[PATCH] ppc64: replace schedule_timeout() with msleep_interruptible()

Use msleep_interruptible() instead of schedule_timeout() in ppc64-specific
code to cleanup/simplify the sleeping logic.  Change the units of the
parameter of do_event_scan_all_cpus() to milliseconds from jiffies.  The
return value of rtas_extended_busy_delay_time() was incorrectly being used
as a jiffies value (it is actually milliseconds), which is fixed by using
the value as a parameter to msleep_interruptible().  Also, use
rtas_extended_busy_delay_time() in another case where similar logic is
duplicated.

Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/ppc64/kernel/rtasd.c

@@ -19,6 +19,7 @@
 #include <linux/vmalloc.h>
 #include <linux/spinlock.h>
 #include <linux/cpu.h>
+#include <linux/delay.h>
 
 #include <asm/uaccess.h>
 #include <asm/io.h>
@@ -412,8 +413,7 @@ static void do_event_scan_all_cpus(long delay)
 
 		/* Drop hotplug lock, and sleep for the specified delay */
 		unlock_cpu_hotplug();
-		set_current_state(TASK_INTERRUPTIBLE);
-		schedule_timeout(delay);
+		msleep_interruptible(delay);
 		lock_cpu_hotplug();
 
 		cpu = next_cpu(cpu, cpu_online_map);
@@ -442,7 +442,7 @@ static int rtasd(void *unused)
 
 	printk(KERN_INFO "RTAS daemon started\n");
 
-	DEBUG("will sleep for %d jiffies\n", (HZ*60/rtas_event_scan_rate) / 2);
+	DEBUG("will sleep for %d milliseconds\n", (30000/rtas_event_scan_rate));
 
 	/* See if we have any error stored in NVRAM */
 	memset(logdata, 0, rtas_error_log_max);
@@ -459,7 +459,7 @@ static int rtasd(void *unused)
 	}
 
 	/* First pass. */
-	do_event_scan_all_cpus(HZ);
+	do_event_scan_all_cpus(1000);
 
 	if (surveillance_timeout != -1) {
 		DEBUG("enabling surveillance\n");
@@ -471,7 +471,7 @@ static int rtasd(void *unused)
 	 * machines have problems if we call event-scan too
 	 * quickly. */
 	for (;;)
-		do_event_scan_all_cpus((HZ*60/rtas_event_scan_rate) / 2);
+		do_event_scan_all_cpus(30000/rtas_event_scan_rate);
 
 error:
 	/* Should delete proc entries */

arch/ppc64/kernel/rtc.c

@@ -35,6 +35,7 @@
 #include <linux/spinlock.h>
 #include <linux/bcd.h>
 #include <linux/interrupt.h>
+#include <linux/delay.h>
 
 #include <asm/io.h>
 #include <asm/uaccess.h>
@@ -351,8 +352,7 @@ void rtas_get_rtc_time(struct rtc_time *rtc_tm)
 				return;	/* delay not allowed */
 			}
 			wait_time = rtas_extended_busy_delay_time(error);
-			set_current_state(TASK_INTERRUPTIBLE);
-			schedule_timeout(wait_time);
+			msleep_interruptible(wait_time);
 			error = RTAS_CLOCK_BUSY;
 		}
 	} while (error == RTAS_CLOCK_BUSY && (__get_tb() < max_wait_tb));
@@ -386,8 +386,7 @@ int rtas_set_rtc_time(struct rtc_time *tm)
 			if (in_interrupt())
 				return 1;	/* probably decrementer */
 			wait_time = rtas_extended_busy_delay_time(error);
-			set_current_state(TASK_INTERRUPTIBLE);
-			schedule_timeout(wait_time);
+			msleep_interruptible(wait_time);
 			error = RTAS_CLOCK_BUSY;
 		}
 	} while (error == RTAS_CLOCK_BUSY && (__get_tb() < max_wait_tb));

arch/ppc64/kernel/scanlog.c

@@ -25,6 +25,7 @@
 #include <linux/errno.h>
 #include <linux/proc_fs.h>
 #include <linux/init.h>
+#include <linux/delay.h>
 #include <asm/uaccess.h>
 #include <asm/rtas.h>
 #include <asm/prom.h>
@@ -77,7 +78,7 @@ static ssize_t scanlog_read(struct file *file, char __user *buf,
 		return -EFAULT;
 
 	for (;;) {
-		wait_time = HZ/2;	/* default wait if no data */
+		wait_time = 500;	/* default wait if no data */
 		spin_lock(&rtas_data_buf_lock);
 		memcpy(rtas_data_buf, data, RTAS_DATA_BUF_SIZE);
 		status = rtas_call(ibm_scan_log_dump, 2, 1, NULL,
@@ -107,24 +108,14 @@ static ssize_t scanlog_read(struct file *file, char __user *buf,
 			break;
 		    default:
 			if (status > 9900 && status <= 9905) {
-				/* No data.  RTAS is hinting at a delay required
-				 * between 1-100000 milliseconds
-				 */
-				int ms = 1;
-				for (; status > 9900; status--)
-					ms = ms * 10;
-				/* Use microseconds for reasonable accuracy */
-				ms *= 1000;
-				wait_time = ms / (1000000/HZ); /* round down is fine */
-				/* Fall through to sleep */
+				wait_time = rtas_extended_busy_delay_time(status);
 			} else {
 				printk(KERN_ERR "scanlog: unknown error from rtas: %d\n", status);
 				return -EIO;
 			}
 		}
 		/* Apparently no data yet.  Wait and try again. */
-		set_current_state(TASK_INTERRUPTIBLE);
-		schedule_timeout(wait_time);
+		msleep_interruptible(wait_time);
 	}
 	/*NOTREACHED*/
 }