From: Andi Kleen <ak@suse.de>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: linux-kernel@vger.kernel.org
Subject: [PATCH] Add CONFIG_X86_RUNTIME_XMM for 2.4.
Date: Mon, 8 Jan 2001 18:21:06 +0100 [thread overview]
Message-ID: <20010108182106.A11978@gruyere.muc.suse.de> (raw)
Hallo,
Currently there is no way to get the support for the SSE2 exceptions compiled in
without getting the P3 memory barriers too. The SSE2 exception code correctly
checks all feature flags, but the memory barriers do not. This patch adds a
CONFIG_X86_RUNTIME_XMM, which enables the SSE2 code, but not the barriers (because
it would be too expensive to check at every barrier, and the old barriers work fine
for now so runtime patching is probably not worth it)
ATM there is no way to select the CONFIG_X86_RUNTIME_FXSR directly as a
CPU configuration, the user needs to add a statement to config.in. In the long
run I suspect we'll just need a couple of "GENERIC" cpu templates which e.g.
contain X86_RUNTIME_FXSR or X86_RUNTIME_XMM. Currently no predefined CPU
is truly generic if you don't want reduced functionality.
Please consider for 2.4.0-ac5+
-Andi
--- linux-work/include/asm-i386/bugs.h-o Mon Jan 8 17:02:04 2001
+++ linux-work/include/asm-i386/bugs.h Mon Jan 8 17:30:29 2001
@@ -89,7 +89,7 @@
printk("done.\n");
}
#endif
-#ifdef CONFIG_X86_XMM
+#if defined(CONFIG_X86_XMM) || defined(CONFIG_X86_RUNTIME_XMM)
if (cpu_has_xmm) {
printk(KERN_INFO "Enabling unmasked SIMD FPU exception support... ");
set_in_cr4(X86_CR4_OSXMMEXCPT);
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
Please read the FAQ at http://www.tux.org/lkml/
reply other threads:[~2001-01-08 17:21 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20010108182106.A11978@gruyere.muc.suse.de \
--to=ak@suse.de \
--cc=alan@lxorguk.ukuu.org.uk \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).