On 12/29/21 7:32 AM, menglong8.dong@gmail.com wrote:
From: Menglong Dong <redacted>
Replace kfree_skb() with kfree_skb_with_reason() in tcp_v4_rcv().
Following drop reason are added:
SKB_DROP_REASON_NO_SOCK
SKB_DROP_REASON_BAD_PACKET
SKB_DROP_REASON_TCP_CSUM
After this patch, 'kfree_skb' event will print message like this:
$ TASK-PID CPU# ||||| TIMESTAMP FUNCTION
$ | | | ||||| | |
<idle>-0 [000] ..s1. 36.113438: kfree_skb: skbaddr=(____ptrval____) protocol=2048 location=(____ptrval____) reason: NO_SOCK
The reason of skb drop is printed too.
Signed-off-by: Menglong Dong <redacted>
---
include/linux/skbuff.h | 3 +++
include/trace/events/skb.h | 3 +++
net/ipv4/tcp_ipv4.c | 10 ++++++++--
your first patch set was targeting UDP and now you are starting with tcp?
quoted hunk ↗ jump to hunk
3 files changed, 14 insertions(+), 2 deletions(-)
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 3620b3ff2154..f85db6c035d1 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -313,6 +313,9 @@ struct sk_buff;
*/
enum skb_drop_reason {
SKB_DROP_REASON_NOT_SPECIFIED,
+ SKB_DROP_REASON_NO_SOCK,
SKB_DROP_REASON_NO_SOCKET
+ SKB_DROP_REASON_BAD_PACKET,
SKB_DROP_REASON_PKT_TOO_SMALL
User oriented messages, not code based.
quoted hunk ↗ jump to hunk
+ SKB_DROP_REASON_TCP_CSUM,
SKB_DROP_REASON_MAX,
};
diff --git a/include/trace/events/skb.h b/include/trace/events/skb.h
index cab1c08a30cd..b9ea6b4ed7ec 100644
--- a/include/trace/events/skb.h
+++ b/include/trace/events/skb.h
@@ -11,6 +11,9 @@
#define TRACE_SKB_DROP_REASON \
EM(SKB_DROP_REASON_NOT_SPECIFIED, NOT_SPECIFIED) \
+ EM(SKB_DROP_REASON_NO_SOCK, NO_SOCK) \
+ EM(SKB_DROP_REASON_BAD_PACKET, BAD_PACKET) \
+ EM(SKB_DROP_REASON_TCP_CSUM, TCP_CSUM) \
EMe(SKB_DROP_REASON_MAX, HAHA_MAX)
#undef EM
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index ac10e4cdd8d0..03dc4c79b84b 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1971,8 +1971,10 @@ int tcp_v4_rcv(struct sk_buff *skb)
const struct tcphdr *th;
bool refcounted;
struct sock *sk;
+ int drop_reason;
int ret;
+ drop_reason = 0;
drop_reason = SKB_DROP_REASON_NOT_SPECIFIED;