[PATCH RESEND] Calling check_system_tsc_reliable() before unsynchronized_tsc()

From	Zhenzhong Duan <zhenzhong.duan@oracle.com>
Newsgroups	linux.kernel
Subject	[PATCH RESEND] Calling check_system_tsc_reliable() before unsynchronized_tsc()
Date	2017-06-21 10:30 +0200
Message-ID	<tUJbr-3H5-1@gated-at.bofh.it> (permalink)
Organization	linux.* mail to news gateway

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unsynchronized_tsc() checks value of tsc_clocksource_reliable which is set by
check_system_tsc_reliable(). It's better to move check_system_tsc_reliable() at
front.

Though X86_FEATURE_CONSTANT_TSC is usually set for TSC reliable system, just in
case.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
---
 arch/x86/kernel/tsc.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index 714dfba..a316bdd 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -1412,11 +1412,11 @@ void __init tsc_init(void)
 
 	use_tsc_delay();
 
+	check_system_tsc_reliable();
+
 	if (unsynchronized_tsc())
 		mark_tsc_unstable("TSCs unsynchronized");
 
-	check_system_tsc_reliable();
-
 	detect_art();
 }
 
-- 
1.7.3

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[PATCH RESEND] Calling check_system_tsc_reliable() before  unsynchronized_tsc() Zhenzhong Duan <zhenzhong.duan@oracle.com> - 2017-06-21 10:30 +0200
  Re: [PATCH RESEND] Calling check_system_tsc_reliable() before  unsynchronized_tsc() Thomas Gleixner <tglx@linutronix.de> - 2017-06-22 16:00 +0200
    Re: [PATCH RESEND] Calling check_system_tsc_reliable() before  unsynchronized_tsc() Zhenzhong Duan <zhenzhong.duan@oracle.com> - 2017-06-23 10:40 +0200
  [tip:x86/timers] x86/tsc: Call check_system_tsc_reliable() before  unsynchronized_tsc() tip-bot for Zhenzhong Duan <tipbot@zytor.com> - 2017-06-22 16:10 +0200

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