From: Tomas Hruby <tom@minix3.org>
Date: Wed, 22 Sep 2010 08:01:36 +0000 (+0000)
Subject: Remove unnecessary TLB flushes
X-Git-Tag: v3.2.0~822
X-Git-Url: http://zhaoyanbai.com/repos/%22http:/www.isc.org/icons/Bv9ARM.ch10.html?a=commitdiff_plain;h=2d1c8849d8eef83827c7f1fffa880d8256530df1;p=minix.git

Remove unnecessary TLB flushes

- this should be only for SMP
---

diff --git a/kernel/arch/i386/klib.S b/kernel/arch/i386/klib.S
index e7e7feb89..515ea5ea1 100644
--- a/kernel/arch/i386/klib.S
+++ b/kernel/arch/i386/klib.S
@@ -803,7 +803,7 @@ ENTRY(__switch_address_space)
 	 * test if the cr3 is loaded with the current value to avoid unnecessary
 	 * TLB flushes
 	 */
-#if 0
+#ifndef CONFIG_SMP
 	mov	%cr3, %ecx
 	cmp	%ecx, %eax
 	je	0f
diff --git a/kernel/proc.c b/kernel/proc.c
index a3f339917..3f541b479 100644
--- a/kernel/proc.c
+++ b/kernel/proc.c
@@ -374,7 +374,9 @@ check_misc_flags:
 	p->p_misc_flags &= ~MF_CONTEXT_SET;
 
   	assert(!(p->p_misc_flags & MF_FULLVM) || p->p_seg.p_cr3 != 0);
+#ifdef CONFIG_SMP
 	refresh_tlb();
+#endif
 	/*
 	 * restore_user_context() carries out the actual mode switch from kernel
 	 * to userspace. This function does not return