Re: [PATCH v8 06/10] Simplify __malloc_initialized

[Carlos O'Donell via Libc-alpha <libc-alpha@sourceware.org>]

On 7/13/21 3:38 AM, Siddhesh Poyarekar wrote:
> Now that mcheck no longer needs to check __malloc_initialized (and no
> other third party hook can since the symbol is not exported), make the
> variable boolean and static so that it is used strictly within malloc.

OK for 2.34.

Tested without regression on x86_64 and i686.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>

> ---
>  include/malloc.h |  6 ------
>  malloc/arena.c   | 12 ++++++------
>  malloc/malloc.c  | 24 ++++++++++++------------
>  3 files changed, 18 insertions(+), 24 deletions(-)
> 
> diff --git a/include/malloc.h b/include/malloc.h
> index b77761f74d..f9c9610548 100644
> --- a/include/malloc.h
> +++ b/include/malloc.h
> @@ -5,12 +5,6 @@
>  # ifndef _ISOMAC
>  #  include <rtld-malloc.h>
>  
> -/* In the GNU libc we rename the global variable
> -   `__malloc_initialized' to `__libc_malloc_initialized'.  */
> -#define __malloc_initialized __libc_malloc_initialized
> -/* Nonzero if the malloc is already initialized.  */
> -extern int __malloc_initialized attribute_hidden;

OK.

> -
>  struct malloc_state;
>  typedef struct malloc_state *mstate;
>  
> diff --git a/malloc/arena.c b/malloc/arena.c
> index 9111b49589..840426f9fb 100644
> --- a/malloc/arena.c
> +++ b/malloc/arena.c
> @@ -97,7 +97,7 @@ static mstate free_list;
>  __libc_lock_define_initialized (static, list_lock);
>  
>  /* Already initialized? */
> -int __malloc_initialized = -1;
> +static bool __malloc_initialized = false;

OK.

>  
>  /**************************************************************************/
>  
> @@ -143,7 +143,7 @@ int __malloc_initialized = -1;
>  void
>  __malloc_fork_lock_parent (void)
>  {
> -  if (__malloc_initialized < 1)
> +  if (!__malloc_initialized)

OK.

