From patchwork Wed Oct 30 22:53:52 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Simon Marchi (Code Review)" X-Patchwork-Id: 35495 Received: (qmail 102440 invoked by alias); 30 Oct 2019 22:54:08 -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 102382 invoked by uid 89); 30 Oct 2019 22:54:08 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-21.1 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_SHORT autolearn=ham version=3.3.1 spammy=Hold, Actually X-HELO: mx1.osci.io Received: from polly.osci.io (HELO mx1.osci.io) (8.43.85.229) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Wed, 30 Oct 2019 22:54:05 +0000 Received: by mx1.osci.io (Postfix, from userid 994) id 0557D20468; Wed, 30 Oct 2019 18:54:04 -0400 (EDT) Received: from gnutoolchain-gerrit.osci.io (gnutoolchain-gerrit.osci.io [8.43.85.239]) by mx1.osci.io (Postfix) with ESMTP id DA18A20C08 for ; Wed, 30 Oct 2019 18:53:54 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by gnutoolchain-gerrit.osci.io (Postfix) with ESMTP id B27BB20AF6 for ; Wed, 30 Oct 2019 18:53:54 -0400 (EDT) X-Gerrit-PatchSet: 3 Date: Wed, 30 Oct 2019 18:53:52 -0400 From: "Tom Tromey (Code Review)" To: gdb-patches@sourceware.org Auto-Submitted: auto-generated X-Gerrit-MessageType: newpatchset Subject: [review v3] Introduce run_on_main_thread X-Gerrit-Change-Id: I16ef82f0564e9f8a524bdc64cb31df79a988ad9f X-Gerrit-Change-Number: 170 X-Gerrit-ChangeURL: X-Gerrit-Commit: 589c84aae29ef0c581d1a607a800f69beaaa1795 In-Reply-To: References: Reply-To: tromey@sourceware.org, gdb-patches@sourceware.org MIME-Version: 1.0 Content-Disposition: inline User-Agent: Gerrit/3.0.3-75-g9005159e5d Message-Id: <20191030225354.B27BB20AF6@gnutoolchain-gerrit.osci.io> Change URL: https://gnutoolchain-gerrit.osci.io/r/c/binutils-gdb/+/170 ...................................................................... Introduce run_on_main_thread This introduces a way for a callback to be run on the main thread. 2019-10-19 Tom Tromey * unittests/main-thread-selftests.c: New file. * Makefile.in (SUBDIR_UNITTESTS_SRCS): Add main-thread-selftests.c. * ser-event.h (run_on_main_thread): Declare. * ser-event.c (runnable_event, runnables, runnable_mutex): New globals. (run_events, run_on_main_thread, _initialize_ser_event): New functions. Change-Id: I16ef82f0564e9f8a524bdc64cb31df79a988ad9f --- M gdb/ChangeLog M gdb/Makefile.in M gdb/ser-event.c M gdb/ser-event.h A gdb/unittests/main-thread-selftests.c 5 files changed, 176 insertions(+), 0 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 90e4d27..4992399 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,5 +1,16 @@ 2019-10-19 Tom Tromey + * unittests/main-thread-selftests.c: New file. + * Makefile.in (SUBDIR_UNITTESTS_SRCS): Add + main-thread-selftests.c. + * ser-event.h (run_on_main_thread): Declare. + * ser-event.c (runnable_event, runnables, runnable_mutex): New + globals. + (run_events, run_on_main_thread, _initialize_ser_event): New + functions. + +2019-10-19 Tom Tromey + * main.c (setup_alternate_signal_stack): Remove. (captured_main_1): Use gdb::alternate_signal_stack. * gdbsupport/alt-stack.h: New file. diff --git a/gdb/Makefile.in b/gdb/Makefile.in index af42c8b..e3433b2 100644 --- a/gdb/Makefile.in +++ b/gdb/Makefile.in @@ -433,6 +433,7 @@ unittests/optional-selftests.c \ unittests/parse-connection-spec-selftests.c \ unittests/ptid-selftests.c \ + unittests/main-thread-selftests.c \ unittests/mkdir-recursive-selftests.c \ unittests/rsp-low-selftests.c \ unittests/scoped_fd-selftests.c \ diff --git a/gdb/ser-event.c