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Tue, 14 Apr 2020 12:23:30 -0700 (PDT) Date: Tue, 14 Apr 2020 12:23:29 -0700 (PDT) X-X-Sender: rientjes@chino.kir.corp.google.com To: Christoph Hellwig Subject: Re: [rfc v2 3/6] dma-pool: dynamically expanding atomic pools In-Reply-To: <20200414064441.GC23359@lst.de> Message-ID: References: <20200410145520.17864-1-hdanton@sina.com> <20200414064441.GC23359@lst.de> User-Agent: Alpine 2.22 (DEB 394 2020-01-19) MIME-Version: 1.0 Cc: Tom Lendacky , Hillf Danton , "Singh, Brijesh" , "Grimm, Jon" , linux , iommu X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: David Rientjes via iommu Reply-To: David Rientjes Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On Tue, 14 Apr 2020, Christoph Hellwig wrote: > > I'll rely on Christoph to determine whether it makes sense to add some > > periodic scavening of the atomic pools, whether that's needed for this to > > be merged, or wheter we should enforce some maximum pool size. > > I don't really see the point. In fact the only part of the series > I feel uneasy about is the growing of the pools, because it already > adds a fair amount of complexity that we might not need for simple > things, but shrinking really doesn't make any sense. So I'm tempted > to not ever support shrinking, and even make growing optional code under > a new config variable. We'll also need a way to query the current size > through e.g. a debugfs file. > New debugfs file sounds good, I'll add it. If we want to disable dynamic expansion when the pool is depleted under a new config option, let me know. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu