trace-cmd profile is not working

[Jerome Marchand <jmarchan@redhat.com>]

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,
Jerome