diff options
Diffstat (limited to '')
-rw-r--r-- | tools/perf/util/block-range.c | 329 |
1 files changed, 329 insertions, 0 deletions
diff --git a/tools/perf/util/block-range.c b/tools/perf/util/block-range.c new file mode 100644 index 000000000..f1451c987 --- /dev/null +++ b/tools/perf/util/block-range.c @@ -0,0 +1,329 @@ +// SPDX-License-Identifier: GPL-2.0 +#include "block-range.h" +#include "annotate.h" + +struct { + struct rb_root root; + u64 blocks; +} block_ranges; + +static void block_range__debug(void) +{ + /* + * XXX still paranoid for now; see if we can make this depend on + * DEBUG=1 builds. + */ +#if 1 + struct rb_node *rb; + u64 old = 0; /* NULL isn't executable */ + + for (rb = rb_first(&block_ranges.root); rb; rb = rb_next(rb)) { + struct block_range *entry = rb_entry(rb, struct block_range, node); + + assert(old < entry->start); + assert(entry->start <= entry->end); /* single instruction block; jump to a jump */ + + old = entry->end; + } +#endif +} + +struct block_range *block_range__find(u64 addr) +{ + struct rb_node **p = &block_ranges.root.rb_node; + struct rb_node *parent = NULL; + struct block_range *entry; + + while (*p != NULL) { + parent = *p; + entry = rb_entry(parent, struct block_range, node); + + if (addr < entry->start) + p = &parent->rb_left; + else if (addr > entry->end) + p = &parent->rb_right; + else + return entry; + } + + return NULL; +} + +static inline void rb_link_left_of_node(struct rb_node *left, struct rb_node *node) +{ + struct rb_node **p = &node->rb_left; + while (*p) { + node = *p; + p = &node->rb_right; + } + rb_link_node(left, node, p); +} + +static inline void rb_link_right_of_node(struct rb_node *right, struct rb_node *node) +{ + struct rb_node **p = &node->rb_right; + while (*p) { + node = *p; + p = &node->rb_left; + } + rb_link_node(right, node, p); +} + +/** + * block_range__create + * @start: branch target starting this basic block + * @end: branch ending this basic block + * + * Create all the required block ranges to precisely span the given range. + */ +struct block_range_iter block_range__create(u64 start, u64 end) +{ + struct rb_node **p = &block_ranges.root.rb_node; + struct rb_node *n, *parent = NULL; + struct block_range *next, *entry = NULL; + struct block_range_iter iter = { NULL, NULL }; + + while (*p != NULL) { + parent = *p; + entry = rb_entry(parent, struct block_range, node); + + if (start < entry->start) + p = &parent->rb_left; + else if (start > entry->end) + p = &parent->rb_right; + else + break; + } + + /* + * Didn't find anything.. there's a hole at @start, however @end might + * be inside/behind the next range. + */ + if (!*p) { + if (!entry) /* tree empty */ + goto do_whole; + + /* + * If the last node is before, advance one to find the next. + */ + n = parent; + if (entry->end < start) { + n = rb_next(n); + if (!n) + goto do_whole; + } + next = rb_entry(n, struct block_range, node); + + if (next->start <= end) { /* add head: [start...][n->start...] */ + struct block_range *head = malloc(sizeof(struct block_range)); + if (!head) + return iter; + + *head = (struct block_range){ + .start = start, + .end = next->start - 1, + .is_target = 1, + .is_branch = 0, + }; + + rb_link_left_of_node(&head->node, &next->node); + rb_insert_color(&head->node, &block_ranges.root); + block_range__debug(); + + iter.start = head; + goto do_tail; + } + +do_whole: + /* + * The whole [start..end] range is non-overlapping. + */ + entry = malloc(sizeof(struct block_range)); + if (!entry) + return iter; + + *entry = (struct block_range){ + .start = start, + .end = end, + .is_target = 1, + .is_branch = 