On 3/4/2017 5:51 PM, John Baldwin wrote:
On Saturday, March 04, 2017 03:49:52 PM Pedro Giffuni wrote:
Il giorno 04 mar 2017, alle ore 14:43, John Baldwin <j...@freebsd.org> ha
scritto:
On Saturday, March 04, 2017 10:52:46 AM Pedro Giffuni wrote:
On 03/04/17 10:32, Slawa Olhovchenkov wrote:
On Sat, Mar 04, 2017 at 03:04:17PM +0000, Pedro F. Giffuni wrote:
Author: pfg
Date: Sat Mar 4 15:04:17 2017
New Revision: 314669
URL: https://svnweb.freebsd.org/changeset/base/314669
Log:
Drop i486 from the default i386 GENERIC kernel configuration.
80486 production was stopped by Intel on September 2007. Dropping the 486
configuration option from the GENERIC kernel improves performance
slightly.
Removing I486_CPU is consistent at this time: we don't support any
processor without a FPU and the PC-98 arch, which frequently involved i486
CPUs, is also gone so we don't test such platforms anymore.
What is realy mean?
This means we don't do work-arounds that would be required for raw 486.
Instead we will use the 586 instructions by default.
This doesn't change that. The kernel already has runtime tests in place
for new things on 486 and later via cpuid.
Hmm ..then I am wondering if I effectively changed anything?
The only change is a 486 now panics on boot when it used to work fine. :-/
Nothing for other CPUs has changed.
Not much has been lost then.
FWIW, I have a "Pentium overdrive" somewhere in the basement which could
theoretically boot FreeBSD 12 but last I remember just rebuilding a
kernel was painful and the memory and HD limitations really make it a no-go.
The number came out from an old posting involving buildworld times, which I
can’t find now :(.
Things seem to have changed a lot: it was surely using GCC back then, I don’t
believe clang does much distinction about 486 at all.
BTW, does it make sense to keep i586 in the configuration still? Both i486 and
i586 were once removed but later re-instated in r205336.
If anything I'd probably say we should do what bde@ suggested and just
remove CPU class entirely (and act as if 486, 586, and 686 are always
defined).
In any case ... I won't MFC the change and if someone asks me to revert
it I will (I'd love to see a dmesg first ;) ).
Pedro.
_______________________________________________
svn-src-head@freebsd.org mailing list
https://lists.freebsd.org/mailman/listinfo/svn-src-head
To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
