From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr1-f47.google.com (mail-wr1-f47.google.com [209.85.221.47]) by sourceware.org (Postfix) with ESMTPS id 6A19938418AC for ; Mon, 20 Jun 2022 22:55:02 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 6A19938418AC 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-f47.google.com with SMTP id w17so16479718wrg.7 for ; Mon, 20 Jun 2022 15:55:02 -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=OXRKvPT2YwBi5Vi8EhBWgFfASZb4KuqSO13FzjZH5ek=; b=ZGjsrmFY3PaLjTM8CWR25BGFI/fKjDPChgZW0GRSNmWNXek9Mj6U1xcCifck+ky3Kj isYpOV7OdL2gLYf6JEVEAU6KRXDz4oqtu271tVi2wUWqViPEP9BH9Y3mDQ9ybYQ1QVDC KB/KQw9EdJ0DrOj4tQH3E6WtB3E2NlOcPvinAfuzXdbEywMCvT68/LLhZswxaAF9qj4a T4UtrH+CpzMIiCCg0amZvM4pawydH3GkvEu3XdLVcyoDmLGMq6tLf2PgKkvUMoJJ3zCc VOqYEgA6a4LTVD31MhJBD6XyVFadVhWQTKQZVAlFgQ0OHU1AKKk6V9oVETJwGa4KWCgZ mSEg== X-Gm-Message-State: AJIora9O6szAIDv5zArmzimsAUPtO0o7Yk7wIKMVhPyE6m/zgbXKVlbv hjv+uAAFmwlqvnyUGEo2Nq6/WKmRQGs= X-Google-Smtp-Source: AGRyM1tk2Pwwvj7qxsCTRPF6E48qwU9YNj+FdWetbmoSRqojgS4P90e7/3x7KHcyMR8XaA8uyPz8lw== X-Received: by 2002:a5d:64aa:0:b0:218:4287:3c98 with SMTP id m10-20020a5d64aa000000b0021842873c98mr24713694wrp.453.1655765701400; Mon, 20 Jun 2022 15:55:01 -0700 (PDT) Received: from localhost ([2001:8a0:f924:2600:209d:85e2:409e:8726]) by smtp.gmail.com with ESMTPSA id v1-20020a5d6781000000b0021b93b29cacsm2924744wru.99.2022.06.20.15.55.00 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 20 Jun 2022 15:55:00 -0700 (PDT) From: Pedro Alves To: gdb-patches@sourceware.org Subject: [PATCH 18/25] gdbserver: Queue no-resumed event after thread exit Date: Mon, 20 Jun 2022 23:54:12 +0100 Message-Id: <20220620225419.382221-19-pedro@palves.net> X-Mailer: git-send-email 2.36.0 In-Reply-To: <20220620225419.382221-1-pedro@palves.net> References: <20220620225419.382221-1-pedro@palves.net> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-9.8 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: Mon, 20 Jun 2022 22:55:04 -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 8154d8088c1..50aa369ccf0 100644 --- a/gdbserver/linux-low.cc +++ b/gdbserver/linux-low.cc @@ -2960,7 +2960,6 @@ 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 ()); @@ -2974,23 +2973,7 @@ 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); @@ -3001,7 +2984,7 @@ 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); @@ -6169,6 +6152,32 @@ 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 fc64a442ab4..ea990ebe1d3 100644 --- a/gdbserver/server.cc +++ b/gdbserver/server.cc @@ -4740,7 +4740,17 @@ 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