This is the mail archive of the
libc-alpha@sources.redhat.com
mailing list for the glibc project.
Re: Inefficient ia64 system call implementation in glibc
- From: David Mosberger <davidm at napali dot hpl dot hp dot com>
- To: Andreas Schwab <schwab at suse dot de>
- Cc: "Jim Hull" <jim dot hull at hp dot com>,"'GNU C Library'" <libc-alpha at sources dot redhat dot com>,"'linux ia64 kernel'" <linux-ia64 at vger dot kernel dot org>
- Date: Mon, 22 Sep 2003 14:25:36 -0700
- Subject: Re: Inefficient ia64 system call implementation in glibc
- References: <00f401c37f06$4af075f0$f463f40f@jh733133><jepthvk40p.fsf@sykes.suse.de>
- Reply-to: davidm at hpl dot hp dot com
>>>>> On Sat, 20 Sep 2003 15:01:26 +0200, Andreas Schwab <schwab@suse.de> said:
Andreas> "Jim Hull" <jim.hull@hp.com> writes:
>> But my real issue with the performance of this code is not with
>> sign-extend or the scheduling these instructions, it's with the
>> break instruction. I may be mistaken, but hasn't it been many
>> months since David Mosberger implemented all the kernel
>> infrastructure needed to support syscalls using the epc
>> instruction?
Andreas> It's only implemented in 2.6 so far.
No, the glibc support is completely orthogonal to the kernel support.
If glibc uses the new stubs on a kernel which doesn't support
kernel-entry via EPC, it will transparently fall back to using BREAK.
--david