Re: the new VM

yodaiken
2000-09-25T15:22:17Z

On Mon, Sep 25, 2000 at 05:26:59PM +0200, Ingo Molnar wrote:
>
> On Mon, 25 Sep 2000, Andrea Arcangeli wrote:
>
> > > i think the GFP_USER case should do the oom logic within __alloc_pages(),
> >
> > What's the difference of implementing the logic outside alloc_pages?
> > Putting the logic inside looks not clean design to me.
>
> it gives consistency and simplicity. The allocators themselves do not have
> to care about oom.

There are many cases where it is simple to do:

if( alloc(r1) == fail) goto freeall
if( alloc(r2) == fail) goto freeall
if( alloc(r3) == fail) goto freeall

And the alloc functions don't know how to "freeall".

Perhaps it would be good to do an alloc_vec allocation in these cases.
alloc_vec[0].size = n;
..
alloc_vec[n].size = 0;
if(kmalloc_all(alloc_vec) == FAIL) return -ENOMEM;
else alloc_vec[i].ptr is the pointer.

--
---------------------------------------------------------
Victor Yodaiken
Finite State Machine Labs: The RTLinux Company.
www.fsmlabs.com www.rtlinux.com