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-rw-r--r--arch/x86/kernel/tlb_32.c256
1 files changed, 0 insertions, 256 deletions
diff --git a/arch/x86/kernel/tlb_32.c b/arch/x86/kernel/tlb_32.c
deleted file mode 100644
index ce505464224..00000000000
--- a/arch/x86/kernel/tlb_32.c
+++ /dev/null
@@ -1,256 +0,0 @@
1#include <linux/spinlock.h>
2#include <linux/cpu.h>
3#include <linux/interrupt.h>
4
5#include <asm/tlbflush.h>
6
7DEFINE_PER_CPU(struct tlb_state, cpu_tlbstate)
8 ____cacheline_aligned = { &init_mm, 0, };
9
10/* must come after the send_IPI functions above for inlining */
11#include <mach_ipi.h>
12
13/*
14 * Smarter SMP flushing macros.
15 * c/o Linus Torvalds.
16 *
17 * These mean you can really definitely utterly forget about
18 * writing to user space from interrupts. (Its not allowed anyway).
19 *
20 * Optimizations Manfred Spraul <manfred@colorfullife.com>
21 */
22
23static cpumask_t flush_cpumask;
24static struct mm_struct *flush_mm;
25static unsigned long flush_va;
26static DEFINE_SPINLOCK(tlbstate_lock);
27
28/*
29 * We cannot call mmdrop() because we are in interrupt context,
30 * instead update mm->cpu_vm_mask.
31 *
32 * We need to reload %cr3 since the page tables may be going
33 * away from under us..
34 */
35void leave_mm(int cpu)
36{
37 BUG_ON(x86_read_percpu(cpu_tlbstate.state) == TLBSTATE_OK);
38 cpu_clear(cpu, x86_read_percpu(cpu_tlbstate.active_mm)->cpu_vm_mask);
39 load_cr3(swapper_pg_dir);
40}
41EXPORT_SYMBOL_GPL(leave_mm);
42
43/*
44 *
45 * The flush IPI assumes that a thread switch happens in this order:
46 * [cpu0: the cpu that switches]
47 * 1) switch_mm() either 1a) or 1b)
48 * 1a) thread switch to a different mm
49 * 1a1) cpu_clear(cpu, old_mm->cpu_vm_mask);
50 * Stop ipi delivery for the old mm. This is not synchronized with
51 * the other cpus, but smp_invalidate_interrupt ignore flush ipis
52 * for the wrong mm, and in the worst case we perform a superfluous
53 * tlb flush.
54 * 1a2) set cpu_tlbstate to TLBSTATE_OK
55 * Now the smp_invalidate_interrupt won't call leave_mm if cpu0
56 * was in lazy tlb mode.
57 * 1a3) update cpu_tlbstate[].active_mm
58 * Now cpu0 accepts tlb flushes for the new mm.
59 * 1a4) cpu_set(cpu, new_mm->cpu_vm_mask);
60 * Now the other cpus will send tlb flush ipis.
61 * 1a4) change cr3.
62 * 1b) thread switch without mm change
63 * cpu_tlbstate[].active_mm is correct, cpu0 already handles
64 * flush ipis.
65 * 1b1) set cpu_tlbstate to TLBSTATE_OK
66 * 1b2) test_and_set the cpu bit in cpu_vm_mask.
67 * Atomically set the bit [other cpus will start sending flush ipis],
68 * and test the bit.
69 * 1b3) if the bit was 0: leave_mm was called, flush the tlb.
70 * 2) switch %%esp, ie current
71 *
72 * The interrupt must handle 2 special cases:
73 * - cr3 is changed before %%esp, ie. it cannot use current->{active_,}mm.
74 * - the cpu performs speculative tlb reads, i.e. even if the cpu only
75 * runs in kernel space, the cpu could load tlb entries for user space
76 * pages.
77 *
78 * The good news is that cpu_tlbstate is local to each cpu, no
79 * write/read ordering problems.
80 */
81
82/*
83 * TLB flush IPI:
84 *
85 * 1) Flush the tlb entries if the cpu uses the mm that's being flushed.
86 * 2) Leave the mm if we are in the lazy tlb mode.
