On Tue, Sep 10, 2013 at 12:47 AM, Seth Jennings <sjenning@xxxxxxxxxxxxxxxxxx> wrote: > On Fri, Sep 06, 2013 at 01:16:45PM +0800, Weijie Yang wrote: >> To avoid zswap store and reclaim functions called recursively, >> use GFP_NOIO instead of GFP_KERNEL >> >> Signed-off-by: Weijie Yang <weijie.yang@xxxxxxxxxxx> > > I agree with Bob to some degree that GFP_NOIO is a broadsword here. > Ideally, we'd like to continue allowing writeback of dirty file pages > and the like. However, I don't agree that a mutex is the way to do > this. > > My first thought was to use the PF_MEMALLOC task flag, but it is already > set for kswapd and any task doing direct reclaim. A new task flag would > work but I'm not sure how acceptable that would be. as GFP_NOIO is controversial and not the most appropriate method, I will keep GFP_KERNEL flag until we find a better way to resolve this problem. > In the meantime, this does do away with the possibility of very deep > recursion between the store and reclaim paths. > > Acked-by: Seth Jennings <sjenning@xxxxxxxxxxxxxxxxxx> > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>