Do some sanity checkings on the newly added radix tree code. It is meant to be removed after a while. Signed-off-by: Wu Fengguang --- mm/readahead.c | 24 ++++++++++++++++++++++++ 1 files changed, 24 insertions(+) --- linux-2.6.16-rc6-mm2.orig/mm/readahead.c +++ linux-2.6.16-rc6-mm2/mm/readahead.c @@ -80,6 +80,8 @@ enum ra_class { #include #include +#define DEBUG_READAHEAD_RADIXTREE + /* Read-ahead events to be accounted. */ enum ra_event { RA_EVENT_CACHE_MISS, /* read cache misses */ @@ -1515,6 +1517,13 @@ static unsigned long query_page_cache_se read_lock_irq(&mapping->tree_lock); index = radix_tree_scan_hole_backward(&mapping->page_tree, offset, ra_max); +#ifdef DEBUG_READAHEAD_RADIXTREE + WARN_ON(index > offset); + if (index != offset) + WARN_ON(!__find_page(mapping, index + 1)); + if (index && offset - index < ra_max) + WARN_ON(__find_page(mapping, index)); +#endif read_unlock_irq(&mapping->tree_lock); *remain = offset - index; @@ -1550,6 +1559,11 @@ static unsigned long query_page_cache_se struct radix_tree_node *node; node = radix_tree_cache_lookup_node(&mapping->page_tree, &cache, offset - count, 1); +#ifdef DEBUG_READAHEAD_RADIXTREE + if (node != radix_tree_lookup_node(&mapping->page_tree, + offset - count, 1)) + BUG(); +#endif if (!node) break; } @@ -1614,6 +1628,16 @@ static inline pgoff_t find_segtail(struc cond_resched(); read_lock_irq(&mapping->tree_lock); ra_index = radix_tree_scan_hole(&mapping->page_tree, index, max_scan); +#ifdef DEBUG_READAHEAD_RADIXTREE + BUG_ON(!__find_page(mapping, index)); + WARN_ON(ra_index < index); + if (ra_index != index && !__find_page(mapping, ra_index - 1)) + printk(KERN_ERR "radix_tree_scan_hole(index=%lu ra_index=%lu " + "max_scan=%lu nrpages=%lu) fooled!\n", + index, ra_index, max_scan, mapping->nrpages); + if (ra_index != ~0UL && ra_index - index < max_scan) + WARN_ON(__find_page(mapping, ra_index)); +#endif read_unlock_irq(&mapping->tree_lock); if (ra_index <= index + max_scan) --