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Miller" , Jakub Kicinski , Paolo Abeni , Willem de Bruijn , Matthew Wilcox , Al Viro , Christoph Hellwig , Jens Axboe , Jeff Layton , Christian Brauner , Chuck Lever III , Linus Torvalds , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 2ADDB4001A X-Rspam-User: X-Stat-Signature: f4f3jcf9xxwpcujc5jiwm5ayrnb1jxij X-HE-Tag: 1680774414-298787 X-HE-Meta: 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 F3R3GLVr /kiLjV4fwQUd0JojC/+Bb02KP5cY3Q/ZKe5GbUrSXu6z6WttjycDnsw09wx92MRs1N97HYOkL0ZgAUQ7zPDPdUJr8N3rZ3txPl3vj7xfjGQJ02axRs9pMNRnxZOwHqwTL/Nekk6VGiWhvXRph04EWt/N1/pFla0GIB2DM0a1ZIKquYOZf+p1ULsabwO+Vh+amra0bZe+puZtY5+dlajSMXJwLCPcvTEjUIQFaXbpJyYKBreG29KpBhVjsEmcWuMQFSo+lyTGr0meEQExZtXGexwUGl1GIPB38Dc2kR80s8D7rFG+/o7JXJYS46JJHX1i5KCs++YIRcCBJ3ABkUcITbDlpToVlz/TFX+k5v8zWSBLLMyU7wQUD5+6maneHUAjqHBtg 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 Thu, Apr 6, 2023 at 11:42=E2=80=AFAM David Howells = wrote: > > Here's the first tranche of patches towards providing a MSG_SPLICE_PAGES > internal sendmsg flag that is intended to replace the ->sendpage() op wit= h > calls to sendmsg(). MSG_SPLICE is a hint that tells the protocol that it > should splice the pages supplied if it can and copy them if not. > I find this patch series quite big/risky for 6.4 Can you spell out why we need "unspliceable pages support" ? This seems to add quite a lot of code in fast paths. Thanks.