Add example user profile btrace script.

With and OK mpi@

diff --git a/share/btrace/Makefile b/share/btrace/Makefile
index 900b5f6..acca289 100644 (file)
--- a/share/btrace/Makefile
+++ b/share/btrace/Makefile
@@ -1,6 +1,6 @@
-#      $OpenBSD: Makefile,v 1.1 2021/10/23 19:37:35 mpi Exp $
+#      $OpenBSD: Makefile,v 1.2 2023/05/12 14:34:00 claudio Exp $
 
-FILES= kprofile.bt runqlat.bt
+FILES= kprofile.bt runqlat.bt uprofile.bt
 NOOBJ= noobj
 
 install:

diff --git a/share/btrace/uprofile.bt b/share/btrace/uprofile.bt
new file mode 100644 (file)
index 0000000..17ce622
--- /dev/null
+++ b/share/btrace/uprofile.bt
@@ -0,0 +1,17 @@
+/*     $OpenBSD: uprofile.bt,v 1.1 2023/05/12 14:34:00 claudio Exp $   */
+
+/*
+ * uprofile.bt Userland profiling (stack sampling) at 100Hz.
+ *
+ * To produce a FlameGraph process the output with stackcollapse-bpftrace.pl
+ * and flamegraph.pl found in:
+ *     https://github.com/brendangregg/FlameGraph
+ *
+ * The PID of the to be monitored process is the first optional argument to
+ * btrace(8).
+ * This only works for a single static binary where everything was compiled
+ * with -fno-omit-frame-pointer.
+ */
+profile:hz:100 / pid == $1 / {
+       @[ustack] = count();
+}