b/gdb/ser-event.c index a65a186..029ced7 100644 --- a/gdb/ser-event.c +++ b/gdb/ser-event.c @@ -20,6 +20,10 @@ #include "ser-event.h" #include "serial.h" #include "gdbsupport/filestuff.h" +#if CXX_STD_THREAD +#include +#endif +#include "event-loop.h" /* On POSIX hosts, a serial_event is basically an abstraction for the classical self-pipe trick. @@ -217,3 +221,77 @@ ResetEvent (state->event); #endif } + + + +/* The serial event used when posting runnables. */ + +static struct serial_event *runnable_event; + +/* Runnables that have been posted. */ + +static std::vector> runnables; + +#if CXX_STD_THREAD + +/* Mutex to hold when handling runnable_event or runnables. */ + +static std::mutex runnable_mutex; + +#endif + +/* Run all the queued runnables. */ + +static void +run_events (int error, gdb_client_data client_data) +{ + std::vector> local; + + /* Hold the lock while changing the globals, but not while running + the runnables. */ + { +#if CXX_STD_THREAD + std::lock_guard lock (runnable_mutex); +#endif + + /* Clear the event fd. Do this before flushing the events list, + so that any new event post afterwards is sure to re-awaken the + event loop. */ + serial_event_clear (runnable_event); + + /* Move the vector in case running a runnable pushes a new + runnable. */ + local = std::move (runnables); + } + + for (auto &item : local) + { + try + { + item (); + } + catch (...) + { + /* Ignore exceptions in the callback. */ + } + } +} + +/* See ser-event.h. */ + +void +run_on_main_thread (std::function &&func) +{ +#if CXX_STD_THREAD + std::lock_guard lock (runnable_mutex); +#endif + runnables.emplace_back (std::move (func)); + serial_event_set (runnable_event); +} + +void +_initialize_ser_event () +{ + runnable_event = make_serial_event (); + add_file_handler (serial_event_fd (runnable_event), run_events, nullptr); +} diff --git a/gdb/ser-event.h b/gdb/ser-event.h index 1373485..61a84f9 100644 --- a/gdb/ser-event.h +++ b/gdb/ser-event.h @@ -19,6 +19,8 @@ #ifndef SER_EVENT_H #define SER_EVENT_H +#include + /* This is used to be able to signal the event loop (or any other select/poll) of events, in a race-free manner. @@ -48,4 +50,8 @@ call is made. */ extern void serial_event_clear (struct serial_event *event); +/* Send a runnable to the main thread. */ + +extern void run_on_main_thread (std::function &&); + #endif diff --git a/gdb/unittests/main-thread-selftests.c b/gdb/unittests/main-thread-selftests.c new file mode 100644 index 0000000..e5bd2d3 --- /dev/null +++ b/gdb/unittests/main-thread-selftests.c @@ -0,0 +1,80 @@ +/* Self tests for run_on_main_thread + + Copyright (C) 2019 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . */ + +#include "defs.h" +#include "gdbsupport/selftest.h" +#include "gdbsupport/block-signals.h" +#include "ser-event.h" +#include "event-loop.h" +#if CXX_STD_THREAD +#include +#endif + +namespace selftests { +namespace main_thread_tests { + +#if CXX_STD_THREAD + +static bool done; + +static void +set_done () +{ + run_on_main_thread ([] () + { + done = true; + }); +} + +static void +run_tests () +{ + std::thread thread; + + done = false; + + { + gdb::block_signals blocker; + + thread = std::thread (set_done); + } + + while (!done && gdb_do_one_event () >= 0) + ; + + /* Actually the test will just hang, but we want to test + something. */ + SELF_CHECK (done); + + thread.join (); +} + +#endif + +} +} + +void +_initialize_main_thread_selftests () +{ +#if CXX_STD_THREAD + selftests::register_test ("main_thread", + selftests::main_thread_tests::run_tests); +#endif +}