lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Sun, 19 Sep 2010 11:35:33 -0700 (PDT) From: David Miller <davem@...emloft.net> To: therbert@...gle.com Cc: netdev@...r.kernel.org, sridharr@...gle.com Subject: Re: [RFC PATCH] xmit_compl_seq: information to reclaim vmsplice buffers From: Tom Herbert <therbert@...gle.com> Date: Thu, 16 Sep 2010 12:09:08 -0700 > We return the seq # as part of receive message since: 1) the socket is > already being accessed in the recvmsg, so tacking on this data should be > cheap 2) the recvmsg may often coincide with an acknowledgment that would > allow buffers to be reclaimed (esp. in response of a client request) 3) this > could also be achieved by another system call after recvmsg, but then we're > adding the cost of the system call. > > The recvmsg and sockopt return the sequence number of first unacknowleged > data, as opposed to the number of bytes outstanding. The sequence number is > not a relative value for our purposes, but the other is. Given just the > number of bytes outstanding, we would also need the # bytes that have ever > been written by application at that instant to compute the completed byte > number for reclaiming buffers-- so we would need synchronization between > read and write path in the application (lock needed). Ok, I'm convinced, thanks for explaining. Please address the other feedback you've received (if any) and formally submit this for inclusion into net-next-2.6 Thanks. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists