Currently, commands which depend on 'parse_options_subcommand()' don't
show the usage string, and instead show '(null)'
$ ./perf sched
Usage: (null)
-D, --dump-raw-trace dump raw trace in ASCII
-f, --force don't complain, do it
-i, --input <file> input file name
-v, --verbose be more verbose (show symbol address, etc)
'parse_options_subcommand()' is generally expected to initialise the usage
string, with information in the passed 'subcommands[]' array
This behaviour was changed in:
230a7a71f9 ("libsubcmd: Fix parse-options memory leak")
Where the generated usage string is deallocated, and usage[0] string is
reassigned as NULL.
As discussed in [1], free the allocated usage string in the main
function itself, and don't reset usage string to NULL in
parse_options_subcommand
With this change, the behaviour is restored.
$ ./perf sched
Usage: perf sched [<options>] {record|latency|map|replay|script|timehist}
-D, --dump-raw-trace dump raw trace in ASCII
-f, --force don't complain, do it
-i, --input <file> input file name
-v, --verbose be more verbose (show symbol address, etc)
[1]: https://lore.kernel.org/linux-perf-users/htq5vhx6piet4nuq2mmhk7fs2bhfykv52dbppwxmo3s7du2odf@styd27tioc6e/
Fixes: 230a7a71f9 ("libsubcmd: Fix parse-options memory leak")
Suggested-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Aditya Gupta <adityag@linux.ibm.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Disha Goel <disgoel@linux.vnet.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240904061836.55873-2-adityag@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
1a5efc9e13