Re: 2.5.75 as-iosched.c & asm-generic/div64.h breakage

[Andrew Morton]

Mikael Pettersson <[e-mail]> wrote:
>
> drivers/block/as-iosched.c: In function `as_update_iohist':
> drivers/block/as-iosched.c:840: warning: right shift count >= width of type
> drivers/block/as-iosched.c:840: warning: passing arg 1 of `__div64_32' from incompatible pointer type

You mean that code was in -mm for all those months and no ppc32 person
bothered testing it?  Bah.

Something like this?  (Could be sped up for 32-bit sector_t)

diff -puN drivers/block/as-iosched.c~as-do_div-fix drivers/block/as-iosched.c
--- 25/drivers/block/as-iosched.c~as-do_div-fix	Fri Jul 11 14:00:55 2003
+++ 25-akpm/drivers/block/as-iosched.c	Fri Jul 11 14:00:58 2003
@@ -836,8 +836,10 @@ static void as_update_iohist(struct as_i
 		aic->seek_samples += 256;
 		aic->seek_total += 256*seek_dist;
 		if (aic->seek_samples) {
-			aic->seek_mean = aic->seek_total + 128;
-			do_div(aic->seek_mean, aic->seek_samples);
+			u64 seek_mean = aic->seek_total + 128;
+
+			do_div(seek_mean, aic->seek_samples);
+			aic->seek_mean = seek_mean;
 		}
 		aic->seek_samples = (aic->seek_samples>>1)
 					+ (aic->seek_samples>>2);

_