Re: [PATCH] lookup_object: prioritize recently found objects
- From
Johannes Sixt <j.sixt@viscovery.net>
- Date
- May 3, 2013, 05:59 UTC
- Message-ID
- <5183522D.5060405@viscovery.net>
- In-Reply-To
- <20130502154618.GA18462@sigill.intra.peff.net>
Am 5/2/2013 17:46, schrieb Jeff King:
Show 11 quoted lines
> On Thu, May 02, 2013 at 09:05:01AM +0200, Johannes Sixt wrote: >> BTW, do you notice that the function is now modifying an object (the hash >> table) even though this is rather unexpected from a "lookup" function? > > I think this is fine. The function is conceptually constant from the > outside; callers don't even know about the hash table. They just know > that there is some mapping. It's similar to the way that lookup_commit > will lazily allocate the "struct commit". The callers do not care > whether it exists already or not; they care that at the end of the > function, they have a pointer to the commit. Everything else is an > implementation detail.
Can we be sure that the function is never invoked in concurrently from different threads? I attempted to audit code paths, but quickly gave up because I know too little about this machinery.
-- Hannes