From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [PATCH v2] Add MSG_WAITFORONE flag to recvmmsg Date: Sat, 27 Mar 2010 07:00:04 +0100 Message-ID: <1269669604.2256.20.camel@edumazet-laptop> References: <20100326223530.GA11817@xpc.home> <1269643470.2256.17.camel@edumazet-laptop> <84621a61003261555q2c78f6a8o5b438113bed6bd2@mail.gmail.com> <20100327021803.GA10866@xpc.home> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: netdev@vger.kernel.org, "David S. Miller" , Arnaldo Carvalho de Melo , Ulrich Drepper , linux-kernel@vger.kernel.org To: Brandon L Black Return-path: In-Reply-To: <20100327021803.GA10866@xpc.home> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Le vendredi 26 mars 2010 =C3=A0 21:18 -0500, Brandon L Black a =C3=A9cr= it : > From: Brandon L Black >=20 > 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. >=20 > Signed-off-by: Brandon L Black >=20 Acked-by: Eric Dumazet > --- > 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 */ > =20 > #define MSG_EOF MSG_FIN > =20 > 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 __us= er *mmsg, unsigned int vlen, > break; > ++datagrams; > =20 > + /* MSG_WAITFORONE turns on MSG_DONTWAIT after one packet */ > + if (flags & MSG_WAITFORONE) > + flags |=3D MSG_DONTWAIT; > + > if (timeout) { > ktime_get_ts(timeout); > *timeout =3D timespec_sub(end_time, *timeout); > --