ladybird/Userland/allocate.cpp
Lenny Maiorani 765936ebae
Everywhere: Switch from (void) to [[maybe_unused]] (#4473)
Problem:
- `(void)` simply casts the expression to void. This is understood to
  indicate that it is ignored, but this is really a compiler trick to
  get the compiler to not generate a warning.

Solution:
- Use the `[[maybe_unused]]` attribute to indicate the value is unused.

Note:
- Functions taking a `(void)` argument list have also been changed to
  `()` because this is not needed and shows up in the same grep
  command.
2020-12-21 00:09:48 +01:00

130 lines
3.5 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <AK/Optional.h>
#include <AK/String.h>
#include <LibCore/ElapsedTimer.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
static void usage()
{
printf("usage: allocate [number [unit (B/KiB/MiB)]]\n");
exit(1);
}
enum class Unit {
Bytes,
KiB,
MiB,
};
int main(int argc, char** argv)
{
int count = 50;
auto unit = Unit::MiB;
if (argc >= 2) {
auto number = String(argv[1]).to_uint();
if (!number.has_value()) {
usage();
}
count = number.value();
}
if (argc >= 3) {
if (strcmp(argv[2], "B") == 0)
unit = Unit::Bytes;
else if (strcmp(argv[2], "KiB") == 0)
unit = Unit::KiB;
else if (strcmp(argv[2], "MiB") == 0)
unit = Unit::MiB;
else
usage();
}
switch (unit) {
case Unit::Bytes:
break;
case Unit::KiB:
count *= KiB;
break;
case Unit::MiB:
count *= MiB;
break;
}
Core::ElapsedTimer timer;
printf("allocating memory (%d bytes)...\n", count);
timer.start();
char* ptr = (char*)malloc(count);
if (!ptr) {
printf("failed.\n");
return 1;
}
printf("done in %dms\n", timer.elapsed());
auto pages = count / PAGE_SIZE;
auto step = pages / 10;
Core::ElapsedTimer timer2;
printf("writing one byte to each page of allocated memory...\n");
timer.start();
timer2.start();
for (int i = 0; i < pages; ++i) {
ptr[i * PAGE_SIZE] = 1;
if (i != 0 && (i % step) == 0) {
auto ms = timer2.elapsed();
if (ms == 0)
ms = 1;
auto bps = double(step * PAGE_SIZE) / (double(ms) / 1000);
printf("step took %dms (%fMiB/s)\n", ms, bps / MiB);
timer2.start();
}
}
printf("done in %dms\n", timer.elapsed());
printf("sleeping for ten seconds...\n");
for (int i = 0; i < 10; i++) {
printf("%d\n", i);
sleep(1);
}
printf("done.\n");
printf("freeing memory...\n");
timer.start();
free(ptr);
printf("done in %dms\n", timer.elapsed());
return 0;
}