[SPARC64]: Fix memory leak when cpu hotplugging.

Every time a cpu is added via hotplug, we allocate the per-cpu MONDO
queues but we never free them up. Freeing isn't easy since the first
cpu gets this memory from bootmem.

Therefore, the simplest thing to do to fix this bug is to allocate the
queues for all possible cpus at boot time.

Signed-off-by: David S. Miller <[e-mail]>

arch/sparc64/kernel/hvtramp.S

···
 	call		hard_smp_processor_id
 	 nop
 
-	mov		%o0, %o1
-	mov		0, %o0
-	mov		0, %o2
-	call		sun4v_init_mondo_queues
-	 mov		1, %o3
+	call		sun4v_register_mondo_queues
+	 nop
 
 	call		init_cur_cpu_trap
 	 mov		%g6, %o0

arch/sparc64/kernel/irq.c

···
 	}
 }
 
-static void __cpuinit sun4v_register_mondo_queues(int this_cpu)
+void __cpuinit sun4v_register_mondo_queues(int this_cpu)
 {
 	struct trap_per_cpu *tb = &trap_block[this_cpu];
 
···
 			   tb->nonresum_qmask);
 }
 
-static void __cpuinit alloc_one_mondo(unsigned long *pa_ptr, unsigned long qmask, int use_bootmem)
+static void __init alloc_one_mondo(unsigned long *pa_ptr, unsigned long qmask)
 {
 	unsigned long size = PAGE_ALIGN(qmask + 1);
-	unsigned long order = get_order(size);
-	void *p = NULL;
-
-	if (use_bootmem) {
-		p = __alloc_bootmem_low(size, size, 0);
-	} else {
-		struct page *page = alloc_pages(GFP_ATOMIC | __GFP_ZERO, order);
-		if (page)
-			p = page_address(page);
-	}
-
+	void *p = __alloc_bootmem_low(size, size, 0);
 	if (!p) {
 		prom_printf("SUN4V: Error, cannot allocate mondo queue.\n");
 		prom_halt();
···
 	*pa_ptr = __pa(p);
 }
 
-static void __cpuinit alloc_one_kbuf(unsigned long *pa_ptr, unsigned long qmask, int use_bootmem)
+static void __init alloc_one_kbuf(unsigned long *pa_ptr, unsigned long qmask)
 {
 	unsigned long size = PAGE_ALIGN(qmask + 1);
-	unsigned long order = get_order(size);
-	void *p = NULL;
-
-	if (use_bootmem) {
-		p = __alloc_bootmem_low(size, size, 0);
-	} else {
-		struct page *page = alloc_pages(GFP_ATOMIC | __GFP_ZERO, order);
-		if (page)
-			p = page_address(page);
-	}
+	void *p = __alloc_bootmem_low(size, size, 0);
 
 	if (!p) {
 		prom_printf("SUN4V: Error, cannot allocate kbuf page.\n");
···
 	*pa_ptr = __pa(p);
 }
 
-static void __cpuinit init_cpu_send_mondo_info(struct trap_per_cpu *tb, int use_bootmem)
+static void __init init_cpu_send_mondo_info(struct trap_per_cpu *tb)
 {
 #ifdef CONFIG_SMP
 	void *page;
 
 	BUILD_BUG_ON((NR_CPUS * sizeof(u16)) > (PAGE_SIZE - 64));
 
-	if (use_bootmem)
-		page = alloc_bootmem_low_pages(PAGE_SIZE);
-	else
-		page = (void *) get_zeroed_page(GFP_ATOMIC);
-
+	page = alloc_bootmem_low_pages(PAGE_SIZE);
 	if (!page) {
 		prom_printf("SUN4V: Error, cannot allocate cpu mondo page.\n");
 		prom_halt();
···
 #endif
 }
 
