This was causing the destination instead of the source to be filled.
As a result, the source was typically all mapped to one zero page,
and hence very cacheable
---
tools/perf/bench/mem-memcpy.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/tools/perf/bench/mem-memcpy.c b/tools/perf/bench/mem-memcpy.c
index 6c14afe..db1d3a2 100644
--- a/tools/perf/bench/mem-memcpy.c
+++ b/tools/perf/bench/mem-memcpy.c
@@ -289,7 +289,7 @@ static u64 do_memcpy_cycle(const struct routine
*r, size_t len, bool prefault)
memcpy_t fn = r->fn.memcpy;
int i;
- memcpy_alloc_mem(&src, &dst, len);
+ memcpy_alloc_mem(&dst, &src, len);
if (prefault)
fn(dst, src, len);
@@ -312,7 +312,7 @@ static double do_memcpy_gettimeofday(const struct
routine *r, size_t len,
void *src = NULL, *dst = NULL;
int i;
- memcpy_alloc_mem(&src, &dst, len);
+ memcpy_alloc_mem(&dst, &src, len);
if (prefault)
fn(dst, src, len);
--
1.9.1
--
Bruce Merry
Senior Science Processing Developer
SKA South Africa
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