From: David Woodhouse <dwmw@amazon.co.uk>
Date: Thu, 28 Jan 2021 16:49:56 +0000 (+0000)
Subject: Timing debugging for bringup
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=5d2d4c99dbbb212a8c26798b27773e4f5819f50a;p=users%2Fdwmw2%2Flinux.git

Timing debugging for bringup

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
---

diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 5e78e01ca3b46..9eb0b9497855f 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -308,7 +308,7 @@ static void kvm_register_steal_time(void)
 		return;
 
 	wrmsrl(MSR_KVM_STEAL_TIME, (slow_virt_to_phys(st) | KVM_MSR_ENABLED));
-	pr_info("stealtime: cpu %d, msr %llx\n", cpu,
+	if (0)	pr_info("stealtime: cpu %d, msr %llx\n", cpu,
 		(unsigned long long) slow_virt_to_phys(st));
 }
 
diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c
index aa593743acf67..79a5c26c376e3 100644
--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c
@@ -108,7 +108,7 @@ static inline void kvm_sched_clock_init(bool stable)
 	kvm_sched_clock_offset = kvm_clock_read();
 	pv_ops.time.sched_clock = kvm_sched_clock_read;
 
-	pr_info("kvm-clock: using sched offset of %llu cycles",
+	if (0) pr_info("kvm-clock: using sched offset of %llu cycles",
 		kvm_sched_clock_offset);
 
 	BUILD_BUG_ON(sizeof(kvm_sched_clock_offset) >
@@ -184,7 +184,7 @@ static void kvm_register_clock(char *txt)
 
 	pa = slow_virt_to_phys(&src->pvti) | 0x01ULL;
 	wrmsrl(msr_kvm_system_time, pa);
-	pr_info("kvm-clock: cpu %d, msr %llx, %s", smp_processor_id(), pa, txt);
+	if (0)	pr_info("kvm-clock: cpu %d, msr %llx, %s", smp_processor_id(), pa, txt);
 }
 
 static void kvm_save_sched_clock_state(void)
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 649b8236309b3..881e60ed84fdd 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -373,7 +373,7 @@ int topology_update_die_map(unsigned int die, unsigned int cpu)
 		goto found;
 
 	new = logical_die++;
-	if (new != die) {
+	if (0 && new != die) {
 		pr_info("CPU %u Converting physical %u to logical die %u\n",
 			cpu, die, new);
 	}
@@ -1215,22 +1215,32 @@ unreg_nmi:
 
 int native_cpu_up(unsigned int cpu, struct task_struct *tidle)
 {
+	cycles_t t1, t2, t3, t4, t5;
 	int ret;
 
+	t1 = get_cycles();
 	ret = do_cpu_up(cpu, tidle);
 	if (ret)
 		return ret;
 
+	t2 = get_cycles();
 	ret = do_wait_cpu_initialized(cpu);
 	if (ret)
 		return ret;
 
+	t3 = get_cycles();
 	ret = do_wait_cpu_callin(cpu);
 	if (ret)
 		return ret;
 
+	t4 = get_cycles();
 	ret = do_wait_cpu_online(cpu);
 
+	t5 = get_cycles();
+
+	printk("CPU#%d up in %10lld,%10lld,%10lld,%10lld (%10lld)\n", cpu,
+	       t2-t1, t3-t2, t4-t3, t5-t4, t5-t1);
+
 	if (x86_platform.legacy.warm_reset) {
 		/*
 		 * Cleanup possible dangling ends...