linux-kernel - Re: [PATCH] perf record: Add snapshot mode support for perf's regular events

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]

Message-ID: <565582E0.7070202@huawei.com>
Date:	Wed, 25 Nov 2015 17:44:00 +0800
From:	"Wangnan (F)" <wangnan0@...wei.com>
To:	Peter Zijlstra <peterz@...radead.org>,
	Yunlong Song <yunlong.song@...wei.com>
CC:	<paulus@...ba.org>, <mingo@...hat.com>, <acme@...nel.org>,
	<linux-kernel@...r.kernel.org>, <namhyung@...nel.org>,
	<ast@...nel.org>, <masami.hiramatsu.pt@...achi.com>,
	<kan.liang@...el.com>, <adrian.hunter@...el.com>,
	<jolsa@...nel.org>, <dsahern@...il.com>, <bp@...en8.de>,
	<jean.pihet@...aro.org>, <rric@...nel.org>, <xiakaixu@...wei.com>,
	<hekuang@...wei.com>
Subject: Re: [PATCH] perf record: Add snapshot mode support for perf's regular
 events



On 2015/11/25 17:27, Peter Zijlstra wrote:
> On Tue, Nov 24, 2015 at 10:00:31PM +0800, Yunlong Song wrote:
>> In our patch, we create and maintain a user space ring buffer to store
>> perf's tracing info, instead of directly writing to perf.data file as
>> before. In snapshot mode, only a SIGUSR2 signal can trigger perf to dump
>> the tracing info currently stored in the user space ring buffer to
>> perf.data file.
> I would very much like to first fix the perf overwrite mode: see
> lkml.kernel.org/r/20151023151205.GW11639@...ns.programming.kicks-ass.net

I think they can be done in parallel. We can first do something with
tracking events and perf's output file, and wait for kernel level
overwrite mode fixed, then decide whether to implement perf's own
ringbuffer.

Thank you.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/