lkml.org 
[lkml]   [2006]   [Jul]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
SubjectRe: [PATCH] blktrace: readahead support
From
Looking at the commit 

Date: Thu, 6 Jul 2006 08:03:28 +0000 (+0200)
X-Git-Url: http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=40359ccb836866435b03a0cb57345002b587d875

> --- a/block/blktrace.c
> +++ b/block/blktrace.c
..
> @@ -79,6 +79,8 @@ static u32 bio_act[3] __read_mostly = {
> (((rw) & (1 << BIO_RW_BARRIER)) >> (BIO_RW_BARRIER - 0))
> #define trace_sync_bit(rw) \
> (((rw) & (1 << BIO_RW_SYNC)) >> (BIO_RW_SYNC - 1))
> +#define trace_ahead_bit(rw) \
> + (((rw) & (1 << BIO_RW_AHEAD)) << (BIO_RW_AHEAD - 0))
>
> /*
> * The worker for the various blk_add_trace*() types. Fills out a


Than doesn't make sense, we are using the bit position in the BIO_RW_
name space twice instead of factoring it out like the other uses.

Looking at include/linux/bio.h line 147 we find
#define BIO_RW_AHEAD 1

So this is moving it from bit 1 (value 2) to bit 2 (value 4).

I think the shift should be << (2 - BIO_RW_AHEAD).

milton
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
\
 
 \ /
  Last update: 2006-07-10 07:49    [W:0.195 / U:0.632 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site