ngx_slab.c
void *
ngx_slab_alloc_locked(ngx_slab_pool_t *pool, size_t size)
{
size_t s;
uintptr_t p, n, m, mask, *bitmap;
ngx_uint_t i, slot, shift, map;
ngx_slab_page_t *page, *prev, *slots;
if (size >= ngx_slab_max_size) { // why not '>' ?
ngx_log_debug1(NGX_LOG_DEBUG_ALLOC, ngx_cycle->log, 0,
"slab alloc: %uz", size);