kernel: delete __cpuinit usage from all core kernel files

The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications. For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out. Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

This removes all the uses of the __cpuinit macros from C files in
the core kernel directories (kernel, init, lib, mm, and include)
that don't really have a specific maintainer.

[1] https://lkml.org/lkml/2013/5/20/589

Signed-off-by: Paul Gortmaker <[e-mail]>

Documentation/cpu-hotplug.txt

···
 A: This is what you would need in your kernel code to receive notifications.
 
 	#include <linux/cpu.h>
-	static int __cpuinit foobar_cpu_callback(struct notifier_block *nfb,
-					    unsigned long action, void *hcpu)
+	static int foobar_cpu_callback(struct notifier_block *nfb,
+				       unsigned long action, void *hcpu)
 	{
 		unsigned int cpu = (unsigned long)hcpu;
 
···
 		return NOTIFY_OK;
 	}
 
-	static struct notifier_block __cpuinitdata foobar_cpu_notifer =
+	static struct notifier_block foobar_cpu_notifer =
 	{
 	   .notifier_call = foobar_cpu_callback,
 	};

include/linux/cpu.h

···
 /* Need to know about CPUs going up/down? */
 #if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE)
 #define cpu_notifier(fn, pri) {					\
-	static struct notifier_block fn##_nb __cpuinitdata =	\
+	static struct notifier_block fn##_nb =			\
 		{ .notifier_call = fn, .priority = pri };	\
 	register_cpu_notifier(&fn##_nb);			\
 }

include/linux/perf_event.h

···
  */
 #define perf_cpu_notifier(fn)						\
 do {									\
-	static struct notifier_block fn##_nb __cpuinitdata =		\
+	static struct notifier_block fn##_nb =				\
 		{ .notifier_call = fn, .priority = CPU_PRI_PERF };	\
 	unsigned long cpu = smp_processor_id();				\
 	unsigned long flags;						\

init/calibrate.c

···
 #define DELAY_CALIBRATION_TICKS			((HZ < 100) ? 1 : (HZ/100))
 #define MAX_DIRECT_CALIBRATION_RETRIES		5
 
-static unsigned long __cpuinit calibrate_delay_direct(void)
+static unsigned long calibrate_delay_direct(void)
 {
 	unsigned long pre_start, start, post_start;
 	unsigned long pre_end, end, post_end;
···
 	return 0;
 }
 #else
-static unsigned long __cpuinit calibrate_delay_direct(void) {return 0;}
+static unsigned long calibrate_delay_direct(void)
+{
+	return 0;
+}
 #endif
 
 /*
···
  */
 #define LPS_PREC 8
 
-static unsigned long __cpuinit calibrate_delay_converge(void)
+static unsigned long calibrate_delay_converge(void)
 {
 	/* First stage - slowly accelerate to find initial bounds */
 	unsigned long lpj, lpj_base, ticks, loopadd, loopadd_base, chop_limit;
···
  * Architectures should override this function if a faster calibration
  * method is available.
  */
-unsigned long __attribute__((weak)) __cpuinit calibrate_delay_is_known(void)
+unsigned long __attribute__((weak)) calibrate_delay_is_known(void)
 {
 	return 0;
 }
 
-void __cpuinit calibrate_delay(void)
+void calibrate_delay(void)
 {
 	unsigned long lpj;
 	static bool printed;

kernel/cpu.c

···
 #endif /*CONFIG_HOTPLUG_CPU*/
 
 /* Requires cpu_add_remove_lock to be held */
-static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen)
+static int _cpu_up(unsigned int cpu, int tasks_frozen)
 {
 	int ret, nr_calls = 0;
 	void *hcpu = (void *)(long)cpu;
···
 	return ret;
 }
 
-int __cpuinit cpu_up(unsigned int cpu)
+int cpu_up(unsigned int cpu)
 {
 	int err = 0;
 
···
  * It must be called by the arch code on the new cpu, before the new cpu
  * enables interrupts and before the "boot" cpu returns from __cpu_up().
  */
-void __cpuinit notify_cpu_starting(unsigned int cpu)
+void notify_cpu_starting(unsigned int cpu)
 {
 	unsigned long val = CPU_STARTING;
 

kernel/events/core.c

···
 	}
 }
 
-static void __cpuinit perf_event_init_cpu(int cpu)
+static void perf_event_init_cpu(int cpu)
 {
 	struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu);
 
