mm, vmalloc: remove list management of vmlist after initializing vmalloc (4341fa45) · Commits · 戴 / test

mm/vmalloc.c

+12 −40

Original line number	Diff line number	Diff line
		@@ -273,10 +273,6 @@ static unsigned long cached_align;

		static unsigned long vmap_area_pcpu_hole;

		/* Old vmalloc interfaces */
		static DEFINE_RWLOCK(vmlist_lock);
		static struct vm_struct *vmlist;

		static struct vmap_area *__find_vmap_area(unsigned long addr)
		{
		struct rb_node *n = vmap_area_root.rb_node;
		@@ -318,7 +314,7 @@ static void __insert_vmap_area(struct vmap_area *va)
		rb_link_node(&va->rb_node, parent, p);
		rb_insert_color(&va->rb_node, &vmap_area_root);

		/* address-sort this list so it is usable like the vmlist */
		/* address-sort this list */
		tmp = rb_prev(&va->rb_node);
		if (tmp) {
		struct vmap_area *prev;
		@@ -1130,6 +1126,7 @@ void vm_map_ram(struct page *pages, unsigned int count, int node, pgprot_t pro
		}
		EXPORT_SYMBOL(vm_map_ram);

		static struct vm_struct *vmlist __initdata;
		/**
		* vm_area_add_early - add vmap area early during boot
		* @vm: vm_struct to add
		@@ -1301,10 +1298,8 @@ static void setup_vmalloc_vm(struct vm_struct vm, struct vmap_area va,
		spin_unlock(&vmap_area_lock);
		}

		static void insert_vmalloc_vmlist(struct vm_struct *vm)
		static void clear_vm_unlist(struct vm_struct *vm)
		{
		struct vm_struct tmp, *p;

		/*
		* Before removing VM_UNLIST,
		* we should make sure that vm has proper values.
		@@ -1312,22 +1307,13 @@ static void insert_vmalloc_vmlist(struct vm_struct *vm)
		*/
		smp_wmb();
		vm->flags &= ~VM_UNLIST;

		write_lock(&vmlist_lock);
		for (p = &vmlist; (tmp = *p) != NULL; p = &tmp->next) {
		if (tmp->addr >= vm->addr)
		break;
		}
		vm->next = *p;
		*p = vm;
		write_unlock(&vmlist_lock);
		}

		static void insert_vmalloc_vm(struct vm_struct vm, struct vmap_area va,
		unsigned long flags, const void *caller)
		{
		setup_vmalloc_vm(vm, va, flags, caller);
		insert_vmalloc_vmlist(vm);
		clear_vm_unlist(vm);
		}

		static struct vm_struct *__get_vm_area_node(unsigned long size,
		@@ -1370,10 +1356,9 @@ static struct vm_struct *__get_vm_area_node(unsigned long size,

		/*
		* When this function is called from __vmalloc_node_range,
		* we do not add vm_struct to vmlist here to avoid
		* accessing uninitialized members of vm_struct such as
		* pages and nr_pages fields. They will be set later.
		* To distinguish it from others, we use a VM_UNLIST flag.
		* we add VM_UNLIST flag to avoid accessing uninitialized
		* members of vm_struct such as pages and nr_pages fields.
		* They will be set later.
		*/
		if (flags & VM_UNLIST)
		setup_vmalloc_vm(area, va, flags, caller);
		@@ -1462,20 +1447,6 @@ struct vm_struct remove_vm_area(const void addr)
		va->flags &= ~VM_VM_AREA;
		spin_unlock(&vmap_area_lock);

		if (!(vm->flags & VM_UNLIST)) {
		struct vm_struct tmp, *p;
		/*
		* remove from list and disallow access to
		* this vm_struct before unmap. (address range
		* confliction is maintained by vmap.)
		*/
		write_lock(&vmlist_lock);
		for (p = &vmlist; (tmp = *p) != vm; p = &tmp->next)
		;
		*p = tmp->next;
		write_unlock(&vmlist_lock);
		}

		vmap_debug_free_range(va->va_start, va->va_end);
		free_unmap_vmap_area(va);
		vm->size -= PAGE_SIZE;
		@@ -1695,10 +1666,11 @@ void *__vmalloc_node_range(unsigned long size, unsigned long align,
		return NULL;

		/*
		* In this function, newly allocated vm_struct is not added
		* to vmlist at __get_vm_area_node(). so, it is added here.
		* In this function, newly allocated vm_struct has VM_UNLIST flag.
		* It means that vm_struct is not fully initialized.
		* Now, it is fully initialized, so remove this flag here.
		*/
		insert_vmalloc_vmlist(area);
		clear_vm_unlist(area);

		/*
		* A ref_count = 3 is needed because the vm_struct and vmap_area
		@@ -2594,7 +2566,7 @@ static void show_numa_info(struct seq_file m, struct vm_struct v)
		if (!counters)
		return;

		/* Pair with smp_wmb() in insert_vmalloc_vmlist() */
		/* Pair with smp_wmb() in clear_vm_unlist() */
		smp_rmb();
		if (v->flags & VM_UNLIST)
		return;

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