From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Chen, Kenneth W" Date: Fri, 10 Mar 2006 17:29:20 +0000 Subject: RE: Fix race in the accessed/dirty bit handlers Message-Id: <200603101729.k2AHTJg04773@unix-os.sc.intel.com> List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org Zoltan Menyhart wrote on Friday, March 10, 2006 9:12 AM > Please consider the second issue I mentioned about the "itc": > Making sure that an external purge request will not be missed by our new > translation. See also on page 3:127: > > "The visibility of the itc instruction to generated purges (ptc.g, ptc.ga) must occur > before subsequent memory operations. From a software perspective, this is similar to > acquire semantics. Serialization is still required to observe the side-effects of the > translation being present." > > How to tell if this "visibility of the itc instruction to generated purges" > has already been established? > > I think a ";;" is not enough, this is why I propose this sequence: > > itc.d r25 > ;; > srlz.d > ld8 r18 = [r17] Thinking wild, I think we need a release semantics on the load. But such thing isn't available. - Ken