From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752556Ab0C0CSH (ORCPT ); Fri, 26 Mar 2010 22:18:07 -0400 Received: from mail-yw0-f172.google.com ([209.85.211.172]:49487 "EHLO mail-yw0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752022Ab0C0CSE (ORCPT ); Fri, 26 Mar 2010 22:18:04 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=RMmCxpr++TYC/9lUBziRPsO7pMgg76CTW52Ufr0omCLZxzxcLz0qvooy6Y02a9jXJc aEv12f0DWsWCGdf0QeZ/fUwQ6Q4MjF3vH2urZHQsqbrfz5WetqBpnmkUmuAOTvkSXGQt v2D0MQ4FnLlNr1ysrKY/OBI15GI/GRZfhXgoE= Date: Fri, 26 Mar 2010 21:18:03 -0500 From: Brandon L Black To: netdev@vger.kernel.org Cc: "David S. Miller" , Arnaldo Carvalho de Melo , Ulrich Drepper , linux-kernel@vger.kernel.org Subject: [PATCH v2] Add MSG_WAITFORONE flag to recvmmsg Message-ID: <20100327021803.GA10866@xpc.home> References: <20100326223530.GA11817@xpc.home> <1269643470.2256.17.camel@edumazet-laptop> <84621a61003261555q2c78f6a8o5b438113bed6bd2@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-08-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Brandon L Black Add new flag MSG_WAITFORONE for the recvmmsg() syscall. When this flag is specified for a blocking socket, recvmmsg() will only block until at least 1 packet is available. The default behavior is to block until all vlen packets are available. This flag has no effect on non-blocking sockets or when used in combination with MSG_DONTWAIT. Signed-off-by: Brandon L Black --- diff --git a/include/linux/socket.h b/include/linux/socket.h index 7b3aae2..354cc56 100644 --- a/include/linux/socket.h +++ b/include/linux/socket.h @@ -255,6 +255,7 @@ struct ucred { #define MSG_ERRQUEUE 0x2000 /* Fetch message from error queue */ #define MSG_NOSIGNAL 0x4000 /* Do not generate SIGPIPE */ #define MSG_MORE 0x8000 /* Sender will send more */ +#define MSG_WAITFORONE 0x10000 /* recvmmsg(): block until 1+ packets avail */ #define MSG_EOF MSG_FIN diff --git a/net/socket.c b/net/socket.c index 769c386..f55ffe9 100644 --- a/net/socket.c +++ b/net/socket.c @@ -2135,6 +2135,10 @@ int __sys_recvmmsg(int fd, struct mmsghdr __user *mmsg, unsigned int vlen, break; ++datagrams; + /* MSG_WAITFORONE turns on MSG_DONTWAIT after one packet */ + if (flags & MSG_WAITFORONE) + flags |= MSG_DONTWAIT; + if (timeout) { ktime_get_ts(timeout); *timeout = timespec_sub(end_time, *timeout);