[PATCH 02/12] i386 head.S: Remove unnecessary use of %ebx as the boot cpu flag

From: Eric W. Biederman
Date: Mon Apr 30 2007 - 11:52:18 EST



Currently in head.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 <ebiederm@xxxxxxxxxxxx>
---
arch/i386/kernel/head.S | 7 +------
1 files changed, 1 insertions(+), 6 deletions(-)

diff --git a/arch/i386/kernel/head.S b/arch/i386/kernel/head.S
index 9b10af6..aa9e28e 100644
--- a/arch/i386/kernel/head.S
+++ b/arch/i386/kernel/head.S
@@ -157,7 +157,6 @@ page_pde_offset = (__PAGE_OFFSET >> 20);
jb 10b
movl %edi,(init_pg_tables_end - __PAGE_OFFSET)

- xorl %ebx,%ebx /* This is the boot CPU (BSP) */
jmp 3f
/*
* Non-boot CPU entry point; entered from trampoline.S
@@ -228,10 +227,6 @@ ENTRY(startup_32_smp)
wrmsr

6:
- /* This is a secondary processor (AP) */
- xorl %ebx,%ebx
- incl %ebx
-
#endif /* CONFIG_SMP */
3:

@@ -257,7 +252,7 @@ ENTRY(startup_32_smp)
popfl

#ifdef CONFIG_SMP
- andl %ebx,%ebx
+ cmpb $0, ready
jz 1f /* Initial CPU cleans BSS */
jmp checkCPUtype
1:
--
1.5.1.1.181.g2de0

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