On Thu, May 28, 2015 at 07:24:34AM -0400, Jeff Layton wrote: > > > 1) this is not done under a lock, so the non-atomic ++/-- is racy if > > > there are multiple swapons/swapoffs running concurrently on the same > > > xprt. Shouldn't those use an atomic? > > > > > > > It would be more appropriate to use atomics. It's a long time ago but I > > doubt I considered the possibility of multiple swapons racing at the > > time of implementation. Activation is typically a serialised task run > > from init. > > > > > 2) on enable, "swapper" is incremented and memalloc is set on the > > > socket. Do we need to do xs_set_memalloc every time swapon is called, > > > or only on a 0->1 swapper transition. > > > > > > > Every time because the static_key_slow_inc call is for the total number > > of connections. > > > > That still seems wrong. The static_key would still be active even if > you just did it once per xprt. >
True. As long as it is active while one swapfile exists then it's good. -- Mel Gorman SUSE Labs -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
