Merge changes between r9801 and r10031 from /fsf/trunk.

git-svn-id: svn://svn.eglibc.org/trunk@10032 7b3dc134-2b1b-0410-93df-9e9f96275f8d

4 files changed, 75 insertions, 33 deletions

diff --git a/libc/nptl/ChangeLog b/libc/nptl/ChangeLog
index c81eb03b7..f51ad4326 100644
--- a/libc/nptl/ChangeLog
+++ b/libc/nptl/ChangeLog
@@ -1,3 +1,28 @@
+2010-03-09  Ulrich Drepper  <drepper@redhat.com>
+
+	* pthread_create.c (__pthread_create_2_1): If priorities are incorrect
+	and the call fails wake eventually waiting setxid threads.  Don't free
+	stack here if we try starting a thread.
+	* sysdeps/pthread/createthread.c (do_clone): Only wake setxid waiter
+	if the clone call failed.
+
+2010-03-08  Andreas Schwab  <schwab@redhat.com>
+
+	* pthread_create.c (__pthread_create_2_1): Don't set setxid_futex.
+	* allocatestack.c (get_cached_stack): Set setxid_futex.
+	(allocate_stack): Likewise.
+
+2010-03-05  Andreas Schwab  <schwab@redhat.com>
+	    Ulrich Drepper  <drepper@redhat.com>
+
+	* allocatestack.c (setxid_mark_thread): Delay handling of thread if
+	it is creating a thread or it is just being created.
+	* pthread_create.c (start_thread): Wake setxid thread if it is
+	waiting.
+	(__pthread_create_2_1): Initialize setxid_futex.
+	* sysdeps/pthread/createthread.c (do_clone): Wake setxid thread if it
+	is waiting.
+
 2010-01-15  Ulrich Drepper  <drepper@redhat.com>
 
 	* sysdeps/unix/sysv/linux/i386/i486/pthread_cond_timedwait.S:
diff --git a/libc/nptl/allocatestack.c b/libc/nptl/allocatestack.c
index 3c3585fe3..831e98e4c 100644
--- a/libc/nptl/allocatestack.c
+++ b/libc/nptl/allocatestack.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2002-2007, 2009 Free Software Foundation, Inc.
+/* Copyright (C) 2002-2007, 2009, 2010 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
 
@@ -213,6 +213,9 @@ get_cached_stack (size_t *sizep, void **memp)
       return NULL;
     }
 
+  /* Don't allow setxid until cloned.  */
+  result->setxid_futex = -1;
+
   /* Dequeue the entry.  */
   stack_list_del (&result->list);
 
@@ -380,7 +383,7 @@ allocate_stack (const struct pthread_attr *attr, struct pthread **pdp,
 			       - TLS_TCB_SIZE - adj);
 #elif TLS_DTV_AT_TP
       pd = (struct pthread *) (((uintptr_t) attr->stackaddr
-			        - __static_tls_size - adj)
+				- __static_tls_size - adj)
 			       - TLS_PRE_TCB_SIZE);
 #endif
 
@@ -418,6 +421,9 @@ allocate_stack (const struct pthread_attr *attr, struct pthread **pdp,
       /* The process ID is also the same as that of the caller.  */
       pd->pid = THREAD_GETMEM (THREAD_SELF, pid);
 
+      /* Don't allow setxid until cloned.  */
+      pd->setxid_futex = -1;
+
       /* Allocate the DTV for this thread.  */
       if (_dl_allocate_tls (TLS_TPADJ (pd)) == NULL)
 	{
@@ -546,7 +552,7 @@ allocate_stack (const struct pthread_attr *attr, struct pthread **pdp,
 #ifndef __ASSUME_PRIVATE_FUTEX
 	  /* The thread must know when private futexes are supported.  */
 	  pd->header.private_futex = THREAD_GETMEM (THREAD_SELF,
-                                                    header.private_futex);
+						    header.private_futex);
 #endif
 
 #ifdef NEED_DL_SYSINFO
@@ -554,6 +560,9 @@ allocate_stack (const struct pthread_attr *attr, struct pthread **pdp,
 	  THREAD_SYSINFO(pd) = THREAD_SELF_SYSINFO;
 #endif
 
+	  /* Don't allow setxid until cloned.  */
+	  pd->setxid_futex = -1;
+
 	  /* The process ID is also the same as that of the caller.  */
 	  pd->pid = THREAD_GETMEM (THREAD_SELF, pid);
 
@@ -969,6 +978,13 @@ setxid_mark_thread (struct xid_command *cmdp, struct pthread *t)
 {
   int ch;
 
+  /* Wait until this thread is cloned.  */
+  if (t->setxid_futex == -1
+      && ! atomic_compare_and_exchange_bool_acq (&t->setxid_futex, -2, -1))
+    do
+      lll_futex_wait (&t->setxid_futex, -2, LLL_PRIVATE);
+    while (t->setxid_futex == -2);
+
   /* Don't let the thread exit before the setxid handler runs.  */
   t->setxid_futex = 0;
 
diff --git a/libc/nptl/pthread_create.c b/libc/nptl/pthread_create.c
index ddf377cdb..649cdae8f 100644
--- a/libc/nptl/pthread_create.c
+++ b/libc/nptl/pthread_create.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2002-2007,2008,2009 Free Software Foundation, Inc.
+/* Copyright (C) 2002-2007,2008,2009,2010 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
 
@@ -242,6 +242,10 @@ start_thread (void *arg)
   __resp = &pd->res;
 #endif
 
+  /* Allow setxid from now onwards.  */
+  if (__builtin_expect (atomic_exchange_acq (&pd->setxid_futex, 0) == -2, 0))
+    lll_futex_wake (&pd->setxid_futex, 1, LLL_PRIVATE);
+
 #ifdef __NR_set_robust_list
 # ifndef __ASSUME_SET_ROBUST_LIST
   if (__set_robust_list_avail >= 0)
@@ -538,33 +542,23 @@ __pthread_create_2_1 (newthread, attr, start_routine, arg)
       if (pd->schedparam.sched_priority < minprio
 	  || pd->schedparam.sched_priority > maxprio)
 	{
-	  err = EINVAL;
-	  goto errout;
+	  /* Perhaps a thread wants to change the IDs and if waiting
+	     for this stillborn thread.  */
+	  if (__builtin_expect (atomic_exchange_acq (&pd->setxid_futex, 0)
+				== -2, 0))
+	    lll_futex_wake (&pd->setxid_futex, 1, LLL_PRIVATE);
+
+	  __deallocate_stack (pd);
+
+	  return EINVAL;
 	}
     }
 
   /* Pass the descriptor to the caller.  */
   *newthread = (pthread_t) pd;
 
-  /* Remember whether the thread is detached or not.  In case of an
-     error we have to free the stacks of non-detached stillborn
-     threads.  */
-  bool is_detached = IS_DETACHED (pd);
-
   /* Start the thread.  */
-  err = create_thread (pd, iattr, STACK_VARIABLES_ARGS);
-  if (err != 0)
-    {
-      /* Something went wrong.  Free the resources.  */
-      if (!is_detached)
-	{
-	errout:
-	  __deallocate_stack (pd);
-	}
-      return err;
-    }
-
-  return 0;
+  return create_thread (pd, iattr, STACK_VARIABLES_ARGS);
 }
 versioned_symbol (libpthread, __pthread_create_2_1, pthread_create, GLIBC_2_1);
 
diff --git a/libc/nptl/sysdeps/pthread/createthread.c b/libc/nptl/sysdeps/pthread/createthread.c
index 66fafe805..8d96387a9 100644
--- a/libc/nptl/sysdeps/pthread/createthread.c
+++ b/libc/nptl/sysdeps/pthread/createthread.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2002-2007, 2008 Free Software Foundation, Inc.
+/* Copyright (C) 2002-2007, 2008, 2010 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
 
@@ -28,7 +28,7 @@
 #include "kernel-features.h"
 
 
-#define CLONE_SIGNAL    	(CLONE_SIGHAND | CLONE_THREAD)
+#define CLONE_SIGNAL		(CLONE_SIGHAND | CLONE_THREAD)
 
 /* Unless otherwise specified, the thread "register" is going to be
    initialized with a pointer to the TCB.  */
@@ -72,16 +72,20 @@ do_clone (struct pthread *pd, const struct pthread_attr *attr,
      that cares whether the thread count is correct.  */
   atomic_increment (&__nptl_nthreads);
 
-  if (ARCH_CLONE (fct, STACK_VARIABLES_ARGS, clone_flags,
-		  pd, &pd->tid, TLS_VALUE, &pd->tid) == -1)
+  int rc = ARCH_CLONE (fct, STACK_VARIABLES_ARGS, clone_flags,
+		       pd, &pd->tid, TLS_VALUE, &pd->tid);
+
+  if (__builtin_expect (rc == -1, 0))
     {
       atomic_decrement (&__nptl_nthreads); /* Oops, we lied for a second.  */
 
-      /* Failed.  If the thread is detached, remove the TCB here since
-	 the caller cannot do this.  The caller remembered the thread
-	 as detached and cannot reverify that it is not since it must
-	 not access the thread descriptor again.  */
-      if (IS_DETACHED (pd))
+      /* Perhaps a thread wants to change the IDs and if waiting
+	 for this stillborn thread.  */
+      if (__builtin_expect (atomic_exchange_acq (&pd->setxid_futex, 0)
+			    == -2, 0))
+	lll_futex_wake (&pd->setxid_futex, 1, LLL_PRIVATE);
+
+      /* Free the resources.  */
 	__deallocate_stack (pd);
 
       /* We have to translate error codes.  */
@@ -114,6 +118,9 @@ do_clone (struct pthread *pd, const struct pthread_attr *attr,
 	      (void) INTERNAL_SYSCALL (tkill, err2, 2, pd->tid, SIGCANCEL);
 #endif
 
+	      /* We do not free the stack here because the canceled thread
+		 itself will do this.  */
+
 	      return (INTERNAL_SYSCALL_ERROR_P (res, err)
 		      ? INTERNAL_SYSCALL_ERRNO (res, err)
 		      : 0);