Commit 5c8136fa authored Jan 23, 2018 by Christophe Leroy Committed by Michael Ellerman Jan 27, 2018

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 <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

parent fc5f6221

arch/powerpc/mm/tlb_nohash.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -388,6 +388,9 @@ void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
		unsigned long end)

		{
		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);