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Date: Tue, 3 Oct 2017 16:36:02 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>, linux-kernel@vger.kernel.org,
        acme@redhat.com, kirill.shutemov@linux.intel.com,
        Borislav Petkov <bp@alien8.de>, rric@kernel.org
Subject: Re: [RFC PATCH 06/17] perf: Add buffers to the detached events
Message-ID: <20171003143602.hg2rbwne4e22g46h@hirez.programming.kicks-ass.net>
References: <20170905133026.13689-1-alexander.shishkin@linux.intel.com>
 <20170905133026.13689-7-alexander.shishkin@linux.intel.com>
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On Tue, Sep 05, 2017 at 04:30:15PM +0300, Alexander Shishkin wrote:
> @@ -415,6 +416,8 @@ struct perf_event_attr {
>  	__u32	aux_watermark;
>  	__u16	sample_max_stack;
>  	__u16	__reserved_2;	/* align to __u64 */
> +	__u32	detached_nr_pages;
> +	__u32	detached_aux_nr_pages;
>  };

Not sure the naming makes sense; I don't see why this would be limited
to detached events. That is, what would stop someone from pre-allocating
buffers on 'regular' events if they wanted to?