From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: <linuxppc-dev@ozlabs.org>
Subject: [PATCH 8/14] powerpc: Fix kmalloc alignmenent on non-coherent DMA
Date: Wed, 21 Nov 2007 17:15:01 +1100 [thread overview]
Message-ID: <20071121061551.E97A1DDF08@ozlabs.org> (raw)
On platforms doing non-coherent DMA (4xx, 8xx, ...), it's important that
kmalloc minimum alignment is set to the cache line size, to avoid sharing
cache lines between different objects.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
include/asm-powerpc/page_32.h | 4 ++++
1 file changed, 4 insertions(+)
Index: linux-work/include/asm-powerpc/page_32.h
===================================================================
--- linux-work.orig/include/asm-powerpc/page_32.h 2007-11-19 15:01:08.000000000 +1100
+++ linux-work/include/asm-powerpc/page_32.h 2007-11-19 15:01:17.000000000 +1100
@@ -6,6 +6,10 @@
#define PPC_MEMSTART 0
+#ifdef CONFIG_NOT_COHERENT_CACHE
+#define ARCH_KMALLOC_MINALIGN L1_CACHE_BYTES
+#endif
+
#ifndef __ASSEMBLY__
/*
* The basic type of a PTE - 64 bits for those CPUs with > 32 bit
reply other threads:[~2007-11-21 6:15 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=20071121061551.E97A1DDF08@ozlabs.org \
--to=benh@kernel.crashing.org \
--cc=linuxppc-dev@ozlabs.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).