Commit 524e00b3 authored by Liam R. Howlett's avatar Liam R. Howlett Committed by Andrew Morton
Browse files

mm: remove rb tree. 

Remove the RB tree and start using the maple tree for vm_area_struct
tracking.

Drop validate_mm() calls in expand_upwards() and expand_downwards() as the
lock is not held.

Link: https://lkml.kernel.org/r/20220906194824.2110408-18-Liam.Howlett@oracle.com


Signed-off-by: default avatarLiam R. Howlett <Liam.Howlett@Oracle.com>
Tested-by: default avatarYu Zhao <yuzhao@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: SeongJae Park <sj@kernel.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 0c563f14

arch/x86/kernel/tboot.c

+0 −1
Original line number Diff line number Diff line
@@ -95,7 +95,6 @@ void __init tboot_probe(void) 


static pgd_t *tboot_pg_dir;

static struct mm_struct tboot_mm = {

	.mm_rb          = RB_ROOT,

	.mm_mt          = MTREE_INIT_EXT(mm_mt, MM_MT_FLAGS, tboot_mm.mmap_lock),

	.pgd            = swapper_pg_dir,

	.mm_users       = ATOMIC_INIT(2),

drivers/firmware/efi/efi.c

+0 −1
Original line number Diff line number Diff line
@@ -57,7 +57,6 @@ static unsigned long __initdata mem_reserve = EFI_INVALID_TABLE_ADDR; 
static unsigned long __initdata rt_prop = EFI_INVALID_TABLE_ADDR;



struct mm_struct efi_mm = {

	.mm_rb			= RB_ROOT,

	.mm_mt			= MTREE_INIT_EXT(mm_mt, MM_MT_FLAGS, efi_mm.mmap_lock),

	.mm_users		= ATOMIC_INIT(2),

	.mm_count		= ATOMIC_INIT(1),

include/linux/mm.h

+0 −2
Original line number Diff line number Diff line
@@ -2654,8 +2654,6 @@ extern int __split_vma(struct mm_struct *, struct vm_area_struct *, 
extern int split_vma(struct mm_struct *, struct vm_area_struct *,

	unsigned long addr, int new_below);

extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *);

extern void __vma_link_rb(struct mm_struct *, struct vm_area_struct *,

	struct rb_node **, struct rb_node *);

extern void unlink_file_vma(struct vm_area_struct *);

extern struct vm_area_struct *copy_vma(struct vm_area_struct **,

	unsigned long addr, unsigned long len, pgoff_t pgoff,

include/linux/mm_types.h

+0 −14
Original line number Diff line number Diff line
@@ -410,19 +410,6 @@ struct vm_area_struct { 


	/* linked list of VM areas per task, sorted by address */

	struct vm_area_struct *vm_next, *vm_prev;



	struct rb_node vm_rb;



	/*

	 * Largest free memory gap in bytes to the left of this VMA.

	 * Either between this VMA and vma->vm_prev, or between one of the

	 * VMAs below us in the VMA rbtree and its ->vm_prev. This helps

	 * get_unmapped_area find a free area of the right size.

	 */

	unsigned long rb_subtree_gap;



	/* Second cache line starts here. */



	struct mm_struct *vm_mm;	/* The address space we belong to. */



	/*
@@ -488,7 +475,6 @@ struct mm_struct { 
	struct {

		struct vm_area_struct *mmap;		/* list of VMAs */

		struct maple_tree mm_mt;

		struct rb_root mm_rb;

		u64 vmacache_seqnum;                   /* per-thread vmacache */

#ifdef CONFIG_MMU

		unsigned long (*get_unmapped_area) (struct file *filp,

kernel/fork.c

+0 −8
Original line number Diff line number Diff line
@@ -581,7 +581,6 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, 
					struct mm_struct *oldmm)

{

	struct vm_area_struct *mpnt, *tmp, *prev, **pprev;

	struct rb_node **rb_link, *rb_parent;

	int retval;

	unsigned long charge = 0;

	LIST_HEAD(uf);
@@ -608,8 +607,6 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, 
	mm->exec_vm = oldmm->exec_vm;

	mm->stack_vm = oldmm->stack_vm;



	rb_link = &mm->mm_rb.rb_node;

	rb_parent = NULL;

	pprev = &mm->mmap;

	retval = ksm_fork(mm, oldmm);

	if (retval)
@@ -701,10 +698,6 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, 
		tmp->vm_prev = prev;

		prev = tmp;



		__vma_link_rb(mm, tmp, rb_link, rb_parent);

		rb_link = &tmp->vm_rb.rb_right;

		rb_parent = &tmp->vm_rb;



		/* Link the vma into the MT */

		mas.index = tmp->vm_start;

		mas.last = tmp->vm_end - 1;
@@ -1133,7 +1126,6 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p, 
	struct user_namespace *user_ns)

{

	mm->mmap = NULL;

	mm->mm_rb = RB_ROOT;

	mt_init_flags(&mm->mm_mt, MM_MT_FLAGS);

	mt_set_external_lock(&mm->mm_mt, &mm->mmap_lock);

	mm->vmacache_seqnum = 0;