On Wed, 12 May 2021 15:51:52 +0200
Jerome Marchand <jmarchan@xxxxxxxxxx> wrote:
> Hi,
>
> Streams, and thus trace-cmd profile, are not working. A simple
> "trace-cmd profile ls" command exit with the following message
> "Creating stream for 0". I've been looking at it and the issue is that
> tracecmd_read_headers() tries to read the cmdlines, cpus and options
> sections that have not been written to the temporary file when called
> from trace_stream_init().
>
> AFAICT, it is caused by the two following patches:
>
> commit 1eea02a4 ("trace-cmd: Write saved cmdlines in the trace file at
> the end of the trace.") which moved the writing of cmdlines from
> create_file_fd() to tracecmd_create_file_latency() and
> tracecmd_append_cpu_data()
>
> commit 5d4d7ec3 ("trace-cmd: Move reading of trace.dat options to
> tracecmd_read_headers()") which moved the reading of options and cpu
> datas to tracecmd_read_headers().
>
Thanks for the report. I'm not surprised, profiling and streams have not
been given the love they deserve (been focusing on host/guest tracing
recently).
Can you fill out a bug report on bugzilla?
https://bugzilla.kernel.org/buglist.cgi?component=Trace-cmd%2FKernelshark&list_id=1090417&product=Tools&resolution=---
Thanks!
-- Steve
|