diff mbox series

[02/13] nptl: Remove futex_wait_cancelable

Message ID 20201123195256.3336217-2-adhemerval.zanella@linaro.org
State New
Headers show
Series [01/13] linux: Remove unused internal futex functions | expand

Commit Message

Adhemerval Zanella Nov. 23, 2020, 7:52 p.m. UTC
It is used solely on __pthread_cond_wait_common and the call can be
replaced by a __futex_abstimed_wait_cancelable64 one.

Checked on x86_64-linux-gnu and i686-linux-gnu.
---
 nptl/pthread_cond_wait.c      | 22 ++--------------------
 sysdeps/nptl/futex-internal.h | 29 -----------------------------
 2 files changed, 2 insertions(+), 49 deletions(-)

Comments

Lukasz Majewski Nov. 24, 2020, 6:01 p.m. UTC | #1
Hi Adhemerval,

> It is used solely on __pthread_cond_wait_common and the call can be
> replaced by a __futex_abstimed_wait_cancelable64 one.
> 
> Checked on x86_64-linux-gnu and i686-linux-gnu.
> ---
>  nptl/pthread_cond_wait.c      | 22 ++--------------------
>  sysdeps/nptl/futex-internal.h | 29 -----------------------------
>  2 files changed, 2 insertions(+), 49 deletions(-)
> 
> diff --git a/nptl/pthread_cond_wait.c b/nptl/pthread_cond_wait.c
> index 7d158d553f..685dbca32f 100644
> --- a/nptl/pthread_cond_wait.c
> +++ b/nptl/pthread_cond_wait.c
> @@ -501,26 +501,8 @@ __pthread_cond_wait_common (pthread_cond_t
> *cond, pthread_mutex_t *mutex, cbuffer.private = private;
>  	  __pthread_cleanup_push (&buffer,
> __condvar_cleanup_waiting, &cbuffer); 
> -	  if (abstime == NULL)
> -	    {
> -	      /* Block without a timeout.  */
> -	      err = futex_wait_cancelable (
> -		  cond->__data.__g_signals + g, 0, private);
> -	    }
> -	  else
> -	    {
> -	      /* Block, but with a timeout.
> -		 Work around the fact that the kernel rejects
> negative timeout
> -		 values despite them being valid.  */
> -	      if (__glibc_unlikely (abstime->tv_sec < 0))
> -	        err = ETIMEDOUT;
> -	      else
> -		{
> -		  err = __futex_abstimed_wait_cancelable64
> -                    (cond->__data.__g_signals + g, 0, clockid,
> abstime,
> -                     private);
> -		}
> -	    }
> +	  err = __futex_abstimed_wait_cancelable64 (
> +	    cond->__data.__g_signals + g, 0, clockid, abstime,
> private); 

The __futex_abstimed_wait_cancelable64 can handle NULL abstime. Thanks
for cleaning this up :-).

>  	  __pthread_cleanup_pop (&buffer, 0);
>  
> diff --git a/sysdeps/nptl/futex-internal.h
> b/sysdeps/nptl/futex-internal.h index 21e3b74be6..96d1318091 100644
> --- a/sysdeps/nptl/futex-internal.h
> +++ b/sysdeps/nptl/futex-internal.h
> @@ -177,35 +177,6 @@ futex_wait_simple (unsigned int *futex_word,
> unsigned int expected, ignore_value (futex_wait (futex_word,
> expected, private)); }
>  
> -
> -/* Like futex_wait but is a POSIX cancellation point.  */
> -static __always_inline int
> -futex_wait_cancelable (unsigned int *futex_word, unsigned int
> expected,
> -		       int private)
> -{
> -  int oldtype;
> -  oldtype = __pthread_enable_asynccancel ();
> -  int err = lll_futex_timed_wait (futex_word, expected, NULL,
> private);
> -  __pthread_disable_asynccancel (oldtype);
> -  switch (err)
> -    {
> -    case 0:
> -    case -EAGAIN:
> -    case -EINTR:
> -      return -err;
> -
> -    case -ETIMEDOUT: /* Cannot have happened as we provided no
> timeout.  */
> -    case -EFAULT: /* Must have been caused by a glibc or application
> bug.  */
> -    case -EINVAL: /* Either due to wrong alignment or due to the
> timeout not
> -		     being normalized.  Must have been caused by a
> glibc or
> -		     application bug.  */
> -    case -ENOSYS: /* Must have been caused by a glibc bug.  */
> -    /* No other errors are documented at this time.  */
> -    default:
> -      futex_fatal_error ();
> -    }
> -}
> -
>  /* Like futex_wait, but will eventually time out (i.e., stop being
>     blocked) after the duration of time provided (i.e., RELTIME) has
>     passed.  The caller must provide a normalized RELTIME.  RELTIME
> can also

