Re: [patch 00/2] improve .text size on gcc 4.0 and newer compilers

[Ingo Molnar]

* Adrian Bunk <bunk@xxxxxxxxx> wrote:

> It won't be dropped on the floor indefinitely.
> 
> "I do plan to look at this" means that I'd currently estimate this 
> being 2.6.19 stuff.

you must be kidding ...

> Yes that's one year from now, but we need it properly analyzed and 
> tested before getting it into Linus' tree, and I do really want it 
> untangled from and therefore after 4k stacks.

you are really using the wrong technology for this.

look at the latency tracing patch i posted today: it includes a feature 
that prints the worst-case stack footprint _as it happens_, and thus 
allows the mapping of such effects in a very efficient and very 
practical way. As it works on a live system, and profiles live function 
traces, it goes through function pointers and irq entry nesting effects 
too. We could perhaps put that into Fedora for a while and get the 
worst-case footprints mapped.

in fact i've been running this feature in the -rt kernel for quite some 
time, and it enabled the fixing of a couple of bad stack abusers, and it 
also told us what our current worst-case stack footprint is [when 4K 
stacks are enabled]: it's execve of an ELF binary.

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