Merge tag 'init_task-20180117' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull init_task initializer cleanups from David Howells:
 "It doesn't seem useful to have the init_task in a header file rather
  than in a normal source file. We could consolidate init_task handling
  instead and expand out various macros.

  Here's a series of patches that consolidate init_task handling:

   (1) Make THREAD_SIZE available to vmlinux.lds for cris, hexagon and
       openrisc.

   (2) Alter the INIT_TASK_DATA linker script macro to set
       init_thread_union and init_stack rather than defining these in C.

       Insert init_task and init_thread_into into the init_stack area in
       the linker script as appropriate to the configuration, with
       different section markers so that they end up correctly ordered.

       We can then get merge ia64's init_task.c into the main one.

       We then have a bunch of single-use INIT_*() macros that seem only
       to be macros because they used to be used per-arch. We can then
       expand these in place of the user and get rid of a few lines and
       a lot of backslashes.

   (3) Expand INIT_TASK() in place.

   (4) Expand in place various small INIT_*() macros that are defined
       conditionally. Expand them and surround them by #if[n]def/#endif
       in the .c file as it takes fewer lines.

   (5) Expand INIT_SIGNALS() and INIT_SIGHAND() in place.

   (6) Expand INIT_STRUCT_PID in place.

  These macros can then be discarded"

* tag 'init_task-20180117' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  Expand INIT_STRUCT_PID and remove
  Expand the INIT_SIGNALS and INIT_SIGHAND macros and remove
  Expand various INIT_* macros and remove
  Expand INIT_TASK() in init/init_task.c and remove
  Construct init thread stack in the linker script rather than by union
  openrisc: Make THREAD_SIZE available to vmlinux.lds
  hexagon: Make THREAD_SIZE available to vmlinux.lds
  cris: Make THREAD_SIZE available to vmlinux.lds

6 files changed, 23 insertions, 265 deletions

diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index ee8b707d9fa9..a564b83bf013 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -268,7 +268,11 @@
 #define INIT_TASK_DATA(align)						\
 	. = ALIGN(align);						\
 	VMLINUX_SYMBOL(__start_init_task) = .;				\
+	VMLINUX_SYMBOL(init_thread_union) = .;				\
+	VMLINUX_SYMBOL(init_stack) = .;					\
 	*(.data..init_task)						\
+	*(.data..init_thread_info)					\
+	. = VMLINUX_SYMBOL(__start_init_task) + THREAD_SIZE;		\
 	VMLINUX_SYMBOL(__end_init_task) = .;
 
 /*
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index 3319df9727aa..9c3c9a319e48 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -766,9 +766,6 @@ typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 
-/* for init task */
-#define INIT_FTRACE_GRAPH		.ret_stack = NULL,
-
 /*
  * Stack of return addresses for functions
  * of a thread.
@@ -846,7 +843,6 @@ static inline void unpause_graph_tracing(void)
 #else /* !CONFIG_FUNCTION_GRAPH_TRACER */
 
 #define __notrace_funcgraph
-#define INIT_FTRACE_GRAPH
 
 static inline void ftrace_graph_init_task(struct task_struct *t) { }
 static inline void ftrace_graph_exit_task(struct task_struct *t) { }
@@ -925,10 +921,6 @@ extern int tracepoint_printk;
 extern void disable_trace_on_warning(void);
 extern int __disable_trace_on_warning;
 
-#ifdef CONFIG_PREEMPT
-#define INIT_TRACE_RECURSION		.trace_recursion = 0,
-#endif
-
 int tracepoint_printk_sysctl(struct ctl_table *table, int write,
 			     void __user *buffer, size_t *lenp,
 			     loff_t *ppos);
@@ -937,10 +929,6 @@ int tracepoint_printk_sysctl(struct ctl_table *table, int write,
 static inline void  disable_trace_on_warning(void) { }
 #endif /* CONFIG_TRACING */
 
