linux-kernel - [PATCH] x86: move turbo_disabled() out of intel_set_max_freq

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Date:   Wed, 29 Apr 2020 09:50:07 +0800
From:   Li RongQing <lirongqing@...du.com>
To:     tglx@...utronix.de, mingo@...hat.com, bp@...en8.de, hpa@...or.com,
        x86@...nel.org, peterz@...radead.org, ggherdovich@...e.cz,
        linux-kernel@...r.kernel.org, rafael.j.wysocki@...el.com
Subject: [PATCH] x86: move turbo_disabled() out of intel_set_max_freq_ratio

move the turbo_disabled before intel_set_max_freq_ratio,
when turbo is disabled, the max frequency ratio is a const
value, it is unnecessary to read MSR_TURBO_RATIO* msr to
compute

Signed-off-by: Li RongQing <lirongqing@...du.com>
---
 arch/x86/kernel/smpboot.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index fe3ab9632f3b..8979c459df2f 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -1987,7 +1987,7 @@ static bool intel_set_max_freq_ratio(void)
 out:
 	arch_turbo_freq_ratio = div_u64(turbo_freq * SCHED_CAPACITY_SCALE,
 					base_freq);
-	arch_set_max_freq_ratio(turbo_disabled());
+	arch_set_max_freq_ratio(false);
 	return true;
 }
 
@@ -2009,6 +2009,9 @@ static void init_freq_invariance(void)
 	if (smp_processor_id() != 0 || !boot_cpu_has(X86_FEATURE_APERFMPERF))
 		return;
 
+	if (turbo_disabled())
+		return;
+
 	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
 		ret = intel_set_max_freq_ratio();
 
-- 
2.16.2