Author: jtl Date: Tue Apr 14 15:30:34 2020 New Revision: 359922 URL: https://svnweb.freebsd.org/changeset/base/359922
Log: Print more detail as part of the sonewconn() overflow message. When a socket's listen queue overflows, sonewconn() emits a debug-level log message. These messages are sometimes useful to systems administrators in highlighting a process which is not keeping up with its listen queue. This commit attempts to enhance the usefulness of this message by printing more details about the socket's address. If all else fails, it will at least print the domain name of the socket. Reviewed by: bz, jhb, kbowling MFC after: 2 weeks Sponsored by: Netflix, Inc. Differential Revision: https://reviews.freebsd.org/D24272 Modified: head/sys/kern/uipc_socket.c Modified: head/sys/kern/uipc_socket.c ============================================================================== --- head/sys/kern/uipc_socket.c Tue Apr 14 15:27:24 2020 (r359921) +++ head/sys/kern/uipc_socket.c Tue Apr 14 15:30:34 2020 (r359922) @@ -130,6 +130,7 @@ __FBSDID("$FreeBSD$"); #include <sys/poll.h> #include <sys/proc.h> #include <sys/protosw.h> +#include <sys/sbuf.h> #include <sys/socket.h> #include <sys/socketvar.h> #include <sys/resourcevar.h> @@ -140,9 +141,12 @@ __FBSDID("$FreeBSD$"); #include <sys/sysctl.h> #include <sys/taskqueue.h> #include <sys/uio.h> +#include <sys/un.h> +#include <sys/unpcb.h> #include <sys/jail.h> #include <sys/syslog.h> #include <netinet/in.h> +#include <netinet/in_pcb.h> #include <netinet/tcp.h> #include <net/vnet.h> @@ -587,8 +591,17 @@ sonewconn(struct socket *head, int connstatus) static struct timeval overinterval = { 60, 0 }; static int overcount; + struct sbuf descrsb; struct socket *so; u_int over; + int len; + const char localprefix[] = "local:"; + char descrbuf[SUNPATHLEN + sizeof(localprefix)]; +#if defined(INET6) + char addrbuf[INET6_ADDRSTRLEN]; +#elif defined(INET) + char addrbuf[INET_ADDRSTRLEN]; +#endif SOLISTEN_LOCK(head); over = (head->sol_qlen > 3 * head->sol_qlimit / 2); @@ -601,10 +614,80 @@ sonewconn(struct socket *head, int connstatus) overcount++; if (ratecheck(&lastover, &overinterval)) { - log(LOG_DEBUG, "%s: pcb %p: Listen queue overflow: " + /* + * Try to print something descriptive about the + * socket for the error message. + */ + sbuf_new(&descrsb, descrbuf, sizeof(descrbuf), + SBUF_FIXEDLEN); + switch (head->so_proto->pr_domain->dom_family) { +#if defined(INET) || defined(INET6) +#ifdef INET + case AF_INET: +#endif +#ifdef INET6 + case AF_INET6: + if (head->so_proto->pr_domain->dom_family == + AF_INET6 || + (sotoinpcb(head)->inp_inc.inc_flags & + INC_ISIPV6)) { + ip6_sprintf(addrbuf, + &sotoinpcb(head)->inp_inc.inc6_laddr); + sbuf_printf(&descrsb, "[%s]", addrbuf); + } else +#endif + { +#ifdef INET + inet_ntoa_r( + sotoinpcb(head)->inp_inc.inc_laddr, + addrbuf); + sbuf_cat(&descrsb, addrbuf); +#endif + } + sbuf_printf(&descrsb, ":%hu (proto %u)", + ntohs(sotoinpcb(head)->inp_inc.inc_lport), + head->so_proto->pr_protocol); + break; +#endif /* INET || INET6 */ + case AF_UNIX: + sbuf_cat(&descrsb, localprefix); + if (sotounpcb(head)->unp_addr != NULL) + len = + sotounpcb(head)->unp_addr->sun_len - + offsetof(struct sockaddr_un, + sun_path); + else + len = 0; + if (len > 0) + sbuf_bcat(&descrsb, + sotounpcb(head)->unp_addr->sun_path, + len); + else + sbuf_cat(&descrsb, "(unknown)"); + break; + } + + /* + * If we can't print something more specific, at least + * print the domain name. + */ + if (sbuf_finish(&descrsb) != 0 || + sbuf_len(&descrsb) <= 0) { + sbuf_clear(&descrsb); + sbuf_cat(&descrsb, + head->so_proto->pr_domain->dom_name ?: + "unknown"); + sbuf_finish(&descrsb); + } + KASSERT(sbuf_len(&descrsb) > 0, + ("%s: sbuf creation failed", __func__)); + log(LOG_DEBUG, + "%s: pcb %p (%s): Listen queue overflow: " "%i already in queue awaiting acceptance " "(%d occurrences)\n", - __func__, head->so_pcb, head->sol_qlen, overcount); + __func__, head->so_pcb, sbuf_data(&descrsb), + head->sol_qlen, overcount); + sbuf_delete(&descrsb); overcount = 0; } _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
