diff --git a/sys/compat/linuxkpi/common/include/linux/delay.h b/sys/compat/linuxkpi/common/include/linux/delay.h
index 1ed9dffed359..c13a1797adf9 100644
--- a/sys/compat/linuxkpi/common/include/linux/delay.h
+++ b/sys/compat/linuxkpi/common/include/linux/delay.h
@@ -1,79 +1,89 @@
 /*-
  * Copyright (c) 2010 Isilon Systems, Inc.
  * Copyright (c) 2010 iX Systems, Inc.
  * Copyright (c) 2010 Panasas, Inc.
  * Copyright (c) 2013-2021 Mellanox Technologies, Ltd.
  * Copyright (c) 2014 François Tigeot
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice unmodified, this list of conditions, and the following
  *    disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  * $FreeBSD$
  */
 #ifndef _LINUX_DELAY_H_
 #define	_LINUX_DELAY_H_
 
 #include <linux/jiffies.h>
 #include <sys/systm.h>
 
 static inline void
 linux_msleep(unsigned int ms)
 {
 	/* guard against invalid values */
 	if (ms == 0)
 		ms = 1;
 	pause_sbt("lnxsleep", mstosbt(ms), 0, C_HARDCLOCK);
 }
 
 #undef msleep
 #define	msleep(ms) linux_msleep(ms)
 
 #undef msleep_interruptible
 #define	msleep_interruptible(ms) linux_msleep_interruptible(ms)
 
 #define	udelay(t)	DELAY(t)
 
 static inline void
 mdelay(unsigned long msecs)
 {
 	while (msecs--)
 		DELAY(1000);
 }
 
 static inline void
 ndelay(unsigned long x)
 {
 	DELAY(howmany(x, 1000));
 }
 
 static inline void
 usleep_range(unsigned long min, unsigned long max)
 {
 	/* guard against invalid values */
 	if (min == 0)
 		min = 1;
 	pause_sbt("lnxsleep", ustosbt(min), 0, C_HARDCLOCK);
 }
 
 extern unsigned int linux_msleep_interruptible(unsigned int ms);
 
+static inline void
+fsleep(unsigned long us)
+{
+
+	if (us < 10)
+		udelay(us);
+	else
+		usleep_range(us, us);
+}
+
 #endif	/* _LINUX_DELAY_H_ */