[lttng-dev] Function Tracing Fails
Geneviève Bastien
gbastien at versatic.net
Mon Jul 30 09:50:17 EDT 2018
Hi Paramesh,
One way to know if your app is really compiled with
-finstrument-functions is doing
$ objdump -d my_test_app | grep cyg
You would typically see something like this:
0000000000001250 <__cyg_profile_func_enter at plt>:
1250: ff 25 fa 2d 20 00 jmpq *0x202dfa(%rip) #
204050 <__cyg_profile_func_enter at GLIBC_2.2.5>
0000000000001260 <__cyg_profile_func_exit at plt>:
1260: ff 25 f2 2d 20 00 jmpq *0x202df2(%rip) #
204058 <__cyg_profile_func_exit at GLIBC_2.2.5>
14a8: e8 a3 fd ff ff callq 1250
<__cyg_profile_func_enter at plt>
16d8: e8 83 fb ff ff callq 1260
<__cyg_profile_func_exit at plt>
19c5: e8 86 f8 ff ff callq 1250
<__cyg_profile_func_enter at plt>
19e2: e9 79 f8 ff ff jmpq 1260
<__cyg_profile_func_exit at plt>
1a0d: e8 3e f8 ff ff callq 1250
<__cyg_profile_func_enter at plt>
If you see nothing, as Mathieu said, you can check the individual make
commands and see what flags are being used on the command line.
Geneviève
On 2018-07-29 09:29 PM, paramesh p wrote:
> Hi,
> I am trying to use Function Tracing for my application running in
> 32-bit ARM Platform. I have added below lines in my makefile for
> enabling Trace Data for function tracing
>
> AM_CFLAGS += -g -O0 -finstrument-functions
> AM_CXXFLAGS += -g -O0 -finstrument-functions
>
> **(My App have both C && CPP files, So I added CFLAGS & CXXFLAGS).
>
> I am running below commands,
> $lttng create session1
> $lttng enable-event -u -a --loglevel-only TRACE_DEBUG_FUNCTION
> $lttng start
> $LD_PRELOAD=liblttng-ust-cyg-profile.so.0.0.0 my_test_app
> $lttng start
> $babeltrace /home/root/lttng-traces/session1
>
> Its showing nothing.
>
> I tried with below event-enable command also. There is no data
> $lttng enable-event -u -a --loglevel TRACE_DEBUG_FUNCTION
>
> But If I use the command, "lttng enable-event -u -a" for enabling the
> event, I am getting below output from babeltrace,
>
> [22:25:30.812389281] (+?.?????????) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0xAD1A9000, sopath =
> "/usr/lib/liblttng-ust-cyg-profile.so.0.0.0", size = 10004, mtime =
> 1532324280 }
> [22:25:30.812496469] (+0.000107188) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4DFF0000, sopath = "/usr/lib/xxx.so", size =
> 19540, mtime = 1532369202 }
> [22:25:30.812604177] (+0.000107708) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4E120000, sopath =
> "/usr/lib/libcutils.so.0.0.0", size = 48624, mtime = 1532323462 }
> [22:25:30.812655219] (+0.000051042) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4DC80000, sopath = "/lib/libpthread-2.22.so
> <http://libpthread-2.22.so>", size = 94976, mtime = 1532322845 }
> [22:25:30.812701677] (+0.000046458) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4DB20000, sopath = "/lib/libc-2.22.so
> <http://libc-2.22.so>", size = 1304484, mtime = 1532322845 }
> [22:25:30.812757927] (+0.000056250) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0xAD15B000, sopath =
> "/usr/lib/liblttng-ust.so.0.0.0", size = 315248, mtime = 1532324280 }
> [22:25:30.812814229] (+0.000056302) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0xAD149000, sopath =
> "/usr/lib/liblttng-ust-tracepoint.so.0.0.0", size = 35624, mtime =
> 1532324280 }
> [22:25:30.812860635] (+0.000046406) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4DEC0000, sopath = "/lib/librt-2.22.so
> <http://librt-2.22.so>", size = 28380, mtime = 1532322845 }
> [22:25:30.812904438] (+0.000043803) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4DCB0000, sopath = "/lib/libdl-2.22.so
> <http://libdl-2.22.so>", size = 11236, mtime = 1532322845 }
> [22:25:30.812959125] (+0.000054687) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4DE10000, sopath =
> "/usr/lib/liburcu-bp.so.2.0.0", size = 29052, mtime = 1532323584 }
> [22:25:30.813013969] (+0.000054844) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4DE00000, sopath =
