bridge_acpi_msi_domain(struct pci_bus *bus)
 	return irq_find_matching_fwnode(fwnode, DOMAIN_BUS_PCI_MSI);
 }
 
+int acpi_pci_bus_find_numa_node(struct pci_bus *bus)
+{
+	int node = NUMA_NO_NODE;
+	struct device *bridge = get_device(bus->bridge);
+
+	if (!bridge)
+		return node;
+
+	if (has_acpi_companion(bridge)) {
+		struct acpi_device *adev = to_acpi_device_node(bridge->fwnode);
+
+		node = acpi_get_node(adev->handle);
+	}
+
+	put_device(bridge);
+
+	return node;
+}
+
 static int __init acpi_pci_init(void)
 {
 	int ret;
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index e9803c1..451342d 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -5406,7 +5406,7 @@  int pci_bus_find_domain_nr(struct pci_bus *bus, struct device *parent)
 
 int pci_bus_find_numa_node(struct pci_bus *bus)
 {
-	return NUMA_NO_NODE;
+	return acpi_disabled ? NUMA_NO_NODE : acpi_pci_bus_find_numa_node(bus);
 }
 
 /**
diff --git a/include/linux/pci.h b/include/linux/pci.h
index ccbeefd..ed89220 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1472,6 +1472,12 @@  static inline int acpi_pci_bus_find_domain_nr(struct pci_bus *bus)
 #endif
 int pci_bus_find_domain_nr(struct pci_bus *bus, struct device *parent);
 #endif
+#ifdef CONFIG_ACPI
+int acpi_pci_bus_find_numa_node(struct pci_bus *bus);
+#else
+static inline int acpi_pci_bus_find_numa_node(struct pci_bus *bus)
+{ return NUMA_NO_NODE; }
+#endif
 int pci_bus_find_numa_node(struct pci_bus *bus);
 
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