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/* SPDX-License-Identifier: GPL-2.0 */
#include <signal.h>
#include <stdlib.h>
#include <linux/compiler.h>
#include <unistd.h>
#include "../tests.h"
/* We want to check these symbols in perf script */
noinline void leaf(void);
noinline void parent(void);
static volatile sig_atomic_t done asm("leafloop_done");
static void sighandler(int sig __maybe_unused)
{
done = 1;
}
#if defined(__aarch64__)
/*
* Write leaf() in assembly so it stays as a minimal leaf function with no
* stack frame and won't get silently broken in the future by any Perf wide
* compilation options like -fstack-protector-all.
*/
asm(
".pushsection .text,\"ax\",%progbits\n"
".global leaf\n"
".type leaf, %function\n"
"leaf:\n"
" adrp x1, leafloop_done\n"
" ldr w2, [x1, #:lo12:leafloop_done]\n"
" cbz w2, leaf\n"
" ret\n"
".size leaf, .-leaf\n"
".popsection\n"
);
#else
noinline void leaf(void)
{
while (!done)
;
}
#endif
noinline void parent(void)
{
leaf();
}
static int leafloop(int argc, const char **argv)
{
int sec = 1;
if (argc > 0)
sec = atoi(argv[0]);
signal(SIGINT, sighandler);
signal(SIGALRM, sighandler);
alarm(sec);
parent();
return 0;
}
DEFINE_WORKLOAD(leafloop);
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