From af0bf0f006813d188bfdd085b5158b7237db96f4 Mon Sep 17 00:00:00 2001
From: Jim Harris <james.r.harris@intel.com>
Date: Fri, 30 Apr 2021 22:14:51 +0000
Subject: [PATCH] scripts: add bpftrace.sh

This script simplifies execution of bpftrace scripts
for SPDK application analysis. The script should be
invoked as:

scripts/bpftrace.sh `pidof spdk_tgt` script.bt

where 'script.bt' is the name of the bpftrace script
you wish to execute.

The script helps simplify the following:

1) replace __EXE__ markers in the bpftrace script with
   the full path of the spdk executable (required for
   usdt probes);  it uses /proc/<pid>/exe to get the
   full path
2) replace __PID__ markers in the bpftrace script with
   the PID of the spdk process under analysis - this
   allows for doing things like filtering system call
   counts for just the SPDK process
3) invoke bpftrace with the -p <pid> option

Signed-off-by: Jim Harris <james.r.harris@intel.com>
Change-Id: Ib271f26efe4ba326d951a7b30f61b22be755dda7
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/7710
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Konrad Sztyber <konrad.sztyber@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Changpeng Liu <changpeng.liu@intel.com>
---
 scripts/bpftrace.sh | 9 +++++++++
 1 file changed, 9 insertions(+)
 create mode 100755 scripts/bpftrace.sh

diff --git a/scripts/bpftrace.sh b/scripts/bpftrace.sh
new file mode 100755
index 000000000..d35714b15
--- /dev/null
+++ b/scripts/bpftrace.sh
@@ -0,0 +1,9 @@
+#!/usr/bin/env bash
+if [ $# -lt 2 ]; then
+	echo "usage: $0 <pid> <script>"
+	exit 1
+fi
+SCRIPTS_DIR=$(readlink -f $(dirname $0))
+BIN_PATH=$(readlink -f /proc/$1/exe)
+BPF_SCRIPT=$(sed "s#__EXE__#${BIN_PATH}#g" "${@:2}" | sed "s#__PID__#${1}#g")
+bpftrace -p $1 -e "$BPF_SCRIPT"