From patchwork Wed May 29 21:29:13 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tom Tromey X-Patchwork-Id: 32907 Received: (qmail 63782 invoked by alias); 29 May 2019 21:29:24 -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 63707 invoked by uid 89); 29 May 2019 21:29:24 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-18.5 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, RCVD_IN_DNSWL_NONE, SPF_HELO_PASS autolearn=ham version=3.3.1 spammy=classical X-HELO: gateway22.websitewelcome.com Received: from gateway22.websitewelcome.com (HELO gateway22.websitewelcome.com) (192.185.47.65) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Wed, 29 May 2019 21:29:22 +0000 Received: from cm16.websitewelcome.com (cm16.websitewelcome.com [100.42.49.19]) by gateway22.websitewelcome.com (Postfix) with ESMTP id 83B876F26 for ; Wed, 29 May 2019 16:29:21 -0500 (CDT) Received: from box5379.bluehost.com ([162.241.216.53]) by cmsmtp with SMTP id W68PhwMKS4FKpW68PhHWq4; Wed, 29 May 2019 16:29:21 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=tromey.com; s=default; h=References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Sender:Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=nnMiu54ZW+iG0XA26IJQv0EE/gAv8K27SV9IGOH15PY=; b=cSUzFrOBuO8HZ9N+uYfF+aRenP /lURkzs/WI4pRAzJ5M8bjKAeF8hAkCdg0g5zWhjWtqdfAHFoxeL/WuV+cwAUUhDEmNmijTglLARaS sYD0Omu8FfWhrdZxCkYX4+K05; Received: from 174-29-48-168.hlrn.qwest.net ([174.29.48.168]:41198 helo=bapiya.Home) by box5379.bluehost.com with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.91) (envelope-from ) id 1hW68P-002qwZ-9c; Wed, 29 May 2019 16:29:21 -0500 From: Tom Tromey To: gdb-patches@sourceware.org Cc: Tom Tromey Subject: [PATCH v3 5/8] Introduce run_on_main_thread Date: Wed, 29 May 2019 15:29:13 -0600 Message-Id: <20190529212916.23721-6-tom@tromey.com> In-Reply-To: <20190529212916.23721-1-tom@tromey.com> References: <20190529212916.23721-1-tom@tromey.com> This introduces a way for a callback to be run on the main thread. gdb/ChangeLog 2019-05-29 Tom Tromey * 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. --- gdb/ChangeLog | 8 ++++++ gdb/ser-event.c | 69 +++++++++++++++++++++++++++++++++++++++++++++++++ gdb/ser-event.h | 6 +++++ 3 files changed, 83 insertions(+) diff --git a/gdb/ser-event.c b/gdb/ser-event.c index d3956346246..4870433b287 100644 --- a/gdb/ser-event.c +++ b/gdb/ser-event.c @@ -20,6 +20,10 @@ #include "ser-event.h" #include "serial.h" #include "common/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 +221,68 @@ serial_event_clear (struct serial_event *event) 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. */ + std::swap (local, runnables); + } + + for (auto &item : local) + item (); +} + +/* 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 137348557f9..61a84f9cc79 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 @@ extern void serial_event_set (struct serial_event *event); 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