On Tue, Aug 20, 2019 at 06:59:39PM -0700, Matthew Wilcox wrote: >On Wed, Aug 21, 2019 at 09:22:44AM +0800, Wei Yang wrote: >> On Tue, Aug 20, 2019 at 05:54:17PM -0700, Matthew Wilcox wrote: >> >On Wed, Aug 21, 2019 at 08:52:34AM +0800, Wei Yang wrote: >> >> On Tue, Aug 20, 2019 at 10:26:29AM -0700, Matthew Wilcox wrote: >> >> >On Wed, Aug 14, 2019 at 11:19:37AM +0200, Vlastimil Babka wrote: >> >> >> On 8/14/19 8:57 AM, Wei Yang wrote: >> >> >> > On Tue, Aug 13, 2019 at 10:16:11PM -0700, Christoph Hellwig wrote: >> >> >> >>Btw, is there any good reason we don't use a list_head for vma linkage? >> >> >> > >> >> >> > Not sure, maybe there is some historical reason? >> >> >> >> >> >> Seems it was single-linked until 2010 commit 297c5eee3724 ("mm: make the vma >> >> >> list be doubly linked") and I guess it was just simpler to add the vm_prev link. >> >> >> >> >> >> Conversion to list_head might be an interesting project for some "advanced >> >> >> beginner" in the kernel :) >> >> > >> >> >I'm working to get rid of vm_prev and vm_next, so it would probably be >> >> >wasted effort. >> >> >> >> You mean replace it with list_head? >> > >> >No, replace the rbtree with a new tree. https://lwn.net/Articles/787629/ >> >> Sounds interesting. >> >> While I am not sure the plan is settled down, and how long it would take to >> replace the rb_tree with maple tree. I guess it would probably take some time >> to get merged upstream. >> >> IMHO, it would be good to have this cleanup in current kernel. Do you agree? > >The three cleanups you've posted are fine. Doing more work (ie the >list_head) seems like wasted effort to me. Ah, got your point. I misunderstand it. -- Wei Yang Help you, Help me