malloc: Call tcache destructor in arena_thread_freeres

It does not make sense to register separate cleanup functions for arena
and tcache since they're always going to be called together.  Call the
tcache cleanup function from within arena_thread_freeres since it at
least makes the order of those cleanups clear in the code.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>

diff --git a/ChangeLog b/ChangeLog
index d9222a58d2db919da3e880fe4a5eca8a5d1732bd..9a9efa54d4309a2d7eb35525de75fe6f1cd0e1ac 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2017-11-23  Florian Weimer  <fweimer@redhat.com>
+
+       * malloc/malloc.c (tcache_thread_shutdown): Rename from
+       tcache_thread_freeres.  Define for USE_TCACHE and !USE_TCACHE
+       alike.  Remove freeres marker.
+       * malloc/arena.c (arena_thread_freeres): Call
+       tcache_thread_shutdown.
+
 2017-11-23  Florian Weimer  <fweimer@redhat.com>
 
        [BZ #22459]

diff --git a/malloc/arena.c b/malloc/arena.c
index 85b985e193d513b633bd148b275515a29a710584..4d27e17c46aaba2ca5c84380b38a5aa1598a77e4 100644 (file)
--- a/malloc/arena.c
+++ b/malloc/arena.c
@@ -944,6 +944,11 @@ arena_get_retry (mstate ar_ptr, size_t bytes)
 static void __attribute__ ((section ("__libc_thread_freeres_fn")))
 arena_thread_freeres (void)
 {
+  /* Shut down the thread cache first.  This could deallocate data for
+     the thread arena, so do this before we put the arena on the free
+     list.  */
+  tcache_thread_shutdown ();
+
   mstate a = thread_arena;
   thread_arena = NULL;
 

diff --git a/malloc/malloc.c b/malloc/malloc.c
index 2999ac4d2f883df355dc25d4da15f2563a25bbd0..79f0e9eac7483b3fba19849a44029b5e8ba3bd33 100644 (file)
--- a/malloc/malloc.c
+++ b/malloc/malloc.c
@@ -1869,6 +1869,9 @@ void *weak_variable (*__memalign_hook)
   = memalign_hook_ini;
 void weak_variable (*__after_morecore_hook) (void) = NULL;
 
+/* This function is called from the arena shutdown hook, to free the
+   thread cache (if it exists).  */
+static void tcache_thread_shutdown (void);
 
 /* ------------------ Testing support ----------------------------------*/
 
@@ -2938,8 +2941,8 @@ tcache_get (size_t tc_idx)
   return (void *) e;
 }
 
-static void __attribute__ ((section ("__libc_thread_freeres_fn")))
-tcache_thread_freeres (void)
+static void
+tcache_thread_shutdown (void)
 {
   int i;
   tcache_perthread_struct *tcache_tmp = tcache;
@@ -2965,7 +2968,6 @@ tcache_thread_freeres (void)
 
   __libc_free (tcache_tmp);
 }
-text_set_element (__libc_thread_subfreeres, tcache_thread_freeres);
 
 static void
 tcache_init(void)
@@ -3002,13 +3004,20 @@ tcache_init(void)
 
 }
 
-#define MAYBE_INIT_TCACHE() \
+# define MAYBE_INIT_TCACHE() \
   if (__glibc_unlikely (tcache == NULL)) \
     tcache_init();
 
-#else
-#define MAYBE_INIT_TCACHE()
-#endif
+#else  /* !USE_TCACHE */
+# define MAYBE_INIT_TCACHE()
+
+static void
+tcache_thread_shutdown (void)
+{
+  /* Nothing to do if there is no thread cache.  */
+}
+
+#endif /* !USE_TCACHE  */
 
 void *
 __libc_malloc (size_t bytes)