···
 	.priority = INT_MIN,
 };
 
-static int __cpuinit
+static int
 perf_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu)
 {
 	unsigned int cpu = (long)hcpu;

kernel/fork.c

···
 	}
 }
 
-struct task_struct * __cpuinit fork_idle(int cpu)
+struct task_struct *fork_idle(int cpu)
 {
 	struct task_struct *task;
 	task = copy_process(CLONE_VM, 0, 0, NULL, &init_struct_pid, 0);

kernel/hrtimer.c

···
 /*
  * Functions related to boot-time initialization:
  */
-static void __cpuinit init_hrtimers_cpu(int cpu)
+static void init_hrtimers_cpu(int cpu)
 {
 	struct hrtimer_cpu_base *cpu_base = &per_cpu(hrtimer_bases, cpu);
 	int i;
···
 
 #endif /* CONFIG_HOTPLUG_CPU */
 
-static int __cpuinit hrtimer_cpu_notify(struct notifier_block *self,
+static int hrtimer_cpu_notify(struct notifier_block *self,
 					unsigned long action, void *hcpu)
 {
 	int scpu = (long)hcpu;
···
 	return NOTIFY_OK;
 }
 
-static struct notifier_block __cpuinitdata hrtimers_nb = {
+static struct notifier_block hrtimers_nb = {
 	.notifier_call = hrtimer_cpu_notify,
 };
 

kernel/printk.c

···
  * called when a new CPU comes online (or fails to come up), and ensures
  * that any such output gets printed.
  */
-static int __cpuinit console_cpu_notify(struct notifier_block *self,
+static int console_cpu_notify(struct notifier_block *self,
 	unsigned long action, void *hcpu)
 {
 	switch (action) {

kernel/profile.c

···
 	put_cpu();
 }
 
-static int __cpuinit profile_cpu_callback(struct notifier_block *info,
+static int profile_cpu_callback(struct notifier_block *info,
 					unsigned long action, void *__cpu)
 {
 	int node, cpu = (unsigned long)__cpu;

kernel/relay.c

···
  *
  * 	Returns the success/failure of the operation. (%NOTIFY_OK, %NOTIFY_BAD)
  */
-static int __cpuinit relay_hotcpu_callback(struct notifier_block *nb,
+static int relay_hotcpu_callback(struct notifier_block *nb,
 				unsigned long action,
 				void *hcpu)
 {

kernel/sched/core.c

···
 		debug_show_all_locks();
 }
 
-void __cpuinit init_idle_bootup_task(struct task_struct *idle)
+void init_idle_bootup_task(struct task_struct *idle)
 {
 	idle->sched_class = &idle_sched_class;
 }
···
  * NOTE: this function does not set the idle thread's NEED_RESCHED
  * flag, to make booting more robust.
  */
-void __cpuinit init_idle(struct task_struct *idle, int cpu)
+void init_idle(struct task_struct *idle, int cpu)
 {
 	struct rq *rq = cpu_rq(cpu);
 	unsigned long flags;
···
  * migration_call - callback that gets triggered when a CPU is added.
  * Here we can start up the necessary migration thread for the new CPU.
  */
-static int __cpuinit
+static int
 migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
 {
 	int cpu = (long)hcpu;
···
  * happens before everything else.  This has to be lower priority than
  * the notifier in the perf_event subsystem, though.
  */
-static struct notifier_block __cpuinitdata migration_notifier = {
+static struct notifier_block migration_notifier = {
 	.notifier_call = migration_call,
 	.priority = CPU_PRI_MIGRATION,
 };
 
-static int __cpuinit sched_cpu_active(struct notifier_block *nfb,
+static int sched_cpu_active(struct notifier_block *nfb,
 				      unsigned long action, void *hcpu)
 {
 	switch (action & ~CPU_TASKS_FROZEN) {
···
 	}
 }
 
-static int __cpuinit sched_cpu_inactive(struct notifier_block *nfb,
+static int sched_cpu_inactive(struct notifier_block *nfb,
 					unsigned long action, void *hcpu)
 {
 	switch (action & ~CPU_TASKS_FROZEN) {

kernel/sched/fair.c

···
 	set_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu));
 }
 
-static int __cpuinit sched_ilb_notifier(struct notifier_block *nfb,
+static int sched_ilb_notifier(struct notifier_block *nfb,
 					unsigned long action, void *hcpu)
 {
 	switch (action & ~CPU_TASKS_FROZEN) {

kernel/smp.c

···
 	return NOTIFY_OK;
 }
 
-static struct notifier_block __cpuinitdata hotplug_cfd_notifier = {
+static struct notifier_block hotplug_cfd_notifier = {
 	.notifier_call		= hotplug_cfd,
 };
 

kernel/smpboot.c

···
  */
 static DEFINE_PER_CPU(struct task_struct *, idle_threads);
 
