sched: remove long deprecated CLONE_STOPPED flag

This warning was added in commit bdff746a ("clone: prepare to recycle
CLONE_STOPPED") three years ago.  2.6.26 came and went.  As far as I know,
no-one is actually using CLONE_STOPPED.
Signed-off-by: NDave Jones <davej@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

include/linux/sched.h

@@ -21,7 +21,8 @@
 #define CLONE_DETACHED		0x00400000	/* Unused, ignored */
 #define CLONE_UNTRACED		0x00800000	/* set if the tracing process can't force CLONE_PTRACE on this clone */
 #define CLONE_CHILD_SETTID	0x01000000	/* set the TID in the child */
-#define CLONE_STOPPED		0x02000000	/* Start in stopped state */
+/* 0x02000000 was previously the unused CLONE_STOPPED (Start in stopped state)
+   and is now available for re-use. */
 #define CLONE_NEWUTS		0x04000000	/* New utsname group? */
 #define CLONE_NEWIPC		0x08000000	/* New ipcs */
 #define CLONE_NEWUSER		0x10000000	/* New user namespace */

kernel/fork.c

@@ -1409,23 +1409,6 @@ long do_fork(unsigned long clone_flags,
 			return -EPERM;
 	}
 
-	/*
-	 * We hope to recycle these flags after 2.6.26
-	 */
-	if (unlikely(clone_flags & CLONE_STOPPED)) {
-		static int __read_mostly count = 100;
-
-		if (count > 0 && printk_ratelimit()) {
-			char comm[TASK_COMM_LEN];
-
-			count--;
-			printk(KERN_INFO "fork(): process `%s' used deprecated "
-					"clone flags 0x%lx\n",
-				get_task_comm(comm, current),
-				clone_flags & CLONE_STOPPED);
-		}
-	}
-
 	/*
 	 * When called from kernel_thread, don't do user tracing stuff.
 	 */
@@ -1464,16 +1447,7 @@ long do_fork(unsigned long clone_flags,
 		 */
 		p->flags &= ~PF_STARTING;
 
-		if (unlikely(clone_flags & CLONE_STOPPED)) {
-			/*
-			 * We'll start up with an immediate SIGSTOP.
-			 */
-			sigaddset(&p->pending.signal, SIGSTOP);
-			set_tsk_thread_flag(p, TIF_SIGPENDING);
-			__set_task_state(p, TASK_STOPPED);
-		} else {
 		wake_up_new_task(p, clone_flags);
-		}
 
 		tracehook_report_clone_complete(trace, regs,
 						clone_flags, nr, p);