killsnoop
diff --git a/tools/killsnoop b/tools/killsnoop
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+#!/usr/bin/python
+#
+# killsnoop Trace signals issued by the kill() syscall.
+# For Linux, uses BCC, eBPF. Embedded C.
+#
+# USAGE: killsnoop [-h] [-t] [-x] [-p PID]
+#
+# Copyright (c) 2015 Brendan Gregg.
+# Licensed under the Apache License, Version 2.0 (the "License")
+#
+# 20-Sep-2015 Brendan Gregg Created this.
+
+from __future__ import print_function
+from bcc import BPF
+import argparse
+
+# arguments
+examples = """examples:
+ ./killsnoop # trace all kill() signals
+ ./killsnoop -t # include timestamps
+ ./killsnoop -x # only show failed kills
+ ./killsnoop -p 181 # only trace PID 181
+"""
+parser = argparse.ArgumentParser(
+ description="Trace signals issued by the kill() syscall",
+ formatter_class=argparse.RawDescriptionHelpFormatter,
+ epilog=examples)
+parser.add_argument("-t", "--timestamp", action="store_true",
+ help="include timestamp on output")
+parser.add_argument("-x", "--failed", action="store_true",
+ help="only show failed opens")
+parser.add_argument("-p", "--pid",
+ help="trace this PID only")
+args = parser.parse_args()
+debug = 0
+
+# define BPF program
+bpf_text = """
+#include <uapi/linux/ptrace.h>
+
+BPF_HASH(args_pid, u32, int);
+BPF_HASH(args_sig, u32, int);
+
+int kprobe__sys_kill(struct pt_regs *ctx, int tpid, int sig)
+{
+ u32 pid = bpf_get_current_pid_tgid();
+
+ FILTER
+ args_pid.update(&pid, &tpid);
+ args_sig.update(&pid, &sig);
+
+ return 0;
+};
+
+int kretprobe__sys_kill(struct pt_regs *ctx)
+{
+ int *tpidp, *sigp, ret = ctx->ax;
+ u32 pid = bpf_get_current_pid_tgid();
+
+ tpidp = args_pid.lookup(&pid);
+ sigp = args_sig.lookup(&pid);
+ if (tpidp == 0 || sigp == 0) {
+ return 0; // missed entry
+ }
+
+ bpf_trace_printk("%d %d %d\\n", *tpidp, *sigp, ret);
+ args_pid.delete(&pid);
+ args_sig.delete(&pid);
+
+ return 0;
+}
+"""
+if args.pid:
+ bpf_text = bpf_text.replace('FILTER',
+ 'if (pid != %s) { return 0; }' % args.pid)
+else:
+ bpf_text = bpf_text.replace('FILTER', '')
+if debug:
+ print(bpf_text)
+
+# initialize BPF
+b = BPF(text=bpf_text)
+
+# header
+if args.timestamp:
+ print("%-14s" % ("TIME(s)"), end="")
+print("%-6s %-16s %-4s %-6s %s" % ("PID", "COMM", "SIG", "TPID", "RESULT"))
+
+start_ts = 0
+
+# format output
+while 1:
+ (task, pid, cpu, flags, ts, msg) = b.trace_fields()
+ (tpid_s, sig_s, ret_s) = msg.split(" ")
+
+ ret = int(ret_s)
+ if (args.failed and (ret >= 0)):
+ continue
+
+ # print columns
+ if args.timestamp:
+ if start_ts == 0:
+ start_ts = ts
+ print("%-14.9f" % (ts - start_ts), end="")
+ print("%-6d %-16s %-4s %-6s %s" % (pid, task, sig_s, tpid_s, ret_s))