linux-kernel - Re: [PATCH 01/14] perf/x86: Introduce PERF_RECORD

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, 23 Nov 2016 21:13:17 +0100
From:   Peter Zijlstra <peterz@...radead.org>
To:     kan.liang@...el.com
Cc:     mingo@...hat.com, acme@...nel.org, linux-kernel@...r.kernel.org,
        alexander.shishkin@...ux.intel.com, tglx@...utronix.de,
        namhyung@...nel.org, jolsa@...nel.org, adrian.hunter@...el.com,
        wangnan0@...wei.com, mark.rutland@....com, andi@...stfloor.org
Subject: Re: [PATCH 01/14] perf/x86: Introduce PERF_RECORD_OVERHEAD

On Wed, Nov 23, 2016 at 04:44:39AM -0500, kan.liang@...el.com wrote:
> +/*
> + * single overhead record layout:
> + *
> + * 	 cpu: The cpu which overhead occues

This is duplicate information, its already present in sample_id when
PERF_SAMPLE_CPU, and without that we don't care.

> + * 	  nr: Times of overhead happens.
> + * 	      E.g. for NMI, nr == times of NMI handler are called.
> + * 	time: Total overhead cost(ns)
> + */
> +struct perf_overhead_entry {
> +	__u32	cpu;
> +	__u64	nr;
> +	__u64	time;
> +};