1 files changed, 62 insertions, 142 deletions

diff --git a/kernel/fork.c b/kernel/fork.c
index 3b159c5991b..2b44d82b823 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -40,6 +40,7 @@
 #include <linux/tracehook.h>
 #include <linux/futex.h>
 #include <linux/compat.h>
+#include <linux/kthread.h>
 #include <linux/task_io_accounting_ops.h>
 #include <linux/rcupdate.h>
 #include <linux/ptrace.h>
@@ -66,6 +67,7 @@
 #include <linux/posix-timers.h>
 #include <linux/user-return-notifier.h>
 #include <linux/oom.h>
+#include <linux/khugepaged.h>
 
 #include <asm/pgtable.h>
 #include <asm/pgalloc.h>
@@ -108,20 +110,25 @@ int nr_processes(void)
 }
 
 #ifndef __HAVE_ARCH_TASK_STRUCT_ALLOCATOR
-# define alloc_task_struct()	kmem_cache_alloc(task_struct_cachep, GFP_KERNEL)
-# define free_task_struct(tsk)	kmem_cache_free(task_struct_cachep, (tsk))
+# define alloc_task_struct_node(node)		\
+		kmem_cache_alloc_node(task_struct_cachep, GFP_KERNEL, node)
+# define free_task_struct(tsk)			\
+		kmem_cache_free(task_struct_cachep, (tsk))
 static struct kmem_cache *task_struct_cachep;
 #endif
 
 #ifndef __HAVE_ARCH_THREAD_INFO_ALLOCATOR
-static inline struct thread_info *alloc_thread_info(struct task_struct *tsk)
+static struct thread_info *alloc_thread_info_node(struct task_struct *tsk,
+						  int node)
 {
 #ifdef CONFIG_DEBUG_STACK_USAGE
 	gfp_t mask = GFP_KERNEL | __GFP_ZERO;
 #else
 	gfp_t mask = GFP_KERNEL;
 #endif
-	return (struct thread_info *)__get_free_pages(mask, THREAD_SIZE_ORDER);
+	struct page *page = alloc_pages_node(node, mask, THREAD_SIZE_ORDER);
+
+	return page ? page_address(page) : NULL;
 }
 
 static inline void free_thread_info(struct thread_info *ti)
@@ -169,6 +176,7 @@ EXPORT_SYMBOL(free_task);
 static inline void free_signal_struct(struct signal_struct *sig)
 {
 	taskstats_tgid_free(sig);
+	sched_autogroup_exit(sig);
 	kmem_cache_free(signal_cachep, sig);
 }
 
@@ -191,6 +199,7 @@ void __put_task_struct(struct task_struct *tsk)
 	if (!profile_handoff_task(tsk))
 		free_task(tsk);
 }
+EXPORT_SYMBOL_GPL(__put_task_struct);
 
 /*
  * macro override instead of weak attribute alias, to workaround
@@ -246,16 +255,16 @@ static struct task_struct *dup_task_struct(struct task_struct *orig)
 	struct task_struct *tsk;
 	struct thread_info *ti;
 	unsigned long *stackend;
-
+	int node = tsk_fork_get_node(orig);
 	int err;
 
 	prepare_to_copy(orig);
 
-	tsk = alloc_task_struct();
+	tsk = alloc_task_struct_node(node);
 	if (!tsk)
 		return NULL;
 
-	ti = alloc_thread_info(tsk);
+	ti = alloc_thread_info_node(tsk, node);
 	if (!ti) {
 		free_task_struct(tsk);
 		return NULL;
@@ -273,6 +282,7 @@ static struct task_struct *dup_task_struct(struct task_struct *orig)
 
 	setup_thread_stack(tsk, orig);
 	clear_user_return_notifier(tsk);
+	clear_tsk_need_resched(tsk);
 	stackend = end_of_stack(tsk);
 	*stackend = STACK_END_MAGIC;	/* for overflow detection */
 
