From 5a007547df76446ab891df93ebc55749716609bf Mon Sep 17 00:00:00 2001 From: Sangho Park Date: Thu, 8 May 2014 12:47:10 +0400 Subject: glib: fix g_poll early timeout on windows g_poll has a problem on Windows when using timeouts < 10ms, in glib/gpoll.c: /* If not, and we have a significant timeout, poll again with * timeout then. Note that this will return indication for only * one event, or only for messages. We ignore timeouts less than * ten milliseconds as they are mostly pointless on Windows, the * MsgWaitForMultipleObjectsEx() call will timeout right away * anyway. */ if (retval == 0 && (timeout == INFINITE || timeout >= 10)) retval = poll_rest (poll_msgs, handles, nhandles, fds, nfds, timeout); so whenever g_poll is called with timeout < 10ms it does a quick poll instead of wait, this causes significant performance degradation of QEMU, thus we should use WaitForMultipleObjectsEx directly Signed-off-by: Stanislav Vorobiov Signed-off-by: Stefan Hajnoczi --- include/glib-compat.h | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'include/glib-compat.h') diff --git a/include/glib-compat.h b/include/glib-compat.h index 8d25900700..1280fb2c1f 100644 --- a/include/glib-compat.h +++ b/include/glib-compat.h @@ -24,7 +24,14 @@ static inline guint g_timeout_add_seconds(guint interval, GSourceFunc function, } #endif -#if !GLIB_CHECK_VERSION(2, 20, 0) +#ifdef _WIN32 +/* + * g_poll has a problem on Windows when using + * timeouts < 10ms, so use wrapper. + */ +#define g_poll(fds, nfds, timeout) g_poll_fixed(fds, nfds, timeout) +gint g_poll_fixed(GPollFD *fds, guint nfds, gint timeout); +#elif !GLIB_CHECK_VERSION(2, 20, 0) /* * Glib before 2.20.0 doesn't implement g_poll, so wrap it to compile properly * on older systems. -- cgit v1.2.3