[PATCH] x86_64: x86_64 version of the smp alternative patch.

Changes are largely identical to the i386 version:

 * alternative #define are moved to the new alternative.h file.
 * one new elf section with pointers to the lock prefixes which can be
   nop'ed out for non-smp.
 * two new elf sections simliar to the "classic" alternatives to
   replace SMP code with simpler UP code.
 * fixup headers to use alternative.h instead of defining their own
   LOCK / LOCK_PREFIX macros.

The patch reuses the i386 version of the alternatives code to avoid code
duplication.  The code in alternatives.c was shuffled around a bit to
reduce the number of #ifdefs needed.  It also got some tweaks needed for
x86_64 (vsyscall page handling) and new features (noreplacement option
which was x86_64 only up to now).  Debug printk's are changed from
compile-time to runtime.

Loosely based on a early version from Bastian Blank <waldi@debian.org>

Signed-off-by: Gerd Hoffmann <kraxel@suse.de>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 1 insertions, 75 deletions

diff --git a/arch/x86_64/kernel/setup.c b/arch/x86_64/kernel/setup.c
index 4b7e02216970..64640c8f5eed 100644
--- a/arch/x86_64/kernel/setup.c
+++ b/arch/x86_64/kernel/setup.c
@@ -473,80 +473,6 @@ contig_initmem_init(unsigned long start_pfn, unsigned long end_pfn)
 } 
 #endif
 
-/* Use inline assembly to define this because the nops are defined 
-   as inline assembly strings in the include files and we cannot 
-   get them easily into strings. */
-asm("\t.data\nk8nops: " 
-    K8_NOP1 K8_NOP2 K8_NOP3 K8_NOP4 K8_NOP5 K8_NOP6
-    K8_NOP7 K8_NOP8); 
-    
-extern unsigned char k8nops[];
-static unsigned char *k8_nops[ASM_NOP_MAX+1] = { 
-     NULL,
-     k8nops,
-     k8nops + 1,
-     k8nops + 1 + 2,
-     k8nops + 1 + 2 + 3,
-     k8nops + 1 + 2 + 3 + 4,
-     k8nops + 1 + 2 + 3 + 4 + 5,
-     k8nops + 1 + 2 + 3 + 4 + 5 + 6,
-     k8nops + 1 + 2 + 3 + 4 + 5 + 6 + 7,
-}; 
-
-extern char __vsyscall_0;
-
-/* Replace instructions with better alternatives for this CPU type.
-
-   This runs before SMP is initialized to avoid SMP problems with
-   self modifying code. This implies that assymetric systems where
-   APs have less capabilities than the boot processor are not handled. 
-   In this case boot with "noreplacement". */ 
-void apply_alternatives(void *start, void *end) 
-{ 
-        struct alt_instr *a; 
-        int diff, i, k;
-        for (a = start; (void *)a < end; a++) { 
-                u8 *instr;
-
-                if (!boot_cpu_has(a->cpuid))
-                        continue;
-
-                BUG_ON(a->replacementlen > a->instrlen); 
-                instr = a->instr;
-                /* vsyscall code is not mapped yet. resolve it manually. */
-                if (instr >= (u8 *)VSYSCALL_START && instr < (u8*)VSYSCALL_END)
-                        instr = __va(instr - (u8*)VSYSCALL_START + (u8*)__pa_symbol(&__vsyscall_0));
-                __inline_memcpy(instr, a->replacement, a->replacementlen);
-                diff = a->instrlen - a->replacementlen; 
-
-                /* Pad the rest with nops */
-                for (i = a->replacementlen; diff > 0; diff -= k, i += k) {
-                        k = diff;
-                        if (k > ASM_NOP_MAX)
-                                k = ASM_NOP_MAX;
-                        __inline_memcpy(instr + i, k8_nops[k], k);
-                } 
-        }
-} 
-
-static int no_replacement __initdata = 0; 
- 
-void __init alternative_instructions(void)
-{
-        extern struct alt_instr __alt_instructions[], __alt_instructions_end[];
-        if (no_replacement) 
-                return;
-        apply_alternatives(__alt_instructions, __alt_instructions_end);
-}
-
-static int __init noreplacement_setup(char *s)
-{ 
-     no_replacement = 1; 
-     return 1;
-} 
-
-__setup("noreplacement", noreplacement_setup); 
-
 #if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
 struct edd edd;
 #ifdef CONFIG_EDD_MODULE
@@ -1303,7 +1229,7 @@ static int show_cpuinfo(struct seq_file *m, void *v)
                 /* Other (Linux-defined) */
                 "cxmmx", NULL, "cyrix_arr", "centaur_mcr", NULL,
                 "constant_tsc", NULL, NULL,
-                NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+                "up", NULL, NULL, NULL, NULL, NULL, NULL, NULL,
                 NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
                 NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,