From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr1-f45.google.com (mail-wr1-f45.google.com [209.85.221.45]) by sourceware.org (Postfix) with ESMTPS id 9EE5B3899B58 for ; Wed, 13 Jul 2022 22:25:20 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 9EE5B3899B58 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=palves.net Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-wr1-f45.google.com with SMTP id r14so53159wrg.1 for ; Wed, 13 Jul 2022 15:25:20 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=f/ZtekMGOv1Ebdxfa1kjDVF5ivxtggdOp5hGbfiu0mg=; b=HErjb1T7Aet4lPQQZNSVuXOTc5sI4ZYbPkIMEXp04EZ7CSSO2RhBAcBJ44U9WdI8+h iAjX5J+QCO/EkU3qK2pqgJo1cjXNkwTv58FJWDE6JE7SnpPpgLHoDML8G9lsTKDrKb6/ qlpFZTCLY8M9MpTBl87MPbOu9RiDJ+f7kaw/6tQHdR+3CFIIeFFGIbQyMaoaWW2Klw/o d6hkv0h/gTYIk0I6xF4Y/6RI/OfiwZaiZTvqDdh6NTjvQCElj/XrG6924+pPGv8m5UBw jtVEaWtifGPsxMj2TcfY3XnS/7xeSGE8F7dvLkMwrT3LGkDYHH2/Y8yx3so/Ld9K3gew H/gg== X-Gm-Message-State: AJIora9m2u/kPVO9Y0374mj7PnNxaTvsdoRaCc54KF9ky7MbbNlBxaKt s3LuYParXZGPwrCq/3EwP+OhPIxXBjM= X-Google-Smtp-Source: AGRyM1sdUrhHCam61NPqlQSkKxGFKz3KeibpBjvaDWT/ic6w80hdczLxjdpgOv2DgBFuNk72uNXCgg== X-Received: by 2002:adf:dd52:0:b0:21d:941a:3ade with SMTP id u18-20020adfdd52000000b0021d941a3ademr5249976wrm.10.1657751119446; Wed, 13 Jul 2022 15:25:19 -0700 (PDT) Received: from localhost ([2001:8a0:f924:2600:209d:85e2:409e:8726]) by smtp.gmail.com with ESMTPSA id f2-20020a1cc902000000b003a2e655f2e6sm3339852wmb.21.2022.07.13.15.25.17 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 13 Jul 2022 15:25:18 -0700 (PDT) From: Pedro Alves To: gdb-patches@sourceware.org Subject: [PATCH v2 20/29] gdbserver: Queue no-resumed event after thread exit Date: Wed, 13 Jul 2022 23:24:24 +0100 Message-Id: <20220713222433.374898-21-pedro@palves.net> X-Mailer: git-send-email 2.36.0 In-Reply-To: <20220713222433.374898-1-pedro@palves.net> References: <20220713222433.374898-1-pedro@palves.net> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-9.9 required=5.0 tests=BAYES_00, FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM, GIT_PATCH_0, HEADER_FROM_DIFFERENT_DOMAINS, KAM_DMARC_STATUS, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 13 Jul 2022 22:25:22 -0000 Normally, if the last thread resumed thread on the target exits, the server sends a no-resumed event to GDB. If however, GDB enables the GDB_TO_EXIT option on a thread, and, that thread exits, the server sends a thread exit event for that thread instead. In all-stop RSP mode, since events can only be forwarded to GDB one at a time, and the whole target stops whenever an event is reported, GDB resumes the target again after getting a THREAD_EXITED event, and then the server finally reports back a no-resumed event if/when appropriate. For non-stop RSP though, events are asynchronous, and if the server sends a thread-exit event for the last resumed thread, the no-resumed event is never sent. This patch makes sure that in non-stop mode, the server queues a no-resumed event after the thread-exit event if it was the last resumed thread that exited. Without this, we'd see failures in step-over-thread-exit testcases added later in the series, like so: continue Continuing. - No unwaited-for children left. - (gdb) PASS: gdb.threads/step-over-thread-exit.exp: displaced-stepping=off: non-stop=on: target-non-stop=on: schedlock=off: ns_stop_all=1: continue stops when thread exits + FAIL: gdb.threads/step-over-thread-exit.exp: displaced-stepping=off: non-stop=on: target-non-stop=on: schedlock=off: ns_stop_all=1: continue stops when thread exits (timeout) (and other similar ones) Change-Id: I927d78b30f88236dbd5634b051a716f72420e7c7 --- gdbserver/linux-low.cc | 47 +++++++++++++++++++++++++----------------- gdbserver/linux-low.h | 2 ++ gdbserver/server.cc | 12 ++++++++++- gdbserver/target.cc | 6 ++++++ gdbserver/target.h | 6 ++++++ 5 files changed, 53 insertions(+), 20 deletions(-) diff --git a/gdbserver/linux-low.cc b/gdbserver/linux-low.cc index 54ab0a7d8f5..9858e228675 100644 --- a/gdbserver/linux-low.cc +++ b/gdbserver/linux-low.cc @@ -2965,7 +2965,6 @@ linux_process_target::wait_1 (ptid_t ptid, target_waitstatus *ourstatus, int