From 093b0f366567aa3fed85c316f832607069202b23 Mon Sep 17 00:00:00 2001 From: Adrian Moreno Date: Thu, 4 Jul 2024 10:56:52 +0200 Subject: net: psample: add user cookie Add a user cookie to the sample metadata so that sample emitters can provide more contextual information to samples. If present, send the user cookie in a new attribute: PSAMPLE_ATTR_USER_COOKIE. Reviewed-by: Michal Kubiak Acked-by: Eelco Chaudron Reviewed-by: Simon Horman Reviewed-by: Ido Schimmel Signed-off-by: Adrian Moreno Link: https://patch.msgid.link/20240704085710.353845-2-amorenoz@redhat.com Signed-off-by: Jakub Kicinski --- include/uapi/linux/psample.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/uapi/linux/psample.h') diff --git a/include/uapi/linux/psample.h b/include/uapi/linux/psample.h index e585db5bf2d2..e80637e1d97b 100644 --- a/include/uapi/linux/psample.h +++ b/include/uapi/linux/psample.h @@ -19,6 +19,7 @@ enum { PSAMPLE_ATTR_LATENCY, /* u64, nanoseconds */ PSAMPLE_ATTR_TIMESTAMP, /* u64, nanoseconds */ PSAMPLE_ATTR_PROTO, /* u16 */ + PSAMPLE_ATTR_USER_COOKIE, /* binary, user provided data */ __PSAMPLE_ATTR_MAX }; -- cgit v1.2.3 From 7b1b2b60c63f070e0dfbe072ccaae13168b38d01 Mon Sep 17 00:00:00 2001 From: Adrian Moreno Date: Thu, 4 Jul 2024 10:56:55 +0200 Subject: net: psample: allow using rate as probability Although not explicitly documented in the psample module itself, the definition of PSAMPLE_ATTR_SAMPLE_RATE seems inherited from act_sample. Quoting tc-sample(8): "RATE of 100 will lead to an average of one sampled packet out of every 100 observed." With this semantics, the rates that we can express with an unsigned 32-bits number are very unevenly distributed and concentrated towards "sampling few packets". For example, we can express a probability of 2.32E-8% but we cannot express anything between 100% and 50%. For sampling applications that are capable of sampling a decent amount of packets, this sampling rate semantics is not very useful. Add a new flag to the uAPI that indicates that the sampling rate is expressed in scaled probability, this is: - 0 is 0% probability, no packets get sampled. - U32_MAX is 100% probability, all packets get sampled. Reviewed-by: Aaron Conole Acked-by: Eelco Chaudron Reviewed-by: Ido Schimmel Signed-off-by: Adrian Moreno Link: https://patch.msgid.link/20240704085710.353845-5-amorenoz@redhat.com Signed-off-by: Jakub Kicinski --- include/uapi/linux/psample.h | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'include/uapi/linux/psample.h') diff --git a/include/uapi/linux/psample.h b/include/uapi/linux/psample.h index e80637e1d97b..b765f0e81f20 100644 --- a/include/uapi/linux/psample.h +++ b/include/uapi/linux/psample.h @@ -8,7 +8,11 @@ enum { PSAMPLE_ATTR_ORIGSIZE, PSAMPLE_ATTR_SAMPLE_GROUP, PSAMPLE_ATTR_GROUP_SEQ, - PSAMPLE_ATTR_SAMPLE_RATE, + PSAMPLE_ATTR_SAMPLE_RATE, /* u32, ratio between observed and + * sampled packets or scaled probability + * if PSAMPLE_ATTR_SAMPLE_PROBABILITY + * is set. + */ PSAMPLE_ATTR_DATA, PSAMPLE_ATTR_GROUP_REFCOUNT, PSAMPLE_ATTR_TUNNEL, @@ -20,6 +24,10 @@ enum { PSAMPLE_ATTR_TIMESTAMP, /* u64, nanoseconds */ PSAMPLE_ATTR_PROTO, /* u16 */ PSAMPLE_ATTR_USER_COOKIE, /* binary, user provided data */ + PSAMPLE_ATTR_SAMPLE_PROBABILITY,/* no argument, interpret rate in + * PSAMPLE_ATTR_SAMPLE_RATE as a + * probability scaled 0 - U32_MAX. + */ __PSAMPLE_ATTR_MAX }; -- cgit v1.2.3