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Date:      Thu, 5 Aug 2010 22:04:07 +0000 (UTC)
From:      John Baldwin <jhb@FreeBSD.org>
To:        src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-7@freebsd.org
Subject:   svn commit: r210902 - in stable/7/sys: amd64/include i386/include
Message-ID:  <201008052204.o75M47Kn018919@svn.freebsd.org>
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Author: jhb
Date: Thu Aug  5 22:04:07 2010
New Revision: 210902
URL: http://svn.freebsd.org/changeset/base/210902

Log:
  MFC 210623:
  Mark the __curthread() functions as __pure2 and remove the volatile keyword
  from the inline assembly.  This allows the compiler to cache invocations of
  curthread since it's value does not change within a thread context.

Modified:
  stable/7/sys/amd64/include/pcpu.h
  stable/7/sys/i386/include/pcpu.h
Directory Properties:
  stable/7/sys/   (props changed)
  stable/7/sys/cddl/contrib/opensolaris/   (props changed)
  stable/7/sys/contrib/dev/acpica/   (props changed)
  stable/7/sys/contrib/pf/   (props changed)

Modified: stable/7/sys/amd64/include/pcpu.h
==============================================================================
--- stable/7/sys/amd64/include/pcpu.h	Thu Aug  5 22:01:14 2010	(r210901)
+++ stable/7/sys/amd64/include/pcpu.h	Thu Aug  5 22:04:07 2010	(r210902)
@@ -188,12 +188,12 @@ extern struct pcpu *pcpup;
 #define	PCPU_PTR(member)	__PCPU_PTR(pc_ ## member)
 #define	PCPU_SET(member, val)	__PCPU_SET(pc_ ## member, val)
 
-static __inline struct thread *
+static __inline __pure2 struct thread *
 __curthread(void)
 {
 	struct thread *td;
 
-	__asm __volatile("movq %%gs:0,%0" : "=r" (td));
+	__asm("movq %%gs:0,%0" : "=r" (td));
 	return (td);
 }
 #define	curthread		(__curthread())

Modified: stable/7/sys/i386/include/pcpu.h
==============================================================================
--- stable/7/sys/i386/include/pcpu.h	Thu Aug  5 22:01:14 2010	(r210901)
+++ stable/7/sys/i386/include/pcpu.h	Thu Aug  5 22:04:07 2010	(r210902)
@@ -189,12 +189,12 @@ extern struct pcpu *pcpup;
 #define	PCPU_PTR(member)	__PCPU_PTR(pc_ ## member)
 #define	PCPU_SET(member, val)	__PCPU_SET(pc_ ## member, val)
 
-static __inline struct thread *
+static __inline __pure2 struct thread *
 __curthread(void)
 {
 	struct thread *td;
 
-	__asm __volatile("movl %%fs:0,%0" : "=r" (td));
+	__asm("movl %%fs:0,%0" : "=r" (td));
 	return (td);
 }
 #define	curthread		(__curthread())

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