Re: [PATCH] restart search at beggining of vmalloc address

[Nick Piggin <npiggin@suse.de>]

Excellent, thank you! Good catch

If you agree my previous patch was also good in combination with this one,
then I'll send them all to be merged.

Thanks,
Nick

On Thu, Nov 06, 2008 at 06:58:26PM -0200, Glauber Costa wrote:
> Current vmalloc restart search for a free area in case we
> can't find one. The reason is there are areas which are lazily
> freed, and could be possibly freed now. However, current implementation
> start searching the tree from the last failing address, which is
> pretty much by definition at the end of address space. So, we fail.
> 
> The proposal of this patch is to restart the search from the beginning
> of the requested vstart address. This fixes the regression in running
> KVM virtual machines for me, described in
> http://lkml.org/lkml/2008/10/28/349, caused by commit
> db64fe02258f1507e13fe5212a989922323685ce.
> 
> Signed-off-by: Glauber Costa <glommer@redhat.com>
> CC: Nick Piggin <npiggin@suse.de>
> ---
>  mm/vmalloc.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> index 7db493d..6fe2003 100644
> --- a/mm/vmalloc.c
> +++ b/mm/vmalloc.c
> @@ -378,6 +378,7 @@ found:
>  		if (!purged) {
>  			purge_vmap_area_lazy();
>  			purged = 1;
> +			addr = ALIGN(vstart, align);
>  			goto retry;
>  		}
>  		if (printk_ratelimit())
> -- 
> 1.5.6.5