This is the mail archive of the
libc-alpha@sources.redhat.com
mailing list for the glibc project.
Re: Changed shared library loading strategy on PPC, why?
On Monday 18 June 2001 10:29, Andreas Jaeger wrote:
> Franz Sirl <Franz.Sirl-kernel@lauterbach.com> writes:
> > Hi,
> >
> > it seems someone changed the library loading strategy on PPC, which
> > certainly has a performance impact. So I would like to know why this
> > had been done and if it was done on purpose at all.
> >
> >
> > On PPC before the change the address scheme was like that:
> >
> > executable at 0x10000000
> > shared lib first load below that, and if that space runs out, loading
> > continues below 0x70000000.
> >
> >
> > Now, it seems that loading starts immediately below 0x70000000,
> > leaving the space with optimal relocations below 0x10000000 unused.
>
> Are you sure that this is not a "feature" of a new kernel? The kernel
> allocates the mmaped areas for glibc.
Yes, I rechecked with old glibc rpms I have lying around and that was
introduced somewhere between May 18 and Jun 6. I'm suspecting this patch:
2001-05-21 Jakub Jelinek <jakub@redhat.com>
* elf/rtld.c (dl_main): Compute l_map_end for the main program.
* elf/dl-sym.c (_dl_sym): Don't check for l_addr == 0.
If match == _dl_loaded, caller can still come from the main program.
(_dl_vsym): Likewise.
* elf/dl-open.c (dl_open_worker): Don't check for l_addr == 0.
* elf/dl-error.c (_dl_signal_error): Change NULL objname into "".
* elf/restest2.c: New test.
* elf/Makefile (tests): Add restest2.
(restest2, LDFLAGS-restest2): Add rules.
Jakub, can you comment on this? Also you did nearly all of the recent changes
in elf/, so it maybe obvious to you what's going on here.
Franz.