[PATCH] Add debug to Thiago's patch

[Gautham R. Shenoy]

Also, add debug for callers of rtas-start-cpu and rtas-set-power-level

Signed-off-by: Gautham R. Shenoy <ego@xxxxxxxxxxxxxxxxxx>
---
 arch/powerpc/kernel/rtas.c                   |  1 +
 arch/powerpc/platforms/pseries/hotplug-cpu.c | 10 ++++++++++
 arch/powerpc/platforms/pseries/smp.c         |  2 ++
 3 files changed, 13 insertions(+)

diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c
index de35bd8f..9ecf957 100644
--- a/arch/powerpc/kernel/rtas.c
+++ b/arch/powerpc/kernel/rtas.c
@@ -576,6 +576,7 @@ int rtas_set_power_level(int powerdomain, int level, int *setlevel)
 		return -ENOENT;
 
 	do {
+		printk("CPU %d calling rtas-set-power-level\n", smp_processor_id());
 		rc = rtas_call(token, 2, 2, setlevel, powerdomain, level);
 	} while (rtas_busy_delay(rc));
 
diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c
index fad3ceb..3dab7c3 100644
--- a/arch/powerpc/platforms/pseries/hotplug-cpu.c
+++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c
@@ -214,6 +214,10 @@ static void pseries_cpu_die(unsigned int cpu)
 			msleep(1);
 		}
 	} else if (get_preferred_offline_state(cpu) == CPU_STATE_OFFLINE) {
+		u64 tb_before = mftb();
+		u64 tb_after;
+
+		printk("[DEBUG] CPU %d waiting for CPU %d to enter rtas\n", smp_processor_id(), cpu);
 		/*
 		 * If the current state is not offline yet, it means that the
 		 * dying CPU (which is in pseries_mach_cpu_die) didn't have a
@@ -230,6 +234,12 @@ static void pseries_cpu_die(unsigned int cpu)
 				break;
 			udelay(100);
 		}
+
+		tb_after = mftb();
+
+		printk("[DEBUG] CPU %d noticed CPU %d enter rtas: tries=%d, time=%llu\n",
+			smp_processor_id(), cpu, tries,
+			div_u64(tb_after - tb_before, tb_ticks_per_usec));
 	}
 
 	if (cpu_status != 0) {
diff --git a/arch/powerpc/platforms/pseries/smp.c b/arch/powerpc/platforms/pseries/smp.c
index 3df4612..d4624c4 100644
--- a/arch/powerpc/platforms/pseries/smp.c
+++ b/arch/powerpc/platforms/pseries/smp.c
@@ -123,6 +123,8 @@ static inline int smp_startup_cpu(unsigned int lcpu)
 	if (start_cpu == RTAS_UNKNOWN_SERVICE)
 		return 1;
 
+	printk("CPU %d calling start-cpu for CPU %d\n",
+	       smp_processor_id(), lcpu);
 	status = rtas_call(start_cpu, 3, 1, NULL, pcpu, start_here, pcpu);
 	if (status != 0) {
 		printk(KERN_ERR "start-cpu failed: %i\n", status);
-- 
1.9.4


--
Thanks and Regards
gautham.