Re: PR/49816 CVS commit: src/libexec/ld.elf_so

[yamt%netbsd.org@localhost (YAMAMOTO Takashi)]

> The following reply was made to PR lib/49816; it has been noted by GNATS.
> 
> From: Joerg Sonnenberger <joerg%britannica.bec.de@localhost>
> To: gnats-bugs%NetBSD.org@localhost
> Cc: lib-bug-people%netbsd.org@localhost, gnats-admin%netbsd.org@localhost,
> 	netbsd-bugs%netbsd.org@localhost, yamt%NetBSD.org@localhost
> Subject: Re: PR/49816 CVS commit: src/libexec/ld.elf_so
> Date: Mon, 6 Apr 2015 18:22:21 +0200
> 
>  On Mon, Apr 06, 2015 at 04:10:02PM +0000, YAMAMOTO Takashi wrote:
>  >  except that:
>  >  * _rtld_exclusive_exit doesn't use CAS
>  >  * this code is MI
>  >  
>  >  i agree that something like PTHREAD__ATOMIC_IS_MEMBAR
>  >  would be a nice optimization, though.
>  
>  So which platform are you worried about that doesn't have TSO and
>  doesn't implicit membars for CAS? I'm asking because the only reason
>  those changes should help your problem is if they massively penalize the
>  operation.

well, can you explain why _rtld_exclusive_exit is safe
without cas or barrier?

YAMAMOTO Takashi

>  
>  Joerg