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dkim=pass header.d=Nvidia.com header.s=selector2 header.b=NIvXztrB; spf=none (imf26.hostedemail.com: domain of jhubbard@nvidia.com has no SPF policy when checking 40.107.236.81) smtp.mailfrom=jhubbard@nvidia.com; dmarc=pass (policy=quarantine) header.from=nvidia.com X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 751A520019FF X-HE-Tag: 1637052679-151472 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 11/15/21 05:57, Matthew Wilcox wrote: > On Mon, Nov 15, 2021 at 09:49:51PM +0800, Peter Xu wrote: >> Clean the code up by merging the device private/exclusive swap entry handling >> with the rest, then we merge the pte clear operation too. >> >> struct* page is defined in multiple places in the function, move it upward. > > Is that actually a good thing? There was a time when declaring Yes. It is a very good thing. Having multiple cases of shadowed variables (in this case I'm using programming language terminology, or what I remember it as, anyway) provides lots of opportunities to create hard-to-spot bugs. > variables more locally helped compilers with liveness analysis and > register allocation. Compilers are probably smarter now. > ...as long as the above checks out, and I see from Peter's response that we're OK. thanks, -- John Hubbard NVIDIA