├── README.md
└── gdbprof.py


/README.md:
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 1 | gdbprof
 2 | =======
 3 | A wall clock time-based profiler powered by GDB and its Python API. Heavily
 4 | inspired by [poor man's profiler](http://poormansprofiler.org/).
 5 | 
 6 | Rationale
 7 | ---------
 8 | If there's something strange in your neighborhood (like X consuming 75% CPU in
 9 | `memcpy()` which `perf` can't trace), who you gonna call? `gdb`! Of course, if
10 | you're lazy like me, you don't want to spend too much time hitting
11 | <kbd>Ctrl</kbd>+<kbd>C</kbd>.
12 | 
13 | Caveats
14 | -------
15 | This is hack layered upon hack upon hack. See the source code if you want to
16 | know how it "works". With the current state of gdb's Python affairs, it's
17 | impossible to do it cleanly, but I think it's slightly better than an
18 | expect-based approach because of the lower latency. **Use with CAUTION!**
19 | 
20 | Also, I recommend **attaching** to a running process, rather than starting it
21 | from gdb. You'll need to hold down <kbd>Ctrl</kbd>+<kbd>C</kbd> to stop it if
22 | you start it from `gdb`, as you need to interrupt `gdb`, not the process (I need
23 | to handle this better).
24 | 
25 | Example
26 | -------
27 | ```
28 | (gdb) source gdbprof.py
29 | (gdb) profile begin
30 | ..................................................^C
31 | Profiling complete with 50 samples.
32 | 27      poll->None->None->xcb_wait_for_reply->_XReply->None->None->intel_update_renderbuffers->intel_prepare_render->None->None->None->None->None->None->None->None->None->None->None->None->__libc_start_main->None->None->None
33 | 10      nanosleep->usleep->None->None->None->None->__libc_start_main->None->None->None
34 | 4       poll->None->None->xcb_wait_for_reply->_XReply->None->None->intel_update_renderbuffers->intel_prepare_render->None->None->None->None->__libc_start_main->None->None->None
35 | 2       poll->None->None->xcb_wait_for_reply->_XReply->None->None->intel_update_renderbuffers->intel_prepare_render->None->None->None->None->None->None->None->None->None->None->None->None->None->None->__libc_start_main->None->None->None
36 | 1       gettimeofday->SDL_GetTicks->None->SDL_PumpEvents->None->None->None->None->None->None->None->None->None->None->None->None->None->None->None->None->None->__libc_start_main->None->None->None
37 | 1       recv->None->None->None->None->_XEventsQueued->XFlush->None->None->SDL_PumpEvents->SDL_PollEvent->None->None->__libc_start_main->None->None->None
38 | 1       poll->None->None->xcb_wait_for_reply->_XReply->None->None->None->None->None->None->None->None->None->None->None->None->None->None->None->__libc_start_main->None->None->None
39 | 1       ioctl->drmIoctl->None->_intel_batchbuffer_flush->intelFinish->None->None->None->None->None->None->__libc_start_main->None->None->None
40 | 1       poll->None->None->xcb_wait_for_reply->_XReply->None->None->intel_update_renderbuffers->intel_prepare_render->None->None->None->None->None->None->__libc_start_main->None->None->None
41 | 1       None->brw_upload_state->brw_draw_prims->vbo_exec_vtx_flush->None->vbo_exec_FlushVertices->_mesa_PolygonOffset->None->None->None->None->None->None->None->None->None->None->None->None->None->None->None->None->None->None->None->None->None->__libc_start_main->None->None->None
42 | 1       glDisable->None->None->None->None->None->None->None->None->None->None->None->None->None->None->None->None->None->None->None->__libc_start_main->None->None->None
43 | (gdb)
44 | ```
45 | 


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/gdbprof.py:
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  1 | # -*- coding: utf-8 -*-
  2 | # Copyright (c) 2012 Mak Nazečić-Andrlon
  3 | #
  4 | # Permission is hereby granted, free of charge, to any person obtaining a copy
  5 | # of this software and associated documentation files (the "Software"), to deal
  6 | # in the Software without restriction, including without limitation the rights
  7 | # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  8 | # copies of the Software, and to permit persons to whom the Software is
  9 | # furnished to do so, subject to the following conditions:
 10 | #
 11 | # The above copyright notice and this permission notice shall be included in all
 12 | # copies or substantial portions of the Software.
 13 | #
 14 | # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 15 | # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 16 | # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 17 | # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 18 | # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 19 | # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 20 | # SOFTWARE.
 21 | 
 22 | import gdb
 23 | from collections import defaultdict
 24 | from time import sleep
 25 | import os
 26 | import signal
 27 | 
 28 | def get_call_chain():
 29 |     function_names = []
 30 |     frame = gdb.newest_frame()
 31 |     while frame is not None:
 32 |         function_names.append(frame.name())
 33 |         frame = frame.older()
 34 | 
 35 |     return tuple(function_names)
 36 | 
 37 | class Function:
 38 | 
 39 |     def __init__(self, name, indent):
 40 |         self.name = name
 41 |         self.indent = indent
 42 |         self.subfunctions = []
 43 | 
 44 |         # count of times we terminated here
 45 |         self.count = 0
 46 | 
 47 |     def add_count(self):
 48 |         self.count += 1
 49 | 
 50 |     def get_samples(self):
 51 |         _count = self.count
 52 |         for function in self.subfunctions:
 53 |             _count += function.get_samples()
 54 |         return _count
 55 | 
 56 |     def get_percent(self, total):
 57 |         return 100.0 * self.get_samples() / total
 58 | 
 59 |     def get_name(self):
 60 |         return self.name;
 61 | 
 62 |     def get_func(self, name):
 63 |         for function in self.subfunctions:
 64 |           if function.get_name() == name:
 65 |             return function
 66 |         return None
 67 | 
 68 |     def get_or_add_func(self, name):
 69 |         function = self.get_func(name);
 70 |         if function is not None:
 71 |             return function; 
 72 |         function = Function(name, self.indent)
 73 |         self.subfunctions.append(function)
 74 |         return function
 75 | 
 76 |     def print_samples(self, depth):
 77 |         print "%s%s - %s" % (' ' * (self.indent * depth), self.get_samples(), self.name)
 78 |         for function in self.subfunctions:
 79 |             function.print_samples(depth+1)
 80 | 
 81 |     def print_percent(self, prefix, total):
 82 | #        print "%s%0.2f - %s" % (' ' * (self.indent * depth), self.get_percent(total), self.name)
 83 |         subfunctions = {}
 84 |         for function in self.subfunctions:
 85 |             subfunctions[function.name] = function.get_percent(total)
 86 |         
 87 |         i = 0
 88 |         for name, value in sorted(subfunctions.iteritems(), key=lambda (k,v): (v,k), reverse=True):
 89 |             new_prefix = '' 
 90 |             if i + 1 == len(self.subfunctions):
 91 |                new_prefix += '  '
 92 |             else:
 93 |                new_prefix += '| '
 94 | 
 95 |             print "%s%s%0.2f%% %s" % (prefix, "+ ", value, name)
 96 | 
 97 |             # Don't descend for very small values
 98 |             if value < 0.1:
 99 |                 continue;
100 | 
101 |             self.get_func(name).print_percent(prefix + new_prefix, total)
102 |             i += 1
103 | 
104 |     def add_frame(self, frame):
105 |         if frame is None:
106 |             self.count += 1
107 |         else:
108 |             function = self.get_or_add_func(frame.name())
109 |             function.add_frame(frame.older())
110 | 
111 |     def inverse_add_frame(self, frame):
112 |         if frame is None:
113 |             self.count += 1
114 |         else:
115 |             function = self.get_or_add_func(frame.name())
116 |             function.inverse_add_frame(frame.newer())
117 | 
118 | class ProfileCommand(gdb.Command):
119 |     """Wall clock time profiling leveraging gdb for better backtraces."""
120 | 
121 |     def __init__(self):
122 |         super(ProfileCommand, self).__init__("profile", gdb.COMMAND_RUNNING,
123 |                                              gdb.COMPLETE_NONE, True)
124 | 
125 | class ProfileBeginCommand(gdb.Command):
126 |     """Profile an application against wall clock time.
127 |        profile begin [DURING] [PERIOD]
128 |        DURING is the runtime of profiling in seconds.
