Re: [PATCH net-next] trace: tcp: Add tracepoint for tcp_cwnd_reduction()
From: Steven Rostedt <rostedt@goodmis.org>
Date: 2025-02-11 17:04:57
Also in:
lkml, netdev
Subsystem:
the rest · Maintainer:
Linus Torvalds
On Tue, 11 Feb 2025 16:19:54 +0100 Eric Dumazet [off-list ref] wrote:
I can give my +2 on this patch, although I have no way of testing it.
If you want to test this, apply the below patch, enable CONFIG_SAMPLE_TRACE_CUSTOM_EVENTS, and after you boot up, do the following: # modprobe trace_custom_sched # cd /sys/kernel/tracing # echo 1 > events/custom/tcp_cwnd_reduction_tp/enable [ do something to trigger it ] # cat trace -- Steve
diff --git a/samples/trace_events/trace_custom_sched.c b/samples/trace_events/trace_custom_sched.c
index dd409b704b35..35b3cfa6e91d 100644
--- a/samples/trace_events/trace_custom_sched.c
+++ b/samples/trace_events/trace_custom_sched.c@@ -16,6 +16,7 @@ * from the C file, and not in the custom header file. */ #include <trace/events/sched.h> +#include <trace/events/tcp.h> /* Declare CREATE_CUSTOM_TRACE_EVENTS before including custom header */ #define CREATE_CUSTOM_TRACE_EVENTS
@@ -37,6 +38,7 @@ */ static void fct(struct tracepoint *tp, void *priv) { + trace_custom_event_tcp_cwnd_reduction_tp_update(tp); trace_custom_event_sched_switch_update(tp); trace_custom_event_sched_waking_update(tp); }
diff --git a/samples/trace_events/trace_custom_sched.h b/samples/trace_events/trace_custom_sched.h
index 951388334a3f..339957d692c0 100644
--- a/samples/trace_events/trace_custom_sched.h
+++ b/samples/trace_events/trace_custom_sched.h@@ -74,6 +74,33 @@ TRACE_CUSTOM_EVENT(sched_waking, TP_printk("pid=%d prio=%d", __entry->pid, __entry->prio) ) + +struct sock; + +TRACE_CUSTOM_EVENT(tcp_cwnd_reduction_tp, + + TP_PROTO(const struct sock *sk, int newly_acked_sacked, + int newly_lost, int flag), + + TP_ARGS(sk, newly_acked_sacked, newly_lost, flag), + + TP_STRUCT__entry( + __field( unsigned long, sk ) + __field( int, ack ) + __field( int, lost ) + __field( int, flag ) + ), + + TP_fast_assign( + __entry->sk = (unsigned long)sk; + __entry->ack = newly_acked_sacked; + __entry->lost = newly_lost; + __entry->flag = flag; + ), + + TP_printk("sk=%lx ack=%d lost=%d flag=%d", __entry->sk, + __entry->ack, __entry->lost, __entry->flag) +) #endif /* * Just like the headers that create TRACE_EVENTs, the below must