87 */
88
89void smp_invalidate_interrupt(struct pt_regs *regs)
90{
91 unsigned long cpu;
92
93 cpu = get_cpu();
94
95 if (!cpu_isset(cpu, flush_cpumask))
96 goto out;
97 /*
98 * This was a BUG() but until someone can quote me the
99 * line from the intel manual that guarantees an IPI to
100 * multiple CPUs is retried _only_ on the erroring CPUs
101 * its staying as a return
102 *
103 * BUG();
104 */
105
106 if (flush_mm == x86_read_percpu(cpu_tlbstate.active_mm)) {
107 if (x86_read_percpu(cpu_tlbstate.state) == TLBSTATE_OK) {
108 if (flush_va == TLB_FLUSH_ALL)
109 local_flush_tlb();
110 else
111 __flush_tlb_one(flush_va);
112 } else
113 leave_mm(cpu);
114 }
115 ack_APIC_irq();
116 smp_mb__before_clear_bit();
117 cpu_clear(cpu, flush_cpumask);
118 smp_mb__after_clear_bit();
119out:
120 put_cpu_no_resched();
121 inc_irq_stat(irq_tlb_count);
122}
123
124void native_flush_tlb_others(const cpumask_t *cpumaskp, struct mm_struct *mm,
125 unsigned long va)
126{
127 cpumask_t cpumask = *cpumaskp;
128
129 /*
130 * A couple of (to be removed) sanity checks:
131 *
132 * - current CPU must not be in mask
133 * - mask must exist :)
134 */
135 BUG_ON(cpus_empty(cpumask));
136 BUG_ON(cpu_isset(smp_processor_id(), cpumask));
137 BUG_ON(!mm);
138
139#ifdef CONFIG_HOTPLUG_CPU
140 /* If a CPU which we ran on has gone down, OK. */
141 cpus_and(cpumask, cpumask, cpu_online_map);
142 if (unlikely(cpus_empty(cpumask)))
143 return;
144#endif
145
146 /*
147 * i'm not happy about this global shared spinlock in the
148 * MM hot path, but we'll see how contended it is.
149 * AK: x86-64 has a faster method that could be ported.
150 */
151 spin_lock(&tlbstate_lock);
152
153 flush_mm = mm;
154 flush_va = va;
155 cpus_or(flush_cpumask, cpumask, flush_cpumask);
156
157 /*
158 * Make the above memory operations globally visible before
159 * sending the IPI.
160 */
161 smp_mb();
162 /*
163 * We have to send the IPI only to
164 * CPUs affected.
165 */
166 send_IPI_mask(&cpumask, INVALIDATE_TLB_VECTOR);
167
168 while (!cpus_empty(flush_cpumask))
169 /* nothing. lockup detection does not belong here */
170 cpu_relax();
171
172 flush_mm = NULL;
173 flush_va = 0;
174 spin_unlock(&tlbstate_lock);
175}
176
177void flush_tlb_current_task(void)
178{
179 struct mm_struct *mm = current->mm;
180 cpumask_t cpu_mask;
181
182 preempt_disable();
183 cpu_mask = mm->cpu_vm_mask;
184 cpu_clear(smp_processor_id(), cpu_mask);
185
186 local_flush_tlb();
187 if (!cpus_empty(cpu_mask))
188 flush_tlb_others(cpu_mask, mm, TLB_FLUSH_ALL);
189 preempt_enable();
190}
191
192void flush_tlb_mm(struct mm_struct *mm)
193{
194 cpumask_t cpu_mask;
195
196 preempt_disable();
197 cpu_mask = mm->cpu_vm_mask;
198 cpu_clear(smp_processor_id(), cpu_mask);
199
200 if (current->active_mm == mm) {
201 if (current->mm)
202 local_flush_tlb();
203 else
204 leave_mm(smp_processor_id());
205 }
206 if (!cpus_empty(cpu_mask))
207 flush_tlb_others(cpu_mask, mm, TLB_FLUSH_ALL);
208
209 preempt_enable();
210}
211
212void flush_tlb_page(struct vm_area_struct *vma, unsigned long va)
213{
214 struct mm_struct *mm = vma->vm_mm;
215 cpumask_t cpu_mask;
216
217 preempt_disable();
218 cpu_mask = mm->cpu_vm_mask;
219 cpu_clear(smp_processor_id(), cpu_mask);
220
221 if (current->active_mm == mm) {
222 if (current->mm)
223 __flush_tlb_one(va);
224 else
225 leave_mm(smp_processor_id());
226 }
227
228 if (!cpus_empty(cpu_mask))
229 flush_tlb_others(cpu_mask, mm, va);
230
231 preempt_enable();
232}
233EXPORT_SYMBOL(flush_tlb_page);
234
235static void do_flush_tlb_all(void *info)
236{
237 unsigned long cpu = smp_processor_id();
238
239 __flush_tlb_all();
240 if (x86_read_percpu(cpu_tlbstate.state) == TLBSTATE_LAZY)
241 leave_mm(cpu);
242}
243
244void flush_tlb_all(void)
245{
246 on_each_cpu(do_flush_tlb_all, NULL, 1);
247}
248
249void reset_lazy_tlbstate(void)
250{
251 int cpu = raw_smp_processor_id();
252
253 per_cpu(cpu_tlbstate, cpu).state = 0;
254 per_cpu(cpu_tlbstate, cpu).active_mm = &init_mm;
255}
256
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