[dpdk-users] Viewing DPDK Trace with babeltrace

[Utkarsh Pandey <utkarshece80587@gmail.com>]

Hi All,

I was trying to test the DPDK Trace feature available in DPDK 20.08.
I created a simple DPDK program to send packets in which I call the trace
function with simple strings. I call rte_trace_save() after that.
The trace folder is created in the designated directory. It has some files
of the format *channel0_X (X = 1.2 ..)* and a *metadata* file.

However, when I try to view the traces using *babeltrace *or *babeltrace2, * I
get the following error:


*"[error] at line 579: token "size_t": syntax error, unexpected
IDENTIFIER".*
I tested with following babeltrace versions:
1. babeltrace1 : 1.5.8 (built from source) and 1.2.4 (rpm for centOS 7)
2. babeltrace2 :  2.0.3  (built from source)

I am running CentOS 7.4.


* Complete output on running babeltrace1:*












*[root@j3cassini dpdk-traces]# babeltrace
rte-2020-11-30-AM-11-10-22/[error] at line 579: token "size_t": syntax
error, unexpected IDENTIFIER[error] Error creating AST[warning] Unable to
open trace metadata for path "rte-2020-11-30-AM-11-10-22".[warning]
[Context] Cannot open_trace of format ctf at path
rte-2020-11-30-AM-11-10-22.[warning] [Context] cannot open trace
"rte-2020-11-30-AM-11-10-22" from rte-2020-11-30-AM-11-10-22/ for
reading.[error] Cannot open any trace for reading.[error] opening trace
"rte-2020-11-30-AM-11-10-22/" for reading.[error] none of the specified
trace paths could be opened.*

*Complete output on running babeltrace2:*

















*[root@j3cassini dpdk-traces]# babeltrace2 rte-2020-11-30-AM-11-10-22/12-02
15:15:49.563 246238 246238 E PLUGIN/CTF/META/PARSER yyerror@parser.y:944 At
line 579 in metadata stream: syntax error, unexpected IDENTIFIER:
token="size_t"12-02 15:15:49.563 246238 246238 E PLUGIN/CTF/META/DECODER
ctf_metadata_decoder_append_content@decoder.c:289 [N/A] Cannot create the
metadata AST out of the metadata text: mdec-addr=0xcb183012-02 15:15:49.563
246238 246238 W PLUGIN/SRC.CTF.FS/QUERY support_info_query@query.c:478
cannot append metadata content: metadata-decoder-status=-212-02
15:15:49.564 246238 246238 W LIB/QUERY-EXECUTOR
bt_query_executor_query@query-executor.c:249 Component class's "query"
method failed: query-exec-addr=0xcb22b0, cc-addr=0xcaff40, cc-type=SOURCE,
cc-name="fs", cc-partial-descr="Read CTF traces from the file sy",
cc-is-frozen=0, cc-so-handle-addr=0xcaecd0,
cc-so-handle-path="/usr/local/lib/babeltrace2/plugins/babeltrace-plugin-ctf.so",
object="babeltrace.support-info", params-addr=0xcb0750, params-type=MAP,
params-element-count=2, log-level=WARNING12-02 15:15:49.564 246238 246238 E
CLI-CFG-SRC-AUTO-DISC support_info_query_all_sources@autodisc.c:509
babeltrace.support-info query failed.12-02 15:15:49.564 246238 246238 E CLI
main@babeltrace2.c:2663 Command-line error: retcode=1ERROR:    [Babeltrace
CLI] (babeltrace2.c:2663)  Command-line error: retcode=1CAUSED BY [Source
auto-discovery] (autodisc.c:509)  babeltrace.support-info query
failed.CAUSED BY [libbabeltrace2] (query-executor.c:249)  Component class's
"query" method failed: query-exec-addr=0xcb22b0, cc-addr=0xcaff40,
cc-type=SOURCE, cc-name="fs",  cc-partial-descr="Read CTF traces from the
file sy", cc-is-frozen=0, cc-so-handle-addr=0xcaecd0,
cc-so-handle-path="/usr/local/lib/babeltrace2/plugins/babeltrace-plugin-ctf.so",
object="babeltrace.support-info",  params-addr=0xcb0750, params-type=MAP,
params-element-count=2, log-level=WARNING*
Questions:
1.  Why is babeltrace failing to inspect the traces?
2. Has anyone used babeltrace to view DPDK traces? If not, what other tools
are recommended?


Thanks and regards,
Utkarsh Pandey