Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754536Ab1CYGeM (ORCPT ); Fri, 25 Mar 2011 02:34:12 -0400 Received: from mga02.intel.com ([134.134.136.20]:24193 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753366Ab1CYGeL (ORCPT ); Fri, 25 Mar 2011 02:34:11 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.63,242,1299484800"; d="scan'208";a="618670632" Subject: Re: [PATCH v2 -tip] perf probe: Add fastpath to do lookup by function name From: Lin Ming To: Arnaldo Carvalho de Melo Cc: Masami Hiramatsu , Peter Zijlstra , Ingo Molnar , linux-kernel In-Reply-To: <20110325025752.GB11195@ghostprotocols.net> References: <1300981134-7333-1-git-send-email-ming.m.lin@intel.com> <4D8B0A13.8000008@hitachi.com> <1300974448.2283.17.camel@localhost> <1300975753.2283.20.camel@localhost> <4D8BEC71.1040404@hitachi.com> <20110325025752.GB11195@ghostprotocols.net> Content-Type: text/plain; charset="UTF-8" Date: Fri, 25 Mar 2011 14:33:45 +0800 Message-ID: <1301034825.2512.5.camel@hp6530s> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2811 Lines: 68 在 2011-03-25五的 10:57 +0800，Arnaldo Carvalho de Melo写道： > Em Fri, Mar 25, 2011 at 10:14:25AM +0900, Masami Hiramatsu escreveu: > > (2011/03/24 23:09), Lin Ming wrote: > > > v2 -> v1: > > > - Don't compare file names with cu_find_realpath(...), instead, compare them > > > with the name returned by dwarf_decl_file(sp_die) > > > > > > The vmlinux file may have thousands of CUs. > > > We can lookup function name from .debug_pubnames section > > > to avoid the slow loop on CUs. > > > > > > ./perf stat -r 10 -- ./perf probe -k /home/mlin/vmlinux \ > > > -s /home/mlin/linux-2.6 \ > > > --line csum_partial_copy_to_user > tmp.log > > > > > > before patch applied > > > ===================== > > > 364.535892 task-clock-msecs # 0.997 CPUs > > > 0 context-switches # 0.000 M/sec > > > 0 CPU-migrations # 0.000 M/sec > > > 29,993 page-faults # 0.082 M/sec > > > 865,862,109 cycles # 2375.245 M/sec > > > 1,255,259,630 instructions # 1.450 IPC > > > 252,400,884 branches # 692.390 M/sec > > > 3,429,376 branch-misses # 1.359 % > > > 1,386,990 cache-references # 3.805 M/sec > > > 687,188 cache-misses # 1.885 M/sec > > > > > > 0.365792170 seconds time elapsed > > > > > > after patch applied > > > ===================== > > > 89.896405 task-clock-msecs # 0.991 CPUs > > > 1 context-switches # 0.000 M/sec > > > 0 CPU-migrations # 0.000 M/sec > > > 10,145 page-faults # 0.113 M/sec > > > 214,553,875 cycles # 2386.679 M/sec > > > 226,915,559 instructions # 1.058 IPC > > > 44,536,614 branches # 495.422 M/sec > > > 613,074 branch-misses # 1.377 % > > > 860,787 cache-references # 9.575 M/sec > > > 442,380 cache-misses # 4.921 M/sec > > > > > > 0.090716032 seconds time elapsed > > > > Thanks! Looks very good :) > > > > Acked-by: Masami Hiramatsu > > Indeed, I'll try and process this one tomorrow, Except find_line_range, I just realized that the same optimization maybe added for find_probes. Thanks, Lin Ming > > Thanks a lot! > > - Arnaldo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/