From patchwork Mon Dec 21 11:30:42 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yao Qi X-Patchwork-Id: 10089 Received: (qmail 1148 invoked by alias); 21 Dec 2015 11:30:53 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Delivered-To: mailing list gdb-patches@sourceware.org Received: (qmail 1023 invoked by uid 89); 21 Dec 2015 11:30:53 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.3 required=5.0 tests=AWL, BAYES_00, FREEMAIL_FROM, RCVD_IN_DNSWL_LOW, SPF_PASS autolearn=ham version=3.3.2 spammy=003, sk:request, Hx-languages-length:1623, control-c X-HELO: mail-pa0-f54.google.com Received: from mail-pa0-f54.google.com (HELO mail-pa0-f54.google.com) (209.85.220.54) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES128-GCM-SHA256 encrypted) ESMTPS; Mon, 21 Dec 2015 11:30:51 +0000 Received: by mail-pa0-f54.google.com with SMTP id jx14so70361229pad.2 for ; Mon, 21 Dec 2015 03:30:51 -0800 (PST) X-Received: by 10.66.101.36 with SMTP id fd4mr26713384pab.76.1450697450179; Mon, 21 Dec 2015 03:30:50 -0800 (PST) Received: from E107787-LIN.cambridge.arm.com (gcc1-power7.osuosl.org. [140.211.15.137]) by smtp.gmail.com with ESMTPSA id zo4sm26286984pac.28.2015.12.21.03.30.49 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 21 Dec 2015 03:30:49 -0800 (PST) From: Yao Qi X-Google-Original-From: Yao Qi To: gdb-patches@sourceware.org Subject: [RFC 1/2] Check input interrupt first when reading packet Date: Mon, 21 Dec 2015 11:30:42 +0000 Message-Id: <1450697443-29067-2-git-send-email-yao.qi@linaro.org> In-Reply-To: <1450697443-29067-1-git-send-email-yao.qi@linaro.org> References: <1450697443-29067-1-git-send-email-yao.qi@linaro.org> X-IsSubscribed: yes Hi, I see timeout in one of several runs of random-signal.exp like this, $ (set -e; while true; do make check RUNTESTFLAGS="--target_board=native-gdbserver random-signal.exp"; done) In about every five runs, we can see a fail, PASS: gdb.base/random-signal.exp: continue ^CFAIL: gdb.base/random-signal.exp: stop with control-c (timeout) after some investigation, I find '\003' may be discarded by GDBserver when it is expecting '$'. In GDB side, both normal packets and '\003' are sent via function send, but GDBserver may receive them in one time, that is to say, in the GDBserver's receive buffer, '\003' may appear before or after normal packet. However, current GDBserver doesn't handle this case. With this patch applied, I don't see this fail in multiple runs. Although there is still another timeout fail, that is a different problem, the next patch will fix it. gdb/gdbserver: 2015-12-21 Yao Qi * remote-utils.c (getpkt): If c is '\003', call target hook request_interrupt. --- gdb/gdbserver/remote-utils.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/gdb/gdbserver/remote-utils.c b/gdb/gdbserver/remote-utils.c index 05e3d63..8bb5b13 100644 --- a/gdb/gdbserver/remote-utils.c +++ b/gdb/gdbserver/remote-utils.c @@ -959,6 +959,15 @@ getpkt (char *buf) while (1) { c = readchar (); + + /* The '\003' may appear before or after each packet, so + check for an input interrupt. */ + if (c == '\003') + { + (*the_target->request_interrupt) (); + c = readchar (); + } + if (c == '$') break; if (remote_debug)