Re: [PATCH] arm64, pci, numa: Adding helper functions as required by pci

From: Ganapatrao Kulkarni
Date: Sat Jan 09 2016 - 01:06:06 EST


On Fri, Jan 8, 2016 at 11:36 PM, Will Deacon <will.deacon@xxxxxxx> wrote:
> On Fri, Jan 08, 2016 at 12:01:31PM -0600, Bjorn Helgaas wrote:
>> On Tue, Dec 22, 2015 at 04:08:50PM +0530, Ganapatrao Kulkarni wrote:
>> > Adding helper functions and necessary code to make
>> > pci driver(pci-host-generic) numa aware.
>> >
>> > This patch is on top of arm64-numa v7.
>> > http://www.spinics.net/lists/arm-kernel/msg460813.html
>> >
>> > Signed-off-by: Ganapatrao Kulkarni <gkulkarni@xxxxxxxxxxxxxxxxxx>
>> > ---
>> > arch/arm64/include/asm/numa.h | 8 +++++---
>> > arch/arm64/kernel/pci.c | 8 ++++++++
>> > drivers/pci/host/pci-host-generic.c | 1 +
>> > 3 files changed, 14 insertions(+), 3 deletions(-)
>> >
>> > diff --git a/arch/arm64/include/asm/numa.h b/arch/arm64/include/asm/numa.h
>> > index b8c2a3f..1eca4db 100644
>> > --- a/arch/arm64/include/asm/numa.h
>> > +++ b/arch/arm64/include/asm/numa.h
>> > @@ -15,9 +15,11 @@
>> > extern int __node_distance(int from, int to);
>> > #define node_distance(a, b) __node_distance(a, b)
>> >
>> > -/* dummy definitions for pci functions */
>> > -#define pcibus_to_node(node) 0
>> > -#define cpumask_of_pcibus(bus) 0
>> > +struct pci_bus;
>> > +extern int pcibus_to_node(struct pci_bus *bus);
>> > +#define cpumask_of_pcibus(bus) (pcibus_to_node(bus) == -1 ? \
>> > + cpu_all_mask : \
>> > + cpumask_of_node(pcibus_to_node(bus)))
>>
>> All the arch definitions of cpumask_of_pcibus() are pretty similar;
>> could they be made more generic? At the very least, can you drop the
>> definition here and use the one in include/asm-generic/topology.h,
>> which is identical to what you're defining here?
macro cpumask_of_pcibus is defined under #ifndef CONFIG_NUMA in
include/asm-generic/topology.h
and this macro is defined again for NUMA in respective arch header files.
i think moving this macro from ifndef will allow us to use without redefinition.

--- a/include/asm-generic/topology.h
+++ b/include/asm-generic/topology.h
@@ -54,14 +54,14 @@
#define pcibus_to_node(bus) ((void)(bus), -1)
#endif

+#endif /* CONFIG_NUMA */
+
#ifndef cpumask_of_pcibus
#define cpumask_of_pcibus(bus) (pcibus_to_node(bus) == -1 ? \
cpu_all_mask : \
cpumask_of_node(pcibus_to_node(bus)))
#endif

-#endif /* CONFIG_NUMA */
-
#if !defined(CONFIG_NUMA) || !defined(CONFIG_HAVE_MEMORYLESS_NODES)

#ifndef set_numa_mem

i have got below compilation error withour macro defined in arch code.

drivers/pci/pci-sysfs.c: In function âcpuaffinity_showâ:
drivers/pci/pci-sysfs.c:114:15: error: implicit declaration of
function âcpumask_of_pcibusâ [-Werror=implicit-function-declaration]
drivers/pci/pci-sysfs.c:114:34: warning: initialization makes pointer
from integer without a cast [enabled by default]
drivers/pci/pci-sysfs.c: In function âcpulistaffinity_showâ:
drivers/pci/pci-sysfs.c:123:34: warning: initialization makes pointer
from integer without a cast [enabled by default]
cc1: some warnings being treated as errors


i can send this as separate patch( as a fix patch).

>
> +1 on that. I asked for exactly the same thing in my review of v7:
>
> http://www.spinics.net/lists/arm-kernel/msg469592.html
>
> but it looks like I was just ignored.
>
> Will
thanks
ganapat