Messages in this thread |  | | Date | Sat, 17 Nov 2001 17:24:37 -0800 | From | William Lee Irwin III <> | Subject | Re: [RFC] tree-based bootmem |
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In my bootmem patch, I wrote: >> #define DIV_DN(x,n) (RND_DN(x,n) / (n)) >> #define DIV_UP(x,n) (RND_UP(x,n) / (n))
On Sun, Nov 18, 2001 at 12:58:19AM -0000, linux@horizon.com wrote: > Eww. I realize it's not performance-critical, but how about > the simpler > #define DIV_DN(x,n) ((x) / (n)) > #define DIV_UP(x,n) DIV_DN((x)+(n)-1, n) > > There are some alternate definitions of RND_UP available, as well: > #define RND_UP(x,n) (-RND_DN(-(x),n)) > or > #define RND_UP(x,n) (~(~(x) | (n)-1))
I hope you don't mind my Cc:'ing lkml in my reply.
These are both excellent points. In the interest of economy of CPU, I will follow your suggestions in the next installment (and list you in the changelog =).
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