From 5c8136fa1af7c0e9b4aec89cf2832f6e5197ce32 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Tue, 23 Jan 2018 14:22:50 +0100 Subject: [PATCH] powerpc/mm/nohash: do not flush the entire mm when range is a single page Most of the time, flush_tlb_range() is called on single pages. At the time being, flush_tlb_range() inconditionnaly calls flush_tlb_mm() which flushes at least the entire PID pages and on older CPUs like 4xx or 8xx it flushes the entire TLB table. This patch calls flush_tlb_page() instead of flush_tlb_mm() when the range is a single page. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman --- arch/powerpc/mm/tlb_nohash.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/mm/tlb_nohash.c b/arch/powerpc/mm/tlb_nohash.c index bfc4a08..15fe5f0 100644 --- a/arch/powerpc/mm/tlb_nohash.c +++ b/arch/powerpc/mm/tlb_nohash.c @@ -388,7 +388,10 @@ void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end) { - flush_tlb_mm(vma->vm_mm); + if (end - start == PAGE_SIZE && !(start & ~PAGE_MASK)) + flush_tlb_page(vma, start); + else + flush_tlb_mm(vma->vm_mm); } EXPORT_SYMBOL(flush_tlb_range); -- 2.7.4