Pull percpu-dtc into release branch

[pandora-kernel.git] / arch / i386 / kernel / alternative.c

diff --git a/arch/i386/kernel/alternative.c b/arch/i386/kernel/alternative.c
index 535f979..426f59b 100644 (file)
--- a/arch/i386/kernel/alternative.c
+++ b/arch/i386/kernel/alternative.c
@@ -5,15 +5,9 @@
 #include <asm/alternative.h>
 #include <asm/sections.h>
 
-static int no_replacement    = 0;
 static int smp_alt_once      = 0;
 static int debug_alternative = 0;
 
-static int __init noreplacement_setup(char *s)
-{
-       no_replacement = 1;
-       return 1;
-}
 static int __init bootonly(char *str)
 {
        smp_alt_once = 1;
@@ -25,7 +19,6 @@ static int __init debug_alt(char *str)
        return 1;
 }
 
-__setup("noreplacement", noreplacement_setup);
 __setup("smp-alt-boot", bootonly);
 __setup("debug-alternative", debug_alt);
 
@@ -124,6 +117,20 @@ static unsigned char** find_nop_table(void)
 
 #endif /* CONFIG_X86_64 */
 
+static void nop_out(void *insns, unsigned int len)
+{
+       unsigned char **noptable = find_nop_table();
+
+       while (len > 0) {
+               unsigned int noplen = len;
+               if (noplen > ASM_NOP_MAX)
+                       noplen = ASM_NOP_MAX;
+               memcpy(insns, noptable[noplen], noplen);
+               insns += noplen;
+               len -= noplen;
+       }
+}
+
 extern struct alt_instr __alt_instructions[], __alt_instructions_end[];
 extern struct alt_instr __smp_alt_instructions[], __smp_alt_instructions_end[];
 extern u8 *__smp_locks[], *__smp_locks_end[];
@@ -138,10 +145,9 @@ extern u8 __smp_alt_begin[], __smp_alt_end[];
 
 void apply_alternatives(struct alt_instr *start, struct alt_instr *end)
 {
-       unsigned char **noptable = find_nop_table();
        struct alt_instr *a;
        u8 *instr;
-       int diff, i, k;
+       int diff;
 
        DPRINTK("%s: alt table %p -> %p\n", __FUNCTION__, start, end);
        for (a = start; a < end; a++) {
@@ -159,13 +165,7 @@ void apply_alternatives(struct alt_instr *start, struct alt_instr *end)
 #endif
                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;
-                       memcpy(a->instr + i, noptable[k], k);
-               }
+               nop_out(instr + a->replacementlen, diff);
        }
 }
 
@@ -209,7 +209,6 @@ static void alternatives_smp_lock(u8 **start, u8 **end, u8 *text, u8 *text_end)
 
 static void alternatives_smp_unlock(u8 **start, u8 **end, u8 *text, u8 *text_end)
 {
-       unsigned char **noptable = find_nop_table();
        u8 **ptr;
 
        for (ptr = start; ptr < end; ptr++) {
@@ -217,7 +216,7 @@ static void alternatives_smp_unlock(u8 **start, u8 **end, u8 *text, u8 *text_end
                        continue;
                if (*ptr > text_end)
                        continue;
-               **ptr = noptable[1][0];
+               nop_out(*ptr, 1);
        };
 }
 
@@ -246,9 +245,6 @@ void alternatives_smp_module_add(struct module *mod, char *name,
        struct smp_alt_module *smp;
        unsigned long flags;
 
-       if (no_replacement)
-               return;
-
        if (smp_alt_once) {
                if (boot_cpu_has(X86_FEATURE_UP))
                        alternatives_smp_unlock(locks, locks_end,
@@ -283,7 +279,7 @@ void alternatives_smp_module_del(struct module *mod)
        struct smp_alt_module *item;
        unsigned long flags;
 
-       if (no_replacement || smp_alt_once)
+       if (smp_alt_once)
                return;
 
        spin_lock_irqsave(&smp_alt, flags);
@@ -314,7 +310,7 @@ void alternatives_smp_switch(int smp)
        return;
 #endif
 
-       if (no_replacement || smp_alt_once)
+       if (smp_alt_once)
                return;
        BUG_ON(!smp && (num_online_cpus() > 1));
 
@@ -343,16 +339,43 @@ void alternatives_smp_switch(int smp)
 
 #endif
 
+#ifdef CONFIG_PARAVIRT
+void apply_paravirt(struct paravirt_patch *start, struct paravirt_patch *end)
+{
+       struct paravirt_patch *p;
+
+       for (p = start; p < end; p++) {
+               unsigned int used;
+
+               used = paravirt_ops.patch(p->instrtype, p->clobbers, p->instr,
+                                         p->len);
+#ifdef CONFIG_DEBUG_PARAVIRT
+               {
+               int i;
+               /* Deliberately clobber regs using "not %reg" to find bugs. */
+               for (i = 0; i < 3; i++) {
+                       if (p->len - used >= 2 && (p->clobbers & (1 << i))) {
+                               memcpy(p->instr + used, "\xf7\xd0", 2);
+                               p->instr[used+1] |= i;
+                               used += 2;
+                       }
+               }
+               }
+#endif
+               /* Pad the rest with nops */
+               nop_out(p->instr + used, p->len - used);
+       }
+
+       /* Sync to be conservative, in case we patched following instructions */
+       sync_core();
+}
+extern struct paravirt_patch __start_parainstructions[],
+       __stop_parainstructions[];
+#endif /* CONFIG_PARAVIRT */
+
 void __init alternative_instructions(void)
 {
        unsigned long flags;
-       if (no_replacement) {
-               printk(KERN_INFO "(SMP-)alternatives turned off\n");
-               free_init_pages("SMP alternatives",
-                               (unsigned long)__smp_alt_begin,
-                               (unsigned long)__smp_alt_end);
-               return;
-       }
 
        local_irq_save(flags);
        apply_alternatives(__alt_instructions, __alt_instructions_end);
@@ -390,5 +413,6 @@ void __init alternative_instructions(void)
                alternatives_smp_switch(0);
        }
 #endif
+       apply_paravirt(__start_parainstructions, __stop_parainstructions);
        local_irq_restore(flags);
 }