[v2,1/2] Bench: Add support for choose direction of memcpy in benchtests

  This patch adds support for testing memcpy with both dst > src and dst
< src. Since memcpy is implemented as memmove which has seperate
control flows for certain sizes depending on dst > src it seems like
1) information that should be provided in the benchtest output and a
variable that can be controlled for the benchmarks.

Signed-off-by: Noah Goldstein <goldstein.w.n@gmail.com>
---
 benchtests/bench-memcpy-large.c | 50 +++++++++++++---------
 benchtests/bench-memcpy-walk.c  | 33 +++++++++-----
 benchtests/bench-memcpy.c       | 76 ++++++++++++++++++---------------
 3 files changed, 94 insertions(+), 65 deletions(-)
  

On Sun, May 23, 2021 at 8:15 PM Noah Goldstein <goldstein.w.n@gmail.com> wrote:
>
> This patch adds support for testing memcpy with both dst > src and dst
> < src. Since memcpy is implemented as memmove which has seperate
> control flows for certain sizes depending on dst > src it seems like
> 1) information that should be provided in the benchtest output and a
> variable that can be controlled for the benchmarks.
>
> Signed-off-by: Noah Goldstein <goldstein.w.n@gmail.com>
> ---
>  benchtests/bench-memcpy-large.c | 50 +++++++++++++---------
>  benchtests/bench-memcpy-walk.c  | 33 +++++++++-----
>  benchtests/bench-memcpy.c       | 76 ++++++++++++++++++---------------
>  3 files changed, 94 insertions(+), 65 deletions(-)
>
> diff --git a/benchtests/bench-memcpy-large.c b/benchtests/bench-memcpy-large.c
> index efb9627b1e..0021274e92 100644
> --- a/benchtests/bench-memcpy-large.c
> +++ b/benchtests/bench-memcpy-large.c
> @@ -52,11 +52,12 @@ do_one_test (json_ctx_t *json_ctx, impl_t *impl, char *dst, const char *src,
>  }
>
>  static void
> -do_test (json_ctx_t *json_ctx, size_t align1, size_t align2, size_t len)
> +do_test (json_ctx_t *json_ctx, size_t align1, size_t align2, size_t len,
> +         int both_ways)
>  {
>    size_t i, j;
>    char *s1, *s2;
> -
> +  size_t repeats;
>    align1 &= 4095;
>    if (align1 + len >= page_size)
>      return;
> @@ -68,20 +69,27 @@ do_test (json_ctx_t *json_ctx, size_t align1, size_t align2, size_t len)
>    s1 = (char *) (buf1 + align1);
>    s2 = (char *) (buf2 + align2);
>
> -  for (i = 0, j = 1; i < len; i++, j += 23)
> -    s1[i] = j;
> +  for (repeats = both_ways ? 2 : 1; repeats; --repeats)
> +    {
> +      for (i = 0, j = 1; i < len; i++, j += 23)
> +        s1[i] = j;
>
> -  json_element_object_begin (json_ctx);
> -  json_attr_uint (json_ctx, "length", (double) len);
> -  json_attr_uint (json_ctx, "align1", (double) align1);
> -  json_attr_uint (json_ctx, "align2", (double) align2);
> -  json_array_begin (json_ctx, "timings");
> +      json_element_object_begin (json_ctx);
> +      json_attr_uint (json_ctx, "length", (double) len);
> +      json_attr_uint (json_ctx, "align1", (double) align1);
> +      json_attr_uint (json_ctx, "align2", (double) align2);
> +      json_attr_uint (json_ctx, "dst > src", (double) (s2 > s1));
> +      json_array_begin (json_ctx, "timings");
>
> -  FOR_EACH_IMPL (impl, 0)
> -    do_one_test (json_ctx, impl, s2, s1, len);
> +      FOR_EACH_IMPL (impl, 0)
> +        do_one_test (json_ctx, impl, s2, s1, len);
>
> -  json_array_end (json_ctx);
> -  json_element_object_end (json_ctx);
> +      json_array_end (json_ctx);
> +      json_element_object_end (json_ctx);
> +
> +      s1 = (char *) (buf2 + align1);
> +      s2 = (char *) (buf1 + align2);
> +    }
>  }
>
>  int
> @@ -109,14 +117,14 @@ test_main (void)
