linux-kernel - [PATCH 11/11] x86/kvm: Silence per-cpu pr_info noise about KVM clocks and steal time

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Message-Id: <20211209150938.3518-12-dwmw2@infradead.org>
Date:   Thu,  9 Dec 2021 15:09:38 +0000
From:   David Woodhouse <dwmw2@...radead.org>
To:     Thomas Gleixner <tglx@...utronix.de>
Cc:     Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
        Dave Hansen <dave.hansen@...ux.intel.com>, x86@...nel.org,
        "H. Peter Anvin" <hpa@...or.com>,
        Paolo Bonzini <pbonzini@...hat.com>,
        "Paul E. McKenney" <paulmck@...nel.org>,
        linux-kernel@...r.kernel.org, kvm@...r.kernel.org,
        rcu@...r.kernel.org, mimoja@...oja.de, hewenliang4@...wei.com,
        hushiyuan@...wei.com, luolongjun@...wei.com, hejingxian@...wei.com
Subject: [PATCH 11/11] x86/kvm: Silence per-cpu pr_info noise about KVM clocks and steal time

From: David Woodhouse <dwmw@...zon.co.uk>

I made the actual CPU bringup go nice and fast... and then Linux spends
half a minute printing stupid nonsense about clocks and steal time for
each of 256 vCPUs. Don't do that. Nobody cares.

Signed-off-by: David Woodhouse <dwmw@...zon.co.uk>
---
 arch/x86/kernel/kvm.c      | 6 +++---
 arch/x86/kernel/kvmclock.c | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 59abbdad7729..a438217cbfac 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -313,7 +313,7 @@ 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,
+	pr_debug("stealtime: cpu %d, msr %llx\n", cpu,
 		(unsigned long long) slow_virt_to_phys(st));
 }
 
@@ -350,7 +350,7 @@ static void kvm_guest_cpu_init(void)
 
 		wrmsrl(MSR_KVM_ASYNC_PF_EN, pa);
 		__this_cpu_write(apf_reason.enabled, 1);
-		pr_info("setup async PF for cpu %d\n", smp_processor_id());
+		pr_debug("setup async PF for cpu %d\n", smp_processor_id());
 	}
 
 	if (kvm_para_has_feature(KVM_FEATURE_PV_EOI)) {
@@ -376,7 +376,7 @@ static void kvm_pv_disable_apf(void)
 	wrmsrl(MSR_KVM_ASYNC_PF_EN, 0);
 	__this_cpu_write(apf_reason.enabled, 0);
 
-	pr_info("disable async PF for cpu %d\n", smp_processor_id());
+	pr_debug("disable async PF for cpu %d\n", smp_processor_id());
 }
 
 static void kvm_disable_steal_time(void)
diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c
index 462dd8e9b03d..a35cbf9107af 100644
--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c
@@ -174,7 +174,7 @@ 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);
+	pr_debug("kvm-clock: cpu %d, msr %llx, %s", smp_processor_id(), pa, txt);
 }
 
 static void kvm_save_sched_clock_state(void)
-- 
2.31.1