Fixes for address calculation

The calculation of function address in non-shared libraries was incorrect. Fix it. Signed-off-by: Brenden Blanco <[email protected]>
iovisor · Jan 28, 2016 · 7468195 · 7468195
1 parent 948cefe
commit 7468195
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Showing 3 changed files with 8 additions and 33 deletions.
diff --git a/src/cc/libbpf.c b/src/cc/libbpf.c
@@ -234,7 +234,7 @@ static int bpf_attach_tracing_event(int progfd, const char *event_path,
  attr.wakeup_events = 1;
  pfd = syscall(__NR_perf_event_open, &attr, pid, cpu, group_fd, PERF_FLAG_FD_CLOEXEC);
  if (pfd < 0) {
- perror("perf_event_open");
+ fprintf(stderr, "perf_event_open(%s/id): %s\n", event_path, strerror(errno));
  goto error;
  }
  perf_reader_set_fd(reader, pfd);

diff --git a/src/python/bcc/__init__.py b/src/python/bcc/__init__.py
@@ -765,7 +765,7 @@ def _check_path_symbol(cls, name, sym, addr):
  if not addr:
  raise Exception("could not determine address of symbol %s" % sym)
 
- return (path, load_addr+addr)
+ return (path, addr-load_addr)
 
  def attach_uprobe(self, name="", sym="", addr=None,
  fn_name="", pid=-1, cpu=0, group_fd=-1):

diff --git a/tests/cc/test_uprobes.py b/tests/cc/test_uprobes.py
@@ -5,34 +5,8 @@
 import bcc
 import ctypes
 import os
-import re
-import struct
-import time
 import unittest
 
-## code from ctypes impl
-#if struct.calcsize("l") == 4:
-# machine = os.uname()[4] + "-32"
-#else:
-# machine = os.uname()[4] + "-64"
-#mach_map = {
-# "x86_64-64": "libc6,x86-64",
-# "ppc64-64": "libc6,64bit",
-# "sparc64-64": "libc6,64bit",
-# "s390x-64": "libc6,64bit",
-# "ia64-64": "libc6,IA-64",
-#}
-#abi_type = mach_map.get(machine, "libc6")
-#
-#def find_library_fullpath(name):
-# expr = r"\s+lib%s\.[^\s]+\s+\(%s, [^)]+[^/]+([^\s]+)" % (name, abi_type)
-# with os.popen("/sbin/ldconfig -p 2>/dev/null") as f:
-# data = f.read()
-# res = re.search(expr, data)
-# if not res:
-# return None
-# return res.group(1)
-
 class TestUprobes(unittest.TestCase):
  def test_simple_library(self):
  text = """
@@ -58,6 +32,7 @@ def test_simple_library(self):
  libc.malloc_stats.argtypes = []
  libc.malloc_stats()
  self.assertEqual(b["stats"][ctypes.c_int(0)].value, 2)
+ b.detach_uretprobe(name="c", sym="malloc_stats")
  b.detach_uprobe(name="c", sym="malloc_stats")
 
  def test_simple_binary(self):
@@ -74,14 +49,14 @@ def test_simple_binary(self):
  incr(0);
  return 0;
 }"""
- text = text.replace("PID", "%d" % os.getpid())
  b = bcc.BPF(text=text)
- b.attach_uprobe(name="/usr/bin/python2", sym="main", fn_name="count")
- b.attach_uretprobe(name="/usr/bin/python2", sym="main", fn_name="count")
- with os.popen("/usr/bin/python2 -V") as f:
+ b.attach_uprobe(name="/usr/bin/python", sym="main", fn_name="count")
+ b.attach_uretprobe(name="/usr/bin/python", sym="main", fn_name="count")
+ with os.popen("/usr/bin/python -V") as f:
  pass
  self.assertGreater(b["stats"][ctypes.c_int(0)].value, 0)
- b.detach_uprobe(name="/usr/bin/python2", sym="main")
+ b.detach_uretprobe(name="/usr/bin/python", sym="main")
+ b.detach_uprobe(name="/usr/bin/python", sym="main")
 
 if __name__ == "__main__":
  unittest.main()