Commit 1c6b2ca5 authored Nov 19, 2007 by Paul Mundt

sh: Kill off UTLB flush in fast-path.



The __do_page_fault() fast-path contains a UTLB flush in order to
force an ITLB reload, this isn't needed in practice as the ITLB is
auto-reloaded from the UTLB anyways, which is already displaced by
the manual 'ldtlb' in the update_mmu_cache() path.

This provides a measurable speed up in the TLB miss fast-path.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

parent 03493374

arch/sh/mm/fault.c

+0 −8

Original line number	Diff line number	Diff line
		@@ -304,14 +304,6 @@ asmlinkage int __kprobes __do_page_fault(struct pt_regs *regs,
		entry = pte_mkdirty(entry);
		entry = pte_mkyoung(entry);

		#ifdef CONFIG_CPU_SH4
		/*
		* ITLB is not affected by "ldtlb" instruction.
		* So, we need to flush the entry by ourselves.
		*/
		local_flush_tlb_one(get_asid(), address & PAGE_MASK);
		#endif

		set_pte(pte, entry);
		update_mmu_cache(NULL, address, entry);
		ret = 0;