[PATCHv2 2/2] powerpc: Optimize lock elision for pthread_mutex_t

[Andreas Schwab]

"Paul E. Murphy" <murphyp@linux.vnet.ibm.com> writes:

> diff --git a/sysdeps/unix/sysv/linux/powerpc/elision-unlock.c b/sysdeps/unix/sysv/linux/powerpc/elision-unlock.c
> index f04c339..4307d44 100644
> --- a/sysdeps/unix/sysv/linux/powerpc/elision-unlock.c
> +++ b/sysdeps/unix/sysv/linux/powerpc/elision-unlock.c
> @@ -21,12 +21,20 @@
>  #include "htm.h"
>  
>  int
> -__lll_unlock_elision(int *lock, int pshared)
> +__lll_unlock_elision(int *lock, short *adapt_count, int pshared)
>  {
>    /* When the lock was free we're in a transaction.  */
>    if (*lock == 0)
>      __builtin_tend (0);
>    else
> +    {
>      lll_unlock ((*lock), pshared);
> +
> +    /* Update the adapt count AFTER completing the critical section.
> +       Doing this here prevents unneeded stalling when entering
> +       a critical section.  Saving about 8% runtime on P8.  */
> +    if (*adapt_count > 0)
> +      (*adapt_count)--;
> +    }

Wrong indentation.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."