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From: Cyril Hrubis <chrubis@suse.cz>
To: ltp@lists.linux.it
Subject: [LTP] [PATCH 1/2] syscalls/tkill: Convert tkill01 to the new API
Date: Wed, 28 Apr 2021 14:11:45 +0200	[thread overview]
Message-ID: <YIlRAanTIk9uKVEP@yuki> (raw)
In-Reply-To: <YIaWnt5ksxVyBvxk@pevik>

Hi!
> > -#include "test.h"
> >  #include "lapi/syscalls.h"
> > +#include "tst_test.h"
> 
> > +int sig_flag = 0;
> 
> It should be
> static int sig_flag;

It has to be volatile as well, if we are waiting in a bussy loop on it
and it's changed ansynchronously from a signal handler, otherwise
compiler may misoptimize the code.

Generally the code that waits for a signal should look like:

static volatile sig_atomic_t sig_flag;

static void setup(void)
{
	SAFE_SIGNAL(SIGUSR1, sighandler);
}

static void run(void)
{
	int timeout_ms = 1000;
	sig_flag = 0;

	TST_EXP_PASS(tst_syscall(__NR_tkill, tid, SIGUSR1));

	while (timeout_ms--) {
		if (sig_flag)
			break;

		usleep(1000);
	}

	if (sig_flag)
		tst_res(TPASS, ...);
	else
		tst_res(TFAIL, ...);
}

-- 
Cyril Hrubis
chrubis@suse.cz

  parent reply	other threads:[~2021-04-28 12:11 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-22  6:57 [LTP] [PATCH 0/2] syscalls/tkill: Convert tkill{01, 02} to the new API Xie Ziyao
2021-04-22  6:57 ` [LTP] [PATCH 1/2] syscalls/tkill: Convert tkill01 " Xie Ziyao
2021-04-26 10:31   ` Petr Vorel
2021-04-26 11:24     ` xieziyao
2021-04-26 12:55       ` Petr Vorel
2021-04-27  1:49         ` xieziyao
2021-04-28 12:11     ` Cyril Hrubis [this message]
2021-04-28 18:04       ` Petr Vorel
2021-04-29  2:02         ` xieziyao
2021-04-22  6:57 ` [LTP] [PATCH 2/2] syscalls/tkill: Convert tkill02 " Xie Ziyao
2021-04-26 11:12   ` Petr Vorel
2021-04-26 11:35     ` xieziyao

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