From e371a13238c6e5ebc0949a987830d21162f4bbac Mon Sep 17 00:00:00 2001 From: Darren Tucker Date: Tue, 12 Jan 2010 19:43:12 +1100 Subject: - djm@cvs.openbsd.org 2010/01/12 00:58:25 [monitor_fdpass.c] avoid spinning when fd passing on nonblocking sockets by calling poll() in the EINTR/EAGAIN path, much like we do in atomicio; ok dtucker@ --- monitor_fdpass.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) (limited to 'monitor_fdpass.c') diff --git a/monitor_fdpass.c b/monitor_fdpass.c index 4b9a066b..56d3afdf 100644 --- a/monitor_fdpass.c +++ b/monitor_fdpass.c @@ -1,4 +1,4 @@ -/* $OpenBSD: monitor_fdpass.c,v 1.18 2008/11/30 11:59:26 dtucker Exp $ */ +/* $OpenBSD: monitor_fdpass.c,v 1.19 2010/01/12 00:58:25 djm Exp $ */ /* * Copyright 2001 Niels Provos * All rights reserved. @@ -34,6 +34,7 @@ #endif #include +#include #include #include @@ -55,6 +56,7 @@ mm_send_fd(int sock, int fd) struct iovec vec; char ch = '\0'; ssize_t n; + struct pollfd pfd; memset(&msg, 0, sizeof(msg)); #ifdef HAVE_ACCRIGHTS_IN_MSGHDR @@ -75,9 +77,13 @@ mm_send_fd(int sock, int fd) msg.msg_iov = &vec; msg.msg_iovlen = 1; - while ((n = sendmsg(sock, &msg, 0)) == -1 && (errno == EAGAIN || - errno == EINTR)) + pfd.fd = sock; + pfd.events = POLLOUT; + while ((n = sendmsg(sock, &msg, 0)) == -1 && + (errno == EAGAIN || errno == EINTR)) { debug3("%s: sendmsg(%d): %s", __func__, fd, strerror(errno)); + (void)poll(&pfd, 1, -1); + } if (n == -1) { error("%s: sendmsg(%d): %s", __func__, fd, strerror(errno)); @@ -112,6 +118,7 @@ mm_receive_fd(int sock) ssize_t n; char ch; int fd; + struct pollfd pfd; memset(&msg, 0, sizeof(msg)); vec.iov_base = &ch; @@ -126,9 +133,13 @@ mm_receive_fd(int sock) msg.msg_controllen = sizeof(cmsgbuf.buf); #endif - while ((n = recvmsg(sock, &msg, 0)) == -1 && (errno == EAGAIN || - errno == EINTR)) + pfd.fd = sock; + pfd.events = POLLIN; + while ((n = recvmsg(sock, &msg, 0)) == -1 && + (errno == EAGAIN || errno == EINTR)) { debug3("%s: recvmsg: %s", __func__, strerror(errno)); + (void)poll(&pfd, 1, -1); + } if (n == -1) { error("%s: recvmsg: %s", __func__, strerror(errno)); return -1; -- cgit v1.2.1