linux-kernel - Re: [PATCH v5 4/8] perf record: Introduce rec->overwrite

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:	Wed, 25 May 2016 21:47:37 +0800
From:	"Wangnan (F)" <wangnan0@...wei.com>
To:	<acme@...nel.org>
CC:	<pi3orama@....com>, <linux-kernel@...r.kernel.org>,
	He Kuang <hekuang@...wei.com>,
	Arnaldo Carvalho de Melo <acme@...hat.com>,
	Jiri Olsa <jolsa@...nel.org>,
	Masami Hiramatsu <masami.hiramatsu.pt@...achi.com>,
	Namhyung Kim <namhyung@...nel.org>,
	Zefan Li <lizefan@...wei.com>
Subject: Re: [PATCH v5 4/8] perf record: Introduce rec->overwrite_evlist for
 overwritable events


On 2016/5/25 18:16, Wangnan (F) wrote:
>
>
> On 2016/5/25 13:03, Wang Nan wrote:
>> Create an auxiliary evlist for overwritable events.
>>
>> Before mmap, build this evlist and set 'overwrite' and 'backward'
>> attribute. Since perf_evlist__mmap_ex() only maps events when
>> evsel->overwrite matches evlist's corresponding attributes, with
>> these two evlists an event goes to either rec->evlist or
>> rec->overwrite_evlist.
>>
>> Signed-off-by: Wang Nan <wangnan0@...wei.com>
>> Cc: He Kuang <hekuang@...wei.com>
>> Cc: Arnaldo Carvalho de Melo <acme@...hat.com>
>> Cc: Jiri Olsa <jolsa@...nel.org>
>> Cc: Masami Hiramatsu <masami.hiramatsu.pt@...achi.com>
>> Cc: Namhyung Kim <namhyung@...nel.org>
>> Cc: Zefan Li <lizefan@...wei.com>
>> Cc: pi3orama@....com
>> ---
>>   tools/perf/builtin-record.c | 138 
>> ++++++++++++++++++++++++++++++++++++--------
>>   1 file changed, 114 insertions(+), 24 deletions(-)
>>
>
> [SNIP]
>
>> @@ -941,7 +1026,10 @@ static int __cmd_record(struct record *rec, int 
>> argc, const char **argv)
>>                   err = 0;
>>               waking++;
>>   -            if (perf_evlist__filter_pollfd(rec->evlist, POLLERR | 
>> POLLHUP) == 0)
>> +            active_evts = perf_evlist__filter_pollfd(rec->evlist, 
>> POLLERR | POLLHUP);
>> +            active_evts += 
>> perf_evlist__filter_pollfd(rec->overwrite_evlist, POLLERR | POLLHUP);
>
> Sorry, before calling filter here should check if 
> rec->overwrite_evlist is not NULL.
> I'll resend this patch with this problem fixed soon.

Please ignore the full v5 series and see v6 instead. The final two patches
(9/10 and 10/10) in v6 solve the problem.

Thank you.