-#ifndef INIT_TRACE_RECURSION
-#define INIT_TRACE_RECURSION
-#endif
-
 #ifdef CONFIG_FTRACE_SYSCALLS
 
 unsigned long arch_syscall_addr(int nr);
diff --git a/include/linux/init_task.h b/include/linux/init_task.h
index 6a532629c983..a454b8aeb938 100644
--- a/include/linux/init_task.h
+++ b/include/linux/init_task.h
@@ -21,22 +21,11 @@
 
 #include <asm/thread_info.h>
 
-#ifdef CONFIG_SMP
-# define INIT_PUSHABLE_TASKS(tsk)					\
-	.pushable_tasks = PLIST_NODE_INIT(tsk.pushable_tasks, MAX_PRIO),
-#else
-# define INIT_PUSHABLE_TASKS(tsk)
-#endif
-
 extern struct files_struct init_files;
 extern struct fs_struct init_fs;
-
-#ifdef CONFIG_CPUSETS
-#define INIT_CPUSET_SEQ(tsk)							\
-	.mems_allowed_seq = SEQCNT_ZERO(tsk.mems_allowed_seq),
-#else
-#define INIT_CPUSET_SEQ(tsk)
-#endif
+extern struct nsproxy init_nsproxy;
+extern struct group_info init_groups;
+extern struct cred init_cred;
 
 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
 #define INIT_PREV_CPUTIME(x)	.prev_cputime = {			\
@@ -47,67 +36,16 @@ extern struct fs_struct init_fs;
 #endif
 
 #ifdef CONFIG_POSIX_TIMERS
-#define INIT_POSIX_TIMERS(s)						\
-	.posix_timers = LIST_HEAD_INIT(s.posix_timers),
 #define INIT_CPU_TIMERS(s)						\
 	.cpu_timers = {							\
 		LIST_HEAD_INIT(s.cpu_timers[0]),			\
 		LIST_HEAD_INIT(s.cpu_timers[1]),			\
-		LIST_HEAD_INIT(s.cpu_timers[2]),								\
-	},
-#define INIT_CPUTIMER(s)						\
-	.cputimer	= { 						\
-		.cputime_atomic	= INIT_CPUTIME_ATOMIC,			\
-		.running	= false,				\
-		.checking_timer = false,				\
+		LIST_HEAD_INIT(s.cpu_timers[2]),			\
 	},
 #else
-#define INIT_POSIX_TIMERS(s)
 #define INIT_CPU_TIMERS(s)
-#define INIT_CPUTIMER(s)
 #endif
 
-#define INIT_SIGNALS(sig) {						\
-	.nr_threads	= 1,						\
-	.thread_head	= LIST_HEAD_INIT(init_task.thread_node),	\
-	.wait_chldexit	= __WAIT_QUEUE_HEAD_INITIALIZER(sig.wait_chldexit),\
-	.shared_pending	= { 						\
-		.list = LIST_HEAD_INIT(sig.shared_pending.list),	\
-		.signal =  {{0}}},					\
-	INIT_POSIX_TIMERS(sig)						\
-	INIT_CPU_TIMERS(sig)						\
-	.rlim		= INIT_RLIMITS,					\
-	INIT_CPUTIMER(sig)						\
-	INIT_PREV_CPUTIME(sig)						\
-	.cred_guard_mutex =						\
-		 __MUTEX_INITIALIZER(sig.cred_guard_mutex),		\
-}
-
-extern struct nsproxy init_nsproxy;
-
-#define INIT_SIGHAND(sighand) {						\
-	.count		= ATOMIC_INIT(1), 				\
-	.action		= { { { .sa_handler = SIG_DFL, } }, },		\
-	.siglock	= __SPIN_LOCK_UNLOCKED(sighand.siglock),	\
-	.signalfd_wqh	= __WAIT_QUEUE_HEAD_INITIALIZER(sighand.signalfd_wqh),	\
-}
-
-extern struct group_info init_groups;
-
-#define INIT_STRUCT_PID {						\
-	.count 		= ATOMIC_INIT(1),				\
-	.tasks		= {						\
-		{ .first = NULL },					\
-		{ .first = NULL },					\
-		{ .first = NULL },					\
-	},								\
-	.level		= 0,						\
-	.numbers	= { {						\
-		.nr		= 0,					\
-		.ns		= &init_pid_ns,				\
-	}, }								\
-}
-
 #define INIT_PID_LINK(type) 					\
 {								\
 	.node = {						\
@@ -117,192 +55,16 @@ extern struct group_info init_groups;
 	.pid = &init_struct_pid,				\
 }
 
