No functional changes here. I add skb_enable_app_tstamp() to test
if the orig_skb matches the usage of application SO_TIMESTAMPING
and skb_sw_tstamp_tx() to distinguish the software and hardware
timestamp when tsflag is SCM_TSTAMP_SND.
Also, I deliberately distinguish the the software and hardware
SCM_TSTAMP_SND timestamp by passing 'sw' parameter in order to
avoid such a case where hardware may go wrong and pass a NULL
hwstamps, which is even though unlikely to happen. If it really
happens, bpf prog will finally consider it as a software timestamp.
It will be hardly recognized. Let's make the timestamping part
more robust.
After this patch, I will soon add checks about bpf SO_TIMESTAMPING.
In this way, we can support two modes parallelly.
Signed-off-by: Jason Xing <kerneljasonxing@xxxxxxxxx>
---
include/linux/skbuff.h | 13 +++++++------
net/core/dev.c | 2 +-
net/core/skbuff.c | 32 ++++++++++++++++++++++++++++++--
net/ipv4/tcp_input.c | 3 ++-
4 files changed, 40 insertions(+), 10 deletions(-)
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index bb2b751d274a..dfc419281cc9 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -39,6 +39,7 @@
#include <net/net_debug.h>
#include <net/dropreason-core.h>
#include <net/netmem.h>
+#include <uapi/linux/errqueue.h>
/**
* DOC: skb checksums
@@ -4533,18 +4534,18 @@ void skb_complete_tx_timestamp(struct sk_buff *skb,
void __skb_tstamp_tx(struct sk_buff *orig_skb, const struct sk_buff *ack_skb,
struct skb_shared_hwtstamps *hwtstamps,
- struct sock *sk, int tstype);
+ struct sock *sk, bool sw, int tstype);
/**
- * skb_tstamp_tx - queue clone of skb with send time stamps
+ * skb_tstamp_tx - queue clone of skb with send HARDWARE timestamps
* @orig_skb: the original outgoing packet
* @hwtstamps: hardware time stamps, may be NULL if not available
*
* If the skb has a socket associated, then this function clones the
* skb (thus sharing the actual data and optional structures), stores
- * the optional hardware time stamping information (if non NULL) or
- * generates a software time stamp (otherwise), then queues the clone
- * to the error queue of the socket. Errors are silently ignored.
+ * the optional hardware time stamping information (if non NULL) then
+ * queues the clone to the error queue of the socket. Errors are
+ * silently ignored.
*/
void skb_tstamp_tx(struct sk_buff *orig_skb,
struct skb_shared_hwtstamps *hwtstamps);
@@ -4565,7 +4566,7 @@ static inline void skb_tx_timestamp(struct sk_buff *skb)
{
skb_clone_tx_timestamp(skb);
if (skb_shinfo(skb)->tx_flags & SKBTX_SW_TSTAMP)
- skb_tstamp_tx(skb, NULL);
+ __skb_tstamp_tx(skb, NULL, NULL, skb->sk, true, SCM_TSTAMP_SND);
}
/**
diff --git a/net/core/dev.c b/net/core/dev.c
index afa2282f2604..d77b8389753e 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4501,7 +4501,7 @@ int __dev_queue_xmit(struct sk_buff *skb, struct net_device *sb_dev)
skb_assert_len(skb);
if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP))
- __skb_tstamp_tx(skb, NULL, NULL, skb->sk, SCM_TSTAMP_SCHED);
+ __skb_tstamp_tx(skb, NULL, NULL, skb->sk, true, SCM_TSTAMP_SCHED);
/* Disable soft irqs for various locks below. Also
* stops preemption for RCU.
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index a441613a1e6c..6042961dfc02 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -5539,10 +5539,35 @@ void skb_complete_tx_timestamp(struct sk_buff *skb,
}
EXPORT_SYMBOL_GPL(skb_complete_tx_timestamp);
+static bool skb_enable_app_tstamp(struct sk_buff *skb, int tstype, bool sw)
+{
+ int flag;
+
+ switch (tstype) {
+ case SCM_TSTAMP_SCHED:
+ flag = SKBTX_SCHED_TSTAMP;
+ break;
+ case SCM_TSTAMP_SND:
+ flag = sw ? SKBTX_SW_TSTAMP : SKBTX_HW_TSTAMP;
+ break;
+ case SCM_TSTAMP_ACK:
+ if (TCP_SKB_CB(skb)->txstamp_ack)
+ return true;
+ fallthrough;
+ default:
+ return false;
+ }
+
+ if (skb_shinfo(skb)->tx_flags & flag)
+ return true;
+
+ return false;
+}
+
void __skb_tstamp_tx(struct sk_buff *orig_skb,
const struct sk_buff *ack_skb,
struct skb_shared_hwtstamps *hwtstamps,
- struct sock *sk, int tstype)
+ struct sock *sk, bool sw, int tstype)
{
struct sk_buff *skb;
bool tsonly, opt_stats = false;
@@ -5551,6 +5576,9 @@ void __skb_tstamp_tx(struct sk_buff *orig_skb,
if (!sk)
return;
+ if (!skb_enable_app_tstamp(orig_skb, tstype, sw))
+ return;
+
tsflags = READ_ONCE(sk->sk_tsflags);
if (!hwtstamps && !(tsflags & SOF_TIMESTAMPING_OPT_TX_SWHW) &&
skb_shinfo(orig_skb)->tx_flags & SKBTX_IN_PROGRESS)
@@ -5599,7 +5627,7 @@ EXPORT_SYMBOL_GPL(__skb_tstamp_tx);
void skb_tstamp_tx(struct sk_buff *orig_skb,
struct skb_shared_hwtstamps *hwtstamps)
{
- return __skb_tstamp_tx(orig_skb, NULL, hwtstamps, orig_skb->sk,
+ return __skb_tstamp_tx(orig_skb, NULL, hwtstamps, orig_skb->sk, false,
SCM_TSTAMP_SND);
}
EXPORT_SYMBOL_GPL(skb_tstamp_tx);
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 77185479ed5e..62252702929d 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -3330,7 +3330,8 @@ static void tcp_ack_tstamp(struct sock *sk, struct sk_buff *skb,
if (!before(shinfo->tskey, prior_snd_una) &&
before(shinfo->tskey, tcp_sk(sk)->snd_una)) {
tcp_skb_tsorted_save(skb) {
- __skb_tstamp_tx(skb, ack_skb, NULL, sk, SCM_TSTAMP_ACK);
+ __skb_tstamp_tx(skb, ack_skb, NULL, sk, true,
+ SCM_TSTAMP_ACK);
} tcp_skb_tsorted_restore(skb);
}
}
--
2.43.5
