Re: [PATCH 06/13] nptl: Eliminate __pthread_multiple_threads

[Carlos O'Donell <carlos@redhat.com>]

On 5/6/21 2:10 PM, Florian Weimer via Libc-alpha wrote:
> It is no longer needed after the SINGLE_THREADED_P consolidation.

Yup. LGTM.

Tested on x86_64 and i686 without regression.

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

> ---
>  nptl/allocatestack.c  | 4 ++--
>  nptl/pthreadP.h       | 7 -------
>  nptl/pthread_cancel.c | 2 +-
>  nptl/vars.c           | 7 -------
>  4 files changed, 3 insertions(+), 17 deletions(-)
> 
> diff --git a/nptl/allocatestack.c b/nptl/allocatestack.c
> index 059786192e..88c49f8154 100644
> --- a/nptl/allocatestack.c
> +++ b/nptl/allocatestack.c
> @@ -477,7 +477,7 @@ allocate_stack (const struct pthread_attr *attr, struct pthread **pdp,
>        /* This is at least the second thread.  */
>        pd->header.multiple_threads = 1;
>  #ifndef TLS_MULTIPLE_THREADS_IN_TCB
> -      __pthread_multiple_threads = __libc_multiple_threads = 1;
> +      __libc_multiple_threads = 1;
>  #endif
>  
>  #ifdef NEED_DL_SYSINFO
> @@ -598,7 +598,7 @@ allocate_stack (const struct pthread_attr *attr, struct pthread **pdp,
>  	  /* This is at least the second thread.  */
>  	  pd->header.multiple_threads = 1;
>  #ifndef TLS_MULTIPLE_THREADS_IN_TCB
> -	  __pthread_multiple_threads = __libc_multiple_threads = 1;
> +	  __libc_multiple_threads = 1;
>  #endif
>  
>  #ifdef NEED_DL_SYSINFO
> diff --git a/nptl/pthreadP.h b/nptl/pthreadP.h
> index dd6d6c6342..8ab247f977 100644
> --- a/nptl/pthreadP.h
> +++ b/nptl/pthreadP.h
> @@ -370,13 +370,6 @@ extern unsigned long int *__fork_generation_pointer attribute_hidden;
>  /* Register the generation counter in the libpthread with the libc.  */
>  extern void __libc_pthread_init (void (*reclaim) (void));
>  
> -#ifndef TLS_MULTIPLE_THREADS_IN_TCB
> -/* Variable set to a nonzero value either if more than one thread runs or ran,
> -   or if a single-threaded process is trying to cancel itself.  See
> -   nptl/descr.h for more context on the single-threaded process case.  */
> -extern int __pthread_multiple_threads attribute_hidden;
> -#endif
> -
>  extern size_t __pthread_get_minstack (const pthread_attr_t *attr);
>  
>  /* Namespace save aliases.  */
> diff --git a/nptl/pthread_cancel.c b/nptl/pthread_cancel.c
> index 2cab8f0a34..fd04bedf6c 100644
> --- a/nptl/pthread_cancel.c
> +++ b/nptl/pthread_cancel.c
> @@ -90,7 +90,7 @@ __pthread_cancel (pthread_t th)
>  	   points get executed.  */
>  	THREAD_SETMEM (THREAD_SELF, header.multiple_threads, 1);
>  #ifndef TLS_MULTIPLE_THREADS_IN_TCB
> -	__pthread_multiple_threads = __libc_multiple_threads = 1;
> +	__libc_multiple_threads = 1;
>  #endif
>      }
>    /* Mark the thread as canceled.  This has to be done
> diff --git a/nptl/vars.c b/nptl/vars.c
> index 8de30856b8..03a6cc84be 100644
> --- a/nptl/vars.c
> +++ b/nptl/vars.c
> @@ -26,10 +26,3 @@ union pthread_attr_transparent __default_pthread_attr attribute_hidden;
>  
>  /* Mutex protecting __default_pthread_attr.  */
>  int __default_pthread_attr_lock = LLL_LOCK_INITIALIZER;
> -
> -#ifndef TLS_MULTIPLE_THREADS_IN_TCB
> -/* Variable set to a nonzero value either if more than one thread runs or ran,
> -   or if a single-threaded process is trying to cancel itself.  See
> -   nptl/descr.h for more context on the single-threaded process case.  */
> -int __pthread_multiple_threads attribute_hidden;
> -#endif
> 


-- 
Cheers,
Carlos.