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-rw-r--r--arch/arm/mm/context.c17
1 files changed, 14 insertions, 3 deletions
diff --git a/arch/arm/mm/context.c b/arch/arm/mm/context.c
index 9da43a0fdcdf..fc84fcc74380 100644
--- a/arch/arm/mm/context.c
+++ b/arch/arm/mm/context.c
@@ -14,7 +14,8 @@
14#include <asm/mmu_context.h> 14#include <asm/mmu_context.h>
15#include <asm/tlbflush.h> 15#include <asm/tlbflush.h>
16 16
17unsigned int cpu_last_asid = { 1 << ASID_BITS }; 17static DEFINE_SPINLOCK(cpu_asid_lock);
18unsigned int cpu_last_asid = ASID_FIRST_VERSION;
18 19
19/* 20/*
20 * We fork()ed a process, and we need a new context for the child 21 * We fork()ed a process, and we need a new context for the child
@@ -31,15 +32,16 @@ void __new_context(struct mm_struct *mm)
31{ 32{
32 unsigned int asid; 33 unsigned int asid;
33 34
35 spin_lock(&cpu_asid_lock);
34 asid = ++cpu_last_asid; 36 asid = ++cpu_last_asid;
35 if (asid == 0) 37 if (asid == 0)
36 asid = cpu_last_asid = 1 << ASID_BITS; 38 asid = cpu_last_asid = ASID_FIRST_VERSION;
37 39
38 /* 40 /*
39 * If we've used up all our ASIDs, we need 41 * If we've used up all our ASIDs, we need
40 * to start a new version and flush the TLB. 42 * to start a new version and flush the TLB.
41 */ 43 */
42 if ((asid & ~ASID_MASK) == 0) { 44 if (unlikely((asid & ~ASID_MASK) == 0)) {
43 asid = ++cpu_last_asid; 45 asid = ++cpu_last_asid;
44 /* set the reserved ASID before flushing the TLB */ 46 /* set the reserved ASID before flushing the TLB */
45 asm("mcr p15, 0, %0, c13, c0, 1 @ set reserved context ID\n" 47 asm("mcr p15, 0, %0, c13, c0, 1 @ set reserved context ID\n"
@@ -47,7 +49,16 @@ void __new_context(struct mm_struct *mm)
47 : "r" (0)); 49 : "r" (0));
48 isb(); 50 isb();
49 flush_tlb_all(); 51 flush_tlb_all();
52 if (icache_is_vivt_asid_tagged()) {
53 asm("mcr p15, 0, %0, c7, c5, 0 @ invalidate I-cache\n"
54 "mcr p15, 0, %0, c7, c5, 6 @ flush BTAC/BTB\n"
55 :
56 : "r" (0));
57 dsb();
58 }
50 } 59 }
60 spin_unlock(&cpu_asid_lock);
51 61
62 mm->cpu_vm_mask = cpumask_of_cpu(smp_processor_id());
52 mm->context.id = asid; 63 mm->context.id = asid;
53} 64}