From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-5.8 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham autolearn_force=no version=3.4.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id AFE017D048 for ; Tue, 10 Jul 2018 15:25:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933475AbeGJPZd (ORCPT ); Tue, 10 Jul 2018 11:25:33 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:58966 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S933374AbeGJPZc (ORCPT ); Tue, 10 Jul 2018 11:25:32 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 646F081A4EAF; Tue, 10 Jul 2018 15:25:31 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.34.27.30]) by smtp.corp.redhat.com (Postfix) with SMTP id DED3A2156889; Tue, 10 Jul 2018 15:25:27 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Tue, 10 Jul 2018 17:25:31 +0200 (CEST) Date: Tue, 10 Jul 2018 17:25:27 +0200 From: Oleg Nesterov To: Ravi Bangoria Cc: srikar@linux.vnet.ibm.com, rostedt@goodmis.org, mhiramat@kernel.org, peterz@infradead.org, mingo@redhat.com, acme@kernel.org, alexander.shishkin@linux.intel.com, jolsa@redhat.com, namhyung@kernel.org, linux-kernel@vger.kernel.org, corbet@lwn.net, linux-doc@vger.kernel.org, ananth@linux.vnet.ibm.com, alexis.berlemont@gmail.com, naveen.n.rao@linux.vnet.ibm.com, linux-arm-kernel@lists.infradead.org, linux-mips@linux-mips.org, linux@armlinux.org.uk, ralf@linux-mips.org, paul.burton@mips.com Subject: Re: [PATCH v5 06/10] Uprobes: Support SDT markers having reference count (semaphore) Message-ID: <20180710152527.GA3616@redhat.com> References: <20180628052209.13056-1-ravi.bangoria@linux.ibm.com> <20180628052209.13056-7-ravi.bangoria@linux.ibm.com> <20180701210935.GA14404@redhat.com> <0c543791-f3b7-5a4b-f002-e1c76bb430c0@linux.ibm.com> <20180702180156.GA31400@redhat.com> <20180703163645.GA23144@redhat.com> <20180703172543.GC23144@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.8]); Tue, 10 Jul 2018 15:25:31 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.8]); Tue, 10 Jul 2018 15:25:31 +0000 (UTC) for IP:'10.11.54.6' DOMAIN:'int-mx06.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'oleg@redhat.com' RCPT:'' Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org Hi Ravi, On 07/04, Ravi Bangoria wrote: > > > Now I understand what did you mean by "for each consumer". So if we move this logic > > into install/remove_breakpoint as I tried to suggest, we will also need another error > > code for the case when verify_opcode() returns false. > > Ok so if we can use verify_opcode() inside install_breakpoint(), we can probably > move implementation logic in install/remove_breakpoint(). Let me explore that more. No, sorry for confusion, I meant another thing... But please forget. If we rely on verify_opcode() I no longer think it would be more clean to move this logic into install/remove_breakpoint. However, I still think it would be better to avoid uprobe exporting and modifying set_swbp/set_orig_insn. May be we can simply kill both set_swbp() and set_orig_insn(), I'll re-check... Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html