Messages in this thread | | | Date | Thu, 12 Sep 2013 18:12:24 -0700 | Subject | Re: linux-next: manual merge of the akpm tree with Linus' tree | From | Linus Torvalds <> |
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On Thu, Sep 12, 2013 at 5:56 PM, Linus Torvalds <torvalds@linux-foundation.org> wrote: > > I'll walk through the code, it looked suspicious. Maybe there's > something subtle that makes it work, but I don't see it.
Btw, it's not just the DCACHE_LRU_LIST bit. The games with "nr_dentry_unused" look totally broken too. It's decremented in dentry_lru_isolate_shrink() for each dentry we remove, and then it is decremented *again* in shrink_dcache_sb() by the number of dentries we removed.
Maybe I'm confused, but the code sure looks more confused than I feel.
I would suggest keeping the same semantics for 'nr_dentry_unused'. Dentries are unused whether they are on the "real" LRU list or have been tagged with DCACHE_SHRINK_LIST. So moving from one list to the other does nothing. It's the "list_del_init()" that should trigger both 'nr_dentry_unused' and DCACHE_LRU_LIST bit-clearing.
In fact, maybe a helper function for _actually_ removing the thing from all lists, and adding them back. Right now there are "list_del_init()" and "list_add[_tail]()" calls sprinkled around in random places, mixed up with the new "list_lru_add()".
Damn, the code is too confused. I have to go to a highschool parent back-to-school meeting, so I won't get to this until maybe on a plane tomorrow. Al, can you please give this a look?
Linus
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