augmented rbtree: add new RB_DECLARE_CALLBACKS_MAX macro

Add RB_DECLARE_CALLBACKS_MAX, which generates augmented rbtree callbacks
for the case where the augmented value is a scalar whose definition
follows a max(f(node)) pattern.  This actually covers all present uses of
RB_DECLARE_CALLBACKS, and saves some (source) code duplication in the
various RBCOMPUTE function definitions.

[walken@google.com: fix mm/vmalloc.c]
  Link: http://lkml.kernel.org/r/CANN689FXgK13wDYNh1zKxdipeTuALG4eKvKpsdZqKFJ-rvtGiQ@mail.gmail.com
[walken@google.com: re-add check to check_augmented()]
  Link: http://lkml.kernel.org/r/20190727022027.GA86863@google.com
Link: http://lkml.kernel.org/r/20190703040156.56953-3-walken@google.com
Signed-off-by: Michel Lespinasse <walken@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Uladzislau Rezki <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Michel Lespinasse 2019-09-25 16:46:07 -07:00 committed by Linus Torvalds
parent 444b8a83f1
commit 315cc066b8
8 changed files with 115 additions and 98 deletions

View File

@ -54,23 +54,10 @@ static u64 get_subtree_max_end(struct rb_node *node)
return ret;
}
static u64 compute_subtree_max_end(struct memtype *data)
{
u64 max_end = data->end, child_max_end;
#define NODE_END(node) ((node)->end)
child_max_end = get_subtree_max_end(data->rb.rb_right);
if (child_max_end > max_end)
max_end = child_max_end;
child_max_end = get_subtree_max_end(data->rb.rb_left);
if (child_max_end > max_end)
max_end = child_max_end;
return max_end;
}
RB_DECLARE_CALLBACKS(static, memtype_rb_augment_cb, struct memtype, rb,
u64, subtree_max_end, compute_subtree_max_end)
RB_DECLARE_CALLBACKS_MAX(static, memtype_rb_augment_cb,
struct memtype, rb, u64, subtree_max_end, NODE_END)
/* Find the first (lowest start addr) overlapping range from rb tree */
static struct memtype *memtype_rb_lowest_match(struct rb_root *root,

View File

@ -13,33 +13,10 @@ sector_t interval_end(struct rb_node *node)
return this->end;
}
/**
* compute_subtree_last - compute end of @node
*
* The end of an interval is the highest (start + (size >> 9)) value of this
* node and of its children. Called for @node and its parents whenever the end
* may have changed.
*/
static inline sector_t
compute_subtree_last(struct drbd_interval *node)
{
sector_t max = node->sector + (node->size >> 9);
#define NODE_END(node) ((node)->sector + ((node)->size >> 9))
if (node->rb.rb_left) {
sector_t left = interval_end(node->rb.rb_left);
if (left > max)
max = left;
}
if (node->rb.rb_right) {
sector_t right = interval_end(node->rb.rb_right);
if (right > max)
max = right;
}
return max;
}
RB_DECLARE_CALLBACKS(static, augment_callbacks, struct drbd_interval, rb,
sector_t, end, compute_subtree_last);
RB_DECLARE_CALLBACKS_MAX(static, augment_callbacks,
struct drbd_interval, rb, sector_t, end, NODE_END);
/**
* drbd_insert_interval - insert a new interval into a tree

View File

@ -30,26 +30,8 @@
\
/* Callbacks for augmented rbtree insert and remove */ \
\
static inline ITTYPE ITPREFIX ## _compute_subtree_last(ITSTRUCT *node) \
{ \
ITTYPE max = ITLAST(node), subtree_last; \
if (node->ITRB.rb_left) { \
subtree_last = rb_entry(node->ITRB.rb_left, \
ITSTRUCT, ITRB)->ITSUBTREE; \
if (max < subtree_last) \
max = subtree_last; \
} \
if (node->ITRB.rb_right) { \
subtree_last = rb_entry(node->ITRB.rb_right, \
ITSTRUCT, ITRB)->ITSUBTREE; \
if (max < subtree_last) \
max = subtree_last; \
} \
return max; \
} \
\
RB_DECLARE_CALLBACKS(static, ITPREFIX ## _augment, ITSTRUCT, ITRB, \
ITTYPE, ITSUBTREE, ITPREFIX ## _compute_subtree_last) \
RB_DECLARE_CALLBACKS_MAX(static, ITPREFIX ## _augment, \
ITSTRUCT, ITRB, ITTYPE, ITSUBTREE, ITLAST) \
\
/* Insert / remove interval nodes from the tree */ \
\