-struct task_struct * __cpuinit idle_thread_get(unsigned int cpu)
+struct task_struct *idle_thread_get(unsigned int cpu)
 {
 	struct task_struct *tsk = per_cpu(idle_threads, cpu);
 

kernel/softirq.c

···
 }
 EXPORT_SYMBOL(send_remote_softirq);
 
-static int __cpuinit remote_softirq_cpu_notify(struct notifier_block *self,
+static int remote_softirq_cpu_notify(struct notifier_block *self,
 					       unsigned long action, void *hcpu)
 {
 	/*
···
 	return NOTIFY_OK;
 }
 
-static struct notifier_block __cpuinitdata remote_softirq_cpu_notifier = {
+static struct notifier_block remote_softirq_cpu_notifier = {
 	.notifier_call	= remote_softirq_cpu_notify,
 };
 
···
 }
 #endif /* CONFIG_HOTPLUG_CPU */
 
-static int __cpuinit cpu_callback(struct notifier_block *nfb,
+static int cpu_callback(struct notifier_block *nfb,
 				  unsigned long action,
 				  void *hcpu)
 {
···
 	return NOTIFY_OK;
 }
 
-static struct notifier_block __cpuinitdata cpu_nfb = {
+static struct notifier_block cpu_nfb = {
 	.notifier_call = cpu_callback
 };
 

kernel/time/tick-sched.c

···
 }
 __setup("nohz_full=", tick_nohz_full_setup);
 
-static int __cpuinit tick_nohz_cpu_down_callback(struct notifier_block *nfb,
+static int tick_nohz_cpu_down_callback(struct notifier_block *nfb,
 						 unsigned long action,
 						 void *hcpu)
 {

kernel/timer.c

···
 }
 EXPORT_SYMBOL(schedule_timeout_uninterruptible);
 
-static int __cpuinit init_timers_cpu(int cpu)
+static int init_timers_cpu(int cpu)
 {
 	int j;
 	struct tvec_base *base;
-	static char __cpuinitdata tvec_base_done[NR_CPUS];
+	static char tvec_base_done[NR_CPUS];
 
 	if (!tvec_base_done[cpu]) {
 		static char boot_done;
···
 	}
 }
 
-static void __cpuinit migrate_timers(int cpu)
+static void migrate_timers(int cpu)
 {
 	struct tvec_base *old_base;
 	struct tvec_base *new_base;
···
 }
 #endif /* CONFIG_HOTPLUG_CPU */
 
-static int __cpuinit timer_cpu_notify(struct notifier_block *self,
+static int timer_cpu_notify(struct notifier_block *self,
 				unsigned long action, void *hcpu)
 {
 	long cpu = (long)hcpu;
···
 	return NOTIFY_OK;
 }
 
-static struct notifier_block __cpuinitdata timers_nb = {
+static struct notifier_block timers_nb = {
 	.notifier_call	= timer_cpu_notify,
 };
 

kernel/workqueue.c

···
  * Workqueues should be brought up before normal priority CPU notifiers.
  * This will be registered high priority CPU notifier.
  */
-static int __cpuinit workqueue_cpu_up_callback(struct notifier_block *nfb,
+static int workqueue_cpu_up_callback(struct notifier_block *nfb,
 					       unsigned long action,
 					       void *hcpu)
 {
···
  * Workqueues should be brought down after normal priority CPU notifiers.
  * This will be registered as low priority CPU notifier.
  */
-static int __cpuinit workqueue_cpu_down_callback(struct notifier_block *nfb,
+static int workqueue_cpu_down_callback(struct notifier_block *nfb,
 						 unsigned long action,
 						 void *hcpu)
 {

lib/Kconfig.debug

···
 	  any use of code/data previously in these sections would
 	  most likely result in an oops.
 	  In the code, functions and variables are annotated with
-	  __init, __cpuinit, etc. (see the full list in include/linux/init.h),
+	  __init,, etc. (see the full list in include/linux/init.h),
 	  which results in the code/data being placed in specific sections.
 	  The section mismatch analysis is always performed after a full
 	  kernel build, and enabling this option causes the following

