From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 11080 invoked by alias); 21 Mar 2014 17:22:23 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 11070 invoked by uid 89); 21 Mar 2014 17:22:23 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-4.1 required=5.0 tests=AWL,BAYES_00,SPF_HELO_PASS,SPF_PASS,T_RP_MATCHES_RCVD autolearn=ham version=3.3.2 X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Fri, 21 Mar 2014 17:22:22 +0000 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id s2LHMKhp013984 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Fri, 21 Mar 2014 13:22:20 -0400 Received: from host2.jankratochvil.net (ovpn-116-22.ams2.redhat.com [10.36.116.22]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id s2LHMGCx023991 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO); Fri, 21 Mar 2014 13:22:18 -0400 Date: Fri, 21 Mar 2014 17:22:00 -0000 From: Jan Kratochvil To: "Metzger, Markus T" Cc: "gdb-patches@sourceware.org" , "Pedro Alves (palves@redhat.com)" Subject: Re: [PATCH 2/2] btrace: avoid symbol lookup Message-ID: <20140321172215.GA15215@host2.jankratochvil.net> References: <1394182665-14164-1-git-send-email-markus.t.metzger@intel.com> <1394182665-14164-3-git-send-email-markus.t.metzger@intel.com> <20140310214252.GA3105@host2.jankratochvil.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-IsSubscribed: yes X-SW-Source: 2014-03/txt/msg00535.txt.bz2 On Tue, 11 Mar 2014 11:08:43 +0100, Metzger, Markus T wrote: > What's missing is a "fast fail", i.e. quickly determine that we won't find any > symbol for this PC. I won't be able to do this in a reasonable amount of time, > though, so I thought this patch is a compromise between functionality and > performance. I do not think providing incorrect behavior for performance reasons is a valid tradeoff. The right way would be to fix the DWARF lookups to be fast enough. But I no longer approve GDB patches so this is just my personal opinion. Jan