Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > linux.kernel > #1592653
| From | Borislav Petkov <bp@suse.de> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | Re: Question Regarding ERMS memcpy |
| Date | 2017-03-05 01:40 +0100 |
| Message-ID | <thsno-mO-7@gated-at.bofh.it> (permalink) |
| References | (1 earlier) <thqEV-7AQ-5@gated-at.bofh.it> <thrKF-8kZ-13@gated-at.bofh.it> <thrKF-8kZ-11@gated-at.bofh.it> <ths41-gf-3@gated-at.bofh.it> <thsdH-jy-1@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
On Sat, Mar 04, 2017 at 04:23:17PM -0800, hpa@zytor.com wrote:
> What are the compilation flags? It may be that gcc still does TRT
> depending on this call site. I'd check what gcc6 or 7 generates,
> though.
Well, I don't think that matters: if you're building a kernel on one
machine to boot on another machine, the compiler can't know at build
time what the best MOVS* variant would be for the target machine. That's
why we're doing the alternatives patching at *boot* time.
However, if the size is small enough, the CALL/patch overhead would be
definitely too much.
Hmm, I wish we were able to say, "let gcc decide for small sizes and let
us do the patching for larger ones."
--
Regards/Gruss,
Boris.
SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
--
Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
Question Regarding ERMS memcpy Logan Gunthorpe <logang@deltatee.com> - 2017-03-04 22:20 +0100
Re: Question Regarding ERMS memcpy Borislav Petkov <bp@suse.de> - 2017-03-04 23:50 +0100
Re: Question Regarding ERMS memcpy hpa@zytor.com - 2017-03-05 01:00 +0100
Re: Question Regarding ERMS memcpy Borislav Petkov <bp@suse.de> - 2017-03-05 01:20 +0100
Re: Question Regarding ERMS memcpy hpa@zytor.com - 2017-03-05 01:30 +0100
Re: Question Regarding ERMS memcpy Borislav Petkov <bp@suse.de> - 2017-03-05 01:40 +0100
Re: Question Regarding ERMS memcpy hpa@zytor.com - 2017-03-05 02:00 +0100
Re: Question Regarding ERMS memcpy Borislav Petkov <bp@suse.de> - 2017-03-05 11:00 +0100
Re: Question Regarding ERMS memcpy Borislav Petkov <bp@suse.de> - 2017-03-05 12:20 +0100
Re: Question Regarding ERMS memcpy Borislav Petkov <bp@suse.de> - 2017-03-05 14:10 +0100
Re: Question Regarding ERMS memcpy Linus Torvalds <torvalds@linux-foundation.org> - 2017-03-05 20:30 +0100
Re: Question Regarding ERMS memcpy Borislav Petkov <bp@suse.de> - 2017-03-05 21:20 +0100
Re: Question Regarding ERMS memcpy Linus Torvalds <torvalds@linux-foundation.org> - 2017-03-05 21:20 +0100
Re: Question Regarding ERMS memcpy Logan Gunthorpe <logang@deltatee.com> - 2017-03-06 08:10 +0100
Re: Question Regarding ERMS memcpy "H. Peter Anvin" <hpa@zytor.com> - 2017-03-06 08:40 +0100
Re: Question Regarding ERMS memcpy Logan Gunthorpe <logang@deltatee.com> - 2017-03-06 18:50 +0100
Re: Question Regarding ERMS memcpy hpa@zytor.com - 2017-03-06 20:10 +0100
Re: Question Regarding ERMS memcpy Borislav Petkov <bp@suse.de> - 2017-03-06 14:40 +0100
Re: Question Regarding ERMS memcpy hpa@zytor.com - 2017-03-06 14:50 +0100
Re: Question Regarding ERMS memcpy Borislav Petkov <bp@suse.de> - 2017-03-06 15:10 +0100
Re: Question Regarding ERMS memcpy Logan Gunthorpe <logang@deltatee.com> - 2017-03-05 06:00 +0100
Re: Question Regarding ERMS memcpy Borislav Petkov <bp@suse.de> - 2017-03-05 11:00 +0100
csiph-web