From 2956c6644bfd9aab9f6b21a12e1bd75876d9dd73 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Sat, 19 May 2018 16:47:47 -0400 Subject: [PATCH] radix tree: Remove split/join code radix_tree_split and radix_tree_join were never used upstream. Remove them; if they're needed in future they will be replaced by XArray equivalents. Signed-off-by: Matthew Wilcox --- include/linux/radix-tree.h | 6 - lib/radix-tree.c | 171 +----------------- tools/testing/radix-tree/benchmark.c | 91 ---------- tools/testing/radix-tree/multiorder.c | 247 -------------------------- 4 files changed, 2 insertions(+), 513 deletions(-) diff --git a/include/linux/radix-tree.h b/include/linux/radix-tree.h index 7513d0df984b..44f9abdcb5ab 100644 --- a/include/linux/radix-tree.h +++ b/include/linux/radix-tree.h @@ -284,12 +284,6 @@ static inline void radix_tree_preload_end(void) preempt_enable(); } -int radix_tree_split_preload(unsigned old_order, unsigned new_order, gfp_t); -int radix_tree_split(struct radix_tree_root *, unsigned long index, - unsigned new_order); -int radix_tree_join(struct radix_tree_root *, unsigned long index, - unsigned new_order, void *); - void __rcu **idr_get_free(struct radix_tree_root *root, struct radix_tree_iter *iter, gfp_t gfp, unsigned long max); diff --git a/lib/radix-tree.c b/lib/radix-tree.c index c4c252185734..c52e0bef5264 100644 --- a/lib/radix-tree.c +++ b/lib/radix-tree.c @@ -415,28 +415,6 @@ int radix_tree_maybe_preload(gfp_t gfp_mask) } EXPORT_SYMBOL(radix_tree_maybe_preload); -#ifdef CONFIG_RADIX_TREE_MULTIORDER -/* - * Preload with enough objects to ensure that we can split a single entry - * of order @old_order into many entries of size @new_order - */ -int radix_tree_split_preload(unsigned int old_order, unsigned int new_order, - gfp_t gfp_mask) -{ - unsigned top = 1 << (old_order % RADIX_TREE_MAP_SHIFT); - unsigned layers = (old_order / RADIX_TREE_MAP_SHIFT) - - (new_order / RADIX_TREE_MAP_SHIFT); - unsigned nr = 0; - - WARN_ON_ONCE(!gfpflags_allow_blocking(gfp_mask)); - BUG_ON(new_order >= old_order); - - while (layers--) - nr = nr * RADIX_TREE_MAP_SIZE + 1; - return __radix_tree_preload(gfp_mask, top * nr); -} -#endif - /* * The same as function above, but preload number of nodes required to insert * (1 << order) continuous naturally-aligned elements. @@ -1111,8 +1089,8 @@ EXPORT_SYMBOL(radix_tree_replace_slot); * @slot: pointer to slot * @item: new item to store in the slot. * - * For use with radix_tree_split() and radix_tree_for_each_slot(). - * Caller must hold tree write locked across split and replacement. + * For use with radix_tree_for_each_slot(). + * Caller must hold tree write locked. */ void radix_tree_iter_replace(struct radix_tree_root *root, const struct radix_tree_iter *iter, @@ -1121,151 +1099,6 @@ void radix_tree_iter_replace(struct radix_tree_root *root, __radix_tree_replace(root, iter->node, slot, item); } -#ifdef CONFIG_RADIX_TREE_MULTIORDER -/** - * radix_tree_join - replace multiple entries with one multiorder entry - * @root: radix tree root - * @index: an index inside the new entry - * @order: order of the new entry - * @item: new entry - * - * Call this function to replace several entries with one larger entry. - * The existing entries are presumed to not need freeing as a result of - * this call. - * - * The replacement entry will have all the tags set on it that were set - * on any of the entries it is replacing. - */ -int radix_tree_join(struct radix_tree_root *root, unsigned long index, - unsigned order, void *item) -{ - struct radix_tree_node *node; - void __rcu **slot; - int error; - - BUG_ON(radix_tree_is_internal_node(item)); - - error = __radix_tree_create(root, index, order, &node, &slot); - if (!error) - error = insert_entries(node, slot, item, order, true); - if (error > 0) - error = 0; - - return error; -} - -/** - * radix_tree_split - Split an entry into smaller entries - * @root: radix tree root - * @index: An index within the large entry - * @order: Order of new entries - * - * Call this function as the first step in replacing a multiorder entry - * with several entries of lower order. After this function returns, - * loop over