Re: Questions about --with-alpha and --with-armeb configure flags

[Steve Grubb <sgrubb@redhat.com>]

On Monday, November 26, 2012 12:21:55 PM Miloslav Trmac wrote:
> ----- Original Message -----
> 
> > > If I understand correctly it's only adding arch detection and syscall
> > > tables to ausyscall. Why are these syscall table conditional?
> > 
> > To reduce the number of text relocations in libaudit. Libaudit links
> > against a number of applications and text relocations eats memory and
> > increases startup time.
> 
> Is that really an issue with the current code?  The gentab.c code was
> designed to avoid text relocations.

I guess not

# relinfo.pl /lib64/libaudit.so.1.0.0 
/lib64/libaudit.so.1.0.0: 45 relocations, 35 relative (77%), 60 PLT entries, 2 
for local syms (3%), 97 users

# relinfo.pl /home/sgrubb/working/BUILD/audit/lib/.libs/libaudit.so.1.0.0 
/home/sgrubb/working/BUILD/audit/lib/.libs/libaudit.so.1.0.0: 45 relocations, 
35 relative (77%), 56 PLT entries, 2 for local syms (3%), 0 users

However, it does trim about 14k off libaudit by not compiling these in.


> At least on x86_64 (which, true, is especially well-designed for this),
> there are no text relocations in libaudit nor libauparse, whether
> --with-alpha or --with-armeb are used or not.  In fact the number of
> relocations of any kind is exactly the same in both cases.
> 
> Any one care to retest this on a different architecture, e.t. 32-bit x86?
> 
> FWIW, at least the attached patch was necessary to build with --with-alpha
> --with-armeb.

Applied. Thanks.

-Steve