#include <asm/pgtable.h>
#include <asm/mce.h>
#include <asm/nmi.h>
+#include <asm/vsyscall.h>
#define MAX_PATCH_LEN (255-1)
/* 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\nintelnops: "
+asm("\t.section .rodata, \"a\"\nintelnops: "
GENERIC_NOP1 GENERIC_NOP2 GENERIC_NOP3 GENERIC_NOP4 GENERIC_NOP5 GENERIC_NOP6
GENERIC_NOP7 GENERIC_NOP8);
-extern unsigned char intelnops[];
-static unsigned char *intel_nops[ASM_NOP_MAX+1] = {
+extern const unsigned char intelnops[];
+static const unsigned char *const intel_nops[ASM_NOP_MAX+1] = {
NULL,
intelnops,
intelnops + 1,
#endif
#ifdef K8_NOP1
-asm("\t.data\nk8nops: "
+asm("\t.section .rodata, \"a\"\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] = {
+extern const unsigned char k8nops[];
+static const unsigned char *const k8_nops[ASM_NOP_MAX+1] = {
NULL,
k8nops,
k8nops + 1,
#endif
#ifdef K7_NOP1
-asm("\t.data\nk7nops: "
+asm("\t.section .rodata, \"a\"\nk7nops: "
K7_NOP1 K7_NOP2 K7_NOP3 K7_NOP4 K7_NOP5 K7_NOP6
K7_NOP7 K7_NOP8);
-extern unsigned char k7nops[];
-static unsigned char *k7_nops[ASM_NOP_MAX+1] = {
+extern const unsigned char k7nops[];
+static const unsigned char *const k7_nops[ASM_NOP_MAX+1] = {
NULL,
k7nops,
k7nops + 1,
};
#endif
+#ifdef P6_NOP1
+asm("\t.section .rodata, \"a\"\np6nops: "
+ P6_NOP1 P6_NOP2 P6_NOP3 P6_NOP4 P6_NOP5 P6_NOP6
+ P6_NOP7 P6_NOP8);
+extern const unsigned char p6nops[];
+static const unsigned char *const p6_nops[ASM_NOP_MAX+1] = {
+ NULL,
+ p6nops,
+ p6nops + 1,
+ p6nops + 1 + 2,
+ p6nops + 1 + 2 + 3,
+ p6nops + 1 + 2 + 3 + 4,
+ p6nops + 1 + 2 + 3 + 4 + 5,
+ p6nops + 1 + 2 + 3 + 4 + 5 + 6,
+ p6nops + 1 + 2 + 3 + 4 + 5 + 6 + 7,
+};
+#endif
+
#ifdef CONFIG_X86_64
extern char __vsyscall_0;
-static inline unsigned char** find_nop_table(void)
+static inline const unsigned char*const * find_nop_table(void)
{
- return k8_nops;
+ return boot_cpu_data.x86_vendor != X86_VENDOR_INTEL ||
+ boot_cpu_data.x86 < 6 ? k8_nops : p6_nops;
}
#else /* CONFIG_X86_64 */
-static struct nop {
+static const struct nop {
int cpuid;
- unsigned char **noptable;
+ const unsigned char *const *noptable;
} noptypes[] = {
{ X86_FEATURE_K8, k8_nops },
{ X86_FEATURE_K7, k7_nops },
+ { X86_FEATURE_P4, p6_nops },
+ { X86_FEATURE_P3, p6_nops },
{ -1, NULL }
};
-static unsigned char** find_nop_table(void)
+static const unsigned char*const * find_nop_table(void)
{
- unsigned char **noptable = intel_nops;
+ const unsigned char *const *noptable = intel_nops;
int i;
for (i = 0; noptypes[i].cpuid >= 0; i++) {
/* Use this to add nops to a buffer, then text_poke the whole buffer. */
static void add_nops(void *insns, unsigned int len)
{
- unsigned char **noptable = find_nop_table();
+ const unsigned char *const *noptable = find_nop_table();
while (len > 0) {
unsigned int noplen = len;
};
static LIST_HEAD(smp_alt_modules);
static DEFINE_SPINLOCK(smp_alt);
+static int smp_mode = 1; /* protected by smp_alt */
void alternatives_smp_module_add(struct module *mod, char *name,
void *locks, void *locks_end,
#ifdef CONFIG_LOCKDEP
/*
- * A not yet fixed binutils section handling bug prevents
- * alternatives-replacement from working reliably, so turn
- * it off:
+ * Older binutils section handling bug prevented
+ * alternatives-replacement from working reliably.
