Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756603AbcC2KBq (ORCPT ); Tue, 29 Mar 2016 06:01:46 -0400 Received: from hotel311.server4you.de ([85.25.146.15]:56311 "EHLO hotel311.server4you.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752005AbcC2KBn (ORCPT ); Tue, 29 Mar 2016 06:01:43 -0400 Subject: Re: [PATCH v16 22/23] tracing: Add hist trigger 'log2' modifier To: Tom Zanussi , rostedt@goodmis.org References: <7ff396b246c6a881f46b979735fddf05a0d6c71a.1457029949.git.tom.zanussi@linux.intel.com> Cc: masami.hiramatsu.pt@hitachi.com, namhyung@kernel.org, josh@joshtriplett.org, andi@firstfloor.org, mathieu.desnoyers@efficios.com, peterz@infradead.org, linux-kernel@vger.kernel.org From: Daniel Wagner Message-ID: <56FA5284.2050106@monom.org> Date: Tue, 29 Mar 2016 12:01:40 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: <7ff396b246c6a881f46b979735fddf05a0d6c71a.1457029949.git.tom.zanussi@linux.intel.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1088 Lines: 37 Hi, On 03/03/2016 07:55 PM, Tom Zanussi wrote: > When using '.log2' modifier, the output looks like: > > # echo 'hist:key=bytes_req.log2' > kmalloc/trigger > # cat kmalloc/hist > > { bytes_req: ~ 2^12 } hitcount: 1 > { bytes_req: ~ 2^11 } hitcount: 1 > { bytes_req: ~ 2^9 } hitcount: 2 > { bytes_req: ~ 2^6 } hitcount: 3 > { bytes_req: ~ 2^3 } hitcount: 13 > { bytes_req: ~ 2^5 } hitcount: 19 > { bytes_req: ~ 2^8 } hitcount: 49 > { bytes_req: ~ 2^7 } hitcount: 57 > { bytes_req: ~ 2^4 } hitcount: 74 I found a small inconsistency. My command line is echo 'hist:key=latency.log2:sort=latency' > /sys/kernel/debug/tracing/events/test/latency_complete/trigger When looking at the output of 'hist' you see that the 'sort=' is not what I provided. cat /sys/kernel/debug/tracing/events/test/latency_complete/hist # event histogram # # trigger info: hist:keys=latency.log2:vals=hitcount:sort=latency.log2:size=2048 [active] # # This is not terrible important. cheers, daniel