tools/perf/scripts/python/net_dropmonitor.py

   1 # Monitor the system for dropped packets and proudce a report of drop locations and counts
   2 # SPDX-License-Identifier: GPL-2.0
   3
   4 from __future__ import print_function
   5
   6 import os
   7 import sys
   8
   9 sys.path.append(os.environ['PERF_EXEC_PATH'] + \
  10         '/scripts/python/Perf-Trace-Util/lib/Perf/Trace')
  11
  12 from perf_trace_context import *
  13 from Core import *
  14 from Util import *
  15
  16 drop_log = {}
  17 kallsyms = []
  18
  19 def get_kallsyms_table():
  20         global kallsyms
  21
  22         try:
  23                 f = open("/proc/kallsyms", "r")
  24         except:
  25                 return
  26
  27         for line in f:
  28                 loc = int(line.split()[0], 16)
  29                 name = line.split()[2]
  30                 kallsyms.append((loc, name))
  31         kallsyms.sort()
  32
  33 def get_sym(sloc):
  34         loc = int(sloc)
  35
  36         # Invariant: kallsyms[i][0] <= loc for all 0 <= i <= start
  37         #            kallsyms[i][0] > loc for all end <= i < len(kallsyms)
  38         start, end = -1, len(kallsyms)
  39         while end != start + 1:
  40                 pivot = (start + end) // 2
  41                 if loc < kallsyms[pivot][0]:
  42                         end = pivot
  43                 else:
  44                         start = pivot
  45
  46         # Now (start == -1 or kallsyms[start][0] <= loc)
  47         # and (start == len(kallsyms) - 1 or loc < kallsyms[start + 1][0])
  48         if start >= 0:
  49                 symloc, name = kallsyms[start]
  50                 return (name, loc - symloc)
  51         else:
  52                 return (None, 0)
  53
  54 def print_drop_table():
  55         print("%25s %25s %25s" % ("LOCATION", "OFFSET", "COUNT"))
  56         for i in drop_log.keys():
  57                 (sym, off) = get_sym(i)
  58                 if sym == None:
  59                         sym = i
  60                 print("%25s %25s %25s" % (sym, off, drop_log[i]))
  61
  62
  63 def trace_begin():
  64         print("Starting trace (Ctrl-C to dump results)")
  65
  66 def trace_end():
  67         print("Gathering kallsyms data")
  68         get_kallsyms_table()
  69         print_drop_table()
  70
  71 # called from perf, when it finds a corresponding event
  72 def skb__kfree_skb(name, context, cpu, sec, nsec, pid, comm, callchain,
  73                    skbaddr, location, protocol, reason):
  74         slocation = str(location)
  75         try:
  76                 drop_log[slocation] = drop_log[slocation] + 1
  77         except:
  78                 drop_log[slocation] = 1