htl: Move thread table to ld.so

The next commit is going to introduce a new implementation of
THREAD_GSCOPE_WAIT which needs to access the list of threads.
Since it must be usable from the dynamic laoder, we have to move
the symbols for the list of threads into the loader.

Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20210915171110.226187-2-bugaevc@gmail.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>

1 files changed, 20 insertions, 30 deletions

diff --git a/htl/pt-alloc.c b/htl/pt-alloc.c
index acc67f2711..f6e783be10 100644
--- a/htl/pt-alloc.c
+++ b/htl/pt-alloc.c
@@ -28,19 +28,9 @@
    of the threads functions "shall fail" if "No thread could be found
    corresponding to that specified by the given thread ID."  */
 
-/* Thread ID lookup table.  */
-struct __pthread **__pthread_threads;
-
 /* The size of the thread ID lookup table.  */
 int __pthread_max_threads;
 
-/* The total number of thread IDs currently in use, or on the list of
-   available thread IDs.  */
-int __pthread_num_threads;
-
-/* A lock for the table, and the other variables above.  */
-pthread_rwlock_t __pthread_threads_lock;
-
 /* List of thread structures corresponding to free thread IDs.  */
 struct __pthread *__pthread_free_threads;
 pthread_mutex_t __pthread_free_threads_lock;
@@ -132,25 +122,25 @@ __pthread_alloc (struct __pthread **pthread)
     }
 
 retry:
-  __pthread_rwlock_wrlock (&__pthread_threads_lock);
+  __libc_rwlock_wrlock (GL (dl_pthread_threads_lock));
 
-  if (__pthread_num_threads < __pthread_max_threads)
+  if (GL (dl_pthread_num_threads) < __pthread_max_threads)
     {
       /* We have a free slot.  Use the slot number plus one as the
          thread ID for the new thread.  */
-      new->thread = 1 + __pthread_num_threads++;
-      __pthread_threads[new->thread - 1] = NULL;
+      new->thread = 1 + GL (dl_pthread_num_threads)++;
+      GL (dl_pthread_threads)[new->thread - 1] = NULL;
 
-      __pthread_rwlock_unlock (&__pthread_threads_lock);
+      __libc_rwlock_unlock (GL (dl_pthread_threads_lock));
 
       *pthread = new;
       return 0;
     }
 #ifdef PTHREAD_THREADS_MAX
-  else if (__pthread_num_threads >= PTHREAD_THREADS_MAX)
+  else if (GL (dl_pthread_num_threads) >= PTHREAD_THREADS_MAX)
     {
       /* We have reached the limit on the number of threads per process.  */
-      __pthread_rwlock_unlock (&__pthread_threads_lock);
+      __libc_rwlock_unlock (GL (dl_pthread_threads_lock));
 
       free (new);
       return EAGAIN;
@@ -162,7 +152,7 @@ retry:
      memory allocation, since that's a potentially blocking operation.  */
   max_threads = __pthread_max_threads;
 
-  __pthread_rwlock_unlock (&__pthread_threads_lock);
+  __libc_rwlock_unlock (GL (dl_pthread_threads_lock));
 
   /* Allocate a new lookup table that's twice as large.  */
   new_max_threads
@@ -174,13 +164,13 @@ retry:
       return ENOMEM;
     }
 
-  __pthread_rwlock_wrlock (&__pthread_threads_lock);
+  __libc_rwlock_wrlock (GL (dl_pthread_threads_lock));
 
   /* Check if nobody else has already enlarged the table.  */
   if (max_threads != __pthread_max_threads)
     {
       /* Yep, they did.  */
-      __pthread_rwlock_unlock (&__pthread_threads_lock);
+      __libc_rwlock_unlock (GL (dl_pthread_threads_lock));
 
       /* Free the newly allocated table and try again to allocate a slot.  */
       free (threads);
@@ -188,22 +178,22 @@ retry:
     }
 
   /* Copy over the contents of the old table.  */
-  memcpy (threads, __pthread_threads,
+  memcpy (threads, GL (dl_pthread_threads),
 	  __pthread_max_threads * sizeof (struct __pthread *));
 
   /* Save the location of the old table.  We want to deallocate its
      storage after we released the lock.  */
-  old_threads = __pthread_threads;
+  old_threads = GL (dl_pthread_threads);
 
   /* Replace the table with the new one.  */
   __pthread_max_threads = new_max_threads;
-  __pthread_threads = threads;
+  GL (dl_pthread_threads) = threads;
 
   /* And allocate ourselves one of the newly created slots.  */
-  new->thread = 1 + __pthread_num_threads++;
-  __pthread_threads[new->thread - 1] = NULL;
+  new->thread = 1 + GL (dl_pthread_num_threads)++;
+  GL (dl_pthread_threads)[new->thread - 1] = NULL;
 
-  __pthread_rwlock_unlock (&__pthread_threads_lock);
+  __libc_rwlock_unlock (GL (dl_pthread_threads_lock));
 
   free (old_threads);
 
@@ -217,10 +207,10 @@ __pthread_init_static_tls (struct link_map *map)
 {
   int i;
 
-  __pthread_rwlock_wrlock (&__pthread_threads_lock);
-  for (i = 0; i < __pthread_num_threads; ++i)
+  __libc_rwlock_wrlock (GL (dl_pthread_threads_lock));
+  for (i = 0; i < GL (dl_pthread_num_threads); ++i)
     {
-      struct __pthread *t = __pthread_threads[i];
+      struct __pthread *t = GL (dl_pthread_threads)[i];
 
       if (t == NULL)
 	continue;
@@ -237,5 +227,5 @@ __pthread_init_static_tls (struct link_map *map)
       memset (__mempcpy (dest, map->l_tls_initimage, map->l_tls_initimage_size),
 	      '\0', map->l_tls_blocksize - map->l_tls_initimage_size);
     }
-  __pthread_rwlock_unlock (&__pthread_threads_lock);
+  __libc_rwlock_unlock (GL (dl_pthread_threads_lock));
 }