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howlettakpm00
howlett
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akpm00
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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: Liam R. Howlett <Liam.Howlett@Oracle.com> Tested-by: Yu 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: Andrew Morton <akpm@linux-foundation.org>
1 parent 0c563f1 commit 524e00b

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9 files changed

+144
-487
lines changed

9 files changed

+144
-487
lines changed

‎arch/x86/kernel/tboot.c‎

Lines changed: 0 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -95,7 +95,6 @@ void __init tboot_probe(void)
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9696
static pgd_t *tboot_pg_dir;
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static struct mm_struct tboot_mm = {
98-
.mm_rb = RB_ROOT,
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.mm_mt = MTREE_INIT_EXT(mm_mt, MM_MT_FLAGS, tboot_mm.mmap_lock),
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.pgd = swapper_pg_dir,
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.mm_users = ATOMIC_INIT(2),

‎drivers/firmware/efi/efi.c‎

Lines changed: 0 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -57,7 +57,6 @@ static unsigned long __initdata mem_reserve = EFI_INVALID_TABLE_ADDR;
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static unsigned long __initdata rt_prop = EFI_INVALID_TABLE_ADDR;
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5959
struct mm_struct efi_mm = {
60-
.mm_rb = RB_ROOT,
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.mm_mt = MTREE_INIT_EXT(mm_mt, MM_MT_FLAGS, efi_mm.mmap_lock),
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.mm_users = ATOMIC_INIT(2),
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.mm_count = ATOMIC_INIT(1),

‎include/linux/mm.h‎

Lines changed: 0 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -2654,8 +2654,6 @@ extern int __split_vma(struct mm_struct *, struct vm_area_struct *,
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extern int split_vma(struct mm_struct *, struct vm_area_struct *,
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unsigned long addr, int new_below);
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extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *);
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extern void __vma_link_rb(struct mm_struct *, struct vm_area_struct *,
2658-
struct rb_node **, struct rb_node *);
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extern void unlink_file_vma(struct vm_area_struct *);
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extern struct vm_area_struct *copy_vma(struct vm_area_struct **,
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unsigned long addr, unsigned long len, pgoff_t pgoff,

‎include/linux/mm_types.h‎

Lines changed: 0 additions & 14 deletions
Original file line numberDiff line numberDiff line change
@@ -410,19 +410,6 @@ struct vm_area_struct {
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411411
/* linked list of VM areas per task, sorted by address */
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struct vm_area_struct *vm_next, *vm_prev;
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struct rb_node vm_rb;
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/*
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* Largest free memory gap in bytes to the left of this VMA.
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* Either between this VMA and vma->vm_prev, or between one of the
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* VMAs below us in the VMA rbtree and its ->vm_prev. This helps
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* get_unmapped_area find a free area of the right size.
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*/
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unsigned long rb_subtree_gap;
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/* Second cache line starts here. */
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struct mm_struct *vm_mm; /* The address space we belong to. */
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428415
/*
@@ -488,7 +475,6 @@ struct mm_struct {
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struct {
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struct vm_area_struct *mmap; /* list of VMAs */
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struct maple_tree mm_mt;
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struct rb_root mm_rb;
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u64 vmacache_seqnum; /* per-thread vmacache */
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#ifdef CONFIG_MMU
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unsigned long (*get_unmapped_area) (struct file *filp,

‎kernel/fork.c‎

Lines changed: 0 additions & 8 deletions
Original file line numberDiff line numberDiff line change
@@ -581,7 +581,6 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
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struct mm_struct *oldmm)
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{
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struct vm_area_struct *mpnt, *tmp, *prev, **pprev;
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struct rb_node **rb_link, *rb_parent;
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int retval;
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unsigned long charge = 0;
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LIST_HEAD(uf);
@@ -608,8 +607,6 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
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mm->exec_vm = oldmm->exec_vm;
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mm->stack_vm = oldmm->stack_vm;
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rb_link = &mm->mm_rb.rb_node;
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rb_parent = NULL;
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pprev = &mm->mmap;
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retval = ksm_fork(mm, oldmm);
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if (retval)
@@ -701,10 +698,6 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
701698
tmp->vm_prev = prev;
702699
prev = tmp;
703700

704-
__vma_link_rb(mm, tmp, rb_link, rb_parent);
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rb_link = &tmp->vm_rb.rb_right;
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rb_parent = &tmp->vm_rb;
707-
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/* Link the vma into the MT */
709702
mas.index = tmp->vm_start;
710703
mas.last = tmp->vm_end - 1;
@@ -1133,7 +1126,6 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p,
11331126
struct user_namespace *user_ns)
11341127
{
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mm->mmap = NULL;
1136-
mm->mm_rb = RB_ROOT;
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mt_init_flags(&mm->mm_mt, MM_MT_FLAGS);
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mt_set_external_lock(&mm->mm_mt, &mm->mmap_lock);
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mm->vmacache_seqnum = 0;

‎mm/init-mm.c‎

Lines changed: 0 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -1,6 +1,5 @@
11
// SPDX-License-Identifier: GPL-2.0
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#include <linux/mm_types.h>
3-
#include <linux/rbtree.h>
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#include <linux/maple_tree.h>
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#include <linux/rwsem.h>
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#include <linux/spinlock.h>
@@ -29,7 +28,6 @@
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* and size this cpu_bitmask to NR_CPUS.
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*/
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struct mm_struct init_mm = {
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.mm_rb = RB_ROOT,
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.mm_mt = MTREE_INIT_EXT(mm_mt, MM_MT_FLAGS, init_mm.mmap_lock),
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.pgd = swapper_pg_dir,
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.mm_users = ATOMIC_INIT(2),

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