From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 68627 invoked by alias); 7 Jun 2017 12:23:37 -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 68613 invoked by uid 89); 7 Jun 2017 12:23:35 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-15.9 required=5.0 tests=BAYES_00,GIT_PATCH_1,GIT_PATCH_2,GIT_PATCH_3,KAM_LAZY_DOMAIN_SECURITY,SPF_HELO_PASS,T_RP_MATCHES_RCVD autolearn=ham version=3.3.2 spammy= 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; Wed, 07 Jun 2017 12:23:33 +0000 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 7C84580C02 for ; Wed, 7 Jun 2017 12:23:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 7C84580C02 Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=palves@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 7C84580C02 Received: from [127.0.0.1] (ovpn04.gateway.prod.ext.ams2.redhat.com [10.39.146.4]) by smtp.corp.redhat.com (Postfix) with ESMTP id 20E127D517; Wed, 7 Jun 2017 12:23:33 +0000 (UTC) Subject: Re: [PATCH v6 3/4] Share fork_inferior et al with gdbserver To: Sergio Durigan Junior References: <1482464361-4068-1-git-send-email-sergiodj@redhat.com> <20170504052954.16936-1-sergiodj@redhat.com> <20170504052954.16936-4-sergiodj@redhat.com> <0e95d746-9293-3301-15ed-84d6c4280116@redhat.com> <87poep8zdg.fsf@redhat.com> Cc: GDB Patches From: Pedro Alves Message-ID: Date: Wed, 07 Jun 2017 12:23:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-SW-Source: 2017-06/txt/msg00169.txt.bz2 On 06/07/2017 11:15 AM, Pedro Alves wrote: > On 05/31/2017 04:43 AM, Sergio Durigan Junior wrote: >> >>>>>> index 4ea7913..8aa85db 100644 >>>>>> --- a/gdb/gdbserver/configure.ac >>>>>> +++ b/gdb/gdbserver/configure.ac >>>>>> @@ -462,7 +462,9 @@ esac], >>>>>> >>>>>> if $want_ipa ; then >>>>>> if $have_ipa ; then >>>>>> - IPA_DEPFILES="$ipa_obj" >>>>>> + # Needed because safe_strerror's definition is host-dependent >>>> >>>> Why do we end up needing safe_strerror in the IPA in the first place? >> This is needed because I moved the definition of >> trace_start_error_with_name from the old gdb/fork-child.c to >> common/common-utils.c. This function which uses safe_strerror, and >> common/common-utils.c is compiled by IPA. >> >> An option would be to keep these trace_start_error.* functions in >> nat/fork-inferior.c, but I think it is more logical to keep them on >> common-utils.c. > > I'd rather not add them to the IPA. The least unnecessary code > is included in that library the better, because it is injected > into the target process. So keeping them in fork-inferior.c > sounds better. > I tried it against v7, and that works. The think to keep in mind is that these trace_start_error functions are only called from the fork child, so they're very much fork-inferior.c related. >>>> >>>>>> -#if defined(__UCLIBC__) && defined(HAS_NOMMU) >>>>>> - pid = vfork (); >>>> >>>> Does fork_inferior end up always using vfork on no-MMU >>>> ports somehow? >> Sorry, I am not sure. How would I go about finding that? > > I'm not sure either. configure.ac for anything fork related? > Look at git blame history around those lines, see what other > bits were touched at the same time? gdbserver clearly cares about > being built for no-MMU ports, so the new code must too. We can't > just delete that support without an alternative. I think we just need to add the HAVE_MMU etc. check around vfork in fork-inferior.c. > >> Now, something that came up while I was testing things with mingw here. >> gdb/gdbserver/server.c now calls startup_inferior (define in >> nat/fork-inferior.c) directly, instead of doing things on its own. This >> is one of the goals of this series, but for targets that don't compile >> fork-inferior.c (like Windows) this is an obvious problem. So here's >> what I'm doing for the new version of the series: I'll move >> startup_inferior to common/ (probably common/common-fork-inferior.c or >> some such), so that all targets can have access to it (it's >> target-agnostic anyway). If you have any comments about this, please >> let me know. > > This sounds quite contorted, but I'll take a better look at it in v7. I think that we just need to create a gdbserver/fork-child.c that is very much like gdb's own gdb/fork-child.c ends up looking like, and then only building fork-child.o on hosts that also build nat/fork-inferior.o. We can get rid of the function pointer parameter this way. I'll send you a patch on top of v7 in reply to v7, to show what I mean. Thanks, Pedro Alves