Implement msleep_interruptible() in the LinuxKPI. While at it use pause_sbt()

instead of pause() in the msleep() function to avoid rounding errors when
converting delay values forth and back. Add a guard for a delay value
of zero milliseconds which is undefined.

MFC after:	1 week
Requested by:	Johannes Lundberg <johalun0@gmail.com>
Sponsored by:	Mellanox Technologies

2 files changed, 31 insertions, 3 deletions

diff --git a/sys/compat/linuxkpi/common/include/linux/delay.h b/sys/compat/linuxkpi/common/include/linux/delay.h
index da38662087e4..32997071c2ae 100644
--- a/sys/compat/linuxkpi/common/include/linux/delay.h
+++ b/sys/compat/linuxkpi/common/include/linux/delay.h
@@ -36,13 +36,19 @@
 #include <sys/systm.h>
 
 static inline void
-linux_msleep(int ms)
+linux_msleep(unsigned int ms)
 {
-	pause("lnxsleep", msecs_to_jiffies(ms));
+	/* guard against invalid values */
+	if (ms == 0)
+		ms = 1;
+	pause_sbt("lnxsleep", SBT_1MS * ms, 0, C_HARDCLOCK);
 }
 
 #undef msleep
-#define	msleep	linux_msleep
+#define	msleep(ms) linux_msleep(ms)
+
+#undef msleep_interruptible
+#define	msleep_interruptible(ms) linux_msleep_interruptible(ms)
 
 #define	udelay(t)	DELAY(t)
 
@@ -65,4 +71,6 @@ usleep_range(unsigned long min, unsigned long max)
 	DELAY(min);
 }
 
+extern unsigned int linux_msleep_interruptible(unsigned int ms);
+
 #endif	/* _LINUX_DELAY_H_ */
diff --git a/sys/compat/linuxkpi/common/src/linux_schedule.c b/sys/compat/linuxkpi/common/src/linux_schedule.c
index 0958b3a53ff2..b91164773c5b 100644
--- a/sys/compat/linuxkpi/common/src/linux_schedule.c
+++ b/sys/compat/linuxkpi/common/src/linux_schedule.c
@@ -33,6 +33,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/signalvar.h>
 #include <sys/sleepqueue.h>
 
+#include <linux/delay.h>
 #include <linux/errno.h>
 #include <linux/kernel.h>
 #include <linux/list.h>
@@ -74,6 +75,25 @@ linux_add_to_sleepqueue(void *wchan, struct task_struct *task,
 	return (ret);
 }
 
+unsigned int
+linux_msleep_interruptible(unsigned int ms)
+{
+	int ret;
+
+	/* guard against invalid values */
+	if (ms == 0)
+		ms = 1;
+	ret = -pause_sbt("lnxsleep", SBT_1MS * ms, 0, C_HARDCLOCK | C_CATCH);
+
+	switch (ret) {
+	case -EWOULDBLOCK:
+		return (0);
+	default:
+		linux_schedule_save_interrupt_value(current, ret);
+		return (ms);
+	}
+}
+
 static int
 wake_up_task(struct task_struct *task, unsigned int state)
 {