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bh=ZNc8bm9IXLjaHBXvEHJFswdMKmxe0hW5uSNwNJAOouQ=; b=hgHpK3EVAzW1ED/n9tr/TIP5OJvGBU/Msmf1xjZfEr8JEVE9MTcQCbnZKiVH9dh8bRnwwJ YGZpZ2o7L/SVYjcohICPCX3BssC0U6Q6K+I3oMiuGdolPVsRFRDBrTEBHbdOmTddAxH5Fh XYkPNf/I8ac914AA9iglUZubr9GTfQE= X-Stat-Signature: gqj46gfc84fmdqnznrc7ypu3x37wwk6x X-Rspamd-Queue-Id: D91A8C006A X-Rspam-User: Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2022-7-12 header.b=f1JQwet4; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=Gp2H2+nc; spf=pass (imf10.hostedemail.com: domain of mike.kravetz@oracle.com designates 205.220.165.32 as permitted sender) smtp.mailfrom=mike.kravetz@oracle.com; dmarc=pass (policy=none) header.from=oracle.com; arc=pass ("microsoft.com:s=arcselector9901:i=1") X-Rspamd-Server: rspam08 X-HE-Tag: 1662483916-387204 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 09/04/22 22:15, Matthew Wilcox wrote: > On Sun, Sep 04, 2022 at 02:02:41PM +0000, Cheng Li wrote: > > To handle discontiguity case, mem_map_next() has a parameter named > > `offset`. As a function caller, one would be confused why "get > > next entry" needs a parameter named "offset". The other drawback of > > mem_map_next() is that the callers must take care of the map between > > parameter "iter" and "offset", otherwise we may get an hole or > > duplication during iteration. So we use mem_map_offset instead of > > mem_map_next. > > I think we should go further and get rid of mem_map_offset(). > nth_page() is now more efficient than mem_map_offset(). Agree. However, IIUC nth_page() will 'almost' always be more efficient. The only exception is unlikely configuration where CONFIG_SPARSEMEM && !CONFIG_SPARSEMEM_VMEMMAP. Correct? Not arguing against replacement. Just wanting to refresh my memory. -- Mike Kravetz