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See http://www.infradead.org/rpr.html X-Rspamd-Queue-Id: AD3CC40004 X-Stat-Signature: 9mbbxsfpe7951fwrtni5zy5jwc4zfzif X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1746600852-509665 X-HE-Meta: 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 gCcdrATC ZDDfG3wUHNb6pmqJHRyQ6VCldQbKm+tFkOiJcM/j7vdryGjqHY7/JFTtjZLVuv0/Q1Sz1JxwsFlfSOb2qGiyXLSdNPLxrXSrGQlgkpkzYl7GuSt3G3BX6B51K6MAdJ8t1oTMhqLcHYdZHdNoVDYB6qP6qNf/y19rK7V25tHmTP0UTdwXJq7FhEUt+mo9h1d6Dn5xbC3eFAFSW95WCi0qSqwBS/i2xS45f00BgPaEtX0TShyVNAvYUi6BtvQ32MMI8mizzFfLWysJNoILfk1K5LBXvx7obd9ULHhTOd7dCq6Cr0h8UXgXD9U/Y93p0AgHPJcNPq8s0FDTrMPfQLr7VwJPz8PpEJn2Xiaj8z4RuY6KP+QJqKkzzHT1BH8HS6tNdAQPzFTBI6MhM0VOlx3sg+rp7Us6Z0DA0zPHjrQ9YlXMY/BNi0YJSBASwnPyvw7E4s6xEY+O7wCjkp99WAP6Hh/Yoeu1NcmM6MsAY 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, May 07, 2025 at 03:08:08PM +0900, Sergey Senozhatsky wrote: > > This sounds interesting. We might get rid of lots of memcpy() > > in object read/write paths, and so on. I don't know if 0-order > > chaining was the only option for zsmalloc, or just happened to > > be the first one. > > I assume we might have problems with zspage release path. vfree() > should break .swap_slot_free_notify, as far as I can see. > .swap_slot_free_notify is called under swap-cluster spin-lock, > so if we free the last object in the zspage we cannot immediately > free that zspage, because vfree() might_sleep(). Note that swap_slot_free_notify really needs to go away in favor of just sending a discard bio. Having special block ops for a single user bypassing the proper block interface is not sustainable.