the relevant portion of the tree using radix_tree_for_each_slot() - * and call radix_tree_iter_replace() to set up each new entry. - * - * The tags from this entry are replicated to all the new entries. - * - * The radix tree should be locked against modification during the entire - * replacement operation. Lock-free lookups will see RADIX_TREE_RETRY which - * should prompt RCU walkers to restart the lookup from the root. - */ -int radix_tree_split(struct radix_tree_root *root, unsigned long index, - unsigned order) -{ - struct radix_tree_node *parent, *node, *child; - void __rcu **slot; - unsigned int offset, end; - unsigned n, tag, tags = 0; - gfp_t gfp = root_gfp_mask(root); - - if (!__radix_tree_lookup(root, index, &parent, &slot)) - return -ENOENT; - if (!parent) - return -ENOENT; - - offset = get_slot_offset(parent, slot); - - for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++) - if (tag_get(parent, tag, offset)) - tags |= 1 << tag; - - for (end = offset + 1; end < RADIX_TREE_MAP_SIZE; end++) { - if (!xa_is_sibling(rcu_dereference_raw(parent->slots[end]))) - break; - for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++) - if (tags & (1 << tag)) - tag_set(parent, tag, end); - /* rcu_assign_pointer ensures tags are set before RETRY */ - rcu_assign_pointer(parent->slots[end], RADIX_TREE_RETRY); - } - rcu_assign_pointer(parent->slots[offset], RADIX_TREE_RETRY); - parent->nr_values -= (end - offset); - - if (order == parent->shift) - return 0; - if (order > parent->shift) { - while (offset < end) - offset += insert_entries(parent, &parent->slots[offset], - RADIX_TREE_RETRY, order, true); - return 0; - } - - node = parent; - - for (;;) { - if (node->shift > order) { - child = radix_tree_node_alloc(gfp, node, root, - node->shift - RADIX_TREE_MAP_SHIFT, - offset, 0, 0); - if (!child) - goto nomem; - if (node != parent) { - node->count++; - rcu_assign_pointer(node->slots[offset], - node_to_entry(child)); - for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++) - if (tags & (1 << tag)) - tag_set(node, tag, offset); - } - - node = child; - offset = 0; - continue; - } - - n = insert_entries(node, &node->slots[offset], - RADIX_TREE_RETRY, order, false); - BUG_ON(n > RADIX_TREE_MAP_SIZE); - - for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++) - if (tags & (1 << tag)) - tag_set(node, tag, offset); - offset += n; - - while (offset == RADIX_TREE_MAP_SIZE) { - if (node == parent) - break; - offset = node->offset; - child = node; - node = node->parent; - rcu_assign_pointer(node->slots[offset], - node_to_entry(child)); - offset++; - } - if ((node == parent) && (offset == end)) - return 0; - } - - nomem: - /* Shouldn't happen; did user forget to preload? */ - /* TODO: free all the allocated nodes */ - WARN_ON(1); - return -ENOMEM; -} -#endif - static void node_tag_set(struct radix_tree_root *root, struct radix_tree_node *node, unsigned int tag, unsigned int offset) diff --git a/tools/testing/radix-tree/benchmark.c b/tools/testing/radix-tree/benchmark.c index 99c40f3ed133..35741b9c2a4a 100644 --- a/tools/testing/radix-tree/benchmark.c +++ b/tools/testing/radix-tree/benchmark.c @@ -146,90 +146,6 @@ static void benchmark_size(unsigned long size, unsigned long step, int order) rcu_barrier(); } -static long long __benchmark_split(unsigned long index, - int old_order, int new_order) -{ - struct timespec start, finish; - long long nsec; - RADIX_TREE(tree, GFP_ATOMIC); - - item_insert_order(&tree, index, old_order); - - clock_gettime(CLOCK_MONOTONIC, &start); - radix_tree_split(&tree, index, new_order); - clock_gettime(CLOCK_MONOTONIC, &finish); - nsec = (finish.tv_sec - start.tv_sec) * NSEC_PER_SEC + - (finish.tv_nsec - start.tv_nsec); - - item_kill_tree(&tree); - - return nsec; - -} - -static void benchmark_split(unsigned long size, unsigned long step) -{ - int i, j, idx; - long long nsec = 0; - - - for (idx = 0; idx < size; idx += step) { - for (i = 3; i < 11; i++) { - for (j = 0; j < i; j++) { - nsec += __benchmark_split(idx, i, j); - } - } - } - - printv(2, "Size %8ld, step %8ld, split time %10lld ns\n", - size, step, nsec); - -} - -static long long __benchmark_join(unsigned