Re: [PATCH v10 4/6] benchtests: Add benchtests for dl_elf_hash, dl_new_hash and nss_hash

[Siddhesh Poyarekar <siddhesh@gotplt.org>]

On 18/05/2022 22:56, Noah Goldstein via Libc-alpha wrote:
> Benchtests are for throughput and include random / fixed size
> benchmarks.
> ---
>   benchtests/Makefile                  |  25 ++++-
>   benchtests/README                    |   9 +-
>   benchtests/bench-dl-elf-hash.c       |  27 +++++
>   benchtests/bench-dl-new-hash.c       |  25 +++++
>   benchtests/bench-hash-funcs-kernel.h |  92 ++++++++++++++++
>   benchtests/bench-hash-funcs.c        | 152 +++++++++++++++++++++++++++
>   benchtests/bench-nss-hash.c          |  26 +++++
>   7 files changed, 348 insertions(+), 8 deletions(-)
>   create mode 100644 benchtests/bench-dl-elf-hash.c
>   create mode 100644 benchtests/bench-dl-new-hash.c
>   create mode 100644 benchtests/bench-hash-funcs-kernel.h
>   create mode 100644 benchtests/bench-hash-funcs.c
>   create mode 100644 benchtests/bench-nss-hash.c
> 
> diff --git a/benchtests/Makefile b/benchtests/Makefile
> index de9de5cf58..c279041e19 100644
> --- a/benchtests/Makefile
> +++ b/benchtests/Makefile
> @@ -227,6 +227,12 @@ LOCALES := \
>   include ../gen-locales.mk
>   endif
>   
> +hash-benchset := \
> +  dl-elf-hash \
> +  dl-new-hash \
> +  nss-hash \
> +# hash-benchset
> +
>   stdlib-benchset := strtod
>   
>   stdio-common-benchset := sprintf
> @@ -235,7 +241,7 @@ math-benchset := math-inlines
>   
>   ifeq (${BENCHSET},)
>   benchset := $(string-benchset-all) $(stdlib-benchset) $(stdio-common-benchset) \
> -	    $(math-benchset)
> +	    $(math-benchset) $(hash-benchset)
>   else
>   benchset := $(foreach B,$(filter %-benchset,${BENCHSET}), ${${B}})
>   endif
> @@ -363,9 +369,20 @@ bench-clean:
>   
>   # Validate the passed in BENCHSET
>   ifneq ($(strip ${BENCHSET}),)
> -VALIDBENCHSETNAMES := bench-pthread bench-math bench-string string-benchset \
> -   wcsmbs-benchset stdlib-benchset stdio-common-benchset math-benchset \
> -   malloc-thread malloc-simple
> +VALIDBENCHSETNAMES := \
> +  bench-math \
> +  bench-pthread \
> +  bench-string \
> +  hash-benchset \
> +  malloc-simple \
> +  malloc-thread \
> +  math-benchset \
> +  stdio-common-benchset \
> +  stdlib-benchset \
> +  string-benchset \
> +  wcsmbs-benchset \
> +# VALIDBENCHSETNAMES
> +
>   INVALIDBENCHSETNAMES := $(filter-out ${VALIDBENCHSETNAMES},${BENCHSET})
>   ifneq (${INVALIDBENCHSETNAMES},)
>   $(info The following values in BENCHSET are invalid: ${INVALIDBENCHSETNAMES})
> diff --git a/benchtests/README b/benchtests/README
> index 4d83a05b4b..998ba9b2b4 100644
> --- a/benchtests/README
> +++ b/benchtests/README
> @@ -84,12 +84,13 @@ where BENCHSET may be a space-separated list of the following values:
>       bench-math
>       bench-pthread
>       bench-string
> +    hash-benchset
> +    malloc-thread
> +    math-benchset
> +    stdio-common-benchset
> +    stdlib-benchset
>       string-benchset
>       wcsmbs-benchset
> -    stdlib-benchset
> -    stdio-common-benchset
> -    math-benchset
> -    malloc-thread
>   
>   Adding a function to benchtests:
>   ===============================
> diff --git a/benchtests/bench-dl-elf-hash.c b/benchtests/bench-dl-elf-hash.c
> new file mode 100644
> index 0000000000..067de9fca4
> --- /dev/null
> +++ b/benchtests/bench-dl-elf-hash.c
> @@ -0,0 +1,27 @@
> +/* Measure __dl_new_hash runtime
> +   Copyright (C) 2022 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library; if not, see
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#include <dl-hash.h>
> +#include <elf/simple-dl-hash.h>
> +#define TEST_FUNC(x, y) _dl_elf_hash (x)
> +#define SIMPLE_TEST_FUNC(x, y) __simple_dl_elf_hash (x)
> +
> +#define TEST_NAME "_dl_elf_hash"
> +
> +
> +#include "bench-hash-funcs.c"

OK.

