[PATCH] Avoid using up static TLS surplus for optimizations [BZ #25051]

[Florian Weimer]

* Szabolcs Nagy:

> +void
> +_dl_static_tls_tunables_init (void)
> +{
> +  size_t nns, opt_tls;
> +
> +#if HAVE_TUNABLES
> +  nns = TUNABLE_GET (nns, size_t, NULL);
> +  opt_tls = TUNABLE_GET (optional_static_tls, size_t, NULL);
> +#else
> +  /* Default values of the tunables.  */
> +  nns = 4;
> +  opt_tls = 512;
> +#endif
> +  if (nns > DL_NNS)
> +    nns = DL_NNS;
> +  GL(dl_tls_static_optional) = opt_tls;
> +  GLRO(dl_tls_static_surplus) = ((nns - 1) * LIBC_IE_TLS
> +				 + nns * OTHER_IE_TLS
> +				 + opt_tls);
> +}

I think the default 4 is incompatible with elf/tst-manyaudit.  The test
doesn't check that all specified audit modules have been loaded.

I think we can automatically increase the number of namespaces based on
the count of audit modules.  This can be a follow-up patch, and I can
work on this.

Thanks,
Florian