>      return;
>  
>    /* We do not acquire free_list_lock here because we completely
> @@ -163,7 +163,7 @@ __malloc_fork_lock_parent (void)
>  void
>  __malloc_fork_unlock_parent (void)
>  {
> -  if (__malloc_initialized < 1)
> +  if (!__malloc_initialized)
>      return;
>  
>    for (mstate ar_ptr = &main_arena;; )
> @@ -179,7 +179,7 @@ __malloc_fork_unlock_parent (void)
>  void
>  __malloc_fork_unlock_child (void)
>  {
> -  if (__malloc_initialized < 1)
> +  if (!__malloc_initialized)
>      return;
>  
>    /* Push all arenas to the free list, except thread_arena, which is
> @@ -286,10 +286,10 @@ static void tcache_key_initialize (void);
>  static void
>  ptmalloc_init (void)
>  {
> -  if (__malloc_initialized >= 0)
> +  if (__malloc_initialized)
>      return;
>  
> -  __malloc_initialized = 0;
> +  __malloc_initialized = true;
>  
>  #if USE_TCACHE
>    tcache_key_initialize ();
> diff --git a/malloc/malloc.c b/malloc/malloc.c
> index cf71314b2b..ed0316e690 100644
> --- a/malloc/malloc.c
> +++ b/malloc/malloc.c
> @@ -3195,7 +3195,7 @@ __libc_malloc (size_t bytes)
>    _Static_assert (PTRDIFF_MAX <= SIZE_MAX / 2,
>                    "PTRDIFF_MAX is not more than half of SIZE_MAX");
>  
> -  if (__malloc_initialized < 0)
> +  if (!__malloc_initialized)
>      ptmalloc_init ();
>  #if USE_TCACHE
>    /* int_free also calls request2size, be careful to not pad twice.  */
> @@ -3308,7 +3308,7 @@ __libc_realloc (void *oldmem, size_t bytes)
>  
>    void *newp;             /* chunk to return */
>  
> -  if (__malloc_initialized < 0)
> +  if (!__malloc_initialized)
>      ptmalloc_init ();
>  
>  #if REALLOC_ZERO_BYTES_FREES
> @@ -3444,7 +3444,7 @@ libc_hidden_def (__libc_realloc)
>  void *
>  __libc_memalign (size_t alignment, size_t bytes)
>  {
> -  if (__malloc_initialized < 0)
> +  if (!__malloc_initialized)
>      ptmalloc_init ();
>  
>    void *address = RETURN_ADDRESS (0);
> @@ -3515,7 +3515,7 @@ libc_hidden_def (__libc_memalign)
>  void *
>  __libc_valloc (size_t bytes)
>  {
> -  if (__malloc_initialized < 0)
> +  if (!__malloc_initialized)
>      ptmalloc_init ();
>  
>    void *address = RETURN_ADDRESS (0);
> @@ -3526,7 +3526,7 @@ __libc_valloc (size_t bytes)
>  void *
>  __libc_pvalloc (size_t bytes)
>  {
> -  if (__malloc_initialized < 0)
> +  if (!__malloc_initialized)
>      ptmalloc_init ();
>  
>    void *address = RETURN_ADDRESS (0);
> @@ -3565,7 +3565,7 @@ __libc_calloc (size_t n, size_t elem_size)
>  
>    sz = bytes;
>  
> -  if (__malloc_initialized < 0)
> +  if (!__malloc_initialized)
>      ptmalloc_init ();
>  
>    MAYBE_INIT_TCACHE ();
> @@ -5022,7 +5022,7 @@ __malloc_trim (size_t s)
>  {
>    int result = 0;
>  
> -  if (__malloc_initialized < 0)
> +  if (!__malloc_initialized)
>      ptmalloc_init ();
>  
>    mstate ar_ptr = &main_arena;
> @@ -5157,7 +5157,7 @@ __libc_mallinfo2 (void)
>    struct mallinfo2 m;
>    mstate ar_ptr;
>  
> -  if (__malloc_initialized < 0)
> +  if (!__malloc_initialized)
>      ptmalloc_init ();
>  
>    memset (&m, 0, sizeof (m));
> @@ -5208,7 +5208,7 @@ __malloc_stats (void)
>    mstate ar_ptr;
>    unsigned int in_use_b = mp_.mmapped_mem, system_b = in_use_b;
>  
> -  if (__malloc_initialized < 0)
> +  if (!__malloc_initialized)
>      ptmalloc_init ();
>    _IO_flockfile (stderr);
>    int old_flags2 = stderr->_flags2;
> @@ -5377,7 +5377,7 @@ __libc_mallopt (int param_number, int value)
>    mstate av = &main_arena;
>    int res = 1;
>  
> -  if (__malloc_initialized < 0)
> +  if (!__malloc_initialized)
>      ptmalloc_init ();
>    __libc_lock_lock (av->mutex);
>  
> @@ -5595,7 +5595,7 @@ __posix_memalign (void **memptr, size_t alignment, size_t size)
>  {
>    void *mem;
>  
> -  if (__malloc_initialized < 0)
> +  if (!__malloc_initialized)
>      ptmalloc_init ();
>  
>    /* Test whether the SIZE argument is valid.  It must be a power of
> @@ -5639,7 +5639,7 @@ __malloc_info (int options, FILE *fp)
>  
>  
>  
> -  if (__malloc_initialized < 0)
> +  if (!__malloc_initialized)
>      ptmalloc_init ();
>  
>    fputs ("<malloc version=\"1\">\n", fp);
> 

OK.

-- 
Cheers,
Carlos.