mirror of
git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs.git
synced 2026-10-29 13:23:23 +01:00
Namhyung Kim
39281709a6
The sqrtloop creates a child process to run an infinite loop calling sqrt() with rand(). This is needed for ARM SPE fork test. $ perf test -w sqrtloop It can take an optional argument to specify how long it will run in seconds (default: 1). Committer notes: Explicitely ignored the sqrt() return to fix the build on systems where the compiler complains it isn't being used. And added a sqrtloop specific CFLAGS to disable optimizations to make this a bit more robust wrt dead code elimination. Doing that a -U_FORTIFY_SOURCE needs to be added, as -O0 is incompatible with it. Signed-off-by: Namhyung Kim <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Athira Jajeev <[email protected]> Cc: German Gomez <[email protected]> Cc: Ian Rogers <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: James Clark <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Leo Yan <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Zhengjun Xing <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
46 lines
667 B
C
46 lines
667 B
C
/* SPDX-License-Identifier: GPL-2.0 */
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#include <math.h>
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#include <signal.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include <linux/compiler.h>
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#include <sys/wait.h>
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#include "../tests.h"
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static volatile sig_atomic_t done;
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static void sighandler(int sig __maybe_unused)
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{
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done = 1;
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}
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static int __sqrtloop(int sec)
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{
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signal(SIGALRM, sighandler);
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alarm(sec);
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while (!done)
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(void)sqrt(rand());
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return 0;
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}
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static int sqrtloop(int argc, const char **argv)
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{
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int sec = 1;
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if (argc > 0)
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sec = atoi(argv[0]);
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switch (fork()) {
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case 0:
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return __sqrtloop(sec);
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case -1:
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return -1;
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default:
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wait(NULL);
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}
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return 0;
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}
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DEFINE_WORKLOAD(sqrtloop);
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