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-rw-r--r--nptl/pthread_create.c419
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diff --git a/nptl/pthread_create.c b/nptl/pthread_create.c
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+/* Copyright (C) 2002 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <errno.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include "pthreadP.h"
+#include <hp-timing.h>
+#include <ldsodefs.h>
+
+#include <shlib-compat.h>
+
+
+/* Local function to start thread and handle cleanup.  */
+static int start_thread (void *arg);
+/* Similar version used when debugging.  */
+static int start_thread_debug (void *arg);
+
+
+/* Nozero if debugging mode is enabled.  */
+int __pthread_debug;
+
+/* Globally enabled events.  */
+td_thr_events_t __nptl_threads_events attribute_hidden;
+
+/* Pointer to descriptor with the last event.  */
+struct pthread *__nptl_last_event attribute_hidden;
+
+
+/* Code to allocate and deallocate a stack.  */
+#define DEFINE_DEALLOC
+#include "allocatestack.c"
+
+/* Code to create the thread.  */
+#include "createthread.c"
+
+
+/* Table of the key information.  */
+struct pthread_key_struct __pthread_keys[PTHREAD_KEYS_MAX];
+
+
+struct pthread *
+__find_in_stack_list (pd)
+     struct pthread *pd;
+{
+  list_t *entry;
+  struct pthread *result = NULL;
+
+  lll_lock (stack_cache_lock);
+
+  list_for_each (entry, &stack_used)
+    {
+      struct pthread *curp;
+
+      curp = list_entry (entry, struct pthread, header.data.list);
+      if (curp == pd)
+	{
+	  result = curp;
+	  break;
+	}
+    }
+
+  if (result == NULL)
+    list_for_each (entry, &__stack_user)
+      {
+	struct pthread *curp;
+
+	curp = list_entry (entry, struct pthread, header.data.list);
+	if (curp == pd)
+	  {
+	    result = curp;
+	    break;
+	  }
+      }
+
+  lll_unlock (stack_cache_lock);
+
+  return result;
+}
+
+
+/* Deallocate POSIX thread-local-storage.  */
+static void
+deallocate_tsd (struct pthread *pd)
+{
+  /* Maybe no data was ever allocated.  This happens often so we have
+     a flag for this.  */
+  if (pd->specific_used)
+    {
+      size_t round;
+      bool found_nonzero;
+
+      for (round = 0, found_nonzero = true;
+	   found_nonzero && round < PTHREAD_DESTRUCTOR_ITERATIONS;
+	   ++round)
+	{
+	  size_t cnt;
+	  size_t idx;
+
+	  for (cnt = idx = 0; cnt < PTHREAD_KEY_1STLEVEL_SIZE; ++cnt)
+	    if (pd->specific[cnt] != NULL)
+	      {
+		size_t inner;
+
+		for (inner = 0; inner < PTHREAD_KEY_2NDLEVEL_SIZE;
+		     ++inner, ++idx)
+		  {
+		    void *data = pd->specific[cnt][inner].data;
+
+		    if (data != NULL
+			/* Make sure the data corresponds to a valid
+			   key.  This test fails if the key was
+			   deallocated and also if it was
+			   re-allocated.  It is the user's
+			   responsibility to free the memory in this
+			   case.  */
+			&& (pd->specific[cnt][inner].seq
+			    == __pthread_keys[idx].seq)
+			/* It is not necessary to register a destructor
+			   function.  */
+			&& __pthread_keys[idx].destr != NULL)
+		      {
+			pd->specific[cnt][inner].data = NULL;
+			__pthread_keys[idx].destr (data);
+			found_nonzero = true;
+		      }
+		  }
