Date: Fri, 8 May 2015 13:05:47 +0200
From: Andi Kleen <andi@firstfloor.org>
To: Kan Liang <kan.liang@intel.com>
Cc: peterz@infradead.org, mingo@kernel.org, acme@infradead.org,
        eranian@google.com, andi@firstfloor.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH V8 3/8] perf, x86: handle multiple records in PEBS buffer
Message-ID: <20150508110547.GS2366@two.firstfloor.org>
References: <1430940834-8964-1-git-send-email-kan.liang@intel.com>
 <1430940834-8964-4-git-send-email-kan.liang@intel.com>
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> The first issue is that the 'status' field of the PEBS record is a copy
> of the GLOBAL_STATUS MSR at PEBS assist time. To see why this is a

I wanted to mention that Skylake has this issue fixed. The status
field in PEBS is now only the counter that triggered the PEBS record.

> The second issue is that the hardware will only emit one record for two
> or more counters if the event that triggers the assist is 'close'. The

If two events gets merged it is one or the other.

-Andi
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