From: Thorsten Kukuk <kukuk@suse.de>
To: libc-hacker@sources.redhat.com
Subject: deadlock in signal handler with NPTL
Date: Tue, 22 Jun 2004 21:51:00 -0000 [thread overview]
Message-ID: <20040622215059.GA1204@suse.de> (raw)
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Hi,
I got the following test program. I know, it is very ugly and there
are a lot of things somebody should not do, but this is something
what programs like sshd are doing.
The problem is: This program deadlocks very fast in a FUTEX_WAIT
call. This does not happen with LinuxThreads.
Any ideas what goes wrong?
Thorsten
--
Thorsten Kukuk http://www.suse.de/~kukuk/ kukuk@suse.de
SuSE Linux AG Maxfeldstr. 5 D-90409 Nuernberg
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Key fingerprint = A368 676B 5E1B 3E46 CFCE 2D97 F8FD 4E23 56C6 FB4B
[-- Attachment #2: s.c --]
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#include <sys/types.h>
#include <unistd.h>
#include <stdio.h>
#include <syslog.h>
#include <signal.h>
void
handler(int sig)
{
syslog(LOG_DEBUG, "sigtest");
printf("in handler\n");
fflush(stdout);
}
int
main(int argc, char *argv[])
{
pid_t pid;
switch (pid = fork()) {
case 0:
break;
case -1:
perror("form");
exit(1);
default:
signaller(pid);
exit(0);
}
signal(SIGCHLD, handler);
while (1) {
syslog(LOG_DEBUG, "test");
printf("in loop\n");
fflush(stdout);
}
}
int
signaller(pid_t pid)
{
while (1) {
usleep(1);
kill(pid, SIGCHLD);
}
}
next reply other threads:[~2004-06-22 21:51 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-06-22 21:51 Thorsten Kukuk [this message]
2004-06-22 22:07 ` Jakub Jelinek
2004-06-23 4:26 ` Thorsten Kukuk
2004-06-23 4:41 ` Steve Munroe
2004-06-23 6:56 ` Thorsten Kukuk
2004-06-23 8:23 ` Jakub Jelinek
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