benchtests/bench-memset-walk.c

   1 /* Measure memset function throughput with large data sizes.
   2    Copyright (C) 2017-2019 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #define TEST_MAIN
  20 #define TEST_NAME "memset"
  21 #define START_SIZE 128
  22 #define MIN_PAGE_SIZE (getpagesize () + 32 * 1024 * 1024)
  23 #define TIMEOUT (20 * 60)
  24 #include "bench-string.h"
  25
  26 #include <assert.h>
  27 #include "json-lib.h"
  28
  29 void *generic_memset (void *, int, size_t);
  30 typedef void *(*proto_t) (void *, int, size_t);
  31
  32 IMPL (MEMSET, 1)
  33 IMPL (generic_memset, 0)
  34
  35 static void
  36 do_one_test (json_ctx_t *json_ctx, impl_t *impl, CHAR *s, CHAR *s_end,
  37              int c __attribute ((unused)), size_t n)
  38 {
  39   size_t i, iters = MIN_PAGE_SIZE / n;
  40   timing_t start, stop, cur;
  41
  42   TIMING_NOW (start);
  43   for (i = 0; i < iters && s <= s_end; s_end -= n, i++)
  44     CALL (impl, s, c, n);
  45   TIMING_NOW (stop);
  46
  47   TIMING_DIFF (cur, start, stop);
  48
  49   /* Get time taken per function call.  */
  50   json_element_double (json_ctx, (double) cur / i);
  51 }
  52
  53 static void
  54 do_test (json_ctx_t *json_ctx, int c, size_t len)
  55 {
  56   json_element_object_begin (json_ctx);
  57   json_attr_uint (json_ctx, "length", len);
  58   json_attr_uint (json_ctx, "char", c);
  59   json_array_begin (json_ctx, "timings");
  60
  61   FOR_EACH_IMPL (impl, 0)
  62     {
  63       do_one_test (json_ctx, impl, (CHAR *) buf1,
  64                    (CHAR *) buf1 + MIN_PAGE_SIZE - len, c, len);
  65       alloc_bufs ();
  66     }
  67
  68   json_array_end (json_ctx);
  69   json_element_object_end (json_ctx);
  70 }
  71
  72 int
  73 test_main (void)
  74 {
  75   json_ctx_t json_ctx;
  76   size_t i;
  77
  78   test_init ();
  79
  80   json_init (&json_ctx, 0, stdout);
  81
  82   json_document_begin (&json_ctx);
  83   json_attr_string (&json_ctx, "timing_type", TIMING_TYPE);
  84
  85   json_attr_object_begin (&json_ctx, "functions");
  86   json_attr_object_begin (&json_ctx, TEST_NAME);
  87   json_attr_string (&json_ctx, "bench-variant", "walk");
  88
  89   json_array_begin (&json_ctx, "ifuncs");
  90   FOR_EACH_IMPL (impl, 0)
  91     json_element_string (&json_ctx, impl->name);
  92   json_array_end (&json_ctx);
  93
  94   json_array_begin (&json_ctx, "results");
  95   for (i = START_SIZE; i <= MIN_PAGE_SIZE; i <<= 1)
  96     {
  97       do_test (&json_ctx, 65, i);
  98       do_test (&json_ctx, 65, i + 1);
  99     }
 100
 101   for (i = START_SIZE; i <= MIN_PAGE_SIZE; i <<= 1)
 102     {
 103       do_test (&json_ctx, 0, i);
 104       do_test (&json_ctx, 0, i + 1);
 105     }
 106
 107   json_array_end (&json_ctx);
 108   json_attr_object_end (&json_ctx);
 109   json_attr_object_end (&json_ctx);
 110   json_document_end (&json_ctx);
 111
 112   return ret;
 113 }
 114
 115 #include <support/test-driver.c>
 116
 117 #define libc_hidden_builtin_def(X)
 118 #define libc_hidden_def(X)
 119 #define libc_hidden_weak(X)
 120 #define weak_alias(X,Y)
 121 #undef MEMSET
 122 #define MEMSET generic_memset
 123 #include <string/memset.c>