[sr-dev] git:sr_3.0: tcp: more consistent IO_FD_CLOSING usage

Module: sip-router Branch: sr_3.0 Commit: 38f371deaaa3abb26c64dce008b539015713f9d3 URL: http://git.sip-router.org/cgi-bin/gitweb.cgi/sip-router/?a=commit;h=38f371d… Author: Andrei Pelinescu-Onciul &lt;andrei(a)iptel.org&gt; Committer: Andrei Pelinescu-Onciul &lt;andrei(a)iptel.org&gt; Date: Sat Jun 19 00:21:58 2010 +0200 tcp: more consistent IO_FD_CLOSING usage - extra safety checks before using IO_FD_CLOSING in io_watch_del() calls (must be used only when the fd will be close() imediately afterwards). - add IO_FD_CLOSING when POLLERR or POLLHUP is detected in tcp_main and the socket receive buffer is empty (in this case the fd will be shortly closed) (cherry picked from commit 504ef98ed34366303476032013c28a4a7d1c8131) --- tcp_main.c | 79 ++++++++++++++++++++++++++++++++++++++++++++--------------- 1 files changed, 59 insertions(+), 20 deletions(-) diff --git a/tcp_main.c b/tcp_main.c index 54334ab..255753d 100644 --- a/tcp_main.c +++ b/tcp_main.c @@ -2889,18 +2889,31 @@ inline static int handle_tcp_child(struct tcp_child* tcp_c, int fd_i) case CONN_RELEASE: tcp_c->busy--; if (unlikely(tcpconn_put(tcpconn))){ + /* if refcnt was 1 => it was used only in the + tcp reader => it's not hashed or watched for IO + anymore => no need to io_watch_del() */ tcpconn_destroy(tcpconn); break; } if (unlikely(tcpconn->state==S_CONN_BAD)){ + if (tcpconn_try_unhash(tcpconn)) { #ifdef TCP_ASYNC - if (unlikely(tcpconn->flags & F_CONN_WRITE_W)){ - io_watch_del(&io_h, tcpconn->s, -1, IO_FD_CLOSING); + if (unlikely(tcpconn->flags & F_CONN_WRITE_W)){ + io_watch_del(&io_h, tcpconn->s, -1, IO_FD_CLOSING); + tcpconn->flags &= ~F_CONN_WRITE_W; + } +#endif /* TCP_ASYNC */ + tcpconn_put_destroy(tcpconn); + } +#ifdef TCP_ASYNC + else if (unlikely(tcpconn->flags & F_CONN_WRITE_W)){ + /* should never happen: if it's already unhashed, it + should not be watched for IO */ + BUG("unhashed connection watched for write\n"); + io_watch_del(&io_h, tcpconn->s, -1, 0); tcpconn->flags &= ~F_CONN_WRITE_W; } #endif /* TCP_ASYNC */ - if (tcpconn_try_unhash(tcpconn)) - tcpconn_put_destroy(tcpconn); break; } /* update the timeout*/ @@ -2937,12 +2950,17 @@ inline static int handle_tcp_child(struct tcp_child* tcp_c, int fd_i) TCP_EV_SEND_TIMEOUT(0, &tcpconn->rcv); TCP_STATS_SEND_TIMEOUT(); } - if (unlikely(tcpconn->flags & F_CONN_WRITE_W)){ - io_watch_del(&io_h, tcpconn->s, -1, IO_FD_CLOSING); + if (tcpconn_try_unhash(tcpconn)) { + if (unlikely(tcpconn->flags & F_CONN_WRITE_W)){ + io_watch_del(&io_h, tcpconn->s, -1, IO_FD_CLOSING); + tcpconn->flags&=~F_CONN_WRITE_W; + } + tcpconn_put_destroy(tcpconn); + } else if (unlikely(tcpconn->flags & F_CONN_WRITE_W)){ + BUG("unhashed connection watched for write\n"); + io_watch_del(&io_h, tcpconn->s, -1, 0); tcpconn->flags&=~F_CONN_WRITE_W; } - if (tcpconn_try_unhash(tcpconn)) - tcpconn_put_destroy(tcpconn); break; }else{ crt_timeout=MIN_unsigned(con_lifetime, @@ -2967,14 +2985,22 @@ inline static int handle_tcp_child(struct tcp_child* tcp_c, int fd_i) LOG(L_CRIT, "ERROR: tcp_main: handle_tcp_child: failed to add" " new socket to the fd list\n"); tcpconn->flags&=~F_CONN_READ_W; + if (tcpconn_try_unhash(tcpconn)) { #ifdef TCP_ASYNC - if (unlikely(tcpconn->flags & F_CONN_WRITE_W)){ - io_watch_del(&io_h, tcpconn->s, -1, IO_FD_CLOSING); + if (unlikely(tcpconn->flags & F_CONN_WRITE_W)){ + io_watch_del(&io_h, tcpconn->s, -1, IO_FD_CLOSING); + tcpconn->flags&=~F_CONN_WRITE_W; + } +#endif /* TCP_ASYNC */ + tcpconn_put_destroy(tcpconn); + } +#ifdef TCP_ASYNC + else if (unlikely(tcpconn->flags & F_CONN_WRITE_W)) { + BUG("unhashed connection watched for write\n"); + io_watch_del(&io_h, tcpconn->s, -1, 0); tcpconn->flags&=~F_CONN_WRITE_W; } #endif /* TCP_ASYNC */ - if (tcpconn_try_unhash(tcpconn)) - tcpconn_put_destroy(tcpconn); break; } DBG("handle_tcp_child: CONN_RELEASE %p refcnt= %d\n", @@ -3240,10 +3266,16 @@ inline static int handle_ser_child(struct process_table* p, int fd_i) POLLIN|POLLOUT, -1)<0)){ LOG(L_CRIT, "ERROR: tcp_main: handle_ser_child:" " failed to change socket watch events\n"); - io_watch_del(&io_h, tcpconn->s, -1, IO_FD_CLOSING); - tcpconn->flags&=~F_CONN_READ_W; - if (tcpconn_try_unhash(tcpconn)) + if (tcpconn_try_unhash(tcpconn)) { + io_watch_del(&io_h, tcpconn->s, -1, + IO_FD_CLOSING); + tcpconn->flags&=~F_CONN_READ_W; tcpconn_put_destroy(tcpconn); + } else { + BUG("unhashed connection watched for IO\n"); + io_watch_del(&io_h, tcpconn->s, -1, 0); + tcpconn->flags&=~F_CONN_READ_W; + } break; } } @@ -3573,10 +3605,6 @@ inline static int handle_tcpconn_ev(struct tcp_connection* tcpconn, short ev, (wbufq_run(tcpconn->s, tcpconn, &empty_q)<0) || (empty_q && tcpconn_close_after_send(tcpconn)) )){ - if (unlikely(io_watch_del(&io_h, tcpconn->s, fd_i, 0)<0)){ - LOG(L_ERR, "ERROR: handle_tcpconn_ev: io_watch_del(1) failed:" - " for %p, fd %d\n", tcpconn, tcpconn->s); - } if ((tcpconn->flags & F_CONN_READ_W) && (ev & POLLIN)){ /* connection is watched for read and there is a read event * (unfortunately if we have POLLIN here we don't know if @@ -3589,6 +3617,11 @@ inline static int handle_tcpconn_ev(struct tcp_connection* tcpconn, short ev, * conn. to a a child only if needed (another syscall + at * least 2 * syscalls in the reader + ...) */ if ((ioctl(tcpconn->s, FIONREAD, &bytes)>=0) && (bytes>0)){ + if (unlikely(io_watch_del(&io_h, tcpconn->s, fd_i, 0)<0)){ + LOG(L_ERR, "ERROR: handle_tcpconn_ev: io_watch_del(1)" + " failed: for %p, fd %d\n", + tcpconn, tcpconn->s); + } tcpconn->flags&=~(F_CONN_WRITE_W|F_CONN_READ_W| F_CONN_WANTS_RD|F_CONN_WANTS_WR); tcpconn->flags|=F_CONN_FORCE_EOF|F_CONN_WR_ERROR; @@ -3596,6 +3629,11 @@ inline static int handle_tcpconn_ev(struct tcp_connection* tcpconn, short ev, } /* if bytes==0 or ioctl failed, destroy the connection now */ } + if (unlikely(io_watch_del(&io_h, tcpconn->s, fd_i, + IO_FD_CLOSING) < 0)){ + LOG(L_ERR, "ERROR: handle_tcpconn_ev: io_watch_del() failed:" + " for %p, fd %d\n", tcpconn, tcpconn->s); + } tcpconn->flags&=~(F_CONN_WRITE_W|F_CONN_READ_W| F_CONN_WANTS_RD|F_CONN_WANTS_WR); if (unlikely(ev & POLLERR)){ @@ -3688,7 +3726,8 @@ send_to_child: tcpconn->flags&=~F_CONN_READER; #ifdef TCP_ASYNC if (tcpconn->flags & F_CONN_WRITE_W){ - if (unlikely(io_watch_del(&io_h, tcpconn->s, fd_i, 0)<0)){ + if (unlikely(io_watch_del(&io_h, tcpconn->s, fd_i, + IO_FD_CLOSING) < 0)){ LOG(L_ERR, "ERROR: handle_tcpconn_ev: io_watch_del(4)" " failed:" " for %p, fd %d\n", tcpconn, tcpconn->s);