From 503595010f2024b236fd2636a7318fe64c794d6c Mon Sep 17 00:00:00 2001 From: Ian Campbell Date: Wed, 30 Jan 2008 13:33:27 +0100 Subject: [PATCH] x86_32: remove unnecessary use of %ebx as the boot cpu flag MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Currently in head_32.S there are two ways we test to see if we are the boot cpu. By looking at %ebx and by looking at the static variable ready. When changing things around I have found that it gets tricky to preserve %ebx. So this patch just switches head.S over to the more reliable test of always using ready. Hopefully later we can kill these tests entirely. Signed-off-by: Eric W. Biederman Signed-off-by: Ian Campbell Cc: H. Peter Anvin Cc: Andi Kleen Cc: Mika Penttilä Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- arch/x86/kernel/head_32.S | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S index f409fe2a52e4..7b9b2566b7a8 100644 --- a/arch/x86/kernel/head_32.S +++ b/arch/x86/kernel/head_32.S @@ -199,7 +199,6 @@ default_entry: addl $0x67, %eax /* 0x67 == _PAGE_TABLE */ movl %eax, 4092(%edx) - xorl %ebx,%ebx /* This is the boot CPU (BSP) */ jmp 3f /* * Non-boot CPU entry point; entered from trampoline.S @@ -268,10 +267,6 @@ ENTRY(startup_32_smp) wrmsr 6: - /* This is a secondary processor (AP) */ - xorl %ebx,%ebx - incl %ebx - #endif /* CONFIG_SMP */ 3: @@ -297,7 +292,7 @@ ENTRY(startup_32_smp) popfl #ifdef CONFIG_SMP - andl %ebx,%ebx + cmpb $0, ready jz 1f /* Initial CPU cleans BSS */ jmp checkCPUtype 1: -- 2.20.1