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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.54.1 (3.54.1-1.fc41) MIME-Version: 1.0 X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 1B91118000C X-Stat-Signature: dqnt8a4rhfec51xhxwisjek3q37sr758 X-Rspam-User: X-HE-Tag: 1737395844-835749 X-HE-Meta: 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 vr2XrPdo pf5ejhOIvp28F3qX4EG6/SJVA+dJ8AnrddXQ6CpFIMo9d7drdYP6KA87KgQKhRvKQ6dhjVVE8Ctz84RAoN3Te39WvJpktGJcUv7dX+3jxgSWhip8FovoiuAPF520J1jSuOOSmaUit7gfTDrgSgtArONeCXVbszL6oZgXzTz/ZEQF8yK/5xqkpqGMj3h16x/WgFtch6R+NG8cM80sxvmOoXOXaxKbogRe5Pub83f7xi+XERM3aITzsff9r0MU6+FdJ0bf1semkTCFnLtWDvgBB+1l9Ogjju3XlQoONadzFWr2aU3Y+c/2wShjmAKvIPAu15ZN4LeFMkLiPDwliRQFvk4bYNXF0qrDkoyuLsQpPhzIF7fKwbQfFtggzN+3ZWcTy25z4HpVpbVG06bM= 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 Mon, 2025-01-20 at 19:50 +0200, Nadav Amit wrote: > [ Thanks for your patience. ] >=20 > > On 20 Jan 2025, at 19:11, Rik van Riel wrote: > >=20 > > On Mon, 2025-01-20 at 19:09 +0200, Nadav Amit wrote: > >=20 > > This is the page reclaim code. > >=20 > > The process that has those other pages mapped might be > > running on other CPUs simultaneously with the page > > reclaim code. > >=20 > > Even if we were invalidating one of our own pages this > > way, there could be other threads in the same process, > > running while we are in the page reclaim code. >=20 >=20 >=20 > Of course, but there is nothing new here. Let me see where we lose > each other by first stating the goal, what you propose, and what I > suggest. >=20 > We are issuing invlpgb and we need to ensure tlbsync on the same core > that initiated invlpgb before arch_tlbbatch_flush() finishes. That=E2=80= =99s > all that matters for our discussion (correct me if I miss something). >=20 > You solved it by disabling migration and running tlbsync at the end. >=20 > I suggest *not* to disable migration, to keep running tlbsync at the > arch_tlbbatch_flush() as you do, and if context-switch happens after > arch_tlbbatch_add_pending() and before arch_tlbbatch_flush(), to run > tlbsync during the context switch. >=20 How would you keep track of CPUs where the tlbsync has NOT happened before arch_tlbbatch_flush()? That part seems to be missing still. --=20 All Rights Reversed.