svn commit: r282948 - head/lib/libthr/thread

[Rui Paulo]

On Friday 15 May 2015 08:40:17 Konstantin Belousov wrote:
> Author: kib
> Date: Fri May 15 08:40:17 2015
> New Revision: 282948
> URL: https://svnweb.freebsd.org/changeset/base/282948
> 
> Log:
>   Some third-party malloc(3) implementations use pthread_setspecific(3)
>   to handle per-thread information.  Since our pthread_setspecific()
>   implementation calls calloc(3) to allocate per-thread specific data
>   storage, things get complicated.
> 
>   Switch the allocator to use bare mmap(2).  There is some loss of the
>   allocated page, since e.g. on amd64, PTHREAD_KEYS_MAX * sizeof(struct
>   pthread_specific_elem) is 3K (it actually spans whole page due to
>   padding), but I believe it is more acceptable than additional code for
>   specialized allocator().
> 
>   The alternatives would either to make the specific data array be part of
>   the struct thread, or use internal bindings to call the libc malloc,
>   avoiding interposing.
> 
>   Also do the style pass over the thr_spec.c, esp. simplify the
>   conditionals nesting by returning early when an error detected.
>   Remove trivial comments.
> 
>   Found by:	yuri at rawbw.com
>   PR:	200138
>   Sponsored by:	The FreeBSD Foundation
>   MFC after:	2 weeks

Thanks!  I think umem might be affected as well.

-- 
Rui Paulo