[PATCH] Add GLIBC_PTHREAD_ELISION_ENABLE tunable

[Kalle Olavi Niemitalo]

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

>    int elision_available = (GLRO (dl_hwcap) & HWCAP_S390_TE) ? 1 : 0;
>  
> +  /* Check environment to see if we should disable LE.  */
> +  for (; *environ != NULL; environ++)
> +    if (strcmp (*environ, "GLIBC_PTHREAD_ELISION_ENABLE=no") == 0)
> +      __pthread_force_elision = 0;
> +
>    __pthread_force_elision = __libc_enable_secure ? 0 : elision_available;

This does not make sense, any value assigned to
__pthread_force_elision in the loop will be overwritten without
reading after the loop.