gwj / at91sam9263 · Commits

Commit 27463101f15bee17d2f46642c48a7373bc6c595e

Authored by aliguori
1 parent b8ae7553

Make compatfd fallback more robust 

Be more friendly when signalfd() fails, and also add configure checks to detect
that syscall(SYS_signalfd) actually works.  malc pointed out that some installs
do not have /usr/include/linux headers that are in sync with the glibc headers
so why SYS_signalfd is defined, it's #defined to _NR_signalfd which is not
defined in the /usr/include/linux header.

While this is a distro bug, it doesn't hurt to do a more thorough job in
detection.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5334 c046a42c-6fe2-441c-8c8c-71466251a162
Inline Side-by-side
Showing 3 changed files with 43 additions and 5 deletions
block-raw-posix.c
  View file @2746310
... ... @@ -584,6 +584,10 @@ static int posix_aio_init(void)
584 584  
585 585 s->first_aio = NULL;
586 586 s->fd = qemu_signalfd(&mask);
  587 + if (s->fd == -1) {
  588 + fprintf(stderr, "failed to create signalfd\n");
  589 + return -errno;
  590 + }
587 591  
588 592 fcntl(s->fd, F_SETFL, O_NONBLOCK);
589 593  
... ...
compatfd.c
  View file @2746310
... ... @@ -100,11 +100,11 @@ static int qemu_signalfd_compat(const sigset_t *mask)
100 100  
101 101 int qemu_signalfd(const sigset_t *mask)
102 102 {
103   -#if defined(SYS_signalfd)
  103 +#if defined(CONFIG_signalfd)
104 104 int ret;
105 105  
106 106 ret = syscall(SYS_signalfd, -1, mask, _NSIG / 8);
107   - if (!(ret == -1 && errno == ENOSYS))
  107 + if (ret != -1)
108 108 return ret;
109 109 #endif
110 110  
... ... @@ -113,15 +113,14 @@ int qemu_signalfd(const sigset_t *mask)
113 113  
114 114 int qemu_eventfd(int *fds)
115 115 {
116   -#if defined(SYS_eventfd)
  116 +#if defined(CONFIG_eventfd)
117 117 int ret;
118 118  
119 119 ret = syscall(SYS_eventfd, 0);
120 120 if (ret >= 0) {
121 121 fds[0] = fds[1] = ret;
122 122 return 0;
123   - } else if (!(ret == -1 && errno == ENOSYS))
124   - return ret;
  123 + }
125 124 #endif
126 125  
127 126 return pipe(fds);
... ...
configure
  View file @2746310
... ... @@ -110,6 +110,8 @@ curses=&quot;yes&quot;
110 110 aio="yes"
111 111 nptl="yes"
112 112 mixemu="no"
  113 +signalfd="no"
  114 +eventfd="no"
113 115  
114 116 # OS specific
115 117 targetos=`uname -s`
... ... @@ -901,6 +903,33 @@ EOF
901 903 fi
902 904 fi
903 905  
  906 +##########################################
  907 +# signalfd probe
  908 +cat > $TMPC << EOF
  909 +#define _GNU_SOURCE
  910 +#include <unistd.h>
  911 +#include <sys/syscall.h>
  912 +#include <signal.h>
  913 +int main(void) { return syscall(SYS_signalfd, -1, NULL, _NSIG / 8); }
  914 +EOF
  915 +
  916 +if $cc $ARCH_CFLAGS -o $TMPE $TMPC 2> /dev/null ; then
  917 + signalfd=yes
  918 +fi
  919 +
  920 +##########################################
  921 +# eventfd probe
  922 +cat > $TMPC << EOF
  923 +#define _GNU_SOURCE
  924 +#include <unistd.h>
  925 +#include <sys/syscall.h>
  926 +int main(void) { return syscall(SYS_eventfd, 0); }
  927 +EOF
  928 +
  929 +if $cc $ARCH_CFLAGS -o $TMPE $TMPC 2> /dev/null ; then
  930 + eventfd=yes
  931 +fi
  932 +
904 933 # Check if tools are available to build documentation.
905 934 if [ -x "`which texi2html 2>/dev/null`" ] && \
906 935 [ -x "`which pod2man 2>/dev/null`" ]; then
... ... @@ -1229,6 +1258,12 @@ if test &quot;$aio&quot; = &quot;yes&quot; ; then
1229 1258 echo "#define CONFIG_AIO 1" >> $config_h
1230 1259 echo "CONFIG_AIO=yes" >> $config_mak
1231 1260 fi
  1261 +if test "$signalfd" = "yes" ; then
  1262 + echo "#define CONFIG_signalfd 1" >> $config_h
  1263 +fi
  1264 +if test "$eventfd" = "yes" ; then
  1265 + echo "#define CONFIG_eventfd 1" >> $config_h
  1266 +fi
1232 1267  
1233 1268 # XXX: suppress that
1234 1269 if [ "$bsd" = "yes" ] ; then
... ...