-#ifdef CONFIG_AUDITSYSCALL
-#define INIT_IDS \
-	.loginuid = INVALID_UID, \
-	.sessionid = (unsigned int)-1,
-#else
-#define INIT_IDS
-#endif
-
-#ifdef CONFIG_PREEMPT_RCU
-#define INIT_TASK_RCU_PREEMPT(tsk)					\
-	.rcu_read_lock_nesting = 0,					\
-	.rcu_read_unlock_special.s = 0,					\
-	.rcu_node_entry = LIST_HEAD_INIT(tsk.rcu_node_entry),		\
-	.rcu_blocked_node = NULL,
-#else
-#define INIT_TASK_RCU_PREEMPT(tsk)
-#endif
-#ifdef CONFIG_TASKS_RCU
-#define INIT_TASK_RCU_TASKS(tsk)					\
-	.rcu_tasks_holdout = false,					\
-	.rcu_tasks_holdout_list =					\
-		LIST_HEAD_INIT(tsk.rcu_tasks_holdout_list),		\
-	.rcu_tasks_idle_cpu = -1,
-#else
-#define INIT_TASK_RCU_TASKS(tsk)
-#endif
-
-extern struct cred init_cred;
-
-#ifdef CONFIG_CGROUP_SCHED
-# define INIT_CGROUP_SCHED(tsk)						\
-	.sched_task_group = &root_task_group,
-#else
-# define INIT_CGROUP_SCHED(tsk)
-#endif
-
-#ifdef CONFIG_PERF_EVENTS
-# define INIT_PERF_EVENTS(tsk)						\
-	.perf_event_mutex = 						\
-		 __MUTEX_INITIALIZER(tsk.perf_event_mutex),		\
-	.perf_event_list = LIST_HEAD_INIT(tsk.perf_event_list),
-#else
-# define INIT_PERF_EVENTS(tsk)
-#endif
-
-#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
-# define INIT_VTIME(tsk)						\
-	.vtime.seqcount = SEQCNT_ZERO(tsk.vtime.seqcount),		\
-	.vtime.starttime = 0,						\
-	.vtime.state = VTIME_SYS,
-#else
-# define INIT_VTIME(tsk)
-#endif
-
 #define INIT_TASK_COMM "swapper"
 
