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To: Johannes Weiner Cc: Kanchana P Sridhar , linux-kernel@vger.kernel.org, linux-mm@kvack.org, nphamcs@gmail.com, chengming.zhou@linux.dev, usamaarif642@gmail.com, shakeel.butt@linux.dev, ryan.roberts@arm.com, ying.huang@intel.com, 21cnbao@gmail.com, akpm@linux-foundation.org, nanhai.zou@intel.com, wajdi.k.feghali@intel.com, vinodh.gopal@intel.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 154A8140009 X-Stat-Signature: 5jjbkzgo8mdxdcgpbc9m79dtg4kde51c X-HE-Tag: 1727288289-723274 X-HE-Meta: U2FsdGVkX19R2ZpzX2tjodVW27WiacFGT/9+upEBfBwvB+XdYNX09EA1jAZNquz4qB59EKrpfu4v77ZJ/twzLz1V+fLT8/9uuwG0pfWcNPx9iwmxJkg6ENiKWshdST1RicTHSxq0i1fBp4WvpC6cAoqPCglfFjceO3eL7gaKc8osXiK30B4UTXVmobN7XYeSQR3MHZg9I5I8cavsO1hH9E1clgQLJjSVF6th2BGsaCYyIbmOT1W2NsFt33sYS1Ky6a9MzvQWVZRHYA+8vqC+/TamYk554WcDjqejKsbBmbUT5znf0xSwAmtzhAjOXtlr7RIexZO9Sx/CgU4Yxj3hZxnqqvmtW/1H44VQAsK5EtxXUuB8gNBi0FyFplAxioNYI0cF1oNMSiHvP/rSgrNArzDU5hyKrcwdR+pWMKwOM91S5RLc4FOca6D4lmjSGcSo4rsc+pH0ho8eDrsBhjo4aopigy7rb8fsEzIIEJlRbUFfCA8wYUwzOsBY5vMm0mHYTzeROOef6gq8/y/O0MZj2/H0dmc5hb66pBpoUUl0PGwXobrUKKfwiaF2MK9HD1j6XBbwNv3vhU1Z5wevsUjX3iYXJxTIiUYUCruxmLZRzXOUDEDkH8aTo1cO1lMPvgWQi1ozY4oANAze7RFguYXdHBZeAzTmcBIeMmSRL5M/76Et7LMyYw/2sq2baBQuJ3c9ZzywM/l1EZc5wYervtTwsFcbZ8gzy+EV7J/+4cVNYCrKFJZCW5FUon4sX3bE6D+9woPz32Ji8aohwf1dqoNjAtK2s7fRW+BsRrST/oFG3RFDt5hc17+0SQtp7ZtfPvP4JjIhR81UL8ai7R7kj7jwWZMvG+MB8nClAMeHCmNg896M7tNhx3o57cmdLfDIDRKTRJQ0rP+eEzrVFiosawsNhzfnMVlbLUL4Y8Nx46LNJ8Pwdm45kezkWKSpUdeIFysDU/crFWhtI5A+1/P4btk NmlXjb4+ IFPQoTC+ZeW+jzrwedNZ2Pu/+gCtEauimM5r29tQHkPgyaZf5rWA9WdFI2Qlzew78xONZCXx/1u110ASdKmiN1Jp0l8cl8jCdE3+kb7T7OtXKlsxrjrGYo3/T4Y8b9pTbsKDmiuf14sAu3nYaDz/yM2xeBz2b2B0eBQhiaztZ5mNDXV3GiXpduAY+h1XNMi3iwrKE8UWVv5XjMHdgNSbLiRX7RcB2umheRQMYZel/R4FdGKcviDpl3LrWJMHu3P/xE+1ZcZPx9z+y8P4= 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: List-Subscribe: List-Unsubscribe: On Wed, Sep 25, 2024 at 7:27=E2=80=AFAM Johannes Weiner wrote: > > On Mon, Sep 23, 2024 at 06:17:07PM -0700, Kanchana P Sridhar wrote: > > zswap_store() will now store mTHP and PMD-size THP folios by compressin= g > > The hugepage terminology throughout the patches is a bit convoluted. > > There is no real distinction in this code between PMD-size THPs and > sub-PMD-sized mTHPs e.g. In particular, I think "mTHP" made sense when > they were added, to distinguish them from conventional THPs. But using > this term going forward just causes confusion, IMO. > > We're going through a big effort in the codebase to call all of these > things simply "folios" - which stands for "one or more pages". If you > want to emphasize the "more than one page", the convention is to call > it a "large folio". (If you need to emphasize that it's PMD size - > which doesn't apply to these patches, but just for the record - the > convention is "pmd-mappable folio".) > > So what this patch set does is "support large folios in zswap". Agreed on all of this, except it should be "support large folios in zswap _stores". We don't really support loading large folios.