| From b42ab8e1aca951dd06c113159491b3fd5cf06f2e Mon Sep 17 00:00:00 2001 |
| From: Haiqing Bai <Haiqing.Bai@windriver.com> |
| Date: Thu, 24 Oct 2019 09:39:04 +0800 |
| Subject: [PATCH] Add "listen" action for a tcp socket which does not call |
| 'listen' after 'bind' |
| |
| It is found that /usr/bin/unfsd customus 100% cpu after starting qemu with 'nfs' |
| option, and below lots of error messages shows when strace the process: |
| |
| poll([{fd=3, events=POLLIN|POLLPRI|POLLRDNORM|POLLRDBAND},{fd=4, events=POLLIN|POLLPRI|POLLRDNORM|POLLRDBAND}, |
| {fd=5, events=POLLIN|POLLPRI|POLLRDNORM|POLLRDBAND},{fd=6, events =POLLIN|POLLPRI|POLLRDNORM|POLLRDBAND}], |
| 4, 2000) = 2 ([{fd=4, revents=POLLHUP},{fd=6, revents=POLLHUP}]) |
| accept(4, 0x7ffd5e6dddc0, [128]) = -1 EINVAL (Invalid argument) |
| accept(6, 0x7ffd5e6dddc0, [128]) = -1 EINVAL (Invalid argument) |
| |
| % time seconds usecs/call calls errors syscall |
| ------ ----------- ----------- --------- --------- ---------------- |
| 70.87 0.005392 0 513886 513886 accept |
| 29.13 0.002216 0 256943 poll |
| 0.00 0.000000 0 4 read |
| |
| The root cause is that 'listen' is not called for the binded |
| socket. The depended libtipc does not call 'listen' if found |
| the incomming socket is binded, so 'accept' reports the error |
| in the 'for' loop and cpu consumed. |
| |
| Upstream-Status: Pending |
| |
| Signed-off-by: Haiqing Bai <Haiqing.Bai@windriver.com> |
| --- |
| daemon.c | 7 +++++++ |
| 1 file changed, 7 insertions(+) |
| |
| diff --git a/daemon.c b/daemon.c |
| index 028a181..4c85903 100644 |
| --- a/daemon.c |
| +++ b/daemon.c |
| @@ -814,6 +814,13 @@ static SVCXPRT *create_tcp_transport(unsigned int port) |
| fprintf(stderr, "Couldn't bind to tcp port %d\n", port); |
| exit(1); |
| } |
| + |
| + if (listen(sock, SOMAXCONN) < 0) { |
| + perror("listen"); |
| + fprintf(stderr, "Couldn't listen on the address \n"); |
| + close(sock); |
| + exit(1); |
| + } |
| } |
| |
| transp = svctcp_create(sock, 0, 0); |
| -- |
| 1.9.1 |
| |