x86: unify setup_trampoline
setup_trampoline() looks very similar between architectures, and this
patch unifies them. The i386 version allocates bootmem memory, while
the x86_64 version uses a fixed address.
In this patch, we initialize the global trampoline_base to the x86_64 version,
and i386 allocation can later override it.
Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 34c3117..b13b9d5 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -3,6 +3,7 @@
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/percpu.h>
+#include <linux/bootmem.h>
#include <asm/nmi.h>
#include <asm/irq.h>
@@ -38,6 +39,9 @@
DEFINE_PER_CPU_SHARED_ALIGNED(struct cpuinfo_x86, cpu_info);
EXPORT_PER_CPU_SYMBOL(cpu_info);
+/* ready for x86_64, no harm for x86, since it will overwrite after alloc */
+unsigned char *trampoline_base = __va(SMP_TRAMPOLINE_BASE);
+
/* representing cpus for which sibling maps can be computed */
static cpumask_t cpu_sibling_setup_map;
@@ -117,6 +121,35 @@
return c->llc_shared_map;
}
+/*
+ * Currently trivial. Write the real->protected mode
+ * bootstrap into the page concerned. The caller
+ * has made sure it's suitably aligned.
+ */
+
+unsigned long __cpuinit setup_trampoline(void)
+{
+ memcpy(trampoline_base, trampoline_data,
+ trampoline_end - trampoline_data);
+ return virt_to_phys(trampoline_base);
+}
+
+#ifdef CONFIG_X86_32
+/*
+ * We are called very early to get the low memory for the
+ * SMP bootup trampoline page.
+ */
+void __init smp_alloc_memory(void)
+{
+ trampoline_base = alloc_bootmem_low_pages(PAGE_SIZE);
+ /*
+ * Has to be in very low memory so we can execute
+ * real-mode AP code.
+ */
+ if (__pa(trampoline_base) >= 0x9F000)
+ BUG();
+}
+#endif
#ifdef CONFIG_HOTPLUG_CPU
void remove_siblinginfo(int cpu)
diff --git a/arch/x86/kernel/smpboot_32.c b/arch/x86/kernel/smpboot_32.c
index a21f254..ee82659 100644
--- a/arch/x86/kernel/smpboot_32.c
+++ b/arch/x86/kernel/smpboot_32.c
@@ -73,41 +73,12 @@
u8 apicid_2_node[MAX_APICID];
-static unsigned char *trampoline_base;
-
static void map_cpu_to_logical_apicid(void);
/* State of each CPU. */
DEFINE_PER_CPU(int, cpu_state) = { 0 };
/*
- * Currently trivial. Write the real->protected mode
- * bootstrap into the page concerned. The caller
- * has made sure it's suitably aligned.
- */
-
-static unsigned long __cpuinit setup_trampoline(void)
-{
- memcpy(trampoline_base, trampoline_data, trampoline_end - trampoline_data);
- return virt_to_phys(trampoline_base);
-}
-
-/*
- * We are called very early to get the low memory for the
- * SMP bootup trampoline page.
- */
-void __init smp_alloc_memory(void)
-{
- trampoline_base = alloc_bootmem_low_pages(PAGE_SIZE);
- /*
- * Has to be in very low memory so we can execute
- * real-mode AP code.
- */
- if (__pa(trampoline_base) >= 0x9F000)
- BUG();
-}
-
-/*
* The bootstrap kernel entry code has set these up. Save them for
* a given CPU
*/
diff --git a/arch/x86/kernel/smpboot_64.c b/arch/x86/kernel/smpboot_64.c
index 2cc1b8b..9f4935e 100644
--- a/arch/x86/kernel/smpboot_64.c
+++ b/arch/x86/kernel/smpboot_64.c
@@ -85,20 +85,6 @@
#define set_idle_for_cpu(x,p) (idle_thread_array[(x)] = (p))
#endif
-
-/*
- * Currently trivial. Write the real->protected mode
- * bootstrap into the page concerned. The caller
- * has made sure it's suitably aligned.
- */
-
-static unsigned long __cpuinit setup_trampoline(void)
-{
- void *tramp = __va(SMP_TRAMPOLINE_BASE);
- memcpy(tramp, trampoline_data, trampoline_end - trampoline_data);
- return virt_to_phys(tramp);
-}
-
/*
* The bootstrap kernel entry code has set these up. Save them for
* a given CPU
diff --git a/include/asm-x86/smp.h b/include/asm-x86/smp.h
index b2a1697..513c857 100644
--- a/include/asm-x86/smp.h
+++ b/include/asm-x86/smp.h
@@ -14,6 +14,7 @@
*/
extern const unsigned char trampoline_data [];
extern const unsigned char trampoline_end [];
+extern unsigned char *trampoline_base;
struct smp_ops {
void (*smp_prepare_boot_cpu)(void);
@@ -81,6 +82,9 @@
extern unsigned disabled_cpus;
extern void prefill_possible_map(void);
+
+#define SMP_TRAMPOLINE_BASE 0x6000
+extern unsigned long setup_trampoline(void);
#endif
#ifdef CONFIG_X86_32
diff --git a/include/asm-x86/smp_64.h b/include/asm-x86/smp_64.h
index d554d7d..394c785 100644
--- a/include/asm-x86/smp_64.h
+++ b/include/asm-x86/smp_64.h
@@ -40,8 +40,6 @@
#ifdef CONFIG_SMP
-#define SMP_TRAMPOLINE_BASE 0x6000
-
#define raw_smp_processor_id() read_pda(cpunumber)
#define cpu_physical_id(cpu) per_cpu(x86_cpu_to_apicid, cpu)