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[Xen-devel] [PATCH 01/10] x86/ticketlocks: remove obsolete comment

To: "H. Peter Anvin" <hpa@xxxxxxxxx>
Subject: [Xen-devel] [PATCH 01/10] x86/ticketlocks: remove obsolete comment
From: Jeremy Fitzhardinge <jeremy@xxxxxxxx>
Date: Wed, 14 Sep 2011 17:31:33 -0700
Cc: Marcelo Tosatti <mtosatti@xxxxxxxxxx>, Nick Piggin <npiggin@xxxxxxxxx>, KVM <kvm@xxxxxxxxxxxxxxx>, Peter Zijlstra <peterz@xxxxxxxxxxxxx>, the arch/x86 maintainers <x86@xxxxxxxxxx>, Linux Kernel Mailing List <linux-kernel@xxxxxxxxxxxxxxx>, Andi Kleen <andi@xxxxxxxxxxxxxx>, Avi Kivity <avi@xxxxxxxxxx>, Jeremy Fitzhardinge <jeremy.fitzhardinge@xxxxxxxxxx>, Ingo Molnar <mingo@xxxxxxx>, Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>, Xen Devel <xen-devel@xxxxxxxxxxxxxxxxxxx>
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From: Jeremy Fitzhardinge <jeremy.fitzhardinge@xxxxxxxxxx>

The note about partial registers is not really relevent now that we
rely on gcc to generate all the assembler.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@xxxxxxxxxx>
---
 arch/x86/include/asm/spinlock.h |    4 ----
 1 files changed, 0 insertions(+), 4 deletions(-)

diff --git a/arch/x86/include/asm/spinlock.h b/arch/x86/include/asm/spinlock.h
index f5695ee..972c260 100644
--- a/arch/x86/include/asm/spinlock.h
+++ b/arch/x86/include/asm/spinlock.h
@@ -49,10 +49,6 @@
  * issues and should be optimal for the uncontended case. Note the tail must be
  * in the high part, because a wide xadd increment of the low part would carry
  * up and contaminate the high part.
- *
- * With fewer than 2^8 possible CPUs, we can use x86's partial registers to
- * save some instructions and make the code more elegant. There really isn't
- * much between them in performance though, especially as locks are out of 
line.
  */
 static __always_inline void __ticket_spin_lock(arch_spinlock_t *lock)
 {
-- 
1.7.6


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