x86: bring tlb_32.c and _64.c into alignment

Bring arch/x86/kernel/tlb_32.c and _64.c closer into alignment, so that unification is more straightforward. After this patch, the remaining differences come down to UV support and the distinction between percpu and pda variables.

---

arch/x86/kernel/tlb_32.c |   39 +++++++++++++++++++--------------------
arch/x86/kernel/tlb_64.c |   12 +++++++-----
2 files changed, 26 insertions(+), 25 deletions(-)

===================================================================

@@ -1,7 +1,7 @@
-#include <linux/cpu.h>
+#include <linux/smp.h>

#include <linux/interrupt.h>
-#include <linux/smp.h>
#include <linux/percpu.h>
+#include <linux/module.h>

#include <asm/tlbflush.h>

@@ -46,25 +46,25 @@
* 1) switch_mm() either 1a) or 1b)
* 1a) thread switch to a different mm
* 1a1) cpu_clear(cpu, old_mm->cpu_vm_mask);
- * Stop ipi delivery for the old mm. This is not synchronized with
- * the other cpus, but smp_invalidate_interrupt ignore flush ipis
- * for the wrong mm, and in the worst case we perform a superfluous
- * tlb flush.
+ * Stop ipi delivery for the old mm. This is not synchronized with
+ * the other cpus, but tlb_invalidate() ignores flush ipis
+ * for the wrong mm, and in the worst case we perform a superfluous
+ * tlb flush.
* 1a2) set cpu_tlbstate to TLBSTATE_OK
* Now the smp_invalidate_interrupt won't call leave_mm if cpu0
* was in lazy tlb mode.
* 1a3) update cpu_tlbstate[].active_mm
- * Now cpu0 accepts tlb flushes for the new mm.
+ * Now cpu0 accepts tlb flushes for the new mm.
* 1a4) cpu_set(cpu, new_mm->cpu_vm_mask);
- * Now the other cpus will send tlb flush ipis.
+ * Now the other cpus will send tlb flush ipis.
* 1a4) change cr3.
* 1b) thread switch without mm change
* cpu_tlbstate[].active_mm is correct, cpu0 already handles
* flush ipis.
* 1b1) set cpu_tlbstate to TLBSTATE_OK
* 1b2) test_and_set the cpu bit in cpu_vm_mask.
- * Atomically set the bit [other cpus will start sending flush ipis],
- * and test the bit.
+ * Atomically set the bit [other cpus will start sending flush ipis],
+ * and test the bit.
* 1b3) if the bit was 0: leave_mm was called, flush the tlb.
* 2) switch %%esp, ie current
*
@@ -83,26 +83,27 @@
*
* 1) Flush the tlb entries if the cpu uses the mm that's being flushed.
* 2) Leave the mm if we are in the lazy tlb mode.
+ *
+ * Interrupts are disabled.
*/

static void tlb_invalidate(void *arg)
{
- struct tlb_flush *flush = arg;
- unsigned long cpu;
+ struct tlb_flush *f = arg;
+ int cpu;

- cpu = get_cpu();
+ cpu = smp_processor_id();

- if (flush->mm == per_cpu(cpu_tlbstate, cpu).active_mm) {

+	if (f->mm == per_cpu(cpu_tlbstate, cpu).active_mm) {
		if (per_cpu(cpu_tlbstate, cpu).state == TLBSTATE_OK) {
-			if (flush->va == TLB_FLUSH_ALL)
+			if (f->va == TLB_FLUSH_ALL)
				local_flush_tlb();
			else
-				__flush_tlb_one(flush->va);
+				__flush_tlb_one(f->va);
		} else
			leave_mm(cpu);
	}

-	put_cpu_no_resched();
	__get_cpu_var(irq_stat).irq_tlb_count++;
}

@@ -164,7 +165,7 @@

	if (current->active_mm == mm) {
		if (current->mm)
			__flush_tlb_one(va);
-		 else
+		else
			leave_mm(smp_processor_id());
	}

@@ -173,7 +174,6 @@

	preempt_enable();
}

-EXPORT_SYMBOL(flush_tlb_page);

static void do_flush_tlb_all(void *info)
{
@@ -188,4 +188,3 @@

{
	on_each_cpu(do_flush_tlb_all, NULL, 1);
}

-
===================================================================

@@ -1,10 +1,8 @@
-#include <linux/mm.h>

#include <linux/smp.h>
-#include <linux/kernel_stat.h>
+#include <linux/interrupt.h>
#include <linux/module.h>

#include <asm/tlbflush.h>
-#include <asm/mmu_context.h>

/* For UV tlb flush */
#include <asm/uv/uv_hub.h>
@@ -29,6 +27,9 @@
/*
* We cannot call mmdrop() because we are in interrupt context,
* instead update mm->cpu_vm_mask.
+ *
+ * We need to reload %cr3 since the page tables may be going
+ * away from under us..
*/
void leave_mm(int cpu)
{
@@ -47,7 +48,7 @@
* 1a) thread switch to a different mm
* 1a1) cpu_clear(cpu, old_mm->cpu_vm_mask);
* Stop ipi delivery for the old mm. This is not synchronized with
- * the other cpus, but smp_invalidate_interrupt ignore flush ipis
+ * the other cpus, but tlb_invalidate() ignores flush ipis
* for the wrong mm, and in the worst case we perform a superfluous
* tlb flush.
* 1a2) set cpu mmu_state to TLBSTATE_OK
@@ -103,6 +104,7 @@

		} else
			leave_mm(cpu);
	}
+
	add_pda(irq_tlb_count, 1);
}

@@ -111,7 +113,7 @@

{
	struct tlb_flush flush = {
		.mm = mm,
-		.va = va,
+		.va = va
	};

	if (is_uv_system() && uv_flush_tlb_others(cpumaskp, mm, va))