diff options
author | John David Anglin <dave.anglin@bell.net> | 2013-02-03 22:59:09 +0000 |
---|---|---|
committer | Helge Deller <deller@gmx.de> | 2013-02-20 22:49:19 +0100 |
commit | 7633453978c54874849c5f40487ac9e14d43fc12 (patch) | |
tree | 552bc9a01785d2bcdca5cb283b6b2b3af5e3e5b8 /arch/parisc/include | |
parent | 93c3e913e104c9277e32a0d7e03f268d146c57ee (diff) |
parisc: fixes and cleanups in page cache flushing (1/4)
This is the first patch in a series of 4, with which the page cache flushing of
parisc will gets fixed and enhanced. This even fixes the nasty "minifail" bug
(http://wiki.parisc-linux.org/TestCases?highlight=%28minifail%29) which
prevented parisc to stay an official debian port. Basically the flush in
copy_user_page together with the TLB patch from commit
7139bc1579901b53db7e898789e916ee2fb52d78 is what fixes the minifail bug.
This patch still uses the TMPALIAS approach. The new copy_user_page
implementation calls flush_dcache_page_asm to flush the user dcache page
(crucial for minifail fix) via a kernel TMPALIAS mapping. After that, it just
copies the page using the kernel mapping. It does a final flush if needed.
Generally it is hard to avoid doing some cache flushes using the kernel mapping
(e.g., copy_to_user_page and copy_from_user_page).
This patch depends on a subsequent change to pacache.S implementing
clear_page_asm and copy_page_asm. These are optimized routines to clear and
copy a page. The calls in clear_user_page and copy_user_page could be replaced
by calls to memset and memcpy, respectively. I tested prefetch optimizations
in clear_page_asm and copy_page_asm but didn't see any significant performance
improvement on rp3440. I'm not sure if these are routines are significantly
faster than memset and/or memcpy, but they are there for further performance
evaluation.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Diffstat (limited to 'arch/parisc/include')
-rw-r--r-- | arch/parisc/include/asm/page.h | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/arch/parisc/include/asm/page.h b/arch/parisc/include/asm/page.h index 4e0e7dbf0f3f..b7adb2ac049c 100644 --- a/arch/parisc/include/asm/page.h +++ b/arch/parisc/include/asm/page.h @@ -21,15 +21,27 @@ #include <asm/types.h> #include <asm/cache.h> -#define clear_page(page) memset((void *)(page), 0, PAGE_SIZE) -#define copy_page(to,from) copy_user_page_asm((void *)(to), (void *)(from)) +#define clear_page(page) clear_page_asm((void *)(page)) +#define copy_page(to, from) copy_page_asm((void *)(to), (void *)(from)) struct page; -void copy_user_page_asm(void *to, void *from); +void clear_page_asm(void *page); +void copy_page_asm(void *to, void *from); +void clear_user_page(void *vto, unsigned long vaddr, struct page *pg); void copy_user_page(void *vto, void *vfrom, unsigned long vaddr, struct page *pg); -void clear_user_page(void *page, unsigned long vaddr, struct page *pg); + +/* #define CONFIG_PARISC_TMPALIAS */ + +#ifdef CONFIG_PARISC_TMPALIAS +void clear_user_highpage(struct page *page, unsigned long vaddr); +#define clear_user_highpage clear_user_highpage +struct vm_area_struct; +void copy_user_highpage(struct page *to, struct page *from, + unsigned long vaddr, struct vm_area_struct *vma); +#define __HAVE_ARCH_COPY_USER_HIGHPAGE +#endif /* * These are used to make use of C type-checking.. |