sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>

We are going to split <linux/sched/task.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/task.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

kernel/cgroup/cgroup.c

@@ -41,6 +41,7 @@
 #include <linux/proc_fs.h>
 #include <linux/rcupdate.h>
 #include <linux/sched.h>
+#include <linux/sched/task.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/percpu-rwsem.h>

kernel/cpu.c

@@ -9,6 +9,7 @@
 #include <linux/notifier.h>
 #include <linux/sched/signal.h>
 #include <linux/sched/hotplug.h>
+#include <linux/sched/task.h>
 #include <linux/unistd.h>
 #include <linux/cpu.h>
 #include <linux/oom.h>

kernel/exit.c

@@ -9,6 +9,7 @@
 #include <linux/sched/autogroup.h>
 #include <linux/sched/mm.h>
 #include <linux/sched/stat.h>
+#include <linux/sched/task.h>
 #include <linux/interrupt.h>
 #include <linux/module.h>
 #include <linux/capability.h>

kernel/fork.c

@@ -18,6 +18,7 @@
 #include <linux/sched/user.h>
 #include <linux/sched/numa_balancing.h>
 #include <linux/sched/stat.h>
+#include <linux/sched/task.h>
 #include <linux/rtmutex.h>
 #include <linux/init.h>
 #include <linux/unistd.h>

kernel/kmod.c

@@ -20,6 +20,7 @@
 */
 #include <linux/module.h>
 #include <linux/sched.h>
+#include <linux/sched/task.h>
 #include <linux/syscalls.h>
 #include <linux/unistd.h>
 #include <linux/kmod.h>

kernel/kthread.c

@@ -7,6 +7,7 @@
  */
 #include <uapi/linux/sched/types.h>
 #include <linux/sched.h>
+#include <linux/sched/task.h>
 #include <linux/kthread.h>
 #include <linux/completion.h>
 #include <linux/err.h>

kernel/locking/lockdep.c

@@ -29,6 +29,7 @@
 #include <linux/mutex.h>
 #include <linux/sched.h>
 #include <linux/sched/clock.h>
+#include <linux/sched/task.h>
 #include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/proc_fs.h>

kernel/pid.c

@@ -38,6 +38,7 @@
 #include <linux/syscalls.h>
 #include <linux/proc_ns.h>
 #include <linux/proc_fs.h>
+#include <linux/sched/task.h>
 
 #define pid_hashfn(nr, ns)	\
 	hash_long((unsigned long)nr + (unsigned long)ns, pidhash_shift)

kernel/pid_namespace.c

@@ -19,6 +19,7 @@
 #include <linux/proc_ns.h>
 #include <linux/reboot.h>
 #include <linux/export.h>
+#include <linux/sched/task.h>
 
 struct pid_cache {
 	int nr_ids;

kernel/power/process.c

@@ -13,6 +13,7 @@
 #include <linux/suspend.h>
 #include <linux/module.h>
 #include <linux/sched/debug.h>
+#include <linux/sched/task.h>
 #include <linux/syscalls.h>
 #include <linux/freezer.h>
 #include <linux/delay.h>

kernel/ptrace.c

@@ -12,6 +12,7 @@
 #include <linux/sched.h>
 #include <linux/sched/mm.h>
 #include <linux/sched/coredump.h>
+#include <linux/sched/task.h>
 #include <linux/errno.h>
 #include <linux/mm.h>
 #include <linux/highmem.h>

kernel/sched/sched.h

@@ -14,6 +14,7 @@
 #include <linux/sched/nohz.h>
 #include <linux/sched/debug.h>
 #include <linux/sched/hotplug.h>
+#include <linux/sched/task.h>
 
 #include <linux/u64_stats_sync.h>
 #include <linux/kernel_stat.h>

kernel/signal.c

@@ -16,6 +16,7 @@
 #include <linux/sched.h>
 #include <linux/sched/user.h>
 #include <linux/sched/debug.h>
+#include <linux/sched/task.h>
 #include <linux/fs.h>
 #include <linux/tty.h>
 #include <linux/binfmts.h>

kernel/smpboot.c

@@ -9,6 +9,7 @@
 #include <linux/list.h>
 #include <linux/slab.h>
 #include <linux/sched.h>
+#include <linux/sched/task.h>
 #include <linux/export.h>
 #include <linux/percpu.h>
 #include <linux/kthread.h>

kernel/sys.c

@@ -54,6 +54,7 @@
 #include <linux/sched/stat.h>
 #include <linux/sched/mm.h>
 #include <linux/sched/coredump.h>
+#include <linux/sched/task.h>
 #include <linux/rcupdate.h>
 #include <linux/uidgid.h>
 #include <linux/cred.h>

kernel/trace/ftrace.c

@@ -15,6 +15,7 @@
 
 #include <linux/stop_machine.h>
 #include <linux/clocksource.h>
+#include <linux/sched/task.h>
 #include <linux/kallsyms.h>
 #include <linux/seq_file.h>
 #include <linux/suspend.h>

kernel/tracepoint.c

@@ -25,6 +25,7 @@
 #include <linux/err.h>
 #include <linux/slab.h>
 #include <linux/sched/signal.h>
+#include <linux/sched/task.h>
 #include <linux/static_key.h>
 
 extern struct tracepoint * const __start___tracepoints_ptrs[];