@@ -328,6 +338,9 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
 	retval = ksm_fork(mm, oldmm);
 	if (retval)
 		goto out;
+	retval = khugepaged_fork(mm, oldmm);
+	if (retval)
+		goto out;
 
 	prev = NULL;
 	for (mpnt = oldmm->mmap; mpnt; mpnt = mpnt->vm_next) {
@@ -527,6 +540,9 @@ void __mmdrop(struct mm_struct *mm)
 	mm_free_pgd(mm);
 	destroy_context(mm);
 	mmu_notifier_mm_destroy(mm);
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+	VM_BUG_ON(mm->pmd_huge_pte);
+#endif
 	free_mm(mm);
 }
 EXPORT_SYMBOL_GPL(__mmdrop);
@@ -541,6 +557,7 @@ void mmput(struct mm_struct *mm)
 	if (atomic_dec_and_test(&mm->mm_users)) {
 		exit_aio(mm);
 		ksm_exit(mm);
+		khugepaged_exit(mm); /* must run before exit_mmap */
 		exit_mmap(mm);
 		set_mm_exe_file(mm, NULL);
 		if (!list_empty(&mm->mmlist)) {
@@ -667,6 +684,10 @@ struct mm_struct *dup_mm(struct task_struct *tsk)
 	mm->token_priority = 0;
 	mm->last_interval = 0;
 
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+	mm->pmd_huge_pte = NULL;
+#endif
+
 	if (!mm_init(mm, tsk))
 		goto fail_nomem;
 
@@ -904,9 +925,11 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
 	posix_cpu_timers_init_group(sig);
 
 	tty_audit_fork(sig);
+	sched_autogroup_fork(sig);
 
 	sig->oom_adj = current->signal->oom_adj;
 	sig->oom_score_adj = current->signal->oom_score_adj;
+	sig->oom_score_adj_min = current->signal->oom_score_adj_min;
 
 	mutex_init(&sig->cred_guard_mutex);
 
@@ -1080,7 +1103,6 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 
 	posix_cpu_timers_init(p);
 
-	p->lock_depth = -1;		/* -1 = no lock */
 	do_posix_clock_monotonic_gettime(&p->start_time);
 	p->real_start_time = p->start_time;
 	monotonic_to_bootbased(&p->real_start_time);
@@ -1130,7 +1152,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 #endif
 
 	/* Perform scheduler related setup. Assign this task to a CPU. */
-	sched_fork(p, clone_flags);
+	sched_fork(p);
 
 	retval = perf_event_init_task(p);
 	if (retval)
@@ -1164,12 +1186,6 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 		pid = alloc_pid(p->nsproxy->pid_ns);
 		if (!pid)
 			goto bad_fork_cleanup_io;
-
-		if (clone_flags & CLONE_NEWPID) {
-			retval = pid_ns_prepare_proc(p->nsproxy->pid_ns);
-			if (retval < 0)
-				goto bad_fork_free_pid;
-		}
 	}
 
 	p->pid = pid_nr(pid);
@@ -1188,6 +1204,9 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 	 * Clear TID on mm_release()?
 	 */
 	p->clear_child_tid = (clone_flags & CLONE_CHILD_CLEARTID) ? child_tidptr: NULL;
+#ifdef CONFIG_BLOCK
+	p->plug = NULL;
+#endif
 #ifdef CONFIG_FUTEX
 	p->robust_list = NULL;
 #ifdef CONFIG_COMPAT
@@ -1273,7 +1292,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 		tracehook_finish_clone(p, clone_flags, trace);
 
 		if (thread_group_leader(p)) {
-			if (clone_flags & CLONE_NEWPID)
+			if (is_child_reaper(pid))
 				p->nsproxy->pid_ns->child_reaper = p;
 
 			p->signal->leader_pid = pid;
@@ -1282,7 +1301,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 			attach_pid(p, PIDTYPE_SID, task_session(current));
 			list_add_tail(&p->sibling, &p->real_parent->children);
 			list_add_tail_rcu(&p->tasks, &init_task.tasks);
-			__get_cpu_var(process_counts)++;
+			__this_cpu_inc(process_counts);
 		}
 		attach_pid(p, PIDTYPE_PID, pid);
 		nr_threads++;
@@ -1407,23 +1426,6 @@ long do_fork(unsigned long clone_flags,
 	}
 
