On Tue, 7 Feb 2012 21:09:00 -0800 "H. Peter Anvin" <hpa@xxxxxxxxx> wrote: > From: "H. Peter Anvin" <hpa@xxxxxxxxx> > > Change the s390 architecture to use <asm-generic/posix_types.h>. > > Signed-off-by: H. Peter Anvin <hpa@xxxxxxxxx> > Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> > Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx> > Cc: <linux390@xxxxxxxxxx> > --- > arch/s390/include/asm/posix_types.h | 70 +++++------------------------------ > 1 files changed, 10 insertions(+), 60 deletions(-) I carefully checked the conversion and came to the conclusion that the new type definitions are equivalent to the old ones. The code compiles fine with the patches applied and the kernel boots. What I don't like is the conversion of __FD_ZERO. The new definition creates this code sequence: 0: a7 19 00 00 lghi %r1,0 4: e3 10 20 00 00 24 stg %r1,0(%r2) a: e3 10 20 08 00 24 stg %r1,8(%r2) 10: e3 10 20 10 00 24 stg %r1,16(%r2) 16: e3 10 20 18 00 24 stg %r1,24(%r2) 1c: e3 10 20 20 00 24 stg %r1,32(%r2) 22: e3 10 20 28 00 24 stg %r1,40(%r2) 28: e3 10 20 30 00 24 stg %r1,48(%r2) 2e: e3 10 20 38 00 24 stg %r1,56(%r2) 34: e3 10 20 40 00 24 stg %r1,64(%r2) 3a: e3 10 20 48 00 24 stg %r1,72(%r2) 40: e3 10 20 50 00 24 stg %r1,80(%r2) 46: e3 10 20 58 00 24 stg %r1,88(%r2) 4c: e3 10 20 60 00 24 stg %r1,96(%r2) 52: e3 10 20 68 00 24 stg %r1,104(%r2) 58: e3 10 20 70 00 24 stg %r1,112(%r2) 5e: e3 10 20 78 00 24 stg %r1,120(%r2) the old code used to be just a single instruction: 0: d7 7f 20 00 20 00 xc 0(128,%r2),0(%r2) That is quite a difference in code length. The execution speed should be almost the same though. -- blue skies, Martin. "Reality continues to ruin my life." - Calvin. -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