-/* Allocate and register the mondo and error queues for this cpu.  */
-void __cpuinit sun4v_init_mondo_queues(int use_bootmem, int cpu, int alloc, int load)
+/* Allocate mondo and error queues for all possible cpus.  */
+static void __init sun4v_init_mondo_queues(void)
 {
-	struct trap_per_cpu *tb = &trap_block[cpu];
+	int cpu;
 
-	if (alloc) {
-		alloc_one_mondo(&tb->cpu_mondo_pa, tb->cpu_mondo_qmask, use_bootmem);
-		alloc_one_mondo(&tb->dev_mondo_pa, tb->dev_mondo_qmask, use_bootmem);
-		alloc_one_mondo(&tb->resum_mondo_pa, tb->resum_qmask, use_bootmem);
-		alloc_one_kbuf(&tb->resum_kernel_buf_pa, tb->resum_qmask, use_bootmem);
-		alloc_one_mondo(&tb->nonresum_mondo_pa, tb->nonresum_qmask, use_bootmem);
-		alloc_one_kbuf(&tb->nonresum_kernel_buf_pa, tb->nonresum_qmask, use_bootmem);
+	for_each_possible_cpu(cpu) {
+		struct trap_per_cpu *tb = &trap_block[cpu];
 
-		init_cpu_send_mondo_info(tb, use_bootmem);
+		alloc_one_mondo(&tb->cpu_mondo_pa, tb->cpu_mondo_qmask);
+		alloc_one_mondo(&tb->dev_mondo_pa, tb->dev_mondo_qmask);
+		alloc_one_mondo(&tb->resum_mondo_pa, tb->resum_qmask);
+		alloc_one_kbuf(&tb->resum_kernel_buf_pa, tb->resum_qmask);
+		alloc_one_mondo(&tb->nonresum_mondo_pa, tb->nonresum_qmask);
+		alloc_one_kbuf(&tb->nonresum_kernel_buf_pa,
+			       tb->nonresum_qmask);
+
+		init_cpu_send_mondo_info(tb);
 	}
 
-	if (load) {
-		if (cpu != hard_smp_processor_id()) {
-			prom_printf("SUN4V: init mondo on cpu %d not %d\n",
-				    cpu, hard_smp_processor_id());
-			prom_halt();
-		}
-		sun4v_register_mondo_queues(cpu);
-	}
+	/* Load up the boot cpu's entries.  */
+	sun4v_register_mondo_queues(hard_smp_processor_id());
 }
 
 static struct irqaction timer_irq_action = {
···
 	memset(&ivector_table[0], 0, sizeof(ivector_table));
 
 	if (tlb_type == hypervisor)
-		sun4v_init_mondo_queues(1, hard_smp_processor_id(), 1, 1);
+		sun4v_init_mondo_queues();
 
 	/* We need to clear any IRQ's pending in the soft interrupt
 	 * registers, a spurious one could be left around from the

arch/sparc64/kernel/smp.c

···
 }
 #endif
 
-extern void sun4v_init_mondo_queues(int use_bootmem, int cpu, int alloc, int load);
-
 extern unsigned long sparc64_cpu_startup;
 
 /* The OBP cpu startup callback truncates the 3rd arg cookie to
···
 	cpu_new_thread = task_thread_info(p);
 
 	if (tlb_type == hypervisor) {
-		/* Alloc the mondo queues, cpu will load them.  */
-		sun4v_init_mondo_queues(0, cpu, 1, 0);
-
 #if defined(CONFIG_SUN_LDOMS) && defined(CONFIG_HOTPLUG_CPU)
 		if (ldom_domaining_enabled)
 			ldom_startcpu_cpuid(cpu,

arch/sparc64/kernel/trampoline.S

···
 	call		hard_smp_processor_id
 	 nop
 	
-	mov		%o0, %o1
-	mov		0, %o0
-	mov		0, %o2
-	call		sun4v_init_mondo_queues
-	 mov		1, %o3
+	call		sun4v_register_mondo_queues
+	 nop
 
 1:	call		init_cur_cpu_trap
 	 ldx		[%l0], %o0