 	/*
-	 * 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.
 	 */
 	if (likely(user_mode(regs)))
@@ -1461,16 +1463,7 @@ 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);
-		}
+		wake_up_new_task(p);
 
 		tracehook_report_clone_complete(trace, regs,
 						clone_flags, nr, p);
@@ -1522,38 +1515,24 @@ void __init proc_caches_init(void)
 }
 
 /*
- * Check constraints on flags passed to the unshare system call and
- * force unsharing of additional process context as appropriate.
+ * Check constraints on flags passed to the unshare system call.
  */
-static void check_unshare_flags(unsigned long *flags_ptr)
+static int check_unshare_flags(unsigned long unshare_flags)
 {
+	if (unshare_flags & ~(CLONE_THREAD|CLONE_FS|CLONE_NEWNS|CLONE_SIGHAND|
+				CLONE_VM|CLONE_FILES|CLONE_SYSVSEM|
+				CLONE_NEWUTS|CLONE_NEWIPC|CLONE_NEWNET))
+		return -EINVAL;
 	/*
-	 * If unsharing a thread from a thread group, must also
-	 * unshare vm.
-	 */
-	if (*flags_ptr & CLONE_THREAD)
-		*flags_ptr |= CLONE_VM;
-
-	/*
-	 * If unsharing vm, must also unshare signal handlers.
-	 */
-	if (*flags_ptr & CLONE_VM)
-		*flags_ptr |= CLONE_SIGHAND;
-
-	/*
-	 * If unsharing namespace, must also unshare filesystem information.
+	 * Not implemented, but pretend it works if there is nothing to
+	 * unshare. Note that unsharing CLONE_THREAD or CLONE_SIGHAND
+	 * needs to unshare vm.
 	 */
-	if (*flags_ptr & CLONE_NEWNS)
-		*flags_ptr |= CLONE_FS;
-}
-
-/*
- * Unsharing of tasks created with CLONE_THREAD is not supported yet
- */
-static int unshare_thread(unsigned long unshare_flags)
-{
-	if (unshare_flags & CLONE_THREAD)
-		return -EINVAL;
+	if (unshare_flags & (CLONE_THREAD | CLONE_SIGHAND | CLONE_VM)) {
+		/* FIXME: get_task_mm() increments ->mm_users */
+		if (atomic_read(&current->mm->mm_users) > 1)
+			return -EINVAL;
+	}
 
 	return 0;
 }
@@ -1580,34 +1559,6 @@ static int unshare_fs(unsigned long unshare_flags, struct fs_struct **new_fsp)
 }
 
 /*
- * Unsharing of sighand is not supported yet
- */
-static int unshare_sighand(unsigned long unshare_flags, struct sighand_struct **new_sighp)
-{
-	struct sighand_struct *sigh = current->sighand;
-
-	if ((unshare_flags & CLONE_SIGHAND) && atomic_read(&sigh->count) > 1)
-		return -EINVAL;
-	else
-		return 0;
-}
-
-/*
- * Unshare vm if it is being shared
- */
-static int unshare_vm(unsigned long unshare_flags, struct mm_struct **new_mmp)
-{
-	struct mm_struct *mm = current->mm;
-
-	if ((unshare_flags & CLONE_VM) &&
-	    (mm && atomic_read(&mm->mm_users) > 1)) {
-		return -EINVAL;
-	}
-
-	return 0;
-}
-
-/*
  * Unshare file descriptor table if it is being shared
  */
 static int unshare_fd(unsigned long unshare_flags, struct files_struct **new_fdp)
@@ -1635,45 +1586,37 @@ static int unshare_fd(unsigned long unshare_flags, struct files_struct **new_fdp
  */
 SYSCALL_DEFINE1(unshare, unsigned long, unshare_flags)
 {
-	int err = 0;
 	struct fs_struct *fs, *new_fs = NULL;
-	struct sighand_struct *new_sigh = NULL;
-	struct mm_struct *mm, *new_mm = NULL, *active_mm = NULL;
 	struct files_struct *fd, *new_fd = NULL;
 	struct nsproxy *new_nsproxy = NULL;
 	int do_sysvsem = 0;
+	int err;
 
