lkml.org 
[lkml]   [2003]   [Mar]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: reducing stack usage in v4l?
On Wed, Mar 05, 2003 at 10:15:52AM +0100, Gerd Knorr wrote:
> But when looking at the disasm output it is obvious that it isn't true
> (at least with gcc 3.2). On the other hand it is common practice in
> many drivers, there must be a reason for that, no? Any chance this
> used to work with older gcc versions?

I don't believe so - I seem to remember looking at gcc 2.95 and finding
the same annoying behaviour.

> Not sure what is the best idea to fix that. Don't like the kmalloc
> idea that much. The individual structs are not huge, the real problem
> is that many of them are allocated and only few are needed. Any
> chance to tell gcc that it should allocate block-local variables at
> the start block not at the start of the function?

Not a particularly clean idea, but maybe creating a union of the
structures and putting that on the stack? (ie, doing what GCC should
be doing in the first place.)

--
Russell King (rmk@arm.linux.org.uk) The developer of ARM Linux
http://www.arm.linux.org.uk/personal/aboutme.html

-
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: 2005-03-22 13:33    [from the cache]
©2003-2014 Jasper Spaans. Advertise on this site