From a2e2725541fad72416326798c2d7fa4dafb7d337 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Mon, 12 Oct 2009 23:40:10 -0700 Subject: net: Introduce recvmmsg socket syscall MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Meaning receive multiple messages, reducing the number of syscalls and net stack entry/exit operations. Next patches will introduce mechanisms where protocols that want to optimize this operation will provide an unlocked_recvmsg operation. This takes into account comments made by: . Paul Moore: sock_recvmsg is called only for the first datagram, sock_recvmsg_nosec is used for the rest. . Caitlin Bestler: recvmmsg now has a struct timespec timeout, that works in the same fashion as the ppoll one. If the underlying protocol returns a datagram with MSG_OOB set, this will make recvmmsg return right away with as many datagrams (+ the OOB one) it has received so far. . Rémi Denis-Courmont & Steven Whitehouse: If we receive N < vlen datagrams and then recvmsg returns an error, recvmmsg will return the successfully received datagrams, store the error and return it in the next call. This paves the way for a subsequent optimization, sk_prot->unlocked_recvmsg, where we will be able to acquire the lock only at batch start and end, not at every underlying recvmsg call. Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller --- include/linux/syscalls.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/linux/syscalls.h') diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index a990ace1a83..714f063a3e6 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -25,6 +25,7 @@ struct linux_dirent64; struct list_head; struct msgbuf; struct msghdr; +struct mmsghdr; struct msqid_ds; struct new_utsname; struct nfsctl_arg; @@ -677,6 +678,9 @@ asmlinkage long sys_recv(int, void __user *, size_t, unsigned); asmlinkage long sys_recvfrom(int, void __user *, size_t, unsigned, struct sockaddr __user *, int __user *); asmlinkage long sys_recvmsg(int fd, struct msghdr __user *msg, unsigned flags); +asmlinkage long sys_recvmmsg(int fd, struct mmsghdr __user *msg, + unsigned int vlen, unsigned flags, + struct timespec __user *timeout); asmlinkage long sys_socket(int, int, int); asmlinkage long sys_socketpair(int, int, int, int __user *); asmlinkage long sys_socketcall(int call, unsigned long __user *args); -- cgit v1.2.3-70-g09d2