From: Guo Ren <ren_guo@xxxxxxxxx>
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_guo@xxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
---
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
