lkml.org 
[lkml]   [1999]   [Mar]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: disk head scheduling
On Sun, Mar 21, 1999 at 09:41:21AM -0800, Linus Torvalds wrote:
> Anyway, the problem with the basic block interface is that it is currently
> locked to using the major number of a device as the index into the queue.
> That wasn't really how it was _meant_ to be: it was just that the early
> devices had a nice "one major number for one controller" setup, so the 1:1
> mapping was the simplest one.
>
> These days people are so used to "major number indexes the request queue",
> that people don't even realize that it wasn't meant to be taken that way.
> For devices with multiple request queues for the same major number there
> should simply be a mapping function or something simple like that. But
> nobody has ever gotten quite interested enough to clean this up, and
> instead we've just added more and more special cases to ll_rw_block.c.

Is this as simple as adding a function ptr to blk_dev_struct, and get_request
calling it if it is non-NULL?

Another quick Q: attempt_merge() is just done to reduce usage of request
structures, right?

-- arvind

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:50    [W:0.161 / U:0.100 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site