linux-kernel - Re: [PATCH v4 1/6] perf tools: Derive trigger class from auxtrace

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 18 Apr 2016 22:20:23 +0800
From:	"Wangnan (F)" <wangnan0@...wei.com>
To:	Jiri Olsa <jolsa@...hat.com>
CC:	<acme@...nel.org>, <linux-kernel@...r.kernel.org>,
	<pi3orama@....com>, Adrian Hunter <adrian.hunter@...el.com>,
	He Kuang <hekuang@...wei.com>, Jiri Olsa <jolsa@...nel.org>,
	Masami Hiramatsu <mhiramat@...nel.org>,
	Namhyung Kim <namhyung@...nel.org>,
	Zefan Li <lizefan@...wei.com>
Subject: Re: [PATCH v4 1/6] perf tools: Derive trigger class from
 auxtrace_snapshot



On 2016/4/18 21:45, Jiri Olsa wrote:
> On Mon, Apr 18, 2016 at 06:32:08AM +0000, Wang Nan wrote:
>> Use 'trigger' to model operations which need to be executed when
>> an event (a signal, for example) is observed.
>>
>> States and transits:
>>
>>   OFF--(on)--> READY --(toggle)--> TOGGLED --(process)--> PROCESSING
>>                  ^                    |                      |
>>                  |                    |                      |
>>                  |                 (ready)                (ready)
>>                  |                    |                      |
>>                   \__________________/______________________/
>>
>> is_toggled and is_ready are two key functions to query the state of
>> a trigger. is_toggled means the event already happen; is_ready means the
>> trigger is waiting for the event.
>>
>> 'PROCESSING' represents a state the event happens and be observed, and
>> the processing is on the way so can't accept a new event immediately.
> hum, I must be missing something.. but I dont see how you're
> using this state except for smal window within:
>
>                  if (auxtrace_snapshot_is_toggled()) {
>   ->                     auxtrace_snapshot_process();
>                          if (!auxtrace_snapshot_is_error())
>   ->                              record__read_auxtrace_snapshot(rec);
>
> but no other place queries or depends on this state

Right.

Since we are creating a new class, I think we can make code simpler by 
merging
all state variables into trigger.

Without this state we must keep 'auxtrace_record__snapshot_started'.

I think merging it into trigger class makes the whole program a little
bit simpler. Or do you think keeping trigger class simpler whould be better?

Thank you.