smp: move smp setup functions to kernel/smp.c
Move setup_nr_cpu_ids(), smp_init() and some other SMP boot parameter
setup functions from init/main.c to kenrel/smp.c, saves some #ifdef
CONFIG_SMP.
Signed-off-by: WANG Cong <amwang@redhat.com>
Cc: Rakib Mullick <rakib.mullick@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/smp.h b/include/linux/smp.h
index 6dc95ca..48159dd 100644
--- a/include/linux/smp.h
+++ b/include/linux/smp.h
@@ -114,6 +114,8 @@
void smp_prepare_boot_cpu(void);
extern unsigned int setup_max_cpus;
+extern void __init setup_nr_cpu_ids(void);
+extern void __init smp_init(void);
#else /* !SMP */
diff --git a/init/main.c b/init/main.c
index 33c37c3..3627bb3 100644
--- a/init/main.c
+++ b/init/main.c
@@ -129,63 +129,6 @@
static char *execute_command;
static char *ramdisk_execute_command;
-#ifdef CONFIG_SMP
-/* Setup configured maximum number of CPUs to activate */
-unsigned int setup_max_cpus = NR_CPUS;
-EXPORT_SYMBOL(setup_max_cpus);
-
-
-/*
- * Setup routine for controlling SMP activation
- *
- * Command-line option of "nosmp" or "maxcpus=0" will disable SMP
- * activation entirely (the MPS table probe still happens, though).
- *
- * Command-line option of "maxcpus=<NUM>", where <NUM> is an integer
- * greater than 0, limits the maximum number of CPUs activated in
- * SMP mode to <NUM>.
- */
-
-void __weak arch_disable_smp_support(void) { }
-
-static int __init nosmp(char *str)
-{
- setup_max_cpus = 0;
- arch_disable_smp_support();
-
- return 0;
-}
-
-early_param("nosmp", nosmp);
-
-/* this is hard limit */
-static int __init nrcpus(char *str)
-{
- int nr_cpus;
-
- get_option(&str, &nr_cpus);
- if (nr_cpus > 0 && nr_cpus < nr_cpu_ids)
- nr_cpu_ids = nr_cpus;
-
- return 0;
-}
-
-early_param("nr_cpus", nrcpus);
-
-static int __init maxcpus(char *str)
-{
- get_option(&str, &setup_max_cpus);
- if (setup_max_cpus == 0)
- arch_disable_smp_support();
-
- return 0;
-}
-
-early_param("maxcpus", maxcpus);
-#else
-static const unsigned int setup_max_cpus = NR_CPUS;
-#endif
-
/*
* If set, this is an indication to the drivers that reset the underlying
* device before going ahead with the initialization otherwise driver might
@@ -362,7 +305,7 @@
__setup("rdinit=", rdinit_setup);
#ifndef CONFIG_SMP
-
+static const unsigned int setup_max_cpus = NR_CPUS;
#ifdef CONFIG_X86_LOCAL_APIC
static void __init smp_init(void)
{
@@ -374,37 +317,6 @@
static inline void setup_nr_cpu_ids(void) { }
static inline void smp_prepare_cpus(unsigned int maxcpus) { }
-
-#else
-
-/* Setup number of possible processor ids */
-int nr_cpu_ids __read_mostly = NR_CPUS;
-EXPORT_SYMBOL(nr_cpu_ids);
-
-/* An arch may set nr_cpu_ids earlier if needed, so this would be redundant */
-static void __init setup_nr_cpu_ids(void)
-{
- nr_cpu_ids = find_last_bit(cpumask_bits(cpu_possible_mask),NR_CPUS) + 1;
-}
-
-/* Called by boot processor to activate the rest. */
-static void __init smp_init(void)
-{
- unsigned int cpu;
-
- /* FIXME: This should be done in userspace --RR */
- for_each_present_cpu(cpu) {
- if (num_online_cpus() >= setup_max_cpus)
- break;
- if (!cpu_online(cpu))
- cpu_up(cpu);
- }
-
- /* Any cleanup work */
- printk(KERN_INFO "Brought up %ld CPUs\n", (long)num_online_cpus());
- smp_cpus_done(setup_max_cpus);
-}
-
#endif
/*
diff --git a/kernel/smp.c b/kernel/smp.c
index 7cbd0f2..73a1951 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -604,6 +604,87 @@
}
#endif /* USE_GENERIC_SMP_HELPERS */
+/* Setup configured maximum number of CPUs to activate */
+unsigned int setup_max_cpus = NR_CPUS;
+EXPORT_SYMBOL(setup_max_cpus);
+
+
+/*
+ * Setup routine for controlling SMP activation
+ *
+ * Command-line option of "nosmp" or "maxcpus=0" will disable SMP
+ * activation entirely (the MPS table probe still happens, though).
+ *
+ * Command-line option of "maxcpus=<NUM>", where <NUM> is an integer
+ * greater than 0, limits the maximum number of CPUs activated in
+ * SMP mode to <NUM>.
+ */
+
+void __weak arch_disable_smp_support(void) { }
+
+static int __init nosmp(char *str)
+{
+ setup_max_cpus = 0;
+ arch_disable_smp_support();
+
+ return 0;
+}
+
+early_param("nosmp", nosmp);
+
+/* this is hard limit */
+static int __init nrcpus(char *str)
+{
+ int nr_cpus;
+
+ get_option(&str, &nr_cpus);
+ if (nr_cpus > 0 && nr_cpus < nr_cpu_ids)
+ nr_cpu_ids = nr_cpus;
+
+ return 0;
+}
+
+early_param("nr_cpus", nrcpus);
+
+static int __init maxcpus(char *str)
+{
+ get_option(&str, &setup_max_cpus);
+ if (setup_max_cpus == 0)
+ arch_disable_smp_support();
+
+ return 0;
+}
+
+early_param("maxcpus", maxcpus);
+
+/* Setup number of possible processor ids */
+int nr_cpu_ids __read_mostly = NR_CPUS;
+EXPORT_SYMBOL(nr_cpu_ids);
+
+/* An arch may set nr_cpu_ids earlier if needed, so this would be redundant */
+void __init setup_nr_cpu_ids(void)
+{
+ nr_cpu_ids = find_last_bit(cpumask_bits(cpu_possible_mask),NR_CPUS) + 1;
+}
+
+/* Called by boot processor to activate the rest. */
+void __init smp_init(void)
+{
+ unsigned int cpu;
+
+ /* FIXME: This should be done in userspace --RR */
+ for_each_present_cpu(cpu) {
+ if (num_online_cpus() >= setup_max_cpus)
+ break;
+ if (!cpu_online(cpu))
+ cpu_up(cpu);
+ }
+
+ /* Any cleanup work */
+ printk(KERN_INFO "Brought up %ld CPUs\n", (long)num_online_cpus());
+ smp_cpus_done(setup_max_cpus);
+}
+
/*
* Call a function on all processors. May be used during early boot while
* early_boot_irqs_disabled is set. Use local_irq_save/restore() instead
