projects/linux·commit e7d476df

flag parameters: NONBLOCK in eventfd

e7d476df · Ulrich Drepper <[email protected]> · 2008-07-23 21:29:38 -07:00

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 <[email protected]>
Acked-by: Davide Libenzi <[email protected]>
Cc: Michael Kerrisk <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Commit
e7d476dfdf0bcfed478a207aecfdc84f81efecaf
Parents
5fb5e049

Changes

2 files changed · +4 −3

FileStatusAddDelContent
fs/eventfd.cmodified+2−2View file
include/linux/eventfd.hmodified+2−1View file

fs/eventfd.c

View file
diff --git a/fs/eventfd.c b/fs/eventfd.c
index bd420e6..3ed4466 100644
--- a/fs/eventfd.c
+++ b/fs/eventfd.c
@@ -203,7 +203,7 @@ asmlinkage long sys_eventfd2(unsigned int count, int flags)
int fd;
struct eventfd_ctx *ctx;
- if (flags & ~EFD_CLOEXEC)
+ if (flags & ~(EFD_CLOEXEC | EFD_NONBLOCK))
return -EINVAL;
ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
@@ -218,7 +218,7 @@ asmlinkage long sys_eventfd2(unsigned int count, int flags)
* anon_inode_getfd() will install the fd.
*/
fd = anon_inode_getfd("[eventfd]", &eventfd_fops, ctx,
- flags & O_CLOEXEC);
+ flags & (O_CLOEXEC | O_NONBLOCK));
if (fd < 0)
kfree(ctx);
return fd;

include/linux/eventfd.h

View file
diff --git a/include/linux/eventfd.h b/include/linux/eventfd.h
index a6c0eae..a667637 100644
--- a/include/linux/eventfd.h
+++ b/include/linux/eventfd.h
@@ -10,11 +10,12 @@
#ifdef CONFIG_EVENTFD
-/* For O_CLOEXEC */
+/* 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);