-#ifdef CONFIG_RT_MUTEXES
-# define INIT_RT_MUTEXES(tsk)						\
-	.pi_waiters = RB_ROOT_CACHED,					\
-	.pi_top_task = NULL,
-#else
-# define INIT_RT_MUTEXES(tsk)
-#endif
-
-#ifdef CONFIG_NUMA_BALANCING
-# define INIT_NUMA_BALANCING(tsk)					\
-	.numa_preferred_nid = -1,					\
-	.numa_group = NULL,						\
-	.numa_faults = NULL,
-#else
-# define INIT_NUMA_BALANCING(tsk)
-#endif
-
-#ifdef CONFIG_KASAN
-# define INIT_KASAN(tsk)						\
-	.kasan_depth = 1,
-#else
-# define INIT_KASAN(tsk)
-#endif
-
-#ifdef CONFIG_LIVEPATCH
-# define INIT_LIVEPATCH(tsk)						\
-	.patch_state = KLP_UNDEFINED,
-#else
-# define INIT_LIVEPATCH(tsk)
-#endif
-
-#ifdef CONFIG_THREAD_INFO_IN_TASK
-# define INIT_TASK_TI(tsk)			\
-	.thread_info = INIT_THREAD_INFO(tsk),	\
-	.stack_refcount = ATOMIC_INIT(1),
-#else
-# define INIT_TASK_TI(tsk)
-#endif
-
-#ifdef CONFIG_SECURITY
-#define INIT_TASK_SECURITY .security = NULL,
-#else
-#define INIT_TASK_SECURITY
-#endif
-
-/*
- *  INIT_TASK is used to set up the first task table, touch at
- * your own risk!. Base=0, limit=0x1fffff (=2MB)
- */
-#define INIT_TASK(tsk)	\
-{									\
-	INIT_TASK_TI(tsk)						\
-	.state		= 0,						\
-	.stack		= init_stack,					\
-	.usage		= ATOMIC_INIT(2),				\
-	.flags		= PF_KTHREAD,					\
-	.prio		= MAX_PRIO-20,					\
-	.static_prio	= MAX_PRIO-20,					\
-	.normal_prio	= MAX_PRIO-20,					\
-	.policy		= SCHED_NORMAL,					\
-	.cpus_allowed	= CPU_MASK_ALL,					\
-	.nr_cpus_allowed= NR_CPUS,					\
-	.mm		= NULL,						\
-	.active_mm	= &init_mm,					\
-	.restart_block = {						\
-		.fn = do_no_restart_syscall,				\
-	},								\
-	.se		= {						\
-		.group_node 	= LIST_HEAD_INIT(tsk.se.group_node),	\
-	},								\
-	.rt		= {						\
-		.run_list	= LIST_HEAD_INIT(tsk.rt.run_list),	\
-		.time_slice	= RR_TIMESLICE,				\
-	},								\
-	.tasks		= LIST_HEAD_INIT(tsk.tasks),			\
-	INIT_PUSHABLE_TASKS(tsk)					\
-	INIT_CGROUP_SCHED(tsk)						\
-	.ptraced	= LIST_HEAD_INIT(tsk.ptraced),			\
-	.ptrace_entry	= LIST_HEAD_INIT(tsk.ptrace_entry),		\
-	.real_parent	= &tsk,						\
-	.parent		= &tsk,						\
-	.children	= LIST_HEAD_INIT(tsk.children),			\
-	.sibling	= LIST_HEAD_INIT(tsk.sibling),			\
-	.group_leader	= &tsk,						\
-	RCU_POINTER_INITIALIZER(real_cred, &init_cred),			\
-	RCU_POINTER_INITIALIZER(cred, &init_cred),			\
-	.comm		= INIT_TASK_COMM,				\
-	.thread		= INIT_THREAD,					\
-	.fs		= &init_fs,					\
-	.files		= &init_files,					\
-	.signal		= &init_signals,				\
-	.sighand	= &init_sighand,				\
-	.nsproxy	= &init_nsproxy,				\
-	.pending	= {						\
-		.list = LIST_HEAD_INIT(tsk.pending.list),		\
-		.signal = {{0}}},					\
-	.blocked	= {{0}},					\
-	.alloc_lock	= __SPIN_LOCK_UNLOCKED(tsk.alloc_lock),		\
-	.journal_info	= NULL,						\
-	INIT_CPU_TIMERS(tsk)						\
-	.pi_lock	= __RAW_SPIN_LOCK_UNLOCKED(tsk.pi_lock),	\
-	.timer_slack_ns = 50000, /* 50 usec default slack */		\
-	.pids = {							\
-		[PIDTYPE_PID]  = INIT_PID_LINK(PIDTYPE_PID),		\
-		[PIDTYPE_PGID] = INIT_PID_LINK(PIDTYPE_PGID),		\
-		[PIDTYPE_SID]  = INIT_PID_LINK(PIDTYPE_SID),		\
-	},								\
-	.thread_group	= LIST_HEAD_INIT(tsk.thread_group),		\
-	.thread_node	= LIST_HEAD_INIT(init_signals.thread_head),	\
-	INIT_IDS							\
-	INIT_PERF_EVENTS(tsk)						\
-	INIT_TRACE_IRQFLAGS						\
-	INIT_LOCKDEP							\
-	INIT_FTRACE_GRAPH						\
-	INIT_TRACE_RECURSION						\
-	INIT_TASK_RCU_PREEMPT(tsk)					\
-	INIT_TASK_RCU_TASKS(tsk)					\
-	INIT_CPUSET_SEQ(tsk)						\
-	INIT_RT_MUTEXES(tsk)						\
-	INIT_PREV_CPUTIME(tsk)						\
-	INIT_VTIME(tsk)							\
-	INIT_NUMA_BALANCING(tsk)					\
-	INIT_KASAN(tsk)							\
-	INIT_LIVEPATCH(tsk)						\
-	INIT_TASK_SECURITY						\
-}
-
-
 /* Attach to the init_task data structure for proper alignment */
+#ifdef CONFIG_ARCH_TASK_STRUCT_ON_STACK
 #define __init_task_data __attribute__((__section__(".data..init_task")))
+#else
+#define __init_task_data /**/
+#endif
 
