Revert "MIPS: Remove race window in page fault handling"
Revert commit 2a4a8b1e5d9d ("MIPS: Remove race window in page fault
handling") because it increased the number of flushed dcache pages and
became a performance problem for some workloads.
Signed-off-by: Lars Persson <larper@axis.com>
Cc: linux-mips@linux-mips.org
Cc: paul.burton@imgtec.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9345/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/mm/cache.c b/arch/mips/mm/cache.c
index 7e3ea77..f7b91d3 100644
--- a/arch/mips/mm/cache.c
+++ b/arch/mips/mm/cache.c
@@ -119,36 +119,25 @@
EXPORT_SYMBOL(__flush_anon_page);
-static void mips_flush_dcache_from_pte(pte_t pteval, unsigned long address)
+void __update_cache(struct vm_area_struct *vma, unsigned long address,
+ pte_t pte)
{
struct page *page;
- unsigned long pfn = pte_pfn(pteval);
+ unsigned long pfn, addr;
+ int exec = (vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc;
+ pfn = pte_pfn(pte);
if (unlikely(!pfn_valid(pfn)))
return;
-
page = pfn_to_page(pfn);
if (page_mapping(page) && Page_dcache_dirty(page)) {
- unsigned long page_addr = (unsigned long) page_address(page);
-
- if (!cpu_has_ic_fills_f_dc ||
- pages_do_alias(page_addr, address & PAGE_MASK))
- flush_data_cache_page(page_addr);
+ addr = (unsigned long) page_address(page);
+ if (exec || pages_do_alias(addr, address & PAGE_MASK))
+ flush_data_cache_page(addr);
ClearPageDcacheDirty(page);
}
}
-void set_pte_at(struct mm_struct *mm, unsigned long addr,
- pte_t *ptep, pte_t pteval)
-{
- if (cpu_has_dc_aliases || !cpu_has_ic_fills_f_dc) {
- if (pte_present(pteval))
- mips_flush_dcache_from_pte(pteval, addr);
- }
-
- set_pte(ptep, pteval);
-}
-
unsigned long _page_cachable_default;
EXPORT_SYMBOL(_page_cachable_default);