nptl: Reinstate pthread_timedjoin_np as a cancellation point (BZ#24215)

Patch ce7eb0e90315 ("nptl: Cleanup cancellation macros") changed the
join sequence for internal common __pthread_timedjoin_ex to use the
new macro lll_wait_tid.  The idea was this macro would issue the
cancellable futex operation depending whether the timeout is used or
not.  However if a timeout is used, __lll_timedwait_tid is called and
it is not a cancellable entrypoint.

This patch fixes it by simplifying the code in various ways:

  - Instead of adding the cancellation handling on __lll_timedwait_tid,
    it moves the generic implementation to pthread_join_common.c (called
    now timedwait_tid with some fixes to use the correct type for pid).

  - The llvm_wait_tid macro is removed, along with its replication on
    x86_64, i686, and sparc arch-specific lowlevellock.h.

  - sparc32 __lll_timedwait_tid is also removed, since the code is similar
    to generic one.

  - x86_64 and i386 provides arch-specific __lll_timedwait_tid which is
    also removed since they are similar in functionality to generic C code
    and there is no indication it is better than compiler generated code.

New tests, tst-join8 and tst-join9, are provided to check if
pthread_timedjoin_np acts as a cancellation point.

Checked on x86_64-linux-gnu, i686-linux-gnu, sparcv9-linux-gnu, and
aarch64-linux-gnu.

	[BZ #24215]
	* nptl/Makefile (lpthread-routines): Remove lll_timedwait_tid.
	(tests): Add tst-join8 tst-join9.
	* nptl/lll_timedwait_tid.c: Remove file.
	* sysdeps/sparc/sparc32/lll_timedwait_tid.c: Likewise.
	* sysdeps/unix/sysv/linux/i386/lll_timedwait_tid.c: Likewise.
	* sysdeps/sysv/linux/x86_64/lll_timedwait_tid.c: Likewise.
	* nptl/pthread_join_common.c (timedwait_tid): New function.
	(__pthread_timedjoin_ex): Act as cancellation entrypoint is block
	is set.
	* nptl/tst-join5.c (thread_join): New function.
	(tf1, tf2, do_test): Use libsupport and add pthread_timedjoin_np
	check.
	* nptl/tst-join8.c: New file.
	* nptl/tst-join9.c: Likewise.
	* sysdeps/nptl/lowlevellock-futex.h (lll_futex_wait_cancel,
	lll_futex_timed_wait_cancel): Add generic macros.
	* sysdeps/nptl/lowlevellock.h (__lll_timedwait_tid, lll_wait_tid):
	Remove definitions.
	* sysdeps/unix/sysv/linux/i386/lowlevellock.h: Likewise.
	* sysdeps/unix/sysv/linux/sparc/lowlevellock.h: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/lowlevellock.h: Likewise.
	* sysdeps/sparc/sparc32/lowlevellock.c (__lll_timedwait_tid):
	Remove function.
	* sysdeps/unix/sysv/linux/i386/lowlevellock.S (__lll_timedwait_tid):
	Likewise.
	* sysdeps/unix/sysv/linux/x86_64/lowlevellock.S: Likewise.
	* sysdeps/unix/sysv/linux/lowlevellock-futex.h
	(lll_futex_timed_wait_cancel): New macro.

1 files changed, 34 insertions, 58 deletions

diff --git a/nptl/tst-join5.c b/nptl/tst-join5.c
index f60a024baa..39f74dce09 100644
--- a/nptl/tst-join5.c
+++ b/nptl/tst-join5.c
@@ -23,6 +23,8 @@
 #include <time.h>
 #include <unistd.h>
 
+#include <support/check.h>
+#include <support/xthread.h>
 
 static void
 wait_code (void)
@@ -37,22 +39,31 @@ wait_code (void)
 static pthread_barrier_t b;
 #endif
 
