toos: argdist: support [-t TID] filter

It's helpful to measure argdist in multi-thread case, so we can
distinguish workload is balanced of not.

Signed-off-by: zhenwei pi <[email protected]>

man/man8/argdist.8

@@ -2,7 +2,7 @@
 .SH NAME
 argdist \- Trace a function and display a histogram or frequency count of its parameter values. Uses Linux eBPF/bcc.
 .SH SYNOPSIS
-.B argdist [-h] [-p PID] [-z STRING_SIZE] [-i INTERVAL] [-d DURATION] [-n COUNT] [-v] [-T TOP] [-H specifier] [-C specifier] [-I header]
+.B argdist [-h] [-p PID] [-z STRING_SIZE] [-i INTERVAL] [-d DURATION] [-n COUNT] [-v] [-T TOP] [-H specifier] [-C specifier] [-I header] [-t TID]
 .SH DESCRIPTION
 argdist attaches to function entry and exit points, collects specified parameter
 values, and stores them in a histogram or a frequency collection that counts
@@ -20,6 +20,9 @@ Print usage message.
 \-p PID
 Trace only functions in the process PID.
 .TP
+\-t TID
+Trace only functions in the thread TID.
+.TP
 \-z STRING_SIZE
 When collecting string arguments (of type char*), collect up to STRING_SIZE 
 characters. Longer strings will be truncated.

tools/argdist.py

@@ -5,6 +5,7 @@
 #
 # USAGE: argdist [-h] [-p PID] [-z STRING_SIZE] [-i INTERVAL] [-n COUNT] [-v]
 # [-c] [-T TOP] [-C specifier] [-H specifier] [-I header]
+# [-t TID]
 #
 # Licensed under the Apache License, Version 2.0 (the "License")
 # Copyright (C) 2016 Sasha Goldshtein.
@@ -55,6 +56,7 @@ def _generate_entry(self):
  u32 __pid = __pid_tgid; // lower 32 bits
  u32 __tgid = __pid_tgid >> 32; // upper 32 bits
  PID_FILTER
+ TID_FILTER
  COLLECT
  return 0;
 }
@@ -63,6 +65,7 @@ def _generate_entry(self):
  text = text.replace("SIGNATURE",
  "" if len(self.signature) == 0 else ", " + self.signature)
  text = text.replace("PID_FILTER", self._generate_pid_filter())
+ text = text.replace("TID_FILTER", self._generate_tid_filter())
  collect = ""
  for pname in self.args_to_probe:
  param_hash = self.hashname_prefix + pname
@@ -184,6 +187,7 @@ def __init__(self, tool, type, specifier):
  self.usdt_ctx = None
  self.streq_functions = ""
  self.pid = tool.args.pid
+ self.tid = tool.args.tid
  self.cumulative = tool.args.cumulative or False
  self.raw_spec = specifier
  self.probe_user_list = set()
@@ -348,6 +352,12 @@ def _generate_pid_filter(self):
  else:
  return ""
 
+ def _generate_tid_filter(self):
+ if self.tid is not None and not self.is_user:
+ return "if (__pid != %d) { return 0; }" % self.tid
+ else:
+ return ""
+
  def generate_text(self):
  program = ""
  probe_text = """
@@ -362,6 +372,7 @@ def generate_text(self):
  u32 __pid = __pid_tgid; // lower 32 bits
  u32 __tgid = __pid_tgid >> 32; // upper 32 bits
  PID_FILTER
+ TID_FILTER
  PREFIX
  KEY_EXPR
  if (!(FILTER)) return 0;
@@ -391,6 +402,8 @@ def generate_text(self):
  program = program.replace("SIGNATURE", signature)
  program = program.replace("PID_FILTER",
  self._generate_pid_filter())
+ program = program.replace("TID_FILTER",
+ self._generate_tid_filter())
 
  decl = self._generate_hash_decl()
  key_expr = self._generate_key_assignment()
@@ -602,6 +615,8 @@ def __init__(self):
  epilog=Tool.examples)
  parser.add_argument("-p", "--pid", type=int,
  help="id of the process to trace (optional)")
+ parser.add_argument("-t", "--tid", type=int,
+ help="id of the thread to trace (optional)")
  parser.add_argument("-z", "--string-size", default=80,
  type=int,
  help="maximum string size to read from char* arguments")

tools/argdist_example.txt

@@ -345,6 +345,7 @@ Trace a function and display a summary of its parameter values.
 optional arguments:
  -h, --help show this help message and exit
  -p PID, --pid PID id of the process to trace (optional)
+ -t TID, --tid TID id of the thread to trace (optional)
  -z STRING_SIZE, --string-size STRING_SIZE
  maximum string size to read from char* arguments
  -i INTERVAL, --interval INTERVAL