+ *
+ * If this still occurs then you should see a hang
+ * or crash shortly after this line:
*/
- printk("lockdep: not fixing up alternatives.\n");
- return;
+ printk("lockdep: fixing up alternatives.\n");
#endif
if (noreplace_smp || smp_alt_once)
BUG_ON(!smp && (num_online_cpus() > 1));
spin_lock_irqsave(&smp_alt, flags);
- if (smp) {
+
+ /*
+ * Avoid unnecessary switches because it forces JIT based VMs to
+ * throw away all cached translations, which can be quite costly.
+ */
+ if (smp == smp_mode) {
+ /* nothing */
+ } else if (smp) {
printk(KERN_INFO "SMP alternatives: switching to SMP code\n");
- clear_bit(X86_FEATURE_UP, boot_cpu_data.x86_capability);
- clear_bit(X86_FEATURE_UP, cpu_data[0].x86_capability);
+ clear_cpu_cap(&boot_cpu_data, X86_FEATURE_UP);
+ clear_cpu_cap(&cpu_data(0), X86_FEATURE_UP);
list_for_each_entry(mod, &smp_alt_modules, next)
alternatives_smp_lock(mod->locks, mod->locks_end,
mod->text, mod->text_end);
} else {
printk(KERN_INFO "SMP alternatives: switching to UP code\n");
- set_bit(X86_FEATURE_UP, boot_cpu_data.x86_capability);
- set_bit(X86_FEATURE_UP, cpu_data[0].x86_capability);
+ set_cpu_cap(&boot_cpu_data, X86_FEATURE_UP);
+ set_cpu_cap(&cpu_data(0), X86_FEATURE_UP);
list_for_each_entry(mod, &smp_alt_modules, next)
alternatives_smp_unlock(mod->locks, mod->locks_end,
mod->text, mod->text_end);
}
+ smp_mode = smp;
spin_unlock_irqrestore(&smp_alt, flags);
}
if (smp_alt_once) {
if (1 == num_possible_cpus()) {
printk(KERN_INFO "SMP alternatives: switching to UP code\n");
- set_bit(X86_FEATURE_UP, boot_cpu_data.x86_capability);
- set_bit(X86_FEATURE_UP, cpu_data[0].x86_capability);
+ set_cpu_cap(&boot_cpu_data, X86_FEATURE_UP);
+ set_cpu_cap(&cpu_data(0), X86_FEATURE_UP);
+
alternatives_smp_unlock(__smp_locks, __smp_locks_end,
_text, _etext);
}
- free_init_pages("SMP alternatives",
- (unsigned long)__smp_locks,
- (unsigned long)__smp_locks_end);
} else {
alternatives_smp_module_add(NULL, "core kernel",
__smp_locks, __smp_locks_end,
_text, _etext);
- alternatives_smp_switch(0);
+
+ /* Only switch to UP mode if we don't immediately boot others */
+ if (num_possible_cpus() == 1 || setup_max_cpus <= 1)
+ alternatives_smp_switch(0);
}
#endif
apply_paravirt(__parainstructions, __parainstructions_end);
local_irq_restore(flags);
+ if (smp_alt_once)
+ free_init_pages("SMP alternatives",
+ (unsigned long)__smp_locks,
+ (unsigned long)__smp_locks_end);
+
restart_nmi();
#ifdef CONFIG_X86_MCE
restart_mce();
projects / linux-2.6-omap-h63xx.git / blobdiff