linux-kernel - Re: [PATCH] perf: make perf.data more self-descriptive (v8)

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, 5 Dec 2011 14:23:40 +0100
From:	Robert Richter <robert.richter@....com>
To:	Stephane Eranian <eranian@...gle.com>
CC:	Frederic Weisbecker <fweisbec@...il.com>,
	"acme@...hat.com" <acme@...stprotocols.net>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"peterz@...radead.org" <peterz@...radead.org>,
	"dsahern@...il.com" <dsahern@...il.com>,
	"ak@...ux.intel.com" <ak@...ux.intel.com>,
	"mingo@...e.hu" <mingo@...e.hu>
Subject: Re: [PATCH] perf: make perf.data more self-descriptive (v8)

On 01.12.11 09:53:10, Stephane Eranian wrote:
> On Thu, Dec 1, 2011 at 7:15 AM, Robert Richter <robert.richter@....com> wrote:
> > I am asking this because I want to change code in a way that treats
> > all features the same, that is just to disable the feature bit on
> > failure and then continue anyway.
> >
> You need to make sure that disabling the bit is enough to still get a consistent
> file, i.e., want to undo the effect of writing the feature to the
> file. In the case
> of the meta-data features I added that was easy simply lseek() back to
> the position
> before the call. Would that be the case with TRACE_INFO?

It should be. All features can be parsed independently. Offset and
size of a feature's data block is stored in struct perf_file_section
right after the data block of perf.data (see perf_session__write_
header()). Thus, if a feature does not exist then other features can
be processed anyway.

Thanks,

-Robert

-- 
Advanced Micro Devices, Inc.
Operating System Research Center

--
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/