From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752311AbcHAJBs (ORCPT ); Mon, 1 Aug 2016 05:01:48 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:61711 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752267AbcHAJBk (ORCPT ); Mon, 1 Aug 2016 05:01:40 -0400 X-IBM-Helo: d03dlp03.boulder.ibm.com X-IBM-MailFrom: ravi.bangoria@linux.vnet.ibm.com Subject: Re: [RFC] perf uprobe: Skip prologue if program compiled without optimization To: Masami Hiramatsu References: <1469716311-18343-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com> <20160730120408.1165064035943d452bb377ee@kernel.org> Cc: linux-kernel@vger.kernel.org, peterz@infradead.org, mingo@redhat.com, acme@kernel.org, alexander.shishkin@linux.intel.com, wangnan0@huawei.com, hemant@linux.vnet.ibm.com From: Ravi Bangoria Date: Mon, 1 Aug 2016 14:31:25 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <20160730120408.1165064035943d452bb377ee@kernel.org> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16080109-0004-0000-0000-00001008CE00 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00005543; HX=3.00000240; KW=3.00000007; PH=3.00000004; SC=3.00000177; SDB=6.00738378; UDB=6.00347011; IPR=6.00510975; BA=6.00004634; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00012119; XFM=3.00000011; UTC=2016-08-01 09:01:38 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 16080109-0005-0000-0000-000077981A0B Message-Id: <579F0FE5.8080106@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-08-01_03:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1604210000 definitions=main-1608010098 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Saturday 30 July 2016 08:34 AM, Masami Hiramatsu wrote: > On Thu, 28 Jul 2016 20:01:51 +0530 > Ravi Bangoria wrote: > >> Function prologue prepares stack and registers before executing function >> logic. When target program is compiled without optimization, function >> parameter information is only valid after prologue. When we probe entrypc >> of the function, and try to record function parameter, it contains >> garbage value. > Right! :) Thanks Masami for review. I've sent patch with changes you suggested. Please review it. -Ravi