Reviewed-by: Lukasz Majewski <lukma@denx.de>


Best regards,

Lukasz Majewski

--

DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-59 Fax: (+49)-8142-66989-80 Email: lukma@denx.de
diff mbox series

Patch

diff --git a/nptl/pthread_cond_wait.c b/nptl/pthread_cond_wait.c
index 7d158d553f..685dbca32f 100644
--- a/nptl/pthread_cond_wait.c
+++ b/nptl/pthread_cond_wait.c
@@ -501,26 +501,8 @@  __pthread_cond_wait_common (pthread_cond_t *cond, pthread_mutex_t *mutex,
 	  cbuffer.private = private;
 	  __pthread_cleanup_push (&buffer, __condvar_cleanup_waiting, &cbuffer);
 
-	  if (abstime == NULL)
-	    {
-	      /* Block without a timeout.  */
-	      err = futex_wait_cancelable (
-		  cond->__data.__g_signals + g, 0, private);
-	    }
-	  else
-	    {
-	      /* Block, but with a timeout.
-		 Work around the fact that the kernel rejects negative timeout
-		 values despite them being valid.  */
-	      if (__glibc_unlikely (abstime->tv_sec < 0))
-	        err = ETIMEDOUT;
-	      else
-		{
-		  err = __futex_abstimed_wait_cancelable64
-                    (cond->__data.__g_signals + g, 0, clockid, abstime,
-                     private);
-		}
-	    }
+	  err = __futex_abstimed_wait_cancelable64 (
+	    cond->__data.__g_signals + g, 0, clockid, abstime, private);
 
 	  __pthread_cleanup_pop (&buffer, 0);
 
diff --git a/sysdeps/nptl/futex-internal.h b/sysdeps/nptl/futex-internal.h
index 21e3b74be6..96d1318091 100644
--- a/sysdeps/nptl/futex-internal.h
+++ b/sysdeps/nptl/futex-internal.h
@@ -177,35 +177,6 @@  futex_wait_simple (unsigned int *futex_word, unsigned int expected,
   ignore_value (futex_wait (futex_word, expected, private));
 }
 
-
-/* Like futex_wait but is a POSIX cancellation point.  */
-static __always_inline int
-futex_wait_cancelable (unsigned int *futex_word, unsigned int expected,
-		       int private)
-{
-  int oldtype;
-  oldtype = __pthread_enable_asynccancel ();
-  int err = lll_futex_timed_wait (futex_word, expected, NULL, private);
-  __pthread_disable_asynccancel (oldtype);
-  switch (err)
-    {
-    case 0:
-    case -EAGAIN:
-    case -EINTR:
-      return -err;
-
-    case -ETIMEDOUT: /* Cannot have happened as we provided no timeout.  */
-    case -EFAULT: /* Must have been caused by a glibc or application bug.  */
-    case -EINVAL: /* Either due to wrong alignment or due to the timeout not
-		     being normalized.  Must have been caused by a glibc or
-		     application bug.  */
-    case -ENOSYS: /* Must have been caused by a glibc bug.  */
-    /* No other errors are documented at this time.  */
-    default:
-      futex_fatal_error ();
-    }
-}
-
 /* Like futex_wait, but will eventually time out (i.e., stop being
    blocked) after the duration of time provided (i.e., RELTIME) has
    passed.  The caller must provide a normalized RELTIME.  RELTIME can also