Merge branch 'perf/core' into perf/uprobes

Merge in latest upstream (and the latest perf development tree),
to prepare for tooling changes, and also to pick up v3.4 MM
changes that the uprobes code needs to take care of.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 70 insertions, 26 deletions

diff --git a/kernel/fork.c b/kernel/fork.c
index 26a8f5c25805..ca9a3845ef3e 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -194,6 +194,7 @@ void __put_task_struct(struct task_struct *tsk)
         WARN_ON(atomic_read(&tsk->usage));
         WARN_ON(tsk == current);
 
+        security_task_free(tsk);
         exit_creds(tsk);
         delayacct_tsk_free(tsk);
         put_signal_struct(tsk->signal);
@@ -356,7 +357,7 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
                 charge = 0;
                 if (mpnt->vm_flags & VM_ACCOUNT) {
                         unsigned int len = (mpnt->vm_end - mpnt->vm_start) >> PAGE_SHIFT;
-                        if (security_vm_enough_memory(len))
+                        if (security_vm_enough_memory_mm(oldmm, len)) /* sic */
                                 goto fail_nomem;
                         charge = len;
                 }
@@ -515,6 +516,23 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p)
         return NULL;
 }
 
+static void check_mm(struct mm_struct *mm)
+{
+        int i;
+
+        for (i = 0; i < NR_MM_COUNTERS; i++) {
+                long x = atomic_long_read(&mm->rss_stat.count[i]);
+
+                if (unlikely(x))
+                        printk(KERN_ALERT "BUG: Bad rss-counter state "
+                                          "mm:%p idx:%d val:%ld\n", mm, i, x);
+        }
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+        VM_BUG_ON(mm->pmd_huge_pte);
+#endif
+}
+
 /*
  * Allocate and initialize an mm_struct.
  */
@@ -542,9 +560,7 @@ 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
+        check_mm(mm);
         free_mm(mm);
 }
 EXPORT_SYMBOL_GPL(__mmdrop);
@@ -673,6 +689,38 @@ struct mm_struct *mm_access(struct task_struct *task, unsigned int mode)
         return mm;
 }
 
+static void complete_vfork_done(struct task_struct *tsk)
+{
+        struct completion *vfork;
+
+        task_lock(tsk);
+        vfork = tsk->vfork_done;
+        if (likely(vfork)) {
+                tsk->vfork_done = NULL;
+                complete(vfork);
+        }
+        task_unlock(tsk);
+}
+
+static int wait_for_vfork_done(struct task_struct *child,
+                                struct completion *vfork)
+{
+        int killed;
+
+        freezer_do_not_count();
+        killed = wait_for_completion_killable(vfork);
+        freezer_count();
+
+        if (killed) {
+                task_lock(child);
+                child->vfork_done = NULL;
+                task_unlock(child);
+        }
+
+        put_task_struct(child);
+        return killed;
+}
+
 /* Please note the differences between mmput and mm_release.
  * mmput is called whenever we stop holding onto a mm_struct,
  * error success whatever.
@@ -688,8 +736,6 @@ struct mm_struct *mm_access(struct task_struct *task, unsigned int mode)
  */
 void mm_release(struct task_struct *tsk, struct mm_struct *mm)
 {
-        struct completion *vfork_done = tsk->vfork_done;
-
         /* Get rid of any futexes when releasing the mm */
 #ifdef CONFIG_FUTEX
         if (unlikely(tsk->robust_list)) {
@@ -711,17 +757,15 @@ void mm_release(struct task_struct *tsk, struct mm_struct *mm)
         /* Get rid of any cached register state */
         deactivate_mm(tsk, mm);
 
-        /* notify parent sleeping on vfork() */
-        if (vfork_done) {
-                tsk->vfork_done = NULL;
-                complete(vfork_done);
-        }
+        if (tsk->vfork_done)
+                complete_vfork_done(tsk);
 
         /*
          * If we're exiting normally, clear a user-space tid field if
          * requested.  We leave this alone when dying by signal, to leave
          * the value intact in a core dump, and to save the unnecessary
-         * trouble otherwise.  Userland only wants this done for a sys_exit.
+         * trouble, say, a killed vfork parent shouldn't touch this mm.
+         * Userland only wants this done for a sys_exit.
          */
         if (tsk->clear_child_tid) {
                 if (!(tsk->flags & PF_SIGNALED) &&
@@ -1015,6 +1059,9 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
         sig->oom_score_adj = current->signal->oom_score_adj;
         sig->oom_score_adj_min = current->signal->oom_score_adj_min;
 
+        sig->has_child_subreaper = current->signal->has_child_subreaper ||
+                                   current->signal->is_child_subreaper;
+
         mutex_init(&sig->cred_guard_mutex);
 
         return 0;
@@ -1026,7 +1073,6 @@ static void copy_flags(unsigned long clone_flags, struct task_struct *p)
 
         new_flags &= ~(PF_SUPERPRIV | PF_WQ_WORKER);
         new_flags |= PF_FORKNOEXEC;
-        new_flags |= PF_STARTING;
         p->flags = new_flags;
 }
 
@@ -1203,6 +1249,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 #ifdef CONFIG_CPUSETS
         p->cpuset_mem_spread_rotor = NUMA_NO_NODE;
         p->cpuset_slab_spread_rotor = NUMA_NO_NODE;
+        seqcount_init(&p->mems_allowed_seq);
 #endif
 #ifdef CONFIG_TRACE_IRQFLAGS
         p->irq_events = 0;
@@ -1322,7 +1369,13 @@ static struct task_struct *copy_process(unsigned long clone_flags,
         clear_all_latency_tracing(p);
 
         /* ok, now we should be set up.. */
-        p->exit_signal = (clone_flags & CLONE_THREAD) ? -1 : (clone_flags & CSIGNAL);
+        if (clone_flags & CLONE_THREAD)
+                p->exit_signal = -1;
+        else if (clone_flags & CLONE_PARENT)
+                p->exit_signal = current->group_leader->exit_signal;
+        else
+                p->exit_signal = (clone_flags & CSIGNAL);
+
         p->pdeath_signal = 0;
         p->exit_state = 0;
 
@@ -1557,16 +1610,9 @@ long do_fork(unsigned long clone_flags,
                 if (clone_flags & CLONE_VFORK) {
                         p->vfork_done = &vfork;
                         init_completion(&vfork);
+                        get_task_struct(p);
                 }
 
-                /*
-                 * We set PF_STARTING at creation in case tracing wants to
-                 * use this to distinguish a fully live task from one that
-                 * hasn't finished SIGSTOP raising yet.  Now we clear it
-                 * and set the child going.
-                 */
-                p->flags &= ~PF_STARTING;
-
                 wake_up_new_task(p);
 
                 /* forking complete and child started to run, tell ptracer */
@@ -1574,10 +1620,8 @@ long do_fork(unsigned long clone_flags,
                         ptrace_event(trace, nr);
 
                 if (clone_flags & CLONE_VFORK) {
-                        freezer_do_not_count();
-                        wait_for_completion(&vfork);
-                        freezer_count();
-                        ptrace_event(PTRACE_EVENT_VFORK_DONE, nr);
+                        if (!wait_for_vfork_done(p, &vfork))
+                                ptrace_event(PTRACE_EVENT_VFORK_DONE, nr);
                 }
         } else {
                 nr = PTR_ERR(p);