From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joerg Roedel Subject: Re: [Patch v2 3/9] iommu/amd: make several functions globally seen Date: Fri, 27 Nov 2015 12:06:09 +0100 Message-ID: <20151127110609.GB24300@8bytes.org> References: <1446811851-20623-1-git-send-email-bhe@redhat.com> <1446811851-20623-4-git-send-email-bhe@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1446811851-20623-4-git-send-email-bhe-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Baoquan He Cc: iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org List-Id: iommu@lists.linux-foundation.org On Fri, Nov 06, 2015 at 08:10:45PM +0800, Baoquan He wrote: > They will be called later when copy old dev/irq tables. It's better to use them > then call iommu_flush_all_caches() since iommu_flush_all_caches() will > iterate many empty table entries. You only flush all table entries on old AMD IOMMUs. Newer ones have a flush_all command that is used when available. Besides that, the AMD IOMMU hardware is usually fast so that even flushing all dte entries is not a bottleneck (it is done during suspend/resume, for example). Have you made different experiences? Joerg