[Qemu-devel] [PATCH][RFC] Fire SIGIO when IO requests are completed

[Anthony Liguori]

Hi Blue Swirl,

Can you test the attached patch with sparc-softmmu?  Better yet, do you 
have an image, or a recipe for an image that I could use to try and 
reproduce the problem?  The sparc test code on the QEMU website just 
uses a ram disk so the regression isn't evident with it.

Regards,

Anthony Liguori

diff --git a/block-raw-posix.c b/block-raw-posix.c
index c0404fa..9b136ee 100644
--- a/block-raw-posix.c
+++ b/block-raw-posix.c
@@ -591,6 +591,12 @@ static int posix_aio_init(void)
 
     fcntl(s->fd, F_SETFL, O_NONBLOCK);
 
+    {
+       extern void enable_sigio_timer(int fd);
+
+       enable_sigio_timer(s->fd);
+    }
+
     qemu_aio_set_fd_handler(s->fd, posix_aio_read, NULL, posix_aio_flush, s);
 
 #if defined(__linux__)
diff --git a/qemu-tool.c b/qemu-tool.c
index 63e2056..c37fdea 100644
--- a/qemu-tool.c
+++ b/qemu-tool.c
@@ -26,6 +26,10 @@ struct QEMUBH
     void *opaque;
 };
 
+void enable_sigio_timer(int fd)
+{
+}
+
 void term_printf(const char *fmt, ...)
 {
 }
diff --git a/vl.c b/vl.c
index c94fdc0..8f66a90 100644
--- a/vl.c
+++ b/vl.c
@@ -1307,7 +1307,7 @@ static void host_alarm_handler(int host_signum)
         last_clock = ti;
     }
 #endif
-    if (alarm_has_dynticks(alarm_timer) ||
+    if (1 || alarm_has_dynticks(alarm_timer) ||
         (!use_icount &&
             qemu_timer_expired(active_timers[QEMU_TIMER_VIRTUAL],
                                qemu_get_clock(vm_clock))) ||
@@ -1383,7 +1383,7 @@ static uint64_t qemu_next_deadline_dyntick(void)
 
 #define RTC_FREQ 1024
 
-static void enable_sigio_timer(int fd)
+void enable_sigio_timer(int fd)
 {
     struct sigaction act;
 
@@ -1393,7 +1393,7 @@ static void enable_sigio_timer(int fd)
     act.sa_handler = host_alarm_handler;
 
     sigaction(SIGIO, &act, NULL);
-    fcntl(fd, F_SETFL, O_ASYNC);
+    fcntl(fd, F_SETFL, O_ASYNC | fcntl(fd, F_GETFL));
     fcntl(fd, F_SETOWN, getpid());
 }