Recently 'perf <tool> -h' was made aware of arguments and would show
just the help for the arguments specified, but that required a strict
form, i.e.:
$ perf -h --tui
worked, but:
$ perf -h tui
didn't.
Make it support both cases and also look at the option help when neither
matches, so that he following examples works:
$ perf report -h interface
Usage: perf report [<options>]
--gtk Use the GTK2 interface
--stdio Use the stdio interface
--tui Use the TUI interface
$ perf report -h stack
Usage: perf report [<options>]
-g, --call-graph <print_type,threshold[,print_limit],order,
sort_key[,branch]>
Display call graph (stack chain/backtrace):
print_type: call graph printing style (graph|flat|fractal|none)
threshold: minimum call graph inclusion threshold (<percent>)
print_limit: maximum number of call graph entry (<number>)
order: call graph order (caller|callee)
sort_key: call graph sort key (function|address)
branch: include last branch info to call graph (branch)
Default: graph,0.5,caller,function
--max-stack <n> Set the maximum stack depth when parsing the
callchain, anything beyond the specified depth
will be ignored. Default: 127
$
Suggested-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Chandler Carruth <chandlerc@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-xzqvamzqv3cv0p6w3inhols3@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
f4efcce33d