Merge branch 'WIP.x86/asm' into x86/urgent, because the topic is ready

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 68 insertions, 0 deletions

diff --git a/arch/nds32/include/asm/mmu_context.h b/arch/nds32/include/asm/mmu_context.h
new file mode 100644
index 000000000000..fd7d13cefccc
--- /dev/null
+++ b/arch/nds32/include/asm/mmu_context.h
@@ -0,0 +1,68 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+
+#ifndef __ASM_NDS32_MMU_CONTEXT_H
+#define __ASM_NDS32_MMU_CONTEXT_H
+
+#include <linux/spinlock.h>
+#include <asm/tlbflush.h>
+#include <asm/proc-fns.h>
+#include <asm-generic/mm_hooks.h>
+
+static inline int
+init_new_context(struct task_struct *tsk, struct mm_struct *mm)
+{
+	mm->context.id = 0;
+	return 0;
+}
+
+#define destroy_context(mm)	do { } while(0)
+
+#define CID_BITS	9
+extern spinlock_t cid_lock;
+extern unsigned int cpu_last_cid;
+
+static inline void __new_context(struct mm_struct *mm)
+{
+	unsigned int cid;
+	unsigned long flags;
+
+	spin_lock_irqsave(&cid_lock, flags);
+	cid = cpu_last_cid;
+	cpu_last_cid += 1 << TLB_MISC_offCID;
+	if (cpu_last_cid == 0)
+		cpu_last_cid = 1 << TLB_MISC_offCID << CID_BITS;
+
+	if ((cid & TLB_MISC_mskCID) == 0)
+		flush_tlb_all();
+	spin_unlock_irqrestore(&cid_lock, flags);
+
+	mm->context.id = cid;
+}
+
+static inline void check_context(struct mm_struct *mm)
+{
+	if (unlikely
+	    ((mm->context.id ^ cpu_last_cid) >> TLB_MISC_offCID >> CID_BITS))
+		__new_context(mm);
+}
+
+static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
+{
+}
+
+static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
+			     struct task_struct *tsk)
+{
+	unsigned int cpu = smp_processor_id();
+
+	if (!cpumask_test_and_set_cpu(cpu, mm_cpumask(next)) || prev != next) {
+		check_context(next);
+		cpu_switch_mm(next);
+	}
+}
+
+#define deactivate_mm(tsk,mm)	do { } while (0)
+#define activate_mm(prev,next)	switch_mm(prev, next, NULL)
+
+#endif