Messages in this thread | | | Date | Thu, 13 May 2010 23:28:50 -0300 | From | Cesar Eduardo Barros <> | Subject | Re: [PATCH] radix-tree: fix radix_tree_prev_hole underflow case |
| |
Em 13-05-2010 23:15, Wu Fengguang escreveu: > On Fri, May 14, 2010 at 10:05:24AM +0800, Cesar Eduardo Barros wrote: >> radix_tree_prev_hole() used LONG_MAX to detect underflow; however, >> ULONG_MAX is clearly what was intended, both here and by its only user >> (count_history_pages at mm/readahead.c). > > Good catch, thanks! I actually have a more smart > radix_tree_prev_hole() that uses ULONG_MAX.
I saw it already ([PATCH 14/16] radixtree: speed up the search for hole), but it misses the LONG_MAX in the documentation comment.
> Andrew, fortunately this bug has little impact on readahead.
I agree, if I read it correctly it should only have any impact either when very near LONG_MAX or in the unlikely case that there is no hole at ULONG_MAX. And even then, the impact should be limited.
-- Cesar Eduardo Barros cesarb@cesarb.net cesar.barros@gmail.com
| |