mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
synced 2025-10-27 06:03:56 +00:00
This patch adds support for the EFD_NONBLOCK flag to eventfd2. The
additional changes needed are minimal.
The following test must be adjusted for architectures other than x86 and
x86-64 and in case the syscall numbers changed.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/syscall.h>
#ifndef __NR_eventfd2
# ifdef __x86_64__
# define __NR_eventfd2 290
# elif defined __i386__
# define __NR_eventfd2 328
# else
# error "need __NR_eventfd2"
# endif
#endif
#define EFD_NONBLOCK O_NONBLOCK
int
main (void)
{
int fd = syscall (__NR_eventfd2, 1, 0);
if (fd == -1)
{
puts ("eventfd2(0) failed");
return 1;
}
int fl = fcntl (fd, F_GETFL);
if (fl == -1)
{
puts ("fcntl failed");
return 1;
}
if (fl & O_NONBLOCK)
{
puts ("eventfd2(0) sets non-blocking mode");
return 1;
}
close (fd);
fd = syscall (__NR_eventfd2, 1, EFD_NONBLOCK);
if (fd == -1)
{
puts ("eventfd2(EFD_NONBLOCK) failed");
return 1;
}
fl = fcntl (fd, F_GETFL);
if (fl == -1)
{
puts ("fcntl failed");
return 1;
}
if ((fl & O_NONBLOCK) == 0)
{
puts ("eventfd2(EFD_NONBLOCK) does not set non-blocking mode");
return 1;
}
close (fd);
puts ("OK");
return 0;
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Acked-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
33 lines
618 B
C
33 lines
618 B
C
/*
|
|
* include/linux/eventfd.h
|
|
*
|
|
* Copyright (C) 2007 Davide Libenzi <davidel@xmailserver.org>
|
|
*
|
|
*/
|
|
|
|
#ifndef _LINUX_EVENTFD_H
|
|
#define _LINUX_EVENTFD_H
|
|
|
|
#ifdef CONFIG_EVENTFD
|
|
|
|
/* For O_CLOEXEC and O_NONBLOCK */
|
|
#include <linux/fcntl.h>
|
|
|
|
/* Flags for eventfd2. */
|
|
#define EFD_CLOEXEC O_CLOEXEC
|
|
#define EFD_NONBLOCK O_NONBLOCK
|
|
|
|
struct file *eventfd_fget(int fd);
|
|
int eventfd_signal(struct file *file, int n);
|
|
|
|
#else /* CONFIG_EVENTFD */
|
|
|
|
#define eventfd_fget(fd) ERR_PTR(-ENOSYS)
|
|
static inline int eventfd_signal(struct file *file, int n)
|
|
{ return 0; }
|
|
|
|
#endif /* CONFIG_EVENTFD */
|
|
|
|
#endif /* _LINUX_EVENTFD_H */
|
|
|