> "/usr/lib/liburcu-cds.so.2.0.0", size = 26152, mtime = 1532323584 }
> [22:25:30.813485479] (+0.000471510) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4DD60000, sopath =
> "/usr/lib/liburcu-common.so.2.0.0", size = 13084, mtime = 1532323584 }
> [22:25:30.813600792] (+0.000115313) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4DAE0000, sopath = "/lib/ld-2.22.so
> <http://ld-2.22.so>", size = 139632, mtime = 1532322845 }
> [22:25:30.813663656] (+0.000062864) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4DFC0000, sopath = "/usr/lib/xxx.so.1.0.0",
> size = 19456, mtime = 1532323510 }
> [22:25:30.813720635] (+0.000056979) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4E030000, sopath = "/usr/lib/xxx.so.1.6.0",
> size = 142164, mtime = 1532323441 }
> [22:25:30.813776990] (+0.000056355) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4E060000, sopath = "/usr/lib/xxx.so.0.0.0",
> size = 265304, mtime = 1532324468 }
> [22:25:30.813843917] (+0.000066927) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4DEA0000, sopath = "/usr/lib/xxx.so.0.0.0",
> size = 84016, mtime = 1532324363 }
> [22:25:30.813884385] (+0.000040468) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4DFE0000, sopath = "/usr/lib/xxx.so", size =
> 34204, mtime = 1532324426 }
> [22:25:30.813940479] (+0.000056094) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4DFD0000, sopath = "/usr/lib/xxx.so", size =
> 7388, mtime = 1532324388 }
> [22:25:30.813993604] (+0.000053125) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4E000000, sopath = "/usr/lib/xxx.so", size =
> 33152, mtime = 1532323414 }
> [22:25:30.814049333] (+0.000055729) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4DEE0000, sopath =
> "/usr/lib/libstdc++.so.6.0.20", size = 869236, mtime = 1532323320 }
> [22:25:30.814094177] (+0.000044844) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4DCD0000, sopath = "/lib/libm-2.22.so
> <http://libm-2.22.so>", size = 441372, mtime = 1532322845 }
> [22:25:30.814234177] (+0.000140000) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4DE80000, sopath = "/lib/libgcc_s.so.1",
> size = 118608, mtime = 1532323098 }
> [22:25:30.814427615] (+0.000193438) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x8000, sopath = "/usr/bin/my_test_app", size
> = 54540, mtime = 1532369202 }
> [22:25:30.828436677] (+0.014009062) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0xAEC57000, sopath =
> "/usr/lib/liblttng-ust-cyg-profile.so.0.0.0", size = 10004, mtime =
> 1532324280 }
> [22:25:30.828634958] (+0.000198281) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 1 }, { baddr = 0x4DCD0000, sopath = "/lib/libm-2.22.so
> <http://libm-2.22.so>", size = 441372, mtime = 1532322845 }
> [22:25:30.829786104] (+0.001151146) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 0 }, { baddr = 0x4DB20000, sopath = "/lib/libc-2.22.so
> <http://libc-2.22.so>", size = 1304484, mtime = 1532322845 }
> [22:25:30.829910219] (+0.000124115) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 0 }, { baddr = 0xAEC09000, sopath =
> "/usr/lib/liblttng-ust.so.0.0.0", size = 315248, mtime = 1532324280 }
> [22:25:30.829996000] (+0.000085781) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 0 }, { baddr = 0xAEBF7000, sopath =
> "/usr/lib/liblttng-ust-tracepoint.so.0.0.0", size = 35624, mtime =
> 1532324280 }
> [22:25:30.830067510] (+0.000071510) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 0 }, { baddr = 0x4DEC0000, sopath = "/lib/librt-2.22.so
> <http://librt-2.22.so>", size = 28380, mtime = 1532322845 }
> [22:25:30.830118031] (+0.000050521) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 0 }, { baddr = 0x4DCB0000, sopath = "/lib/libdl-2.22.so
> <http://libdl-2.22.so>", size = 11236, mtime = 1532322845 }
> [22:25:30.830175010] (+0.000056979) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 0 }, { baddr = 0x4DE10000, sopath =
> "/usr/lib/liburcu-bp.so.2.0.0", size = 29052, mtime = 1532323584 }