View File

@ -61,7 +61,7 @@ rb_insert_augmented_cached(struct rb_node *node,
}
/*
* Template for declaring augmented rbtree callbacks
* Template for declaring augmented rbtree callbacks (generic case)
*
* RBSTATIC: 'static' or empty
* RBNAME: name of the rb_augment_callbacks structure
@ -107,6 +107,40 @@ RBSTATIC const struct rb_augment_callbacks RBNAME = { \
.rotate = RBNAME ## _rotate \
};
/*
* Template for declaring augmented rbtree callbacks,
* computing RBAUGMENTED scalar as max(RBCOMPUTE(node)) for all subtree nodes.
*
* RBSTATIC: 'static' or empty
* RBNAME: name of the rb_augment_callbacks structure
* RBSTRUCT: struct type of the tree nodes
* RBFIELD: name of struct rb_node field within RBSTRUCT
* RBTYPE: type of the RBAUGMENTED field
* RBAUGMENTED: name of RBTYPE field within RBSTRUCT holding data for subtree
* RBCOMPUTE: name of function that returns the per-node RBTYPE scalar
*/
#define RB_DECLARE_CALLBACKS_MAX(RBSTATIC, RBNAME, RBSTRUCT, RBFIELD, \
RBTYPE, RBAUGMENTED, RBCOMPUTE) \
static inline RBTYPE RBNAME ## _compute_max(RBSTRUCT *node) \
{ \
RBSTRUCT *child; \
RBTYPE max = RBCOMPUTE(node); \
if (node->RBFIELD.rb_left) { \
child = rb_entry(node->RBFIELD.rb_left, RBSTRUCT, RBFIELD); \
if (child->RBAUGMENTED > max) \
max = child->RBAUGMENTED; \
} \
if (node->RBFIELD.rb_right) { \
child = rb_entry(node->RBFIELD.rb_right, RBSTRUCT, RBFIELD); \
if (child->RBAUGMENTED > max) \
max = child->RBAUGMENTED; \
} \
return max; \
} \
RB_DECLARE_CALLBACKS(RBSTATIC, RBNAME, RBSTRUCT, RBFIELD, \
RBTYPE, RBAUGMENTED, RBNAME ## _compute_max)
#define RB_RED 0
#define RB_BLACK 1

View File

@ -77,26 +77,10 @@ static inline void erase_cached(struct test_node *node, struct rb_root_cached *r
}
static inline u32 augment_recompute(struct test_node *node)
{
u32 max = node->val, child_augmented;
if (node->rb.rb_left) {
child_augmented = rb_entry(node->rb.rb_left, struct test_node,
rb)->augmented;
if (max < child_augmented)
max = child_augmented;
}
if (node->rb.rb_right) {
child_augmented = rb_entry(node->rb.rb_right, struct test_node,
rb)->augmented;
if (max < child_augmented)
max = child_augmented;
}
return max;
}
#define NODE_VAL(node) ((node)->val)
RB_DECLARE_CALLBACKS(static, augment_callbacks, struct test_node, rb,
u32, augmented, augment_recompute)
RB_DECLARE_CALLBACKS_MAX(static, augment_callbacks,
struct test_node, rb, u32, augmented, NODE_VAL)
static void insert_augmented(struct test_node *node,
struct rb_root_cached *root)
@ -238,7 +222,20 @@ static void check_augmented(int nr_nodes)
check(nr_nodes);
for (rb = rb_first(&root.rb_root); rb; rb = rb_next(rb)) {
struct test_node *node = rb_entry(rb, struct test_node, rb);
WARN_ON_ONCE(node->augmented != augment_recompute(node));
u32 subtree, max = node->val;
if (node->rb.rb_left) {
subtree = rb_entry(node->rb.rb_left, struct test_node,
rb)->augmented;
if (max < subtree)
max = subtree;
}
if (node->rb.rb_right) {
subtree = rb_entry(node->rb.rb_right, struct test_node,
rb)->augmented;
if (max < subtree)
max = subtree;
}
WARN_ON_ONCE(node->augmented != max);
}
}

