Author: jtl Date: Wed Jul 6 16:17:13 2016 New Revision: 302374 URL: https://svnweb.freebsd.org/changeset/base/302374
Log: The TCPPCAP debugging feature caches recently-used mbufs for use in debugging TCP connections. This commit provides a mechanism to free those mbufs when the system is under memory pressure. Because this will result in lost debugging information, the behavior is controllable by a sysctl. The default setting is to free the mbufs. Reviewed by: gnn Approved by: re (gjb) Differential Revision: https://reviews.freebsd.org/D6931 Input from: novice_techie.com Modified: head/sys/netinet/tcp_pcap.c head/sys/netinet/tcp_pcap.h head/sys/netinet/tcp_subr.c Modified: head/sys/netinet/tcp_pcap.c ============================================================================== --- head/sys/netinet/tcp_pcap.c Wed Jul 6 16:02:15 2016 (r302373) +++ head/sys/netinet/tcp_pcap.c Wed Jul 6 16:17:13 2016 (r302374) @@ -42,9 +42,13 @@ #define M_LEADINGSPACE_NOWRITE(m) \ ((m)->m_data - M_START(m)) +int tcp_pcap_aggressive_free = 1; static int tcp_pcap_clusters_referenced_cur = 0; static int tcp_pcap_clusters_referenced_max = 0; +SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcp_pcap_aggressive_free, + CTLFLAG_RW, &tcp_pcap_aggressive_free, 0, + "Free saved packets when the memory system comes under pressure"); SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcp_pcap_clusters_referenced_cur, CTLFLAG_RD, &tcp_pcap_clusters_referenced_cur, 0, "Number of clusters currently referenced on TCP PCAP queues"); Modified: head/sys/netinet/tcp_pcap.h ============================================================================== --- head/sys/netinet/tcp_pcap.h Wed Jul 6 16:02:15 2016 (r302373) +++ head/sys/netinet/tcp_pcap.h Wed Jul 6 16:17:13 2016 (r302374) @@ -36,4 +36,6 @@ void tcp_pcap_tcpcb_init(struct tcpcb *t void tcp_pcap_set_sock_max(struct mbufq *queue, int newval); int tcp_pcap_get_sock_max(struct mbufq *queue); +extern int tcp_pcap_aggressive_free; + #endif /* _NETINET_TCP_PCAP_H_ */ Modified: head/sys/netinet/tcp_subr.c ============================================================================== --- head/sys/netinet/tcp_subr.c Wed Jul 6 16:02:15 2016 (r302373) +++ head/sys/netinet/tcp_subr.c Wed Jul 6 16:17:13 2016 (r302374) @@ -1605,6 +1605,13 @@ tcp_drain(void) if ((tcpb = intotcpcb(inpb)) != NULL) { tcp_reass_flush(tcpb); tcp_clean_sackreport(tcpb); +#ifdef TCPPCAP + if (tcp_pcap_aggressive_free) { + /* Free the TCP PCAP queues. */ + tcp_pcap_drain(&(tcpb->t_inpkts)); + tcp_pcap_drain(&(tcpb->t_outpkts)); + } +#endif } INP_WUNLOCK(inpb); } _______________________________________________ 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"