+
+		if (cnt != 0)
+		  {
+		    /* The first block is allocated as part of the thread
+		       descriptor.  */
+		    free (pd->specific[cnt]);
+		    pd->specific[cnt] = NULL;
+		  }
+		else
+		  /* Clear the memory of the first block for reuse.  */
+		  memset (pd->specific[0], '\0',
+			  sizeof (struct pthread_key_data));
+	      }
+	    else
+	      idx += PTHREAD_KEY_1STLEVEL_SIZE;
+	}
+
+      pd->specific_used = false;
+    }
+}
+
+
+/* Deallocate a thread's stack after optionally making sure the thread
+   descriptor is still valid.  */
+void
+__free_tcb (struct pthread *pd)
+{
+  /* The thread is exiting now.  */
+  if (atomic_bit_test_set (&pd->cancelhandling, TERMINATED_BIT) == 0)
+    {
+      /* Remove the descriptor from the list.  */
+      if (DEBUGGING_P && __find_in_stack_list (pd) == NULL)
+	/* Something is really wrong.  The descriptor for a still
+	   running thread is gone.  */
+	abort ();
+
+      /* Run the destructor for the thread-local data.  */
+      deallocate_tsd (pd);
+
+      /* Queue the stack memory block for reuse and exit the process.  The
+	 kernel will signal via writing to the address returned by
+	 QUEUE-STACK when the stack is available.  */
+      __deallocate_stack (pd);
+    }
+}
+
+
+static int
+start_thread (void *arg)
+{
+  struct pthread *pd = (struct pthread *) arg;
+
+#if HP_TIMING_AVAIL
+  /* Remember the time when the thread was started.  */
+  hp_timing_t now;
+  HP_TIMING_NOW (now);
+  THREAD_SETMEM (pd, cpuclock_offset, now);
+#endif
+
+  /* This is where the try/finally block should be created.  For
+     compilers without that support we do use setjmp.  */
+  if (setjmp (pd->cancelbuf) == 0)
+    {
+      /* Run the code the user provided.  */
+      pd->result = pd->start_routine (pd->arg);
+    }
+
+
+  /* Report the death of the thread if this is wanted.  */
+  if (__builtin_expect (pd->report_events, 0))
+    {
+      /* See whether TD_DEATH is in any of the mask.  */
+      const int idx = __td_eventword (TD_DEATH);
+      const uint32_t mask = __td_eventmask (TD_DEATH);
+
+      if ((mask & (__nptl_threads_events.event_bits[idx]
+		   | pd->eventbuf.eventmask.event_bits[idx])) != 0)
+	{
+	  /* Yep, we have to signal the death.  Add the descriptor to
+	     the list but only if it is not already on it.  */
+	  if (pd->nextevent == NULL)
+	    {
+	      pd->eventbuf.eventnum = TD_DEATH;
+	      pd->eventbuf.eventdata = pd;
+
+	      do
+		pd->nextevent = __nptl_last_event;
+	      while (atomic_compare_and_exchange_acq (__nptl_last_event, pd,
+						      pd->nextevent) != 0);
+	    }
+
+	  /* Now call the function to signal the event.  */
+	  __nptl_death_event ();
+	}
+    }
+
+
+  /* The thread is exiting now.  */
+  atomic_bit_set (&pd->cancelhandling, EXITING_BIT);
+
+  /* If the thread is detached free the TCB.  */
+  if (IS_DETACHED (pd))
+    /* Free the TCB.  */
+    __free_tcb (pd);
+
+  /* We cannot call '_exit' here.  '_exit' will terminate the process.
+
+     The 'exit' implementation in the kernel will signal when the
+     process is really dead since 'clone' got passed the CLONE_CLEARTID
+     flag.  The 'tid' field in the TCB will be set to zero.
