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[tip:x86/apic] x86/msr: Add wrmsr_notrace()

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Commit-ID:  b2c5ea4f759190ee9f75687a00035c1a66d0d743
Gitweb:     http://git.kernel.org/tip/b2c5ea4f759190ee9f75687a00035c1a66d0d743
Author:     Wanpeng Li <wanpeng.li@hotmail.com>
AuthorDate: Mon, 7 Nov 2016 11:13:39 +0800
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Wed, 9 Nov 2016 22:03:14 +0100

x86/msr: Add wrmsr_notrace()

Required to remove the extra irq_enter()/irq_exit() in
smp_reschedule_interrupt().

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: kvm@vger.kernel.org
Cc: Mike Galbraith <efault@gmx.de>
Link: http://lkml.kernel.org/r/1478488420-5982-2-git-send-email-wanpeng.li@hotmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

---
 arch/x86/include/asm/msr.h | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/msr.h b/arch/x86/include/asm/msr.h
index b5fee97..9b0a232 100644
--- a/arch/x86/include/asm/msr.h
+++ b/arch/x86/include/asm/msr.h
@@ -115,17 +115,29 @@ static inline unsigned long long native_read_msr_safe(unsigned int msr,
 }
 
 /* Can be uninlined because referenced by paravirt */
-notrace static inline void native_write_msr(unsigned int msr,
+static notrace inline void __native_write_msr_notrace(unsigned int msr,
 					    unsigned low, unsigned high)
 {
 	asm volatile("1: wrmsr\n"
 		     "2:\n"
 		     _ASM_EXTABLE_HANDLE(1b, 2b, ex_handler_wrmsr_unsafe)
 		     : : "c" (msr), "a"(low), "d" (high) : "memory");
+}
+
+/* Can be uninlined because referenced by paravirt */
+static notrace inline void native_write_msr(unsigned int msr,
+					    unsigned low, unsigned high)
+{
+	__native_write_msr_notrace(msr, low, high);
 	if (msr_tracepoint_active(__tracepoint_write_msr))
 		do_trace_write_msr(msr, ((u64)high << 32 | low), 0);
 }
 
+static inline void wrmsr_notrace(unsigned msr, unsigned low, unsigned high)
+{
+	__native_write_msr_notrace(msr, low, high);
+}
+
 /* Can be uninlined because referenced by paravirt */
 notrace static inline int native_write_msr_safe(unsigned int msr,
 					unsigned low, unsigned high)

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[PATCH v8 1/2] x86/msr: Add write msr notrace  Wanpeng Li <kernellwp@gmail.com> - 2016-11-07 04:20 +0100
  [tip:x86/apic] x86/msr: Add wrmsr_notrace() tip-bot for Wanpeng Li <tipbot@zytor.com> - 2016-11-09 22:20 +0100

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