[POWERPC] pseries: Avoid excess rtas_token calls

We don't need to look up the rtas event token once per
cpu per second.  This avoids some misc device-tree lookups
and string ops and so provides some minor performance
improvement.

Signed-off-by: Linas Vepstas <linas@austin.ibm.com>

----
Revised commit-log message.

 arch/powerpc/platforms/pseries/rtasd.c |   15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 9 insertions, 6 deletions

diff --git a/arch/powerpc/platforms/pseries/rtasd.c b/arch/powerpc/platforms/pseries/rtasd.c
index 9797b10b293..762fe87629f 100644
--- a/arch/powerpc/platforms/pseries/rtasd.c
+++ b/arch/powerpc/platforms/pseries/rtasd.c
@@ -44,10 +44,13 @@ static unsigned long rtas_log_start;
 static unsigned long rtas_log_size;
 
 static int surveillance_timeout = -1;
-static unsigned int rtas_event_scan_rate;
 static unsigned int rtas_error_log_max;
 static unsigned int rtas_error_log_buffer_max;
 
+/* RTAS service tokens */
+static unsigned int event_scan;
+static unsigned int rtas_event_scan_rate;
+
 static int full_rtas_msgs = 0;
 
 extern int no_logging;
@@ -381,7 +384,7 @@ static int get_eventscan_parms(void)
         return 0;
 }
 
-static void do_event_scan(int event_scan)
+static void do_event_scan(void)
 {
         int error;
         do {
@@ -408,7 +411,7 @@ static void do_event_scan_all_cpus(long delay)
         cpu = first_cpu(cpu_online_map);
         for (;;) {
                 set_cpus_allowed(current, cpumask_of_cpu(cpu));
-                do_event_scan(rtas_token("event-scan"));
+                do_event_scan();
                 set_cpus_allowed(current, CPU_MASK_ALL);
 
                 /* Drop hotplug lock, and sleep for the specified delay */
@@ -426,12 +429,11 @@ static void do_event_scan_all_cpus(long delay)
 static int rtasd(void *unused)
 {
         unsigned int err_type;
-        int event_scan = rtas_token("event-scan");
         int rc;
 
         daemonize("rtasd");
 
-        if (event_scan == RTAS_UNKNOWN_SERVICE || get_eventscan_parms() == -1)
+        if (get_eventscan_parms() == -1)
                 goto error;
 
         rtas_log_buf = vmalloc(rtas_error_log_buffer_max*LOG_NUMBER);
@@ -486,7 +488,8 @@ static int __init rtas_init(void)
                 return 0;
 
         /* No RTAS */
-        if (rtas_token("event-scan") == RTAS_UNKNOWN_SERVICE) {
+        event_scan = rtas_token("event-scan");
+        if (event_scan == RTAS_UNKNOWN_SERVICE) {
                 printk(KERN_DEBUG "rtasd: no event-scan on system\n");
                 return -ENODEV;
         }