linux-kernel - Re: [PATCH 1/3] arm/pmu: Reject groups spanning multiple hardware PMUs

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: <20150310112723.GY2896@worktop.programming.kicks-ass.net>
Date:	Tue, 10 Mar 2015 12:27:23 +0100
From:	Peter Zijlstra <peterz@...radead.org>
To:	"Suzuki K. Poulose" <suzuki.poulose@....com>
Cc:	will.deacon@....com, linux@....linux.org.uk, acme@...nel.org,
	linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
	punit.agrawal@....com, pawel.moll@....com,
	Mark Rutland <mark.rutland@....com>
Subject: Re: [PATCH 1/3] arm/pmu: Reject groups spanning multiple hardware
 PMUs

On Mon, Mar 09, 2015 at 12:46:30PM +0000, Suzuki K. Poulose wrote:
> From: "Suzuki K. Poulose" <suzuki.poulose@....com>
> 
> Don't allow grouping hardware events from different PMUs
>  (eg. CCI + CPU).

Uhm, how does this work? If we have multiple hardware PMUs we'll stop
scheduling events after the first failed event schedule. This can leave
one of the PMUs severely under utilized.
--
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/