Messages in this thread | | | Date | Wed, 12 Jan 2011 00:06:42 +1100 | Subject | Re: Important for fs devs: rcu-walk merged upstream | From | Nick Piggin <> |
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On Tuesday, January 11, 2011, Joel Becker <jlbec@evilplan.org> wrote: > On Sat, Jan 08, 2011 at 01:54:47PM +1100, Nick Piggin wrote: >> The rcu-walk stuff can be more tricky for your filesystem >> to take advantage of. >> >> If you supply a .d_revalidate, .permission, or .check_acl, >> then path walking is going to be slow and unscalable for >> you. > > Do you mean "as slow and unscalable as it has always been" or > "even slower now"? A quick look suggests the former, but I wanted to be > sure.
Yeah it should be about the same. Bit more complex code so it might be a bit slower. A few code and branch and cache improvements so it might be a bit faster. Refcounts on the same dentry become a bit less scalable for using lock instead of atomic. On the other hand dropping the ref on leaf denty doesn't require global lock.
It should not be urgent for 2.6.38. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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