1 /* Measure memset function throughput with large data sizes.
2    Copyright (C) 2017-2022 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    <https://www.gnu.org/licenses/>.  */
18 
19 #define TEST_MAIN
20 #ifdef DO_MEMSET
21 # define TEST_NAME "memset"
22 #else
23 # define TEST_NAME "bzero"
24 #endif
25 #define START_SIZE 128
26 #define MIN_PAGE_SIZE (getpagesize () + 32 * 1024 * 1024)
27 #define TIMEOUT (20 * 60)
28 #include "bench-string.h"
29 
30 #include "json-lib.h"
31 
32 #ifdef DO_MEMSET
33 void *generic_memset (void *, int, size_t);
34 
35 typedef void *(*proto_t) (void *, int, size_t);
36 
37 IMPL (memset, 1)
38 IMPL (generic_memset, 0)
39 
40 #else
41 static void
42 memset_zero (void * s, size_t len)
43 {
44   memset (s, '\0', len);
45 }
46 
47 typedef void (*proto_t) (void *, size_t);
48 
49 IMPL (bzero, 1)
50 IMPL (memset_zero, 0)
51 #endif
52 
53 static void
do_one_test(json_ctx_t * json_ctx,impl_t * impl,CHAR * s,CHAR * s_end,size_t n)54 do_one_test (json_ctx_t *json_ctx, impl_t *impl, CHAR *s, CHAR *s_end,
55 	     size_t n)
56 {
57   size_t i, iters = MIN_PAGE_SIZE / n;
58   timing_t start, stop, cur;
59 
60   TIMING_NOW (start);
61   for (i = 0; i < iters && s <= s_end; s_end -= n, i++)
62 #ifdef DO_MEMSET
63     CALL (impl, s, 0, n);
64 #else
65     CALL (impl, s, n);
66 #endif
67   TIMING_NOW (stop);
68 
69   TIMING_DIFF (cur, start, stop);
70 
71   /* Get time taken per function call.  */
72   json_element_double (json_ctx, (double) cur / i);
73 }
74 
75 static void
do_test(json_ctx_t * json_ctx,size_t len)76 do_test (json_ctx_t *json_ctx, size_t len)
77 {
78   json_element_object_begin (json_ctx);
79   json_attr_uint (json_ctx, "length", len);
80   json_array_begin (json_ctx, "timings");
81 
82   FOR_EACH_IMPL (impl, 0)
83     {
84       do_one_test (json_ctx, impl, (CHAR *) buf1,
85 		   (CHAR *) buf1 + MIN_PAGE_SIZE - len, len);
86       alloc_bufs ();
87     }
88 
89   json_array_end (json_ctx);
90   json_element_object_end (json_ctx);
91 }
92 
93 int
test_main(void)94 test_main (void)
95 {
96   json_ctx_t json_ctx;
97   size_t i;
98 
99   test_init ();
100 
101   json_init (&json_ctx, 0, stdout);
102 
103   json_document_begin (&json_ctx);
104   json_attr_string (&json_ctx, "timing_type", TIMING_TYPE);
105 
106   json_attr_object_begin (&json_ctx, "functions");
107   json_attr_object_begin (&json_ctx, TEST_NAME);
108   json_attr_string (&json_ctx, "bench-variant", "walk");
109 
110   json_array_begin (&json_ctx, "ifuncs");
111   FOR_EACH_IMPL (impl, 0)
112     json_element_string (&json_ctx, impl->name);
113   json_array_end (&json_ctx);
114 
115   json_array_begin (&json_ctx, "results");
116   for (i = 1; i <= 64; i++)
117     do_test (&json_ctx, i);
118 
119   for (i = START_SIZE; i <= MIN_PAGE_SIZE; i <<= 1)
120     {
121       do_test (&json_ctx, i);
122       do_test (&json_ctx, i + 1);
123     }
124 
125   json_array_end (&json_ctx);
126   json_attr_object_end (&json_ctx);
127   json_attr_object_end (&json_ctx);
128   json_document_end (&json_ctx);
129 
130   return ret;
131 }
132 
133 #include <support/test-driver.c>
134 
135 #ifdef DO_MEMSET
136 # define libc_hidden_builtin_def(X)
137 # define libc_hidden_def(X)
138 # define libc_hidden_weak(X)
139 # define weak_alias(X,Y)
140 # undef MEMSET
141 # define MEMSET generic_memset
142 # include <string/memset.c>
143 #endif
144