From 5a07c0a055290fe95836a3a925a739105cbf940f Mon Sep 17 00:00:00 2001
From: Luc Varoqui <luc@varoqui.org>
Date: Thu, 1 Oct 2026 16:50:27 +0200
Subject: [PATCH 1/2] feat(instrument-hooks): declare benchmarks run in another
 process

Add set_executed_benchmark_for_pid, which passes an explicit pid to
instrument_hooks_set_executed_benchmark instead of the calling process'
own. set_executed_benchmark keeps its behavior and delegates to it.

Bump instrument-hooks, whose valgrind instrument now writes a
"Benchmark pid: <pid>" desc line in the dump part when that pid is not
the calling process'. This also brings thread-safe C API exports and the
callgrind_toggle_collect helper.

Refs COD-3722
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---
 .../instrument-hooks-bindings/instrument-hooks |  2 +-
 crates/instrument-hooks-bindings/src/lib.rs    | 18 ++++++++++++++++--
 2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/crates/instrument-hooks-bindings/instrument-hooks b/crates/instrument-hooks-bindings/instrument-hooks
index b9ddb5bc6..11c29ac43 160000
--- a/crates/instrument-hooks-bindings/instrument-hooks
+++ b/crates/instrument-hooks-bindings/instrument-hooks
@@ -1 +1 @@
-Subproject commit b9ddb5bc654b2e6fa13eb18efcd3a45e7ecda0bb
+Subproject commit 11c29ac432cc33d651c7e2bf76651f4312329095
diff --git a/crates/instrument-hooks-bindings/src/lib.rs b/crates/instrument-hooks-bindings/src/lib.rs
index 8ea620cb8..09a031dd7 100644
--- a/crates/instrument-hooks-bindings/src/lib.rs
+++ b/crates/instrument-hooks-bindings/src/lib.rs
@@ -58,10 +58,15 @@ mod linux_impl {
 
         #[inline(always)]
         pub fn set_executed_benchmark(&self, uri: &str) -> Result<(), u8> {
-            let pid = std::process::id() as i32;
+            self.set_executed_benchmark_for_pid(std::process::id(), uri)
+        }
+
+        /// Declares a benchmark that ran in the process `pid` rather than in this one.
+        #[inline(always)]
+        pub fn set_executed_benchmark_for_pid(&self, pid: u32, uri: &str) -> Result<(), u8> {
             let c_uri = CString::new(uri).map_err(|_| 1u8)?;
             let result = unsafe {
-                ffi::instrument_hooks_set_executed_benchmark(self.0, pid, c_uri.as_ptr())
+                ffi::instrument_hooks_set_executed_benchmark(self.0, pid as i32, c_uri.as_ptr())
             };
             if result == 0 { Ok(()) } else { Err(result) }
         }
@@ -184,6 +189,10 @@ mod other_impl {
             Ok(())
         }
 
+        pub fn set_executed_benchmark_for_pid(&self, _pid: u32, _uri: &str) -> Result<(), u8> {
+            Ok(())
+        }
+
         pub fn set_integration(&self, _name: &str, _version: &str) -> Result<(), u8> {
             Ok(())
         }
@@ -213,6 +222,11 @@ mod tests {
         let hooks = InstrumentHooks::instance("test_integration", "1.0.0");
         assert!(!hooks.is_instrumented() || hooks.start_benchmark().is_ok());
         assert!(hooks.set_executed_benchmark("test_uri").is_ok());
+        assert!(
+            hooks
+                .set_executed_benchmark_for_pid(std::process::id() + 1, "test_uri")
+                .is_ok()
+        );
         assert!(hooks.set_integration("test_integration", "1.0.0").is_ok());
         let start = InstrumentHooks::current_timestamp();
         let end = start + 1_000_000; // Simulate 1ms later

From 485598a32671af0f1ad5cc08b686ab9d5a4681ed Mon Sep 17 00:00:00 2001
From: Luc Varoqui <luc@varoqui.org>
Date: Thu, 1 Oct 2026 16:50:56 +0200
Subject: [PATCH 2/2] feat(exec-harness): declare the benchmarked command's pid

exec-harness measures a command from its own process, so the dumped
part also holds the harness's cost of spawning the command and waiting
for it, a fixed overhead added to every benchmark.

Spawn the command and pass its pid to set_executed_benchmark_for_pid,
so the profile states which process ran the benchmark and the harness's
own cost can be told apart. Under valgrind this needs a valgrind build
supporting CALLGRIND_REGISTER_DESC; older builds ignore it.

Closes COD-3722
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---
 crates/exec-harness/src/analysis/mod.rs | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/crates/exec-harness/src/analysis/mod.rs b/crates/exec-harness/src/analysis/mod.rs
index feed1ab21..9d12738ee 100644
--- a/crates/exec-harness/src/analysis/mod.rs
+++ b/crates/exec-harness/src/analysis/mod.rs
@@ -25,15 +25,20 @@ pub fn perform(commands: Vec<BenchmarkCommand>, mode: MeasurementMode) -> Result
         }
 
         hooks.start_benchmark().unwrap();
-        let status = cmd.status();
+        let result = cmd.spawn().and_then(|mut child| {
+            let pid = child.id();
+            child.wait().map(|status| (pid, status))
+        });
         hooks.stop_benchmark().unwrap();
-        let status = status.context("Failed to execute command")?;
+        let (pid, status) = result.context("Failed to execute command")?;
 
         if !status.success() {
             bail!("Command exited with non-zero status: {status}");
         }
 
-        hooks.set_executed_benchmark(&name_and_uri.uri).unwrap();
+        hooks
+            .set_executed_benchmark_for_pid(pid, &name_and_uri.uri)
+            .unwrap();
     }
 
     Ok(())