Messages in this thread | | | Date | Tue, 24 Oct 2017 22:50:48 +0100 (BST) | From | James Simmons <> | Subject | Re: [lustre-devel] [PATCH 0/6] dcache/namei fixes for lustre |
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> >> This series is a revised version of two patches I sent > >> previously (one of which was sadly broken). > >> That patch has been broken into multiple parts for easy > >> review. The other is included unchanged as the last of > >> this series. > >> > >> I was drawn to look at this code due to the tests on > >> DCACHE_DISCONNECTED which are often wrong, and it turns out > >> they are used wrongly in lustre too. Fixing one led to some > >> clean-up. Fixing the other is straight forward. > >> > >> A particular change here from the previous posting is > >> the first patch which tests for DCACHE_PAR_LOOKUP in ll_dcompare(). > >> Without this patch, two threads can be looking up the same > >> name in a given directory in parallel. This parallelism lead > >> to my concerns about needing improved locking in ll_splice_alias(). > >> Instead of improving the locking, I now avoid the need for it > >> by fixing ll_dcompare. > >> > >> This code passes basic "smoke tests". > >> > >> Note that the cast to "struct dentry *" in the first patch is because > >> we have a "const struct dentry *" but d_in_lookup() requires a > >> pointer to a non-const structure. I'll send a separate patch to > >> change d_in_lookup(). > > > > To let you know this patch has been under going testing and we have a > > ticket open to track the progess: > > > > https://jira.hpdd.intel.com/browse/LU-9868 > > > > Your patch did reveal that a piece of a fix landed earlier is missing :-( > > So currently the client can oops. I will send the fix shortly but this > > work will have to rebased after. As soon as we can get some cycles we will > > figure out what is going on. Thanks for helping out. > > Hi, > what happened about this? I had a look around the ticket and couldn't > find anything about an oops. If there is still a problem I'd be very > happy to help work out what it is - but I don't know where to look.
The oops is specific to the in kernel client. Some where along the way the calls to ll_d_init() were removed from ll_splice_alias(). It was unnoticed until your patch came along. I do have a fix that I will be pushing to the next staging tree very shortly.
I have been testing the patch series and for me I don't see any issue. Our test suite is reporting failures with this patch which I'm attempting to figure out how to reproduce locally on my test system. Once I have a reproducer I can send it to you.
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