Re: [PATCH 11/18] fs: Introduce per-bucket inode hash locks

From: Andi Kleen
Date: Mon Oct 18 2010 - 12:17:19 EST


Nick Piggin <npiggin@xxxxxxxxx> writes:
>
>> Providing
>> locking wrappers that are exactly what users need so they don't have
>> to care about it is, IMO, the right thing to do.
>
> Hiding the type of lock, and hiding the fact that it sets the low bit?
> I don't agree. We don't have synchronization in our data structures,
> where possible, because it is just restrictive or goes wrong when people
> don't think enough about the locking.

I fully agree. The old skb lists in networking made this mistake
long ago and it was a big problem, until people essentially stopped
using it (always using __ variants) and it was eventually removed.

Magic locking in data structures is usually a bad idea.

-Andi

--
ak@xxxxxxxxxxxxxxx -- Speaking for myself only.
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