[PATCH] Fix build error in !CONFIG_SMP and CONFIG_ARM

[Minchan Kim]

Matt Sealey reported he fail to build zsmalloc due to use of
local_flush_tlb_kernel_range which are architecture dependent
function so !CONFIG_SMP in ARM couldn't implement it so it ends up
build error.

  MODPOST 216 modules
  LZMA    arch/arm/boot/compressed/piggy.lzma
  AS      arch/arm/boot/compressed/lib1funcs.o
ERROR: "v7wbi_flush_kern_tlb_range"
[drivers/staging/zsmalloc/zsmalloc.ko] undefined!
make[1]: *** [__modpost] Error 1
make: *** [modules] Error 2
make: *** Waiting for unfinished jobs....

The reason we used that function is copy method by [1]
was really slow in ARM but at that time, we didn't check
local_flush_tlb_kernel_range and flush_tlb_kernel_range's
performance gap.

Today, my experiment in ARMv7 processor 4 core didn't make
any difference with zsmapbench[2] but still page-table based
is better than copy-based.

* bigger is better.

1. local_flush_tlb_kernel_range: 3918795 mappings
2. flush_tlb_kernel_range : 3989538 mappings
3. copy-based: 635158 mappings

This patch replace local_flush_tlb_kernel_range with
flush_tlb_kernel_range which are avaialbe in all architectures
because it is already used by vmalloc allocator which are generic one.
So build problem should go away and performane loss shoud be void.

[1] f553646, zsmalloc: add page table mapping method
[2] https://github.com/spartacus06/zsmapbench

Reported-by: Matt Sealey <matt@xxxxxxxxxxxxxx>
Signed-off-by: Minchan Kim <minchan@xxxxxxxxxx>
---
 drivers/staging/zsmalloc/zsmalloc-main.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/zsmalloc/zsmalloc-main.c b/drivers/staging/zsmalloc/zsmalloc-main.c
index eb00772..66aa4df 100644
--- a/drivers/staging/zsmalloc/zsmalloc-main.c
+++ b/drivers/staging/zsmalloc/zsmalloc-main.c
@@ -663,7 +663,7 @@ static inline void __zs_unmap_object(struct mapping_area *area,
 
 	flush_cache_vunmap(addr, end);
 	unmap_kernel_range_noflush(addr, PAGE_SIZE * 2);
-	local_flush_tlb_kernel_range(addr, end);
+	flush_tlb_kernel_range(addr, end);
 }
 
 #else /* USE_PGTABLE_MAPPING */
-- 
1.7.9.5


-- 
Kind regards,
Minchan Kim
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