+/* Attach to the thread_info data structure for proper alignment */
+#define __init_thread_info __attribute__((__section__(".data..init_thread_info")))
 
 #endif
diff --git a/include/linux/irqflags.h b/include/linux/irqflags.h
index 1b3996ff3f16..9700f00bbc04 100644
--- a/include/linux/irqflags.h
+++ b/include/linux/irqflags.h
@@ -40,7 +40,6 @@ do {						\
 do {						\
 	current->softirq_context--;		\
 } while (0)
-# define INIT_TRACE_IRQFLAGS	.softirqs_enabled = 1,
 #else
 # define trace_hardirqs_on()		do { } while (0)
 # define trace_hardirqs_off()		do { } while (0)
@@ -54,7 +53,6 @@ do {						\
 # define trace_hardirq_exit()		do { } while (0)
 # define lockdep_softirq_enter()	do { } while (0)
 # define lockdep_softirq_exit()		do { } while (0)
-# define INIT_TRACE_IRQFLAGS
 #endif
 
 #if defined(CONFIG_IRQSOFF_TRACER) || \
diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index 3251d9c0d313..795634ee5aa5 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -367,8 +367,6 @@ extern struct pin_cookie lock_pin_lock(struct lockdep_map *lock);
 extern void lock_repin_lock(struct lockdep_map *lock, struct pin_cookie);
 extern void lock_unpin_lock(struct lockdep_map *lock, struct pin_cookie);
 
-# define INIT_LOCKDEP				.lockdep_recursion = 0,
-
 #define lockdep_depth(tsk)	(debug_locks ? (tsk)->lockdep_depth : 0)
 
 #define lockdep_assert_held(l)	do {				\
@@ -426,7 +424,6 @@ static inline void lockdep_on(void)
  * #ifdef the call himself.
  */
 
-# define INIT_LOCKDEP
 # define lockdep_reset()		do { debug_locks = 1; } while (0)
 # define lockdep_free_key_range(start, size)	do { } while (0)
 # define lockdep_sys_exit() 			do { } while (0)
diff --git a/include/linux/sched.h b/include/linux/sched.h
index d2588263a989..68a504f6e474 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1446,12 +1446,21 @@ extern void ia64_set_curr_task(int cpu, struct task_struct *p);
 void yield(void);
 
 union thread_union {
+#ifndef CONFIG_ARCH_TASK_STRUCT_ON_STACK
+	struct task_struct task;
+#endif
 #ifndef CONFIG_THREAD_INFO_IN_TASK
 	struct thread_info thread_info;
 #endif
 	unsigned long stack[THREAD_SIZE/sizeof(long)];
 };
 
+#ifndef CONFIG_THREAD_INFO_IN_TASK
+extern struct thread_info init_thread_info;
+#endif
+
+extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)];
+
 #ifdef CONFIG_THREAD_INFO_IN_TASK
 static inline struct thread_info *task_thread_info(struct task_struct *task)
 {