> diff --git a/benchtests/bench-dl-new-hash.c b/benchtests/bench-dl-new-hash.c
> new file mode 100644
> index 0000000000..3c8a1d5a82
> --- /dev/null
> +++ b/benchtests/bench-dl-new-hash.c
> @@ -0,0 +1,25 @@
> +/* Measure __dl_new_hash runtime
> +   Copyright (C) 2022 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library; if not, see
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#include <elf/dl-new-hash.h>
> +#define TEST_FUNC(x, y) _dl_new_hash (x)
> +#define SIMPLE_TEST_FUNC(x, y) __simple_dl_new_hash (x)
> +
> +#define TEST_NAME "_dl_new_hash"
> +
> +#include "bench-hash-funcs.c"

OK.

> diff --git a/benchtests/bench-hash-funcs-kernel.h b/benchtests/bench-hash-funcs-kernel.h
> new file mode 100644
> index 0000000000..9f9f245641
> --- /dev/null
> +++ b/benchtests/bench-hash-funcs-kernel.h
> @@ -0,0 +1,92 @@
> +/* Actual benchmark kernels used by bench-hash-funcs.h
> +   Copyright (C) 2022 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library; if not, see
> +   <https://www.gnu.org/licenses/>.  */
> +
> +
> +
> +/* We go through the trouble of using macros here because many of the
> +   hash functions are meant to be inlined so its not fair to benchmark
> +   them with a function pointer where they won't be inlinable. */
> +#undef RUN_FUNC
> +#undef POSTFIX
> +#ifdef SIMPLE
> +# define RUN_FUNC SIMPLE_TEST_FUNC
> +# define POSTFIX _simple
> +#else
> +# define RUN_FUNC TEST_FUNC
> +# define POSTFIX _optimized
> +#endif
> +
> +#define PRIMITIVE_CAT(x, y) x ## y
> +#define CAT(x, y) PRIMITIVE_CAT (x, y)
> +
> +static double __attribute__ ((noinline, noclone))
> +CAT (do_one_test_kernel, POSTFIX) (const char *s, size_t len)
> +{
> +
> +  unsigned int iters;
> +  timing_t start, stop, cur;
> +
> +  /* Warmup.  */
> +  for (iters = NFIXED_ITERS / 32; iters; --iters)
> +    {

Redundant braces here and elsewhere below.