129 |        The default DURING is 200 seconds.
130 |        PERIOD is the sampling interval in seconds.
131 |        The default PERIOD is 0.1 seconds.
132 |     """
133 | 
134 |     def __init__(self):
135 |         super(ProfileBeginCommand, self).__init__("profile begin",
136 |                                                   gdb.COMMAND_RUNNING)
137 | 
138 |     def invoke(self, argument, from_tty):
139 |         self.dont_repeat()
140 |         
141 |         runtime = 20
142 |         period = 0.1
143 | 
144 |         args = gdb.string_to_argv(argument)
145 | 
146 |         if len(args) > 0:
147 |             try:
148 |                 runtime = int(args[0]) 
149 |                 if len(args) > 1: 
150 |                     try:
151 |                         period = float(args[1])
152 |                     except ValueError:
153 |                         print("Invalid number \"%s\"." % args[1])
154 |                         return
155 |             except ValueError:
156 |                 print("Invalid number \"%s\"." % args[0])
157 |                 return
158 | 
159 |         def breaking_continue_handler(event):
160 |             sleep(period)
161 |             os.kill(gdb.selected_inferior().pid, signal.SIGINT)
162 | 
163 | #        call_chain_frequencies = defaultdict(lambda: defaultdict(lambda: defaultdict(int)))
164 |         top = Function("Top", 2)
165 |         sleeps = 0
166 | 
167 |         threads = {}
168 |         for i in xrange(0,runtime):
169 |           gdb.events.cont.connect(breaking_continue_handler)
170 |           gdb.execute("continue", to_string=True)
171 |           gdb.events.cont.disconnect(breaking_continue_handler)
172 | 
173 |           for inf in gdb.inferiors():
174 |             inum = inf.num
175 |             for th in inf.threads():
176 |               thn = th.num
177 |               th.switch()
178 | #              call_chain_frequencies[inum][thn][get_call_chain()] += 1
179 |               frame = gdb.newest_frame()
180 |               while (frame.older() != None):
181 |                 frame = frame.older()
182 | #              top.inverse_add_frame(frame);
183 | #              top.add_frame(gdb.newest_frame())
184 |               if thn not in threads:
185 |                 threads[thn] = Function(str(thn), 2)
186 |               threads[thn].inverse_add_frame(frame)
187 | 
188 |           sleeps += 1
189 |           gdb.write(".")
190 |           gdb.flush(gdb.STDOUT)
191 | 
192 |         print "";
193 |         for thn, function in sorted(threads.iteritems()):
194 |           print ""
195 |           print "Thread: %s" % thn
196 |           print ""
197 |           function.print_percent("", function.get_samples())
198 | #        top.print_percent("", top.get_samples())
199 | 
200 | #        print("\nProfiling complete with %d samples." % sleeps)
201 | #        for inum, i_chain_frequencies in sorted(call_chain_frequencies.iteritems()):
202 | #            print ""
203 | #            print "INFERIOR NUM: %s" % inum
204 | #            print ""
205 | #            for thn, t_chain_frequencies in sorted (i_chain_frequencies.iteritems()):
206 | #                print ""
207 | #                print "THREAD NUM: %s" % thn
208 | #                print ""
209 | #
210 | #                for call_chain, frequency in sorted(t_chain_frequencies.iteritems(), key=lambda x: x[1], reverse=True):
211 | #                    print("%d\t%s" % (frequency, '->'.join(str(i) for i in call_chain)))
212 | #
213 | #        for call_chain, frequency in sorted(call_chain_frequencies.iteritems(), key=lambda x: x[1], reverse=True):
214 | #            print("%d\t%s" % (frequency, '->'.join(str(i) for i in call_chain)))
215 | 
216 | 
217 |         pid = gdb.selected_inferior().pid
218 |         os.kill(pid, signal.SIGSTOP)  # Make sure the process does nothing until
219 |                                       # it's reattached.
220 |         gdb.execute("detach", to_string=True)
221 |         gdb.execute("attach %d" % pid, to_string=True)
222 |         os.kill(pid, signal.SIGCONT)
223 |         gdb.execute("continue", to_string=True)
224 | 
225 | ProfileCommand()
226 | ProfileBeginCommand()
227 | 


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