Messages in this thread | | | Date | Thu, 10 Aug 2006 09:11:29 -0700 | From | "Paul E. McKenney" <> | Subject | Re: [PATCH] memory ordering in __kfifo primitives |
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On Thu, Aug 10, 2006 at 05:47:22PM +0200, Stelian Pop wrote: > Le jeudi 10 août 2006 à 08:39 -0700, Paul E. McKenney a écrit : > > On Thu, Aug 10, 2006 at 04:26:53PM +0200, Stelian Pop wrote: > > > Le jeudi 10 août 2006 à 06:41 -0700, Paul E. McKenney a écrit : > > > > > > > I am happy to go either way -- the patch with the memory barriers > > > > (which does have the side-effect of slowing down kfifo_get() and > > > > kfifo_put(), by the way), or a patch removing the comments saying > > > > that it is OK to invoke __kfifo_get() and __kfifo_put() without > > > > locking. > > > > > > > > Any other thoughts on which is better? (1) the memory barriers or > > > > (2) requiring the caller hold appropriate locks across calls to > > > > __kfifo_get() and __kfifo_put()? > > > > > > If someone wants to use explicit locking, he/she can go with kfifo_get() > > > instead of the __ version. > > > > However, the kfifo_get()/kfifo_put() interfaces use the internal lock, > > ... and the internal lock can be supplied by the user at kfifo_alloc() > time.
Would that really work for them? Looks to me like it would result in self-deadlock if they passed in session->lock.
Or did you have something else in mind for them?
These are the __kfifo_get() and __kfifo_put() uses in:
drivers/scsi/iscsi_tcp.c drivers/scsi/libiscsi.c drivers/infiniband/ulp/iser/iser_initiator.c
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