[TCP] tcp_probe: improvements for net-2.6.22
Change tcp_probe to use ktime (needed to add one export).
Add option to only get events when cwnd changes - from Doug Leith
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_probe.c b/net/ipv4/tcp_probe.c
index 61f406f2..3938d5d 100644
--- a/net/ipv4/tcp_probe.c
+++ b/net/ipv4/tcp_probe.c
@@ -26,6 +26,8 @@
#include <linux/proc_fs.h>
#include <linux/module.h>
#include <linux/kfifo.h>
+#include <linux/ktime.h>
+#include <linux/time.h>
#include <linux/vmalloc.h>
#include <net/tcp.h>
@@ -34,43 +36,45 @@
MODULE_DESCRIPTION("TCP cwnd snooper");
MODULE_LICENSE("GPL");
-static int port = 0;
+static int port __read_mostly = 0;
MODULE_PARM_DESC(port, "Port to match (0=all)");
module_param(port, int, 0);
-static int bufsize = 64*1024;
+static int bufsize __read_mostly = 64*1024;
MODULE_PARM_DESC(bufsize, "Log buffer size (default 64k)");
module_param(bufsize, int, 0);
+static int full __read_mostly;
+MODULE_PARM_DESC(full, "Full log (1=every ack packet received, 0=only cwnd changes)");
+module_param(full, int, 0);
+
static const char procname[] = "tcpprobe";
struct {
- struct kfifo *fifo;
- spinlock_t lock;
+ struct kfifo *fifo;
+ spinlock_t lock;
wait_queue_head_t wait;
- struct timeval tstart;
+ ktime_t start;
+ u32 lastcwnd;
} tcpw;
+/*
+ * Print to log with timestamps.
+ * FIXME: causes an extra copy
+ */
static void printl(const char *fmt, ...)
{
va_list args;
int len;
- struct timeval now;
+ struct timespec tv;
char tbuf[256];
va_start(args, fmt);
- do_gettimeofday(&now);
+ /* want monotonic time since start of tcp_probe */
+ tv = ktime_to_timespec(ktime_sub(ktime_get(), tcpw.start));
- now.tv_sec -= tcpw.tstart.tv_sec;
- now.tv_usec -= tcpw.tstart.tv_usec;
- if (now.tv_usec < 0) {
- --now.tv_sec;
- now.tv_usec += 1000000;
- }
-
- len = sprintf(tbuf, "%lu.%06lu ",
- (unsigned long) now.tv_sec,
- (unsigned long) now.tv_usec);
+ len = sprintf(tbuf, "%lu.%09lu ",
+ (unsigned long) tv.tv_sec, (unsigned long) tv.tv_nsec);
len += vscnprintf(tbuf+len, sizeof(tbuf)-len, fmt, args);
va_end(args);
@@ -78,38 +82,44 @@
wake_up(&tcpw.wait);
}
-static int jtcp_sendmsg(struct kiocb *iocb, struct sock *sk,
- struct msghdr *msg, size_t size)
+/*
+ * Hook inserted to be called before each receive packet.
+ * Note: arguments must match tcp_rcv_established()!
+ */
+static int jtcp_rcv_established(struct sock *sk, struct sk_buff *skb,
+ struct tcphdr *th, unsigned len)
{
const struct tcp_sock *tp = tcp_sk(sk);
const struct inet_sock *inet = inet_sk(sk);
- if (port == 0 || ntohs(inet->dport) == port ||
- ntohs(inet->sport) == port) {
+ /* Only update if port matches */
+ if ((port == 0 || ntohs(inet->dport) == port || ntohs(inet->sport) == port)
+ && (full || tp->snd_cwnd != tcpw.lastcwnd)) {
printl("%d.%d.%d.%d:%u %d.%d.%d.%d:%u %d %#x %#x %u %u %u\n",
NIPQUAD(inet->saddr), ntohs(inet->sport),
NIPQUAD(inet->daddr), ntohs(inet->dport),
- size, tp->snd_nxt, tp->snd_una,
+ skb->len, tp->snd_nxt, tp->snd_una,
tp->snd_cwnd, tcp_current_ssthresh(sk),
- tp->snd_wnd);
+ tp->snd_wnd, tp->srtt >> 3);
+ tcpw.lastcwnd = tp->snd_cwnd;
}
jprobe_return();
return 0;
}
-static struct jprobe tcp_send_probe = {
+static struct jprobe tcp_probe = {
.kp = {
- .symbol_name = "tcp_sendmsg",
+ .symbol_name = "tcp_rcv_established",
},
- .entry = JPROBE_ENTRY(jtcp_sendmsg),
+ .entry = JPROBE_ENTRY(jtcp_rcv_established),
};
static int tcpprobe_open(struct inode * inode, struct file * file)
{
kfifo_reset(tcpw.fifo);
- do_gettimeofday(&tcpw.tstart);
+ tcpw.start = ktime_get();
return 0;
}
@@ -162,7 +172,7 @@
if (!proc_net_fops_create(procname, S_IRUSR, &tcpprobe_fops))
goto err0;
- ret = register_jprobe(&tcp_send_probe);
+ ret = register_jprobe(&tcp_probe);
if (ret)
goto err1;
@@ -180,7 +190,7 @@
{
kfifo_free(tcpw.fifo);
proc_net_remove(procname);
- unregister_jprobe(&tcp_send_probe);
+ unregister_jprobe(&tcp_probe);
}
module_exit(tcpprobe_exit);