From 3e07fcbe88ca6e9e885bea5e8c4f9bc2bcff8ca0 Mon Sep 17 00:00:00 2001
From: Cole Miller <cole.miller@canonical.com>
Date: Tue, 4 Oct 2022 14:11:13 -0400
Subject: [PATCH 1/2] Add lifecycle function calls for request tracing

Signed-off-by: Cole Miller <cole.miller@canonical.com>
---
 Makefile.am       |  1 +
 src/client.c      |  5 +++--
 src/lifecycle.c   | 15 +++++++++++++++
 src/lifecycle.h   | 10 ++++++++++
 src/replication.c |  3 ++-
 5 files changed, 31 insertions(+), 3 deletions(-)
 create mode 100644 src/lifecycle.c
 create mode 100644 src/lifecycle.h

diff --git a/Makefile.am b/Makefile.am
index 4be26efde..fd063874c 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -19,6 +19,7 @@ libraft_la_SOURCES = \
   src/entry.c \
   src/err.c \
   src/heap.c \
+  src/lifecycle.c \
   src/log.c \
   src/membership.c \
   src/progress.c \
diff --git a/src/client.c b/src/client.c
index 9467a6b28..ccd3e5cd3 100644
--- a/src/client.c
+++ b/src/client.c
@@ -2,6 +2,7 @@
 #include "assert.h"
 #include "configuration.h"
 #include "err.h"
+#include "lifecycle.h"
 #include "log.h"
 #include "membership.h"
 #include "progress.h"
@@ -47,7 +48,7 @@ int raft_apply(struct raft *r,
         goto err;
     }
 
-    QUEUE_PUSH(&r->leader_state.requests, &req->queue);
+    lifecycleRequestStart(r, (struct request *)req);
 
     rv = replicationTrigger(r, index);
     if (rv != 0) {
@@ -96,7 +97,7 @@ int raft_barrier(struct raft *r, struct raft_barrier *req, raft_barrier_cb cb)
         goto err_after_buf_alloc;
     }
 
-    QUEUE_PUSH(&r->leader_state.requests, &req->queue);
+    lifecycleRequestStart(r, (struct request *)req);
 
     rv = replicationTrigger(r, index);
     if (rv != 0) {
diff --git a/src/lifecycle.c b/src/lifecycle.c
new file mode 100644
index 000000000..b7fa4ad31
--- /dev/null
+++ b/src/lifecycle.c
@@ -0,0 +1,15 @@
+#include "lifecycle.h"
+#include "queue.h"
+
+#include <stdlib.h>
+
+void lifecycleRequestStart(struct raft *r, struct request *req)
+{
+    QUEUE_PUSH(&r->leader_state.requests, &req->queue);
+}
+
+void lifecycleRequestEnd(struct raft *r, struct request *req)
+{
+    (void)r;
+    QUEUE_REMOVE(&req->queue);
+}
diff --git a/src/lifecycle.h b/src/lifecycle.h
new file mode 100644
index 000000000..7ed5c8b34
--- /dev/null
+++ b/src/lifecycle.h
@@ -0,0 +1,10 @@
+#ifndef LIFECYCLE_H_
+#define LIFECYCLE_H_
+
+#include "../include/raft.h"
+#include "request.h"
+
+void lifecycleRequestStart(struct raft *r, struct request *req);
+void lifecycleRequestEnd(struct raft *r, struct request *req);
+
+#endif
diff --git a/src/replication.c b/src/replication.c
index 0d73be2f7..e51281463 100644
--- a/src/replication.c
+++ b/src/replication.c
@@ -9,6 +9,7 @@
 #endif
 #include "err.h"
 #include "heap.h"
+#include "lifecycle.h"
 #include "log.h"
 #include "membership.h"
 #include "progress.h"
@@ -454,7 +455,7 @@ static struct request *getRequest(struct raft *r,
         req = QUEUE_DATA(head, struct request, queue);
         if (req->index == index) {
             assert(req->type == type);
-            QUEUE_REMOVE(head);
+            lifecycleRequestEnd(r, req);
             return req;
         }
     }

From 6049dfc77d39001985ad6fd3e894494156e68039 Mon Sep 17 00:00:00 2001
From: Cole Miller <cole.miller@canonical.com>
Date: Tue, 4 Oct 2022 16:18:32 -0400
Subject: [PATCH 2/2] Always pass -fno-omit-frame-pointer

This helps bpftrace generate stack traces.

Signed-off-by: Cole Miller <cole.miller@canonical.com>
---
 Makefile.am | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Makefile.am b/Makefile.am
index fd063874c..b6548a3dd 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,6 +1,9 @@
 ACLOCAL_AMFLAGS = -I m4
 AM_CFLAGS += $(CODE_COVERAGE_CFLAGS)
 
+# Not clobbering the base pointer helps bpftrace construct backtraces
+AM_CFLAGS += -fno-omit-frame-pointer
+
 include_HEADERS = include/raft.h
 
 raftincludedir = $(includedir)/raft