> [22:25:30.830245271] (+0.000070261) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 0 }, { baddr = 0x4DE00000, sopath =
> "/usr/lib/liburcu-cds.so.2.0.0", size = 26152, mtime = 1532323584 }
> [22:25:30.830316521] (+0.000071250) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 0 }, { baddr = 0x4DD60000, sopath =
> "/usr/lib/liburcu-common.so.2.0.0", size = 13084, mtime = 1532323584 }
> [22:25:34.384458499] (+3.554141978) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 2 }, { baddr = 0xAF584000, sopath =
> "/usr/lib/liblttng-ust-cyg-profile.so.0.0.0", size = 10004, mtime =
> 1532324280 }
> [22:25:34.385048967] (+0.000590468) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 2 }, { baddr = 0x4DCD0000, sopath = "/lib/libm-2.22.so
> <http://libm-2.22.so>", size = 441372, mtime = 1532322845 }
> [22:25:34.385146415] (+0.000097448) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 2 }, { baddr = 0x4DB20000, sopath = "/lib/libc-2.22.so
> <http://libc-2.22.so>", size = 1304484, mtime = 1532322845 }
> [22:25:34.385251832] (+0.000105417) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 2 }, { baddr = 0xAF536000, sopath =
> "/usr/lib/liblttng-ust.so.0.0.0", size = 315248, mtime = 1532324280 }
> [22:25:34.385354228] (+0.000102396) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 2 }, { baddr = 0xAF524000, sopath =
> "/usr/lib/liblttng-ust-tracepoint.so.0.0.0", size = 35624, mtime =
> 1532324280 }
> [22:25:34.385444384] (+0.000090156) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 2 }, { baddr = 0x4DEC0000, sopath = "/lib/librt-2.22.so
> <http://librt-2.22.so>", size = 28380, mtime = 1532322845 }
> [22:25:34.385530165] (+0.000085781) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 2 }, { baddr = 0x4DCB0000, sopath = "/lib/libdl-2.22.so
> <http://libdl-2.22.so>", size = 11236, mtime = 1532322845 }
> [22:25:34.385607613] (+0.000077448) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 2 }, { baddr = 0x4DE10000, sopath =
> "/usr/lib/liburcu-bp.so.2.0.0", size = 29052, mtime = 1532323584 }
> [22:25:34.385677978] (+0.000070365) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 2 }, { baddr = 0x4DE00000, sopath =
> "/usr/lib/liburcu-cds.so.2.0.0", size = 26152, mtime = 1532323584 }
> [22:25:34.385773655] (+0.000095677) ZZZ ust_baddr_statedump:soinfo: {
> cpu_id = 2 }, { baddr = 0x4DD60000, sopath =
> "/usr/lib/liburcu-common.so.2.0.0", size = 13084, mtime = 1532323584 }
>
> Note: I have changed the Target Name as 'ZZZ' and some of the library
> name as 'xxx' in the above log for some confidential issues.
>
>
> Please guide me where I am making mistake and Please give your input
> on how to check the application compiled with function instrument
> information for tracing. I verified that application compiled with
> debugging information, by running gdb command. Below is the output of
> gdb command,
>
> /usr/bin # gdb my_test_app
> GNU gdb (GDB) 7.9.1
> Copyright (C) 2015 Free Software Foundation, Inc.
> License GPLv3+: GNU GPL version 3 or later
> <http://gnu.org/licenses/gpl.html>
> This is free software: you are free to change and redistribute it.
> There is NO WARRANTY, to the extent permitted by law. Type "show copying"
> and "show warranty" for details.
> This GDB was configured as "arm-oe-linux-gnueabi".
> Type "show configuration" for configuration details.
> For bug reporting instructions, please see:
> <http://www.gnu.org/software/gdb/bugs/>.
> Find the GDB manual and other documentation resources online at:
> <http://www.gnu.org/software/gdb/documentation/>.
> For help, type "help".
> Type "apropos word" to search for commands related to "word"...
> Reading symbols from my_test_app...done.
> (gdb)
> (gdb) exit
> I am not sure whether it is compiled with finstrumentation information.
>
> Thanks in Advance,
> Paramesh
>
>
>
>
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> lttng-dev at lists.lttng.org
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