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Date: Fri, 27 Dec 2013 14:49:02 -0300
From: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
To: David Ahern <dsahern@gmail.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
        Ingo Molnar <mingo@kernel.org>,
        Srikar Dronamraju <srikar@linux.vnet.ibm.com>,
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        "David A. Long" <dave.long@linaro.org>, systemtap@sourceware.org,
        yrl.pp-manager.tt@hitachi.com, Namhyung Kim <namhyung@kernel.org>
Subject: Re: [PATCH -tip v2 1/2] [CLEANUP] perf-probe: Expand given path to
 absolute path
Message-ID: <20131227174902.GA13381@ghostprotocols.net>
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Em Fri, Dec 27, 2013 at 09:20:11AM -0500, David Ahern escreveu:
> On 12/27/13, 1:14 AM, Masami Hiramatsu wrote:
> >Nowhere, since there is no terminal code for user
> >command interface.

> >Those memories are released when the program terminated.
> >I think it is just a waste of the time to free the memory
> >pieces which are not used(and allocated) repeatedly.
> >Or, is there any chance to call this part directly from
> >other command?

There is always the chance of parts of a tool to be librarized, I think
the rule is: allocator -> lifetime -> destructor, explicit.

We may want to explicitely disable some big destructor call (or lots of
destructors, like symbols + hists, etc) because it may make exit time to
be overly long, but at least we'll know what destructors to call when
such code gets librarized.

- Arnaldo

> Most of the functionality has a destructor to clean up memory
> allocations. probe code needs to follow suit.
> 
> e.g, from builtin-record.c:
> 
>     err = __cmd_record(&record, argc, argv);
> 
>     perf_evlist__munmap(evsel_list);
>     perf_evlist__close(evsel_list);
> out_free_fd:
>     perf_evlist__delete_maps(evsel_list);
> out_symbol_exit:
>     symbol__exit();
> 
> and __cmd_record ends by cleaning up the session struct.
> 
> David