From 12c773480a643f178a0e68c1469ea0a2332cd23d Mon Sep 17 00:00:00 2001 From: rpaulo Date: Sat, 21 Mar 2009 23:08:04 +0000 Subject: [PATCH] Finish merge of zerocopy bpf. --- contrib/libpcap/pcap-bpf.c | 156 ------------------------------------- 1 file changed, 156 deletions(-) diff --git a/contrib/libpcap/pcap-bpf.c b/contrib/libpcap/pcap-bpf.c index 5ffcb83202c..73ab4e1fe41 100644 --- a/contrib/libpcap/pcap-bpf.c +++ b/contrib/libpcap/pcap-bpf.c @@ -721,159 +721,6 @@ pcap_stats_bpf(pcap_t *p, struct pcap_stat *ps) return (0); } -#ifdef BIOCGETBUFMODE -/* - * Zero-copy BPF buffer routines to check for and acknowledge BPF data in - * shared memory buffers. - * - * pcap_next_zbuf_shm(): Check for a newly available shared memory buffer, - * and set up p->buffer and cc to reflect one if available. Notice that if - * there was no prior buffer, we select zbuf1 as this will be the first - * buffer filled for a fresh BPF session. - */ -static int -pcap_next_zbuf_shm(pcap_t *p, int *cc) -{ - struct bpf_zbuf_header *bzh; - - if (p->zbuffer == p->zbuf2 || p->zbuffer == NULL) { - bzh = (struct bpf_zbuf_header *)p->zbuf1; - if (bzh->bzh_user_gen != - atomic_load_acq_int(&bzh->bzh_kernel_gen)) { - p->bzh = bzh; - p->zbuffer = (u_char *)p->zbuf1; - p->buffer = p->zbuffer + sizeof(*bzh); - *cc = bzh->bzh_kernel_len; - return (1); - } - } else if (p->zbuffer == p->zbuf1) { - bzh = (struct bpf_zbuf_header *)p->zbuf2; - if (bzh->bzh_user_gen != - atomic_load_acq_int(&bzh->bzh_kernel_gen)) { - p->bzh = bzh; - p->zbuffer = (u_char *)p->zbuf2; - p->buffer = p->zbuffer + sizeof(*bzh); - *cc = bzh->bzh_kernel_len; - return (1); - } - } - *cc = 0; - return (0); -} - -/* - * pcap_next_zbuf() -- Similar to pcap_next_zbuf_shm(), except wait using - * select() for data or a timeout, and possibly force rotation of the buffer - * in the event we time out or are in immediate mode. Invoke the shared - * memory check before doing system calls in order to avoid doing avoidable - * work. - */ -static int -pcap_next_zbuf(pcap_t *p, int *cc) -{ - struct bpf_zbuf bz; - struct timeval tv; - struct timespec cur; - fd_set r_set; - int data, r; - int tmout, expire; - -#define TSTOMILLI(ts) (((ts)->tv_sec * 1000) + ((ts)->tv_nsec / 1000000)) - /* - * Start out by seeing whether anything is waiting by checking the - * next shared memory buffer for data. - */ - data = pcap_next_zbuf_shm(p, cc); - if (data) - return (data); - /* - * If a previous sleep was interrupted due to signal delivery, make - * sure that the timeout gets adjusted accordingly. This requires - * that we analyze when the timeout should be been expired, and - * subtract the current time from that. If after this operation, - * our timeout is less then or equal to zero, handle it like a - * regular timeout. - */ - tmout = p->to_ms; - if (tmout) - (void) clock_gettime(CLOCK_MONOTONIC, &cur); - if (p->interrupted && p->to_ms) { - expire = TSTOMILLI(&p->firstsel) + p->to_ms; - tmout = expire - TSTOMILLI(&cur); -#undef TSTOMILLI - if (tmout <= 0) { - p->interrupted = 0; - data = pcap_next_zbuf_shm(p, cc); - if (data) - return (data); - if (ioctl(p->fd, BIOCROTZBUF, &bz) < 0) { - (void) snprintf(p->errbuf, PCAP_ERRBUF_SIZE, - "BIOCROTZBUF: %s", strerror(errno)); - return (-1); - } - return (pcap_next_zbuf_shm(p, cc)); - } - } - /* - * No data in the buffer, so must use select() to wait for data or - * the next timeout. - */ - FD_ZERO(&r_set); - FD_SET(p->fd, &r_set); - if (tmout != 0) { - tv.tv_sec = tmout / 1000; - tv.tv_usec = (tmout * 1000) % 1000000; - } - r = select(p->fd + 1, &r_set, NULL, NULL, p->to_ms != 0 ? &tv : - NULL); - if (r < 0 && errno == EINTR) { - if (!p->interrupted && p->to_ms) { - p->interrupted = 1; - p->firstsel = cur; - } - return (0); - } else if (r < 0) { - (void) snprintf(p->errbuf, PCAP_ERRBUF_SIZE, - "select: %s", strerror(errno)); - return (-1); - } - p->interrupted = 0; - /* - * Check again for data, which may exist now that we've either been - * woken up as a result of data or timed out. Try the "there's data" - * case first since it doesn't require a system call. - */ - data = pcap_next_zbuf_shm(p, cc); - if (data) - return (data); - - /* - * Try forcing a buffer rotation to dislodge timed out or immediate - * data. - */ - if (ioctl(p->fd, BIOCROTZBUF, &bz) < 0) { - (void) snprintf(p->errbuf, PCAP_ERRBUF_SIZE, - "BIOCROTZBUF: %s", strerror(errno)); - return (-1); - } - return (pcap_next_zbuf_shm(p, cc)); -} - -/* - * Notify kernel that we are done with the buffer. We don't reset zbuffer so - * that we know which buffer to use next time around. - */ -static int -pcap_ack_zbuf(pcap_t *p) -{ - - atomic_store_rel_int(&p->bzh->bzh_user_gen, p->bzh->bzh_kernel_gen); - p->bzh = NULL; - p->buffer = NULL; - return (0); -} -#endif - static int pcap_read_bpf(pcap_t *p, int cnt, pcap_handler callback, u_char *user) { @@ -881,9 +728,6 @@ pcap_read_bpf(pcap_t *p, int cnt, pcap_handler callback, u_char *user) int n = 0; register u_char *bp, *ep; u_char *datap; -#ifdef BIOCSETBUFMODE - int i; -#endif #ifdef PCAP_FDDIPAD register int pad; #endif -- 2.45.0