-	check_unshare_flags(&unshare_flags);
-
-	/* Return -EINVAL for all unsupported flags */
-	err = -EINVAL;
-	if (unshare_flags & ~(CLONE_THREAD|CLONE_FS|CLONE_NEWNS|CLONE_SIGHAND|
-				CLONE_VM|CLONE_FILES|CLONE_SYSVSEM|
-				CLONE_NEWUTS|CLONE_NEWIPC|CLONE_NEWNET))
+	err = check_unshare_flags(unshare_flags);
+	if (err)
 		goto bad_unshare_out;
 
 	/*
+	 * If unsharing namespace, must also unshare filesystem information.
+	 */
+	if (unshare_flags & CLONE_NEWNS)
+		unshare_flags |= CLONE_FS;
+	/*
 	 * CLONE_NEWIPC must also detach from the undolist: after switching
 	 * to a new ipc namespace, the semaphore arrays from the old
 	 * namespace are unreachable.
 	 */
 	if (unshare_flags & (CLONE_NEWIPC|CLONE_SYSVSEM))
 		do_sysvsem = 1;
-	if ((err = unshare_thread(unshare_flags)))
-		goto bad_unshare_out;
 	if ((err = unshare_fs(unshare_flags, &new_fs)))
-		goto bad_unshare_cleanup_thread;
-	if ((err = unshare_sighand(unshare_flags, &new_sigh)))
-		goto bad_unshare_cleanup_fs;
-	if ((err = unshare_vm(unshare_flags, &new_mm)))
-		goto bad_unshare_cleanup_sigh;
+		goto bad_unshare_out;
 	if ((err = unshare_fd(unshare_flags, &new_fd)))
-		goto bad_unshare_cleanup_vm;
+		goto bad_unshare_cleanup_fs;
 	if ((err = unshare_nsproxy_namespaces(unshare_flags, &new_nsproxy,
 			new_fs)))
 		goto bad_unshare_cleanup_fd;
 
-	if (new_fs ||  new_mm || new_fd || do_sysvsem || new_nsproxy) {
+	if (new_fs || new_fd || do_sysvsem || new_nsproxy) {
 		if (do_sysvsem) {
 			/*
 			 * CLONE_SYSVSEM is equivalent to sys_exit().
@@ -1699,19 +1642,6 @@ SYSCALL_DEFINE1(unshare, unsigned long, unshare_flags)
 			spin_unlock(&fs->lock);
 		}
 
-		if (new_mm) {
-			mm = current->mm;
-			active_mm = current->active_mm;
-			current->mm = new_mm;
-			current->active_mm = new_mm;
-			if (current->signal->oom_score_adj == OOM_SCORE_ADJ_MIN) {
-				atomic_dec(&mm->oom_disable_count);
-				atomic_inc(&new_mm->oom_disable_count);
-			}
-			activate_mm(active_mm, new_mm);
-			new_mm = mm;
-		}
-
 		if (new_fd) {
 			fd = current->files;
 			current->files = new_fd;
@@ -1728,20 +1658,10 @@ bad_unshare_cleanup_fd:
 	if (new_fd)
 		put_files_struct(new_fd);
 
-bad_unshare_cleanup_vm:
-	if (new_mm)
-		mmput(new_mm);
-
-bad_unshare_cleanup_sigh:
-	if (new_sigh)
-		if (atomic_dec_and_test(&new_sigh->count))
-			kmem_cache_free(sighand_cachep, new_sigh);
-
 bad_unshare_cleanup_fs:
 	if (new_fs)
 		free_fs_struct(new_fs);
 
-bad_unshare_cleanup_thread:
 bad_unshare_out:
 	return err;
 }