nptl: Move __nptl_deallocate_tsd into libc

This prepares moving pthread_exit, and later the pthread_key_create
infrastructure.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

1 files changed, 112 insertions, 0 deletions

diff --git a/nptl/nptl_deallocate_tsd.c b/nptl/nptl_deallocate_tsd.c
new file mode 100644
index 0000000000..c665f4a08a
--- /dev/null
+++ b/nptl/nptl_deallocate_tsd.c
@@ -0,0 +1,112 @@
+/* Deallocation thread-specific data structures related to pthread_key_create.
+   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, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <pthreadP.h>
+
+/* Deallocate POSIX thread-local-storage.  */
+void
+__nptl_deallocate_tsd (void)
+{
+  struct pthread *self = THREAD_SELF;
+
+  /* Maybe no data was ever allocated.  This happens often so we have
+     a flag for this.  */
+  if (THREAD_GETMEM (self, specific_used))
+    {
+      size_t round;
+      size_t cnt;
+
+      round = 0;
+      do
+        {
+          size_t idx;
+
+          /* So far no new nonzero data entry.  */
+          THREAD_SETMEM (self, specific_used, false);
+
+          for (cnt = idx = 0; cnt < PTHREAD_KEY_1STLEVEL_SIZE; ++cnt)
+            {
+              struct pthread_key_data *level2;
+
+              level2 = THREAD_GETMEM_NC (self, specific, cnt);
+
+              if (level2 != NULL)
+                {
+                  size_t inner;
+
+                  for (inner = 0; inner < PTHREAD_KEY_2NDLEVEL_SIZE;
+                       ++inner, ++idx)
+                    {
+                      void *data = level2[inner].data;
+
+                      if (data != NULL)
+                        {
+                          /* Always clear the data.  */
+                          level2[inner].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.  */
+                          if (level2[inner].seq
+                              == __pthread_keys[idx].seq
+                              /* It is not necessary to register a destructor
+                                 function.  */
+                              && __pthread_keys[idx].destr != NULL)
+                            /* Call the user-provided destructor.  */
+                            __pthread_keys[idx].destr (data);
+                        }
+                    }
+                }
+              else
+                idx += PTHREAD_KEY_1STLEVEL_SIZE;
+            }
+
+          if (THREAD_GETMEM (self, specific_used) == 0)
+            /* No data has been modified.  */
+            goto just_free;
+        }
+      /* We only repeat the process a fixed number of times.  */
+      while (__builtin_expect (++round < PTHREAD_DESTRUCTOR_ITERATIONS, 0));
+
+      /* Just clear the memory of the first block for reuse.  */
+      memset (&THREAD_SELF->specific_1stblock, '\0',
+              sizeof (self->specific_1stblock));
+
+    just_free:
+      /* Free the memory for the other blocks.  */
+      for (cnt = 1; cnt < PTHREAD_KEY_1STLEVEL_SIZE; ++cnt)
+        {
+          struct pthread_key_data *level2;
+
+          level2 = THREAD_GETMEM_NC (self, specific, cnt);
+          if (level2 != NULL)
+            {
+              /* The first block is allocated as part of the thread
+                 descriptor.  */
+              free (level2);
+              THREAD_SETMEM_NC (self, specific, cnt, NULL);
+            }
+        }
+
+      THREAD_SETMEM (self, specific_used, false);
+    }
+}
+libc_hidden_def (__nptl_deallocate_tsd)