View File

@ -289,9 +289,9 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
return retval;
}
static long vma_compute_subtree_gap(struct vm_area_struct *vma)
static inline unsigned long vma_compute_gap(struct vm_area_struct *vma)
{
unsigned long max, prev_end, subtree_gap;
unsigned long gap, prev_end;
/*
* Note: in the rare case of a VM_GROWSDOWN above a VM_GROWSUP, we
@ -299,14 +299,21 @@ static long vma_compute_subtree_gap(struct vm_area_struct *vma)
* an unmapped area; whereas when expanding we only require one.
* That's a little inconsistent, but keeps the code here simpler.
*/
max = vm_start_gap(vma);
gap = vm_start_gap(vma);
if (vma->vm_prev) {
prev_end = vm_end_gap(vma->vm_prev);
if (max > prev_end)
max -= prev_end;
if (gap > prev_end)
gap -= prev_end;
else
max = 0;
gap = 0;
}
return gap;
}
#ifdef CONFIG_DEBUG_VM_RB
static unsigned long vma_compute_subtree_gap(struct vm_area_struct *vma)
{
unsigned long max = vma_compute_gap(vma), subtree_gap;
if (vma->vm_rb.rb_left) {
subtree_gap = rb_entry(vma->vm_rb.rb_left,
struct vm_area_struct, vm_rb)->rb_subtree_gap;
@ -322,7 +329,6 @@ static long vma_compute_subtree_gap(struct vm_area_struct *vma)
return max;
}
#ifdef CONFIG_DEBUG_VM_RB
static int browse_rb(struct mm_struct *mm)
{
struct rb_root *root = &mm->mm_rb;
@ -428,8 +434,9 @@ static void validate_mm(struct mm_struct *mm)
#define validate_mm(mm) do { } while (0)
#endif
RB_DECLARE_CALLBACKS(static, vma_gap_callbacks, struct vm_area_struct, vm_rb,
unsigned long, rb_subtree_gap, vma_compute_subtree_gap)
RB_DECLARE_CALLBACKS_MAX(static, vma_gap_callbacks,
struct vm_area_struct, vm_rb,
unsigned long, rb_subtree_gap, vma_compute_gap)
/*
* Update augmented rbtree rb_subtree_gap values after vma->vm_start or
@ -439,8 +446,8 @@ RB_DECLARE_CALLBACKS(static, vma_gap_callbacks, struct vm_area_struct, vm_rb,
static void vma_gap_update(struct vm_area_struct *vma)
{
/*
* As it turns out, RB_DECLARE_CALLBACKS() already created a callback
* function that does exactly what we want.
* As it turns out, RB_DECLARE_CALLBACKS_MAX() already created
* a callback function that does exactly what we want.
*/
vma_gap_callbacks_propagate(&vma->vm_rb, NULL);
}

View File

@ -396,9 +396,8 @@ compute_subtree_max_size(struct vmap_area *va)
get_subtree_max_size(va->rb_node.rb_right));
}
RB_DECLARE_CALLBACKS(static, free_vmap_area_rb_augment_cb,
struct vmap_area, rb_node, unsigned long, subtree_max_size,
compute_subtree_max_size)
RB_DECLARE_CALLBACKS_MAX(static, free_vmap_area_rb_augment_cb,
struct vmap_area, rb_node, unsigned long, subtree_max_size, va_size)
static void purge_vmap_area_lazy(void);
static BLOCKING_NOTIFIER_HEAD(vmap_notify_list);

View File

@ -63,7 +63,7 @@ rb_insert_augmented_cached(struct rb_node *node,
}
/*
* Template for declaring augmented rbtree callbacks
* Template for declaring augmented rbtree callbacks (generic case)
*
* RBSTATIC: 'static' or empty
* RBNAME: name of the rb_augment_callbacks structure
@ -109,6 +109,40 @@ RBSTATIC const struct rb_augment_callbacks RBNAME = { \
.rotate = RBNAME ## _rotate \
};
/*
* Template for declaring augmented rbtree callbacks,
* computing RBAUGMENTED scalar as max(RBCOMPUTE(node)) for all subtree nodes.
*
* RBSTATIC: 'static' or empty
* RBNAME: name of the rb_augment_callbacks structure
* RBSTRUCT: struct type of the tree nodes
* RBFIELD: name of struct rb_node field within RBSTRUCT
* RBTYPE: type of the RBAUGMENTED field
* RBAUGMENTED: name of RBTYPE field within RBSTRUCT holding data for subtree
* RBCOMPUTE: name of function that returns the per-node RBTYPE scalar
*/
#define RB_DECLARE_CALLBACKS_MAX(RBSTATIC, RBNAME, RBSTRUCT, RBFIELD, \
RBTYPE, RBAUGMENTED, RBCOMPUTE) \
static inline RBTYPE RBNAME ## _compute_max(RBSTRUCT *node) \
{ \
RBSTRUCT *child; \
RBTYPE max = RBCOMPUTE(node); \
if (node->RBFIELD.rb_left) { \
child = rb_entry(node->RBFIELD.rb_left, RBSTRUCT, RBFIELD); \
if (child->RBAUGMENTED > max) \
max = child->RBAUGMENTED; \
} \
if (node->RBFIELD.rb_right) { \
child = rb_entry(node->RBFIELD.rb_right, RBSTRUCT, RBFIELD); \
if (child->RBAUGMENTED > max) \
max = child->RBAUGMENTED; \
} \
return max; \
} \
RB_DECLARE_CALLBACKS(RBSTATIC, RBNAME, RBSTRUCT, RBFIELD, \
RBTYPE, RBAUGMENTED, RBNAME ## _compute_max)
#define RB_RED 0
#define RB_BLACK 1