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dkim=pass header.d=Nvidia.com header.s=selector2 header.b=nuGoviNF; dmarc=pass (policy=reject) header.from=nvidia.com; spf=pass (imf30.hostedemail.com: domain of jgg@nvidia.com designates 40.107.220.41 as permitted sender) smtp.mailfrom=jgg@nvidia.com; arc=pass ("microsoft.com:s=arcselector9901:i=1") X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1660776609-81472 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 Wed, Aug 17, 2022 at 01:35:12PM -0700, John Hubbard wrote: > How's this look to you: > > collected = collect_longterm_unpinnable_pages(&movable_page_list, > nr_pages, pages); > if (collected == 0) > return 0; > > ret = migrate_longterm_unpinnable_pages(&movable_page_list, nr_pages, > pages); > > /* If we got here, we have some unpinnable pages... */ > > if (ret == 0) { > /* > * ...and we successfully migrated those pages. Which means that > * the caller should retry the operation now. > */ > ret = -EAGAIN; return -EAGAIN > } > > return ret; But why return 0 from the helper function in the first place? Jason