long index, - unsigned order1, unsigned order2) -{ - unsigned long loc; - struct timespec start, finish; - long long nsec; - void *item, *item2 = item_create(index + 1, order1); - RADIX_TREE(tree, GFP_KERNEL); - - item_insert_order(&tree, index, order2); - item = radix_tree_lookup(&tree, index); - - clock_gettime(CLOCK_MONOTONIC, &start); - radix_tree_join(&tree, index + 1, order1, item2); - clock_gettime(CLOCK_MONOTONIC, &finish); - nsec = (finish.tv_sec - start.tv_sec) * NSEC_PER_SEC + - (finish.tv_nsec - start.tv_nsec); - - loc = find_item(&tree, item); - if (loc == -1) - free(item); - - item_kill_tree(&tree); - - return nsec; -} - -static void benchmark_join(unsigned long step) -{ - int i, j, idx; - long long nsec = 0; - - for (idx = 0; idx < 1 << 10; idx += step) { - for (i = 1; i < 15; i++) { - for (j = 0; j < i; j++) { - nsec += __benchmark_join(idx, i, j); - } - } - } - - printv(2, "Size %8d, step %8ld, join time %10lld ns\n", - 1 << 10, step, nsec); -} - void benchmark(void) { unsigned long size[] = {1 << 10, 1 << 20, 0}; @@ -247,11 +163,4 @@ void benchmark(void) for (c = 0; size[c]; c++) for (s = 0; step[s]; s++) benchmark_size(size[c], step[s] << 9, 9); - - for (c = 0; size[c]; c++) - for (s = 0; step[s]; s++) - benchmark_split(size[c], step[s]); - - for (s = 0; step[s]; s++) - benchmark_join(step[s]); } diff --git a/tools/testing/radix-tree/multiorder.c b/tools/testing/radix-tree/multiorder.c index 0e0ff26c9bcb..221e042d1b89 100644 --- a/tools/testing/radix-tree/multiorder.c +++ b/tools/testing/radix-tree/multiorder.c @@ -356,251 +356,6 @@ void multiorder_tagged_iteration(void) item_kill_tree(&tree); } -/* - * Basic join checks: make sure we can't find an entry in the tree after - * a larger entry has replaced it - */ -static void multiorder_join1(unsigned long index, - unsigned order1, unsigned order2) -{ - unsigned long loc; - void *item, *item2 = item_create(index + 1, order1); - RADIX_TREE(tree, GFP_KERNEL); - - item_insert_order(&tree, index, order2); - item = radix_tree_lookup(&tree, index); - radix_tree_join(&tree, index + 1, order1, item2); - loc = find_item(&tree, item); - if (loc == -1) - free(item); - item = radix_tree_lookup(&tree, index + 1); - assert(item == item2); - item_kill_tree(&tree); -} - -/* - * Check that the accounting of value entries is handled correctly - * by joining a value entry to a normal pointer. - */ -static void multiorder_join2(unsigned order1, unsigned order2) -{ - RADIX_TREE(tree, GFP_KERNEL); - struct radix_tree_node *node; - void *item1 = item_create(0, order1); - void *item2; - - item_insert_order(&tree, 0, order2); - radix_tree_insert(&tree, 1 << order2, xa_mk_value(5)); - item2 = __radix_tree_lookup(&tree, 1 << order2, &node, NULL); - assert(item2 == xa_mk_value(5)); - assert(node->nr_values == 1); - - item2 = radix_tree_lookup(&tree, 0); - free(item2); - - radix_tree_join(&tree, 0, order1, item1); - item2 = __radix_tree_lookup(&tree, 1 << order2, &node, NULL); - assert(item2 == item1); - assert(node->nr_values == 0); - item_kill_tree(&tree); -} - -/* - * This test revealed an accounting bug for value entries at one point. - * Nodes were being freed back into the pool with an elevated exception count - * by radix_tree_join() and then radix_tree_split() was failing to zero the - * count of value entries. - */ -static void multiorder_join3(unsigned int order) -{ - RADIX_TREE(tree, GFP_KERNEL); - struct radix_tree_node *node; - void **slot; - struct radix_tree_iter iter; - unsigned long i; - - for (i = 0; i < (1 << order); i++) { - radix_tree_insert(&tree, i, xa_mk_value(5)); - } - - radix_tree_join(&tree, 0, order, xa_mk_value(7)); - rcu_barrier(); - - radix_tree_split(&tree, 0, 0); - - radix_tree_for_each_slot(slot, &tree, &iter, 0) { - radix_tree_iter_replace(&tree, &iter, slot, xa_mk_value(5)); - } - - __radix_tree_lookup(&tree, 0, &node, NULL); - assert(node->nr_values == node->count); - - item_kill_tree(&tree); -} - -static void multiorder_join(void) -{ - int i, j, idx; - - for (idx = 0; idx < 1024; idx = idx * 2 + 3) { - for (i = 1; i < 15; i++) { - for (j = 0; j < i; j++) { - multiorder_join1(idx, i, j); - } - } - } - - for (i = 1; i < 15; i++) { - for (j = 0; j < i; j++) { - multiorder_join2(i, j); - } - } - - for (i = 3; i < 10; i++) { - multiorder_join3(i); - } -} - -static void check_mem(unsigned old_order, unsigned new_order, unsigned alloc) -{ - struct radix_tree_preload *rtp = &radix_tree_preloads; - if (rtp->nr != 0) - printv(2, "split(%u %u) remaining %u\n", old_order, new_order, - rtp->nr); - /* - * Can't check for equality here as some nodes may have been - * RCU-freed while we ran. But we should never finish with more - * nodes allocated since they should have all been preloaded. - */ - if (nr_allocated > alloc) - printv(2, "split(%u %u) allocated %u %u\n", old_order, new_order, - alloc, nr_allocated); -} - -static void __multiorder_split(int old_order, int new_order) -{ - RADIX_TREE(tree, GFP_ATOMIC); - void **slot; - struct radix_tree_iter iter; - unsigned alloc; - struct item *item; - - radix_tree_preload(GFP_KERNEL); - assert(item_insert_order(&tree, 0, old_order) == 0); - radix_tree_preload_end(); - - /* Wipe out the preloaded cache or it'll confuse check_mem() */ - radix_tree_cpu_dead(0); - - item = radix_tree_tag_set(&tree, 0, 2); - - radix_tree_split_preload(old_order, new_order, GFP_KERNEL); - alloc = nr_allocated; - radix_tree_split(&tree, 0, new_order); - check_mem(old_order, new_order, alloc); - radix_tree_for_each_slot(slot, &tree, &iter, 0) { - radix_tree_iter_replace(&tree, &iter, slot, - item_create(iter.index, new_order)); - } - radix_tree_preload_end(); - - item_kill_tree(&tree); - free(item); -} - -static void __multiorder_split2(int old_order, int new_order) -{ - RADIX_TREE(tree, GFP_KERNEL); - void **slot; - struct radix_tree_iter iter; - struct radix_tree_node *node; - void *item; - - __radix_tree_insert(&tree, 0, old_order, xa_mk_value(5)); - - item = __radix_tree_lookup(&tree, 0, &node, NULL); - assert(item == xa_mk_value(5)); - assert(node->nr_values > 0); - - radix_tree_split(&tree, 0, new_order); - radix_tree_for_each_slot(slot, &tree, &iter, 0) { - radix_tree_iter_replace(&tree, &iter, slot, - item_create(iter.index, new_order)); - } - - item = __radix_tree_lookup(&tree, 0, &node, NULL); - assert(item != xa_mk_value(5)); - assert(node->nr_values == 0); - - item_kill_tree(&tree); -} - -static void __multiorder_split3(int old_order, int new_order) -{ - RADIX_TREE(tree, GFP_KERNEL); - void **slot; - struct radix_tree_iter iter; - struct radix_tree_node *node; - void *item; - - __radix_tree_insert(&tree, 0, old_order, xa_mk_value(5)); - - item = __radix_tree_lookup(&tree, 0, &node, NULL); - assert(item == xa_mk_value(5)); - assert(node->nr_values > 0); - - radix_tree_split(&tree, 0, new_order); - radix_tree_for_each_slot(slot, &tree, &iter, 0) { - radix_tree_iter_replace(&tree, &iter, slot, xa_mk_value(7)); - } - - item = __radix_tree_lookup(&tree, 0, &node, NULL); - assert(item == xa_mk_value(7)); - assert(node->nr_values > 0); - - item_kill_tree(&tree); - - __radix_tree_insert(&tree, 0, old_order, xa_mk_value(5)); - - item = __radix_tree_lookup(&tree, 0, &node, NULL); - assert(item == xa_mk_value(5)); - assert(node->nr_values > 0); - - radix_tree_split(&tree, 0, new_order); - radix_tree_for_each_slot(slot, &tree, &iter, 0) { - if (iter.index == (1 << new_order)) - radix_tree_iter_replace(&tree, &iter, slot, - xa_mk_value(7)); - else - radix_tree_iter_replace(&tree, &iter, slot, NULL); - } - - item = __radix_tree_lookup(&tree, 1 << new_order, &node, NULL); - assert(item == xa_mk_value(7)); - assert(node->count == node->nr_values); - do { - node = node->parent; - if (!node) - break; - assert(node->count == 1); - assert(node->nr_values == 0); - } while (1); - - item_kill_tree(&tree); -} - -static void multiorder_split(void) -{ - int i, j; - - for (i = 3; i < 11; i++) - for (j = 0; j < i; j++) { - __multiorder_split(i, j); - __multiorder_split2(i, j); - __multiorder_split3(i, j); - } -} - static void multiorder_account(void) { RADIX_TREE(tree, GFP_KERNEL); @@ -702,8 +457,6 @@ void multiorder_checks(void) multiorder_tag_tests(); multiorder_iteration(); multiorder_tagged_iteration(); - multiorder_join(); - multiorder_split(); multiorder_account(); multiorder_iteration_race();