Re: [RFC PATCH] ARM: Assume new page cache pages have dirty D-cache

Catalin Marinas
2010-03-04T17:28:11Z

On Thu, 2010-03-04 at 16:44 +0000, Russell King - ARM Linux wrote:
> On Tue, Mar 02, 2010 at 05:34:29PM +0000, Catalin Marinas wrote:
> > There are places in Linux where writes to newly allocated page cache
> > pages happen without a subsequent call to flush_dcache_page() (several
> > PIO drivers including USB HCD). This patch changes the meaning of
> > PG_arch_1 to be PG_dcache_clean and always flush the D-cache for a newly
> > mapped page in update_mmu_cache().
> >
> > The patch also sets the PG_arch_1 bit in the DMA cache maintenance
> > function to avoid additional cache flushing in update_mmu_cache().
> ...
> > arch/arm/include/asm/cacheflush.h | 6 +++---
> > arch/arm/mm/copypage-v6.c | 2 +-
> > arch/arm/mm/dma-mapping.c | 5 +++++
> > arch/arm/mm/fault-armv.c | 2 +-
> > arch/arm/mm/flush.c | 2 +-
> > 5 files changed, 11 insertions(+), 6 deletions(-)
>
> Could you please send for RFC a fuller patch which covers all places that
> PG_dcache_dirty is used and/or mentioned?

Ah, I thought the compilation would find them but I was wrong. I'll
repost.

--
Catalin