From f0cc1b951c771c55d13ad7ebe0a2f4a4ab42c662 Mon Sep 17 00:00:00 2001
From: Antoine Tenart <atenart@redhat.com>
Date: Mon, 3 Jun 2024 16:26:41 +0200
Subject: [PATCH] tree: add common md event

Signed-off-by: Antoine Tenart <atenart@redhat.com>
---
 retis-events/src/common.rs     | 11 +++++++++++
 retis-events/src/events.rs     | 14 +++++++++++---
 retis/src/collect/collector.rs | 12 +++++++++++-
 tests/test_ovs.py              |  5 +++--
 4 files changed, 36 insertions(+), 6 deletions(-)

diff --git a/retis-events/src/common.rs b/retis-events/src/common.rs
index b6ee4c7db..f12361e99 100644
--- a/retis-events/src/common.rs
+++ b/retis-events/src/common.rs
@@ -2,6 +2,17 @@ use std::fmt;
 
 use crate::{event_section, event_type, *};
 
+#[event_section("md_common")]
+pub struct CommonEventMd {
+    pub retis_version: String,
+}
+
+impl EventFmt for CommonEventMd {
+    fn event_fmt(&self, f: &mut fmt::Formatter, _: DisplayFormat) -> fmt::Result {
+        write!(f, "Retis version {}", self.retis_version)
+    }
+}
+
 #[event_type]
 #[derive(Default)]
 pub struct TaskEvent {
diff --git a/retis-events/src/events.rs b/retis-events/src/events.rs
index 06c5cbaca..1845ee082 100644
--- a/retis-events/src/events.rs
+++ b/retis-events/src/events.rs
@@ -189,8 +189,9 @@ pub enum SectionId {
     Ovs = 8,
     Nft = 9,
     Ct = 10,
+    MdCommon = 11,
     // TODO: use std::mem::variant_count once in stable.
-    _MAX = 11,
+    _MAX = 12,
 }
 
 impl FromStr for SectionId {
@@ -210,6 +211,7 @@ impl FromStr for SectionId {
             OvsEvent::SECTION_NAME => Ovs,
             NftEvent::SECTION_NAME => Nft,
             CtEvent::SECTION_NAME => Ct,
+            CommonEventMd::SECTION_NAME => MdCommon,
             x => bail!("Can't construct a SectionId from {}", x),
         })
     }
@@ -230,6 +232,7 @@ impl SectionId {
             8 => Ovs,
             9 => Nft,
             10 => Ct,
+            11 => MdCommon,
             x => bail!("Can't construct a SectionId from {}", x),
         })
     }
@@ -249,7 +252,8 @@ impl SectionId {
             Ovs => 8,
             Nft => 9,
             Ct => 10,
-            _MAX => 11,
+            MdCommon => 11,
+            _MAX => 12,
         }
     }
 
@@ -267,13 +271,14 @@ impl SectionId {
             Ovs => OvsEvent::SECTION_NAME,
             Nft => NftEvent::SECTION_NAME,
             Ct => CtEvent::SECTION_NAME,
+            MdCommon => CommonEventMd::SECTION_NAME,
             _MAX => "_max",
         }
     }
 
     /// Is the section a metadata one?
     pub fn is_metadata(&self) -> bool {
-        false
+        matches!(self, SectionId::MdCommon)
     }
 }
 
@@ -317,6 +322,9 @@ fn event_sections() -> Result<&'static EventSectionMap> {
         events.insert(CtEvent::SECTION_NAME.to_string(), |v| {
             Ok(Box::new(serde_json::from_value::<CtEvent>(v)?))
         });
+        events.insert(CommonEventMd::SECTION_NAME.to_string(), |v| {
+            Ok(Box::new(serde_json::from_value::<CommonEventMd>(v)?))
+        });
         Ok(events)
     })
 }
diff --git a/retis/src/collect/collector.rs b/retis/src/collect/collector.rs
index 7961a37ad..b5bd0ec71 100644
--- a/retis/src/collect/collector.rs
+++ b/retis/src/collect/collector.rs
@@ -21,7 +21,7 @@ use crate::{
         kernel::Symbol,
         probe::kernel::utils::parse_probe,
     },
-    events::Event,
+    events::*,
     process::display::*,
 };
 
@@ -202,6 +202,16 @@ impl Collectors {
             bail!("Retis needs to be run as root when --allow-system-changes is used");
         }
 
+        // Set common md event.
+        self.md_event.insert_section(
+            SectionId::MdCommon,
+            Box::new(CommonEventMd {
+                retis_version: option_env!("RELEASE_VERSION")
+                    .unwrap_or("unspec")
+                    .to_string(),
+            }),
+        )?;
+
         // Try initializing all collectors.
         for name in &collect.args()?.collectors {
             let id = SectionId::from_str(name)?;
diff --git a/tests/test_ovs.py b/tests/test_ovs.py
index d2fe1ddce..5c445b74f 100644
--- a/tests/test_ovs.py
+++ b/tests/test_ovs.py
@@ -368,9 +368,10 @@ def test_ovs_tracking(two_port_ovs):
     series = retis.sort()
     # All events from the same direction must belong to the same packet (same
     # global tracking id).
-    assert len(series) == 2
-    assert len(series[0]) == len(expected_events) / 2
+    # 2 series + the initial md.
+    assert len(series) == 3
     assert len(series[1]) == len(expected_events) / 2
+    assert len(series[2]) == len(expected_events) / 2
 
 
 @pytest.mark.ovs_track