>    json_array_begin (&json_ctx, "results");
>    for (i = START_SIZE; i <= MIN_PAGE_SIZE; i <<= 1)
>      {
> -      do_test (&json_ctx, 0, 0, i + 7);
> -      do_test (&json_ctx, 0, 3, i + 15);
> -      do_test (&json_ctx, 3, 0, i + 31);
> -      do_test (&json_ctx, 3, 5, i + 63);
> -      do_test (&json_ctx, 0, 127, i);
> -      do_test (&json_ctx, 0, 255, i);
> -      do_test (&json_ctx, 0, 256, i);
> -      do_test (&json_ctx, 0, 4064, i);
> +      do_test (&json_ctx, 0, 0, i + 7, 1);
> +      do_test (&json_ctx, 0, 3, i + 15, 1);
> +      do_test (&json_ctx, 3, 0, i + 31, 1);
> +      do_test (&json_ctx, 3, 5, i + 63, 1);
> +      do_test (&json_ctx, 0, 127, i, 1);
> +      do_test (&json_ctx, 0, 255, i, 1);
> +      do_test (&json_ctx, 0, 256, i, 1);
> +      do_test (&json_ctx, 0, 4064, i, 1);
>      }
>
>    json_array_end (&json_ctx);
> diff --git a/benchtests/bench-memcpy-walk.c b/benchtests/bench-memcpy-walk.c
> index b04d8ac0ed..610529ef1b 100644
> --- a/benchtests/bench-memcpy-walk.c
> +++ b/benchtests/bench-memcpy-walk.c
> @@ -66,17 +66,30 @@ do_one_test (json_ctx_t *json_ctx, impl_t *impl, char *dst, char *src,
>  }
>
>  static void
> -do_test (json_ctx_t *json_ctx, size_t len)
> +do_test (json_ctx_t *json_ctx, size_t len, int both_ways)
>  {
> -  json_element_object_begin (json_ctx);
> -  json_attr_uint (json_ctx, "length", (double) len);
> -  json_array_begin (json_ctx, "timings");
>
> -  FOR_EACH_IMPL (impl, 0)
> -    do_one_test (json_ctx, impl, (char *) buf2, (char *) buf1, len);
> +  char *s1, *s2;
> +  size_t repeats;
> +  s1 = (char *) (buf1);
> +  s2 = (char *) (buf2);
> +
> +  for (repeats = both_ways ? 2 : 1; repeats; --repeats)
> +    {
> +      json_element_object_begin (json_ctx);
> +      json_attr_uint (json_ctx, "length", (double) len);
> +      json_attr_uint (json_ctx, "dst > src", (double) (s2 > s1));
> +      json_array_begin (json_ctx, "timings");
>
> -  json_array_end (json_ctx);
> -  json_element_object_end (json_ctx);
> +      FOR_EACH_IMPL (impl, 0)
> +        do_one_test (json_ctx, impl, s2, s1, len);
> +
> +      json_array_end (json_ctx);
> +      json_element_object_end (json_ctx);
> +
> +      s1 = (char *) (buf2);
> +      s2 = (char *) (buf1);
> +    }
>  }
>
>  int
> @@ -103,8 +116,8 @@ test_main (void)
>    json_array_begin (&json_ctx, "results");
>    for (size_t i = START_SIZE; i <= MIN_PAGE_SIZE; i <<= 1)
>      {
> -      do_test (&json_ctx, i);
> -      do_test (&json_ctx, i + 1);
> +      do_test (&json_ctx, i, 1);
> +      do_test (&json_ctx, i + 1, 1);
>      }
>
>    json_array_end (&json_ctx);
> diff --git a/benchtests/bench-memcpy.c b/benchtests/bench-memcpy.c
> index 184495d539..d9236a2282 100644
> --- a/benchtests/bench-memcpy.c
> +++ b/benchtests/bench-memcpy.c
> @@ -54,11 +54,12 @@ do_one_test (json_ctx_t *json_ctx, impl_t *impl, char *dst, const char *src,
>  }
>
>  static void
> -do_test (json_ctx_t *json_ctx, size_t align1, size_t align2, size_t len)
> +do_test (json_ctx_t *json_ctx, size_t align1, size_t align2, size_t len,
> +         int both_ways)
>  {
>    size_t i, j;
>    char *s1, *s2;
> -
> +  size_t repeats;
>    align1 &= 63;
>    if (align1 + len >= page_size)
>      return;
> @@ -70,20 +71,27 @@ do_test (json_ctx_t *json_ctx, size_t align1, size_t align2, size_t len)
>    s1 = (char *) (buf1 + align1);
>    s2 = (char *) (buf2 + align2);
>
> -  for (i = 0, j = 1; i < len; i++, j += 23)
> -    s1[i] = j;
> +  for (repeats = both_ways ? 2 : 1; repeats; --repeats)
> +    {
