From 315cc066b8ae8349a27887ad7a34e1916e9797fe Mon Sep 17 00:00:00 2001 From: Michel Lespinasse Date: Wed, 25 Sep 2019 16:46:07 -0700 Subject: [PATCH] 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 Acked-by: Peter Zijlstra (Intel) Cc: David Howells Cc: Davidlohr Bueso Cc: Uladzislau Rezki Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/x86/mm/pat_rbtree.c | 19 +++---------- drivers/block/drbd/drbd_interval.c | 29 +++----------------- include/linux/interval_tree_generic.h | 22 ++------------- include/linux/rbtree_augmented.h | 36 ++++++++++++++++++++++++- lib/rbtree_test.c | 37 ++++++++++++-------------- mm/mmap.c | 29 ++++++++++++-------- mm/vmalloc.c | 5 ++-- tools/include/linux/rbtree_augmented.h | 36 ++++++++++++++++++++++++- 8 files changed, 115 insertions(+), 98 deletions(-) diff --git a/arch/x86/mm/pat_rbtree.c b/arch/x86/mm/pat_rbtree.c index fa16036fa592..65ebe4b88f7c 100644 --- a/arch/x86/mm/pat_rbtree.c +++ b/arch/x86/mm/pat_rbtree.c @@ -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, diff --git a/drivers/block/drbd/drbd_interval.c b/drivers/block/drbd/drbd_interval.c index c58986556161..651bd0236a99 100644 --- a/drivers/block/drbd/drbd_interval.c +++ b/drivers/block/drbd/drbd_interval.c @@ -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 diff --git a/include/linux/interval_tree_generic.h b/include/linux/interval_tree_generic.h index 855476145fe1..aaa8a0767aa3 100644 --- a/include/linux/interval_tree_generic.h +++ b/include/linux/interval_tree_generic.h @@ -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 */ \ \ diff --git a/include/linux/rbtree_augmented.h b/include/linux/rbtree_augmented.h index 979941600082..e5937e387e02 100644 --- a/include/linux/rbtree_augmented.h +++ b/include/linux/rbtree_augmented.h @@ -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 diff --git a/lib/rbtree_test.c b/lib/rbtree_test.c index 62b8ee92643d..41ae3c7570d3 100644 --- a/lib/rbtree_test.c +++ b/lib/rbtree_test.c @@ -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); } } diff --git a/mm/mmap.c b/mm/mmap.c index f1e8c7f93e04..14b7da317ec0 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -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); } diff --git a/mm/vmalloc.c b/mm/vmalloc.c index fcadd3e25c0c..a3c70e275f4e 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -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); diff --git a/tools/include/linux/rbtree_augmented.h b/tools/include/linux/rbtree_augmented.h index de3a480204ba..4e8c4c76e9a2 100644 --- a/tools/include/linux/rbtree_augmented.h +++ b/tools/include/linux/rbtree_augmented.h @@ -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