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Diffstat (limited to 'arch/arm/mm/context.c')
-rw-r--r--arch/arm/mm/context.c32
1 files changed, 20 insertions, 12 deletions
diff --git a/arch/arm/mm/context.c b/arch/arm/mm/context.c
index 7a0511191f6b..2ac37372ef52 100644
--- a/arch/arm/mm/context.c
+++ b/arch/arm/mm/context.c
@@ -48,7 +48,7 @@ static DEFINE_RAW_SPINLOCK(cpu_asid_lock);
static atomic64_t asid_generation = ATOMIC64_INIT(ASID_FIRST_VERSION);
static DECLARE_BITMAP(asid_map, NUM_USER_ASIDS);
-static DEFINE_PER_CPU(atomic64_t, active_asids);
+DEFINE_PER_CPU(atomic64_t, active_asids);
static DEFINE_PER_CPU(u64, reserved_asids);
static cpumask_t tlb_flush_pending;
@@ -152,9 +152,9 @@ static int is_reserved_asid(u64 asid)
return 0;
}
-static void new_context(struct mm_struct *mm, unsigned int cpu)
+static u64 new_context(struct mm_struct *mm, unsigned int cpu)
{
- u64 asid = mm->context.id;
+ u64 asid = atomic64_read(&mm->context.id);
u64 generation = atomic64_read(&asid_generation);
if (asid != 0 && is_reserved_asid(asid)) {
@@ -181,13 +181,14 @@ static void new_context(struct mm_struct *mm, unsigned int cpu)
cpumask_clear(mm_cpumask(mm));
}
- mm->context.id = asid;
+ return asid;
}
void check_and_switch_context(struct mm_struct *mm, struct task_struct *tsk)
{
unsigned long flags;
unsigned int cpu = smp_processor_id();
+ u64 asid;
if (unlikely(mm->context.vmalloc_seq != init_mm.context.vmalloc_seq))
__check_vmalloc_seq(mm);
@@ -198,20 +199,27 @@ void check_and_switch_context(struct mm_struct *mm, struct task_struct *tsk)
*/
cpu_set_reserved_ttbr0();
- if (!((mm->context.id ^ atomic64_read(&asid_generation)) >> ASID_BITS)
- && atomic64_xchg(&per_cpu(active_asids, cpu), mm->context.id))
+ asid = atomic64_read(&mm->context.id);
+ if (!((asid ^ atomic64_read(&asid_generation)) >> ASID_BITS)
+ && atomic64_xchg(&per_cpu(active_asids, cpu), asid))
goto switch_mm_fastpath;
raw_spin_lock_irqsave(&cpu_asid_lock, flags);
/* Check that our ASID belongs to the current generation. */
- if ((mm->context.id ^ atomic64_read(&asid_generation)) >> ASID_BITS)
- new_context(mm, cpu);
-
- atomic64_set(&per_cpu(active_asids, cpu), mm->context.id);
- cpumask_set_cpu(cpu, mm_cpumask(mm));
+ asid = atomic64_read(&mm->context.id);
+ if ((asid ^ atomic64_read(&asid_generation)) >> ASID_BITS) {
+ asid = new_context(mm, cpu);
+ atomic64_set(&mm->context.id, asid);
+ }
- if (cpumask_test_and_clear_cpu(cpu, &tlb_flush_pending))
+ if (cpumask_test_and_clear_cpu(cpu, &tlb_flush_pending)) {
+ local_flush_bp_all();
local_flush_tlb_all();
+ dummy_flush_tlb_a15_erratum();
+ }
+
+ atomic64_set(&per_cpu(active_asids, cpu), asid);
+ cpumask_set_cpu(cpu, mm_cpumask(mm));
raw_spin_unlock_irqrestore(&cpu_asid_lock, flags);
switch_mm_fastpath: