From: Guo Ren <ren_...@c-sky.com> We use defer cache flush mechanism to improve the performance of 610, but the implementation is wrong. We fix it up now and update the mechanism:
- Zero page needn't be flushed. - If page is file mapping & non-touched in user space, defer flush. - If page is anon mapping or dirty file mapping, flush immediately. - In update_mmu_cache finish the defer flush by flush_dcache_page(). For 610 we need take care the dcache aliasing issue: - VIPT cache with 8K-bytes size per way in 4K page granularity. Signed-off-by: Guo Ren <ren_...@c-sky.com> Cc: Arnd Bergmann <a...@arndb.de> --- arch/csky/abiv1/cacheflush.c | 50 +++++++++++++++++++----------------- arch/csky/abiv1/inc/abi/cacheflush.h | 4 +-- 2 files changed, 29 insertions(+), 25 deletions(-) diff --git a/arch/csky/abiv1/cacheflush.c b/arch/csky/abiv1/cacheflush.c index 10af8b6..fee99fc 100644 --- a/arch/csky/abiv1/cacheflush.c +++ b/arch/csky/abiv1/cacheflush.c @@ -11,42 +11,46 @@ #include <asm/cacheflush.h> #include <asm/cachectl.h> +#define PG_dcache_clean PG_arch_1 + void flush_dcache_page(struct page *page) { - struct address_space *mapping = page_mapping(page); - unsigned long addr; + struct address_space *mapping; - if (mapping && !mapping_mapped(mapping)) { - set_bit(PG_arch_1, &(page)->flags); + if (page == ZERO_PAGE(0)) return; - } - /* - * We could delay the flush for the !page_mapping case too. But that - * case is for exec env/arg pages and those are %99 certainly going to - * get faulted into the tlb (and thus flushed) anyways. - */ - addr = (unsigned long) page_address(page); - dcache_wb_range(addr, addr + PAGE_SIZE); + mapping = page_mapping_file(page); + + if (mapping && !page_mapcount(page)) + clear_bit(PG_dcache_clean, &page->flags); + else { + dcache_wbinv_all(); + if (mapping) + icache_inv_all(); + set_bit(PG_dcache_clean, &page->flags); + } } +EXPORT_SYMBOL(flush_dcache_page); -void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, - pte_t *pte) +void update_mmu_cache(struct vm_area_struct *vma, unsigned long addr, + pte_t *ptep) { - unsigned long addr; + unsigned long pfn = pte_pfn(*ptep); struct page *page; - unsigned long pfn; - pfn = pte_pfn(*pte); - if (unlikely(!pfn_valid(pfn))) + if (!pfn_valid(pfn)) return; page = pfn_to_page(pfn); - addr = (unsigned long) page_address(page); + if (page == ZERO_PAGE(0)) + return; - if (vma->vm_flags & VM_EXEC || - pages_do_alias(addr, address & PAGE_MASK)) - cache_wbinv_all(); + if (!test_and_set_bit(PG_dcache_clean, &page->flags)) + dcache_wbinv_all(); - clear_bit(PG_arch_1, &(page)->flags); + if (page_mapping_file(page)) { + if (vma->vm_flags & VM_EXEC) + icache_inv_all(); + } } diff --git a/arch/csky/abiv1/inc/abi/cacheflush.h b/arch/csky/abiv1/inc/abi/cacheflush.h index 5f663ae..fce5604 100644 --- a/arch/csky/abiv1/inc/abi/cacheflush.h +++ b/arch/csky/abiv1/inc/abi/cacheflush.h @@ -26,8 +26,8 @@ extern void flush_dcache_page(struct page *); #define flush_icache_page(vma, page) cache_wbinv_all() #define flush_icache_range(start, end) cache_wbinv_range(start, end) -#define flush_icache_user_range(vma, pg, adr, len) \ - cache_wbinv_range(adr, adr + len) +#define flush_icache_user_range(vma,page,addr,len) \ + flush_dcache_page(page) #define copy_from_user_page(vma, page, vaddr, dst, src, len) \ do { \ -- 2.7.4