[PATCH] powerpc/powernv: Fix memtrace build when NUMA=n

[PATCH] powerpc/powernv: Fix memtrace build when NUMA=n

[Michael Ellerman]

Currently memtrace doesn't build if NUMA=n:

  In function ‘memtrace_alloc_node’:
  arch/powerpc/platforms/powernv/memtrace.c:134:6:
  error: the address of ‘contig_page_data’ will always evaluate as ‘true’
    if (!NODE_DATA(nid) || !node_spanned_pages(nid))
        ^

This is because for NUMA=n NODE_DATA(nid) points to an always
allocated structure, contig_page_data.

But even in the NUMA=y case memtrace_alloc_node() is only called for
online nodes, and we should always have a NODE_DATA() allocated for an
online node. So remove the (hopefully) overly paranoid check, which
also means we can build when NUMA=n.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/platforms/powernv/memtrace.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/powernv/memtrace.c b/arch/powerpc/platforms/powernv/memtrace.c
index fc222a0c2ac4..b99283df8584 100644
--- a/arch/powerpc/platforms/powernv/memtrace.c
+++ b/arch/powerpc/platforms/powernv/memtrace.c
@@ -131,7 +131,7 @@ static u64 memtrace_alloc_node(u32 nid, u64 size)
 	u64 start_pfn, end_pfn, nr_pages;
 	u64 base_pfn;
 
-	if (!NODE_DATA(nid) || !node_spanned_pages(nid))
+	if (!node_spanned_pages(nid))
 		return 0;
 
 	start_pfn = node_start_pfn(nid);
-- 
2.14.1

Re: powerpc/powernv: Fix memtrace build when NUMA=n

[Michael Ellerman]

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On Thu, 2018-05-10 at 13:09:13 UTC, Michael Ellerman wrote:
> Currently memtrace doesn't build if NUMA=n:
> 
>   In function ‘memtrace_alloc_node’:
>   arch/powerpc/platforms/powernv/memtrace.c:134:6:
>   error: the address of ‘contig_page_data’ will always evaluate as ‘true’
>     if (!NODE_DATA(nid) || !node_spanned_pages(nid))
>         ^
> 
> This is because for NUMA=n NODE_DATA(nid) points to an always
> allocated structure, contig_page_data.
> 
> But even in the NUMA=y case memtrace_alloc_node() is only called for
> online nodes, and we should always have a NODE_DATA() allocated for an
> online node. So remove the (hopefully) overly paranoid check, which
> also means we can build when NUMA=n.
> 
> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Applied to powerpc next.

https://git.kernel.org/powerpc/c/8ccb442dec0ab53eefb5a607e405f7

cheers