lib/earlycpio.c

···
  *          the match returned an empty filename string.
  */
 
-struct cpio_data __cpuinit find_cpio_data(const char *path, void *data,
+struct cpio_data find_cpio_data(const char *path, void *data,
 					  size_t len,  long *offset)
 {
 	const size_t cpio_header_len = 8*C_NFIELDS - 2;

lib/percpu_counter.c

···
 	percpu_counter_batch = max(32, nr*2);
 }
 
-static int __cpuinit percpu_counter_hotcpu_callback(struct notifier_block *nb,
+static int percpu_counter_hotcpu_callback(struct notifier_block *nb,
 					unsigned long action, void *hcpu)
 {
 #ifdef CONFIG_HOTPLUG_CPU

mm/memcontrol.c

···
 	spin_unlock(&memcg->pcp_counter_lock);
 }
 
-static int __cpuinit memcg_cpu_hotplug_callback(struct notifier_block *nb,
+static int memcg_cpu_hotplug_callback(struct notifier_block *nb,
 					unsigned long action,
 					void *hcpu)
 {

mm/page-writeback.c

···
 		ratelimit_pages = 16;
 }
 
-static int __cpuinit
+static int
 ratelimit_handler(struct notifier_block *self, unsigned long action,
 		  void *hcpu)
 {
···
 	}
 }
 
-static struct notifier_block __cpuinitdata ratelimit_nb = {
+static struct notifier_block ratelimit_nb = {
 	.notifier_call	= ratelimit_handler,
 	.next		= NULL,
 };

mm/slab.c

···
  * the CPUs getting into lockstep and contending for the global cache chain
  * lock.
  */
-static void __cpuinit start_cpu_timer(int cpu)
+static void start_cpu_timer(int cpu)
 {
 	struct delayed_work *reap_work = &per_cpu(slab_reap_work, cpu);
 
···
 	return (n->free_objects + cachep->num - 1) / cachep->num;
 }
 
-static void __cpuinit cpuup_canceled(long cpu)
+static void cpuup_canceled(long cpu)
 {
 	struct kmem_cache *cachep;
 	struct kmem_cache_node *n = NULL;
···
 	}
 }
 
-static int __cpuinit cpuup_prepare(long cpu)
+static int cpuup_prepare(long cpu)
 {
 	struct kmem_cache *cachep;
 	struct kmem_cache_node *n = NULL;
···
 	return -ENOMEM;
 }
 
-static int __cpuinit cpuup_callback(struct notifier_block *nfb,
+static int cpuup_callback(struct notifier_block *nfb,
 				    unsigned long action, void *hcpu)
 {
 	long cpu = (long)hcpu;
···
 	return notifier_from_errno(err);
 }
 
-static struct notifier_block __cpuinitdata cpucache_notifier = {
+static struct notifier_block cpucache_notifier = {
 	&cpuup_callback, NULL, 0
 };
 

mm/slub.c

···
  * Use the cpu notifier to insure that the cpu slabs are flushed when
  * necessary.
  */
-static int __cpuinit slab_cpuup_callback(struct notifier_block *nfb,
+static int slab_cpuup_callback(struct notifier_block *nfb,
 		unsigned long action, void *hcpu)
 {
 	long cpu = (long)hcpu;
···
 	return NOTIFY_OK;
 }
 
-static struct notifier_block __cpuinitdata slab_notifier = {
+static struct notifier_block slab_notifier = {
 	.notifier_call = slab_cpuup_callback
 };
 

mm/vmstat.c

···
 		round_jiffies_relative(sysctl_stat_interval));
 }
 
-static void __cpuinit start_cpu_timer(int cpu)
+static void start_cpu_timer(int cpu)
 {
 	struct delayed_work *work = &per_cpu(vmstat_work, cpu);
 
···
  * Use the cpu notifier to insure that the thresholds are recalculated
  * when necessary.
  */
-static int __cpuinit vmstat_cpuup_callback(struct notifier_block *nfb,
+static int vmstat_cpuup_callback(struct notifier_block *nfb,
 		unsigned long action,
 		void *hcpu)
 {
···
 	return NOTIFY_OK;
 }
 
-static struct notifier_block __cpuinitdata vmstat_notifier =
+static struct notifier_block vmstat_notifier =
 	{ &vmstat_cpuup_callback, NULL, 0 };
 #endif