> +      for (i = 0, j = 1; i < len; i++, j += 23)
> +        s1[i] = j;
>
> -  json_element_object_begin (json_ctx);
> -  json_attr_uint (json_ctx, "length", (double) len);
> -  json_attr_uint (json_ctx, "align1", (double) align1);
> -  json_attr_uint (json_ctx, "align2", (double) align2);
> -  json_array_begin (json_ctx, "timings");
> +      json_element_object_begin (json_ctx);
> +      json_attr_uint (json_ctx, "length", (double) len);
> +      json_attr_uint (json_ctx, "align1", (double) align1);
> +      json_attr_uint (json_ctx, "align2", (double) align2);
> +      json_attr_uint (json_ctx, "dst > src", (double) (s2 > s1));
> +      json_array_begin (json_ctx, "timings");
>
> -  FOR_EACH_IMPL (impl, 0)
> -    do_one_test (json_ctx, impl, s2, s1, len);
> +      FOR_EACH_IMPL (impl, 0)
> +        do_one_test (json_ctx, impl, s2, s1, len);
>
> -  json_array_end (json_ctx);
> -  json_element_object_end (json_ctx);
> +      json_array_end (json_ctx);
> +      json_element_object_end (json_ctx);
> +
> +      s1 = (char *) (buf2 + align1);
> +      s2 = (char *) (buf1 + align2);
> +    }
>  }
>
>  int
> @@ -111,46 +119,46 @@ test_main (void)
>    json_array_begin (&json_ctx, "results");
>    for (i = 0; i < 18; ++i)
>      {
> -      do_test (&json_ctx, 0, 0, 1 << i);
> -      do_test (&json_ctx, i, 0, 1 << i);
> -      do_test (&json_ctx, 0, i, 1 << i);
> -      do_test (&json_ctx, i, i, 1 << i);
> +      do_test (&json_ctx, 0, 0, 1 << i, 1);
> +      do_test (&json_ctx, i, 0, 1 << i, 1);
> +      do_test (&json_ctx, 0, i, 1 << i, 1);
> +      do_test (&json_ctx, i, i, 1 << i, 1);
>      }
>
>    for (i = 0; i < 32; ++i)
>      {
> -      do_test (&json_ctx, 0, 0, i);
> -      do_test (&json_ctx, i, 0, i);
> -      do_test (&json_ctx, 0, i, i);
> -      do_test (&json_ctx, i, i, i);
> +      do_test (&json_ctx, 0, 0, i, 0);
> +      do_test (&json_ctx, i, 0, i, 0);
> +      do_test (&json_ctx, 0, i, i, 0);
> +      do_test (&json_ctx, i, i, i, 0);
>      }
>
>    for (i = 3; i < 32; ++i)
>      {
>        if ((i & (i - 1)) == 0)
>         continue;
> -      do_test (&json_ctx, 0, 0, 16 * i);
> -      do_test (&json_ctx, i, 0, 16 * i);
> -      do_test (&json_ctx, 0, i, 16 * i);
> -      do_test (&json_ctx, i, i, 16 * i);
> +      do_test (&json_ctx, 0, 0, 16 * i, 1);
> +      do_test (&json_ctx, i, 0, 16 * i, 1);
> +      do_test (&json_ctx, 0, i, 16 * i, 1);
> +      do_test (&json_ctx, i, i, 16 * i, 1);
>      }
>
>    for (i = 32; i < 64; ++i)
>      {
> -      do_test (&json_ctx, 0, 0, 32 * i);
> -      do_test (&json_ctx, i, 0, 32 * i);
> -      do_test (&json_ctx, 0, i, 32 * i);
> -      do_test (&json_ctx, i, i, 32 * i);
> +      do_test (&json_ctx, 0, 0, 32 * i, 1);
> +      do_test (&json_ctx, i, 0, 32 * i, 1);
> +      do_test (&json_ctx, 0, i, 32 * i, 1);
> +      do_test (&json_ctx, i, i, 32 * i, 1);
>      }
>
> -  do_test (&json_ctx, 0, 0, getpagesize ());
> +  do_test (&json_ctx, 0, 0, getpagesize (), 1);
>
>    for (i = 0; i <= 32; ++i)
>      {
> -      do_test (&json_ctx, 0, 0, 2048 + 64 * i);
> -      do_test (&json_ctx, i, 0, 2048 + 64 * i);
> -      do_test (&json_ctx, 0, i, 2048 + 64 * i);
> -      do_test (&json_ctx, i, i, 2048 + 64 * i);
> +      do_test (&json_ctx, 0, 0, 2048 + 64 * i, 1);
> +      do_test (&json_ctx, i, 0, 2048 + 64 * i, 1);
> +      do_test (&json_ctx, 0, i, 2048 + 64 * i, 1);
> +      do_test (&json_ctx, i, i, 2048 + 64 * i, 1);
>      }
>
>    json_array_end (&json_ctx);
> --
> 2.25.1
>

LGTM.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

Thanks.