+
+     The exit code is zero since in case all threads exit by calling
+     'pthread_exit' the exit status must be 0 (zero).  */
+  __exit_thread_inline (0);
+
+  /* NOTREACHED */
+  return 0;
+}
+
+
+/* Just list start_thread but we do some more things needed for a run
+   with a debugger attached.  */
+static int
+start_thread_debug (void *arg)
+{
+  struct pthread *pd = (struct pthread *) arg;
+
+  /* Get the lock the parent locked to force synchronization.  */
+  lll_lock (pd->lock);
+  /* And give it up right away.  */
+  lll_unlock (pd->lock);
+
+  /* Now do the actual startup.  */
+  return start_thread (arg);
+}
+
+
+/* Default thread attributes for the case when the user does not
+   provide any.  */
+static const struct pthread_attr default_attr =
+  {
+    /* Just some value > 0 which gets rounded to the nearest page size.  */
+    .guardsize = 1,
+  };
+
+
+int
+__pthread_create_2_1 (newthread, attr, start_routine, arg)
+     pthread_t *newthread;
+     const pthread_attr_t *attr;
+     void *(*start_routine) (void *);
+     void *arg;
+{
+  STACK_VARIABLES;
+  const struct pthread_attr *iattr;
+  struct pthread *pd;
+  int err;
+
+  iattr = (struct pthread_attr *) attr;
+  if (iattr == NULL)
+    /* Is this the best idea?  On NUMA machines this could mean
+       accessing far-away memory.  */
+    iattr = &default_attr;
+
+  err = ALLOCATE_STACK (iattr, &pd);
+  if (err != 0)
+    /* Something went wrong.  Maybe a parameter of the attributes is
+       invalid or we could not allocate memory.  */
+    return err;
+
+
+  /* Initialize the TCB.  All initializations with zero should be
+     performed in 'get_cached_stack'.  This way we avoid doing this if
+     the stack freshly allocated with 'mmap'.  */
+
+  /* Reference to the TCB itself.  */
+  pd->header.data.self = pd;
+
+#ifdef TLS_TCB_AT_TP
+  /* Self-reference.  */
+  pd->header.data.tcb = pd;
+#endif
+
+  /* Store the address of the start routine and the parameter.  Since
+     we do not start the function directly the stillborn thread will
+     get the information from its thread descriptor.  */
+  pd->start_routine = start_routine;
+  pd->arg = arg;
+
+  /* Copy the thread attribute flags.  */
+  pd->flags = iattr->flags;
+
+  /* Initialize the field for the ID of the thread which is waiting
+     for us.  This is a self-reference in case the thread is created
+     detached.  */
+  pd->joinid = iattr->flags & ATTR_FLAG_DETACHSTATE ? pd : NULL;
+
+  /* The debug events are inherited from the parent.  */
+  pd->eventbuf = THREAD_SELF->eventbuf;
+
+
+  /* Determine scheduling parameters for the thread.
+     XXX How to determine whether scheduling handling is needed?  */
+  if (0 && attr != NULL)
+    {
+      if (iattr->flags & ATTR_FLAG_NOTINHERITSCHED)
+	{
+	  /* Use the scheduling parameters the user provided.  */
+	  pd->schedpolicy = iattr->schedpolicy;
+	  memcpy (&pd->schedparam, &iattr->schedparam,
+		  sizeof (struct sched_param));
+	}
+      else
+	{
+	  /* Just store the scheduling attributes of the parent.  */
+	  pd->schedpolicy = __sched_getscheduler (0);
+	  __sched_getparam (0, &pd->schedparam);
+	}
+    }
+
+  /* Pass the descriptor to the caller.  */
+  *newthread = (pthread_t) pd;
+
+  /* Start the thread.  */
+  err = create_thread (pd, STACK_VARIABLES_ARGS);
+  if (err != 0)
+    {
+      /* Something went wrong.  Free the resources.  */
+      __deallocate_stack (pd);
+      return err;
+    }
+
+  return 0;
+}
+versioned_symbol (libpthread, __pthread_create_2_1, pthread_create, GLIBC_2_1);
+
+
+#if SHLIB_COMPAT(libpthread, GLIBC_2_0, GLIBC_2_1)
+int
+__pthread_create_2_0 (newthread, attr, start_routine, arg)
+     pthread_t *newthread;
+     const pthread_attr_t *attr;
+     void *(*start_routine) (void *);
+     void *arg;
+{
+  /* The ATTR attribute is not really of type `pthread_attr_t *'.  It has
+     the old size and access to the new members might crash the program.
+     We convert the struct now.  */
+  struct pthread_attr new_attr;
+
+  if (attr != NULL)
+    {
+      struct pthread_attr *iattr = (struct pthread_attr *) attr;
+      size_t ps = __getpagesize ();
+
+      /* Copy values from the user-provided attributes.  */
+      new_attr.schedparam = iattr->schedparam;
+      new_attr.schedpolicy = iattr->schedpolicy;
+      new_attr.flags = iattr->flags;
+
+      /* Fill in default values for the fields not present in the old
+	 implementation.  */
+      new_attr.guardsize = ps;
+      new_attr.stackaddr = NULL;
+      new_attr.stacksize = 0;
+
+      /* We will pass this value on to the real implementation.  */
+      attr = (pthread_attr_t *) &new_attr;
+    }
+
+  return __pthread_create_2_1 (newthread, attr, start_routine, arg);
+}
+compat_symbol (libpthread, __pthread_create_2_0, pthread_create,
+	       GLIBC_2_0);
+#endif