report_to_gdb; int trace_event; int in_step_range; - int any_resumed; threads_debug_printf ("[%s]", target_pid_to_str (ptid).c_str ()); @@ -2979,23 +2978,7 @@ linux_process_target::wait_1 (ptid_t ptid, target_waitstatus *ourstatus, in_step_range = 0; ourstatus->set_ignore (); - auto status_pending_p_any = [&] (thread_info *thread) - { - return status_pending_p_callback (thread, minus_one_ptid); - }; - - auto not_stopped = [&] (thread_info *thread) - { - return not_stopped_callback (thread, minus_one_ptid); - }; - - /* Find a resumed LWP, if any. */ - if (find_thread (status_pending_p_any) != NULL) - any_resumed = 1; - else if (find_thread (not_stopped) != NULL) - any_resumed = 1; - else - any_resumed = 0; + bool was_any_resumed = any_resumed (); if (step_over_bkpt == null_ptid) pid = wait_for_event (ptid, &w, options); @@ -3006,7 +2989,7 @@ linux_process_target::wait_1 (ptid_t ptid, target_waitstatus *ourstatus, pid = wait_for_event (step_over_bkpt, &w, options & ~WNOHANG); } - if (pid == 0 || (pid == -1 && !any_resumed)) + if (pid == 0 || (pid == -1 && !was_any_resumed)) { gdb_assert (target_options & TARGET_WNOHANG); @@ -6173,6 +6156,32 @@ linux_process_target::thread_stopped (thread_info *thread) return get_thread_lwp (thread)->stopped; } +bool +linux_process_target::any_resumed () +{ + bool any_resumed; + + auto status_pending_p_any = [&] (thread_info *thread) + { + return status_pending_p_callback (thread, minus_one_ptid); + }; + + auto not_stopped = [&] (thread_info *thread) + { + return not_stopped_callback (thread, minus_one_ptid); + }; + + /* Find a resumed LWP, if any. */ + if (find_thread (status_pending_p_any) != NULL) + any_resumed = 1; + else if (find_thread (not_stopped) != NULL) + any_resumed = 1; + else + any_resumed = 0; + + return any_resumed; +} + /* This exposes stop-all-threads functionality to other modules. */ void diff --git a/gdbserver/linux-low.h b/gdbserver/linux-low.h index 051a7196ef7..43c35009030 100644 --- a/gdbserver/linux-low.h +++ b/gdbserver/linux-low.h @@ -259,6 +259,8 @@ class linux_process_target : public process_stratum_target bool thread_stopped (thread_info *thread) override; + bool any_resumed () override; + void pause_all (bool freeze) override; void unpause_all (bool unfreeze) override; diff --git a/gdbserver/server.cc b/gdbserver/server.cc index 75a23e2c692..8b3e8bf884d 100644 --- a/gdbserver/server.cc +++ b/gdbserver/server.cc @@ -4742,7 +4742,17 @@ handle_target_event (int err, gdb_client_data client_data) } } else - push_stop_notification (cs.last_ptid, cs.last_status); + { + push_stop_notification (cs.last_ptid, cs.last_status); + + if (cs.last_status.kind () == TARGET_WAITKIND_THREAD_EXITED + && !target_any_resumed ()) + { + target_waitstatus ws; + ws.set_no_resumed (); + push_stop_notification (null_ptid, ws); + } + } } /* Be sure to not change the selected thread behind GDB's back. diff --git a/gdbserver/target.cc b/gdbserver/target.cc index ad32af0416e..96c0f49d2dd 100644 --- a/gdbserver/target.cc +++ b/gdbserver/target.cc @@ -612,6 +612,12 @@ process_stratum_target::thread_stopped (thread_info *thread) gdb_assert_not_reached ("target op thread_stopped not supported"); } +bool +process_stratum_target::any_resumed () +{ + return true; +} + bool process_stratum_target::supports_get_tib_address () { diff --git a/gdbserver/target.h b/gdbserver/target.h index 0aa7db49c18..dd8a55cf827 100644 --- a/gdbserver/target.h +++ b/gdbserver/target.h @@ -323,6 +323,9 @@ class process_stratum_target /* Return true if THREAD is known to be stopped now. */ virtual bool thread_stopped (thread_info *thread); + /* Return true if any thread is known to be resumed. */ + virtual bool any_resumed (); + /* Return true if the get_tib_address op is supported. */ virtual bool supports_get_tib_address (); @@ -683,6 +686,9 @@ target_read_btrace_conf (struct btrace_target_info *tinfo, #define target_supports_software_single_step() \ the_target->supports_software_single_step () +#define target_any_resumed() \ + the_target->any_resumed () + ptid_t mywait (ptid_t ptid, struct target_waitstatus *ourstatus, target_wait_flags options, int connected_wait); -- 2.36.0