> +      DO_NOT_OPTIMIZE_OUT (RUN_FUNC (s, len));
> +    }
> +
> +  TIMING_NOW (start);
> +  for (iters = NFIXED_ITERS; iters; --iters)
> +    {
> +      DO_NOT_OPTIMIZE_OUT (RUN_FUNC (s, len));
> +    }
> +  TIMING_NOW (stop);
> +
> +  TIMING_DIFF (cur, start, stop);
> +
> +  (void) (len);
> +  return (double) cur / (double) NFIXED_ITERS;
> +}
> +
> +static double __attribute__ ((noinline, noclone))
> +CAT (do_rand_test_kernel, POSTFIX) (char const *bufs,
> +				    unsigned int const *sizes)
> +{
> +  unsigned int i, iters;
> +  size_t offset;
> +  timing_t start, stop, cur;
> +
> +  /* Warmup.  */
> +  for (i = 0, offset = 0; i < NRAND_BUFS; ++i, offset += RAND_BENCH_MAX_LEN)
> +    {
> +      DO_NOT_OPTIMIZE_OUT (RUN_FUNC (bufs + offset, sizes[i]));
> +    }
> +
> +  TIMING_NOW (start);
> +  for (iters = NRAND_ITERS; iters; --iters)
> +    {
> +      for (i = 0, offset = 0; i < NRAND_BUFS;
> +	   ++i, offset += RAND_BENCH_MAX_LEN)
> +	{
> +	  DO_NOT_OPTIMIZE_OUT (RUN_FUNC (bufs + offset, sizes[i]));
> +	}
> +    }
> +  TIMING_NOW (stop);
> +
> +  TIMING_DIFF (cur, start, stop);
> +
> +  (void) (sizes);
> +  return (double) cur / (double) (NRAND_ITERS * NRAND_BUFS);
> +}
> diff --git a/benchtests/bench-hash-funcs.c b/benchtests/bench-hash-funcs.c
> new file mode 100644
> index 0000000000..3d3c736ffc
> --- /dev/null
> +++ b/benchtests/bench-hash-funcs.c
> @@ -0,0 +1,152 @@
> +/* Measure hash functions runtime.
> +   Copyright (C) 2022 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library; if not, see
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#define TEST_MAIN
> +#ifndef TEST_FUNC
> +# error "No TEST_FUNC provided!"
> +#endif
> +#ifndef SIMPLE_TEST_FUNC
> +# error "No SIMPLE_TEST_FUNC provided!"
> +#endif
> +
> +#ifndef TEST_NAME
> +# define STRINGIFY_PRIMITIVE(x) #  x
> +# define STRINGIFY(x) STRINGIFY_PRIMITIVE (x)
> +
> +# define TEST_NAME STRINGIFY (TEST_FUNC)
> +#endif
> +
> +#include "json-lib.h"
> +#include "bench-timing.h"
> +
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +
> +#define DO_NOT_OPTIMIZE_OUT(x) __asm__ volatile("" : : "r,m"(x) : "memory")
> +
> +enum
> +{
> +  NFIXED_ITERS = 1048576,
> +  NRAND_BUFS = 16384,
> +  NRAND_ITERS = 2048,
> +  RAND_BENCH_MAX_LEN = 128
> +};
> +
> +#include "bench-hash-funcs-kernel.h"
> +#define SIMPLE
> +#include "bench-hash-funcs-kernel.h"
> +
> +static void
> +do_one_test (json_ctx_t *json_ctx, size_t len)
> +{
> +  char buf[len + 1];
> +  memset (buf, -1, len);
> +  buf[len] = '\0';
> +
> +  json_element_object_begin (json_ctx);
> +
> +  json_attr_string (json_ctx, "type", "fixed");
> +  json_attr_uint (json_ctx, "length", len);
> +  json_attr_double (json_ctx, "time_simple", do_one_test_kernel_simple (buf, len));
> +  json_attr_double (json_ctx, "time_optimized", do_one_test_kernel_optimized (buf, len));
> +
> +  json_element_object_end (json_ctx);
> +}
> +
> +static void __attribute__ ((noinline, noclone))
> +do_rand_test (json_ctx_t *json_ctx)
> +{
> +  size_t i, sz, offset;
> +  char *bufs;
> +  unsigned int *sizes;
> +
> +  bufs = (char *) calloc (NRAND_BUFS, RAND_BENCH_MAX_LEN);
> +  sizes = (unsigned int *) calloc (NRAND_BUFS, sizeof (unsigned int));
> +  if (bufs == NULL || sizes == NULL)
> +    {
> +      fprintf (stderr, "Failed to allocate bufs for random test\n");
> +      goto done;
> +    }
> +
> +  for (sz = 2; sz <= RAND_BENCH_MAX_LEN; sz += sz)
> +    {
> +      json_element_object_begin (json_ctx);
> +      json_attr_string (json_ctx, "type", "random");
> +      json_attr_uint (json_ctx, "length", sz);
> +
> +      for (i = 0, offset = 0; i < NRAND_BUFS;
> +	   ++i, offset += RAND_BENCH_MAX_LEN)
> +	{
> +	  sizes[i] = random () % sz;
> +	  memset (bufs + offset, -1, sizes[i]);
> +	  bufs[offset + sizes[i]] = '\0';
> +	}
> +
> +      json_attr_double (json_ctx, "time_simple",
> +			do_rand_test_kernel_simple (bufs, sizes));
> +      json_attr_double (json_ctx, "time_optimized",
> +			do_rand_test_kernel_optimized (bufs, sizes));
> +      json_element_object_end (json_ctx);
> +    }
> +
> +done:
> +  if (bufs)
> +    {

Redundant braces here and multiple places in this file.

> +      free (bufs);
> +    }
> +  if (sizes)
> +    {
> +      free (sizes);
> +    }
> +}
> +
> +static int
> +do_test (void)
> +{
> +  int i;
> +  json_ctx_t json_ctx;
> +
> +  json_init (&json_ctx, 0, stdout);
> +  json_document_begin (&json_ctx);
> +  json_attr_string (&json_ctx, "timing_type", TIMING_TYPE);
> +  json_attr_object_begin (&json_ctx, "functions");
> +  json_attr_object_begin (&json_ctx, TEST_NAME);
> +  json_array_begin (&json_ctx, "results");
> +
> +  for (i = 0; i < 16; ++i)
> +    {
> +      do_one_test (&json_ctx, i);
> +    }
> +
> +  for (i = 16; i <= 256; i += i)
> +    {
> +      do_one_test (&json_ctx, i);
> +    }
> +
> +  do_rand_test (&json_ctx);
> +
> +  json_array_end (&json_ctx);
> +  json_attr_object_end (&json_ctx);
> +  json_attr_object_end (&json_ctx);
> +  json_document_end (&json_ctx);
> +
> +  return 0;
> +}
> +
> +#include <support/test-driver.c>
> diff --git a/benchtests/bench-nss-hash.c b/benchtests/bench-nss-hash.c
> new file mode 100644
> index 0000000000..7e369428a2
> --- /dev/null
> +++ b/benchtests/bench-nss-hash.c
> @@ -0,0 +1,26 @@
> +/* Measure __nss_hash runtime
> +   Copyright (C) 2022 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library; if not, see
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#include <nss.h>
> +#include <nss/simple-nss-hash.h>
> +#define TEST_FUNC __nss_hash
> +#define SIMPLE_TEST_FUNC __simple_nss_hash
> +
> +uint32_t __nss_hash (const void *__key, size_t __length);
> +
> +#include "bench-hash-funcs.c"

OK.

So just the redundant braces to fix and you should be OK.  Please send 
V11 with the change.

Thanks,
Siddhesh