diff options
Diffstat (limited to 'magic_buddy')
| -rw-r--r-- | magic_buddy/magic_buddy.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/magic_buddy/magic_buddy.c b/magic_buddy/magic_buddy.c index 6f9851b..f3dac00 100644 --- a/magic_buddy/magic_buddy.c +++ b/magic_buddy/magic_buddy.c @@ -78,6 +78,7 @@ static void *_allocate(size_t logsize, struct buddy *state) { memset(block, 0, sizeof(struct free_block)); return block; } + if (logsize == state->root_logsize) return 0; struct free_block *parent = _allocate(logsize + 1, state); struct free_block *buddy = buddy_of(parent, logsize, state); @@ -298,6 +299,7 @@ int shrink_buddy(size_t new_size, struct buddy *state) { // along the lhs path, until the root itself is free. size_t logsize = size2log(new_size, 0); + if ((1 << logsize) <= sizeof(struct free_block)) return 0; // First, just check whether we'll be able to do it: size_t virtual_root_logsize = state->root_logsize; @@ -313,10 +315,14 @@ int shrink_buddy(size_t new_size, struct buddy *state) { // It's possible! So go through and actually free the rhs children. while (state->root_logsize > logsize) { - if (isfree(state->base, state->root_logsize, state)) break; - struct free_block *rhs_child - = rhs_child_of(state->base, virtual_root_logsize, state); - memset(rhs_child, 0, sizeof(struct free_block)); + if (isfree(state->base, state->root_logsize, state)) { + pop(state->base); + push(state->base, state->root_logsize - 1, state); + } else { + struct free_block *rhs_child + = rhs_child_of(state->base, state->root_logsize, state); + memset(rhs_child, 0, sizeof(struct free_block)); + } state->root_logsize--; } state->root_logsize = logsize; |