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 <s.vorobiov@samsung.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
		
			
				
	
	
		
			47 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			47 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * GLIB Compatibility Functions
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 *
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 * Copyright IBM, Corp. 2013
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 *
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 * Authors:
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 *  Anthony Liguori   <aliguori@us.ibm.com>
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 *
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 * This work is licensed under the terms of the GNU GPL, version 2 or later.
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 * See the COPYING file in the top-level directory.
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 *
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 */
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#ifndef QEMU_GLIB_COMPAT_H
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#define QEMU_GLIB_COMPAT_H
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#include <glib.h>
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#if !GLIB_CHECK_VERSION(2, 14, 0)
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static inline guint g_timeout_add_seconds(guint interval, GSourceFunc function,
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                                          gpointer data)
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{
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    return g_timeout_add(interval * 1000, function, data);
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}
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#endif
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#ifdef _WIN32
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/*
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 * g_poll has a problem on Windows when using
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 * timeouts < 10ms, so use wrapper.
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 */
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#define g_poll(fds, nfds, timeout) g_poll_fixed(fds, nfds, timeout)
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gint g_poll_fixed(GPollFD *fds, guint nfds, gint timeout);
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#elif !GLIB_CHECK_VERSION(2, 20, 0)
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/*
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 * Glib before 2.20.0 doesn't implement g_poll, so wrap it to compile properly
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 * on older systems.
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 */
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static inline gint g_poll(GPollFD *fds, guint nfds, gint timeout)
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{
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    GMainContext *ctx = g_main_context_default();
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    return g_main_context_get_poll_func(ctx)(fds, nfds, timeout);
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}
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#endif
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#endif
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