1, + }; + + rb_link_node(&entry->node, parent, p); + rb_insert_color(&entry->node, &block_ranges.root); + block_range__debug(); + + iter.start = entry; + iter.end = entry; + goto done; + } + + /* + * We found a range that overlapped with ours, split if needed. + */ + if (entry->start < start) { /* split: [e->start...][start...] */ + struct block_range *head = malloc(sizeof(struct block_range)); + if (!head) + return iter; + + *head = (struct block_range){ + .start = entry->start, + .end = start - 1, + .is_target = entry->is_target, + .is_branch = 0, + + .coverage = entry->coverage, + .entry = entry->entry, + }; + + entry->start = start; + entry->is_target = 1; + entry->entry = 0; + + rb_link_left_of_node(&head->node, &entry->node); + rb_insert_color(&head->node, &block_ranges.root); + block_range__debug(); + + } else if (entry->start == start) + entry->is_target = 1; + + iter.start = entry; + +do_tail: + /* + * At this point we've got: @iter.start = [@start...] but @end can still be + * inside or beyond it. + */ + entry = iter.start; + for (;;) { + /* + * If @end is inside @entry, split. + */ + if (end < entry->end) { /* split: [...end][...e->end] */ + struct block_range *tail = malloc(sizeof(struct block_range)); + if (!tail) + return iter; + + *tail = (struct block_range){ + .start = end + 1, + .end = entry->end, + .is_target = 0, + .is_branch = entry->is_branch, + + .coverage = entry->coverage, + .taken = entry->taken, + .pred = entry->pred, + }; + + entry->end = end; + entry->is_branch = 1; + entry->taken = 0; + entry->pred = 0; + + rb_link_right_of_node(&tail->node, &entry->node); + rb_insert_color(&tail->node, &block_ranges.root); + block_range__debug(); + + iter.end = entry; + goto done; + } + + /* + * If @end matches @entry, done + */ + if (end == entry->end) { + entry->is_branch = 1; + iter.end = entry; + goto done; + } + + next = block_range__next(entry); + if (!next) + goto add_tail; + + /* + * If @end is in beyond @entry but not inside @next, add tail. + */ + if (end < next->start) { /* add tail: [...e->end][...end] */ + struct block_range *tail; +add_tail: + tail = malloc(sizeof(struct block_range)); + if (!tail) + return iter; + + *tail = (struct block_range){ + .start = entry->end + 1, + .end = end, + .is_target = 0, + .is_branch = 1, + }; + + rb_link_right_of_node(&tail->node, &entry->node); + rb_insert_color(&tail->node, &block_ranges.root); + block_range__debug(); + + iter.end = tail; + goto done; + } + + /* + * If there is a hole between @entry and @next, fill it. + */ + if (entry->end + 1 != next->start) { + struct block_range *hole = malloc(sizeof(struct block_range)); + if (!hole) + return iter; + + *hole = (struct block_range){ + .start = entry->end + 1, + .end = next->start - 1, + .is_target = 0, + .is_branch = 0, + }; + + rb_link_left_of_node(&hole->node, &next->node); + rb_insert_color(&hole->node, &block_ranges.root); + block_range__debug(); + } + + entry = next; + } + +done: + assert(iter.start->start == start && iter.start->is_target); + assert(iter.end->end == end && iter.end->is_branch); + + block_ranges.blocks++; + + return iter; +} + + +/* + * Compute coverage as: + * + * br->coverage / br->sym->max_coverage + * + * This ensures each symbol has a 100% spot, to reflect that each symbol has a + * most covered section. + * + * Returns [0-1] for coverage and -1 if we had no data what so ever or the + * symbol does not exist. + */ +double block_range__coverage(struct block_range *br) +{ + struct symbol *sym; + + if (!br) { + if (block_ranges.blocks) + return 0; + + return -1; + } + + sym = br->sym; + if (!sym) + return -1; + + return (double)br->coverage / symbol__annotation(sym)->max_coverage; +} |