+static int
+thread_join (pthread_t thread, void **retval)
+{
+#ifdef USE_PTHREAD_TIMEDJOIN_NP
+  struct timespec tv;
+  TEST_COMPARE (clock_gettime (CLOCK_REALTIME, &tv), 0);
+  /* Arbitrary large timeout to make it act as pthread_join.  */
+  tv.tv_sec += 1000;
+  return pthread_timedjoin_np ((pthread_t) thread, retval, &tv);
+#else
+  return pthread_join ((pthread_t) thread, retval);
+#endif
+}
+
 
 static void *
 tf1 (void *arg)
 {
 #ifdef WAIT_IN_CHILD
-  int e = pthread_barrier_wait (&b);
-  if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD)
-    {
-      printf ("%s: barrier_wait failed\n", __func__);
-      exit (1);
-    }
+  xpthread_barrier_wait (&b);
 
   wait_code ();
 #endif
 
-  pthread_join ((pthread_t) arg, NULL);
+  thread_join ((pthread_t) arg, NULL);
 
   exit (42);
 }
@@ -62,16 +73,12 @@ static void *
 tf2 (void *arg)
 {
 #ifdef WAIT_IN_CHILD
-  int e = pthread_barrier_wait (&b);
-  if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD)
-    {
-      printf ("%s: barrier_wait failed\n", __func__);
-      exit (1);
-    }
+  xpthread_barrier_wait (&b);
 
   wait_code ();
 #endif
-  pthread_join ((pthread_t) arg, NULL);
+
+  thread_join ((pthread_t) arg, NULL);
 
   exit (43);
 }
@@ -81,16 +88,12 @@ static int
 do_test (void)
 {
 #ifdef WAIT_IN_CHILD
-  if (pthread_barrier_init (&b, NULL, 2) != 0)
-    {
-      puts ("barrier_init failed");
-      return 1;
-    }
+  xpthread_barrier_init (&b, NULL, 2);
 #endif
 
   pthread_t th;
 
-  int err = pthread_join (pthread_self (), NULL);
+  int err = thread_join (pthread_self (), NULL);
   if (err == 0)
     {
       puts ("1st circular join succeeded");
@@ -102,33 +105,20 @@ do_test (void)
       return 1;
     }
 
-  if (pthread_create (&th, NULL, tf1, (void *) pthread_self ()) != 0)
-    {
-      puts ("1st create failed");
-      return 1;
-    }
+  th = xpthread_create (NULL, tf1, (void *) pthread_self ());
 
 #ifndef WAIT_IN_CHILD
   wait_code ();
 #endif
 
-  if (pthread_cancel (th) != 0)
-    {
-      puts ("cannot cancel 1st thread");
-      return 1;
-    }
+  xpthread_cancel (th);
 
 #ifdef WAIT_IN_CHILD
-  int e = pthread_barrier_wait (&b);
-  if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD)
-    {
-      printf ("%s: barrier_wait failed\n", __func__);
-      return 1;
-    }
+  xpthread_barrier_wait (&b);
 #endif
 
   void *r;
-  err = pthread_join (th, &r);
+  err = thread_join (th, &r);
   if (err != 0)
     {
       printf ("cannot join 1st thread: %d\n", err);
@@ -140,7 +130,7 @@ do_test (void)
       return 1;
     }
 
-  err = pthread_join (pthread_self (), NULL);
+  err = thread_join (pthread_self (), NULL);
   if (err == 0)
     {
       puts ("2nd circular join succeeded");
@@ -152,32 +142,19 @@ do_test (void)
       return 1;
     }
 
-  if (pthread_create (&th, NULL, tf2, (void *) pthread_self ()) != 0)
-    {
-      puts ("2nd create failed");
-      return 1;
-    }
+  th = xpthread_create (NULL, tf2, (void *) pthread_self ());
 
 #ifndef WAIT_IN_CHILD
   wait_code ();
 #endif
 
-  if (pthread_cancel (th) != 0)
-    {
-      puts ("cannot cancel 2nd thread");
-      return 1;
-    }
+  xpthread_cancel (th);
 
 #ifdef WAIT_IN_CHILD
-  e = pthread_barrier_wait (&b);
-  if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD)
-    {
-      printf ("%s: barrier_wait failed\n", __func__);
-      return 1;
-    }
+  xpthread_barrier_wait (&b);
 #endif
 
-  if (pthread_join (th, &r) != 0)
+  if (thread_join (th, &r) != 0)
     {
       puts ("cannot join 2nd thread");
       return 1;
@@ -188,7 +165,7 @@ do_test (void)
       return 1;
     }
 
-  err = pthread_join (pthread_self (), NULL);
+  err = thread_join (pthread_self (), NULL);
   if (err == 0)
     {
       puts ("3rd circular join succeeded");
@@ -203,5 +180,4 @@ do_test (void)
   return 0;
 }
 
-#define TEST_FUNCTION do_test ()
-